Problem Formulation for thefluoridealert.org/wp-content/uploads/sf-epa.eco-risk.june_.2009.pdf · ecological risk (US EPA, 1993). In this problem formulation, EFED will present the

Problem Formulation for the

Environmental Fate, Ecological Risk, Endangered Species, and Drinking Water Assessments

in Support of the Registration Review of Sulfuryl Fluoride

Sulfuryl Fluoride (CAS 002699–79-8)

Prepared by: Gabe Rothman, Environmental Scientist Amanda Solliday, Biologist Reviewed by: Mah Shamim, Branch Chief

U. S. Environmental Protection Agency Office of Pesticide Programs Environmental Fate and Effects Division Environmental Risk Branch V 1200 Pennsylvania Ave., NW Mail Code 7507P Washington, DC 20460

June 15, 2009

2 of 50

Table of Contents 1. Purpose........................................................................................................................... 4 2. Problem Formulation ..................................................................................................... 4

2.1. Nature of Regulatory Action.................................................................................... 4 2.2. Regulatory History and Previous Risk Assessments ............................................... 4

3. Stressor Source and Distribution .................................................................................... 6 3.1. Mechanism of Action............................................................................................... 6 3.2. Overview of Pesticide Usage ................................................................................... 6 3.3. Environmental Fate and Transport......................................................................... 10

3.3.1. Degradation..................................................................................................... 11 3.3.2. Transport and Dissipation ............................................................................... 12 3.3.3. Atmospheric Environmental Issues ................................................................ 13 3.3.4. Bioaccumulation ............................................................................................. 16

4. Receptors...................................................................................................................... 16 4.2 Incident Database Review...................................................................................... 18 4.3. Ecosystems Potentially at Risk .............................................................................. 18

5. Assessment Endpoints .................................................................................................. 18 6. Conceptual Model........................................................................................................ 19

6.1. Risk Hypothesis .................................................................................................... 19 6.2. Conceptual Diagram ......................................................................................... 19

7. Analysis Plan ............................................................................................................... 21 7.1. Stressors of Concern ............................................................................................. 22 7.2. Measures of Exposure........................................................................................... 22 7.3. Measures of Effect ................................................................................................ 27 7.4. Integration of Exposure and Effects ...................................................................... 27 7.5. Deterministic and Probabilistic Assessment Methods........................................... 27 7.6. Endangered Species Assessments.......................................................................... 27 7.7. Drinking Water Assessment ................................................................................. 28 7.8. Preliminary Identification of Data Gaps ................................................................ 28

7.8.1. Fate.................................................................................................................. 28 7.8.2. Effects ............................................................................................................. 30

8. References.................................................................................................................... 33 Attachment A.................................................................................................................... 38 Attachment B .................................................................................................................... 41 Attachment C .................................................................................................................... 47

3 of 50

1. Purpose This document functions as a problem formulation characterizing the potential environmental fate and ecological effects of sulfuryl fluoride, a fumigant registered nationally for insect, rodent, and invertebrate pest control on indoor stored food commodities, farm structures, residential structures, road and water transportation vehicles and ships, warehouses, and sheds. There are also special local needs labels for cocoa bean uses in Delaware, New Jersey, Maryland, Virginia, and Pennsylvania and sunflower seed use in California. The problem formulation will provide a framework for analyzing and interpreting data relevant to the environmental fate, ecological risk and endangered species effects of sulfuryl fluoride. Any data gaps or uncertainties will also be discussed and addressed.

2. Problem Formulation

2.1. Nature of Regulatory Action

Under the Federal Insecticide, Fungicide, and Rodenticide Act (FIFRA), all pesticides distributed or sold in the United States generally must be registered by EPA. In determining whether a pesticide can be registered in the U.S., EPA evaluates its safety to non-target species based on a wide range of environmental and health effects studies. In 1996, FIFRA was amended by the Food Quality Protection Act, and EPA was mandated to implement a new program for the periodic review of pesticides, i.e., registration review (http://www.epa.gov/oppsrrd1/registration_review/). The registration review program is intended to ensure that, as the ability to assess risk evolves and as policies and practices change, all registered pesticides continue to meet the statutory standard of no unreasonable adverse effects to human health and the environment. Changes in science, public policy, and pesticide use practices will occur over time. Through the new registration review program, the Agency periodically reevaluates pesticides to make sure that as change occurs, products in the marketplace can be used safely.

As part of the implementation of the new Registration Review program pursuant to Section 3(g) of the Federal Insecticide, Fungicide and Rodenticide Act (FIFRA), the Agency is beginning its evaluation of sulfuryl fluoride to determine whether it continues to meet the FIFRA standard for registration. This problem formulation for the environmental fate, ecological risk, endangered species, and drinking water assessment chapter in support of the registration review will be posted in the initial docket opening the public phase of the review process.

2.2. Regulatory History and Previous Risk Assessments Sulfuryl fluoride was originally registered for use in the United States in 1959. It is currently used in farm structures, residential structures, road and water transportation vehicles and ships, warehouses, and sheds. In 2004, sulfuryl fluoride was registered for food uses including almonds, barley, beech nuts, beef/range/feeder cattle, brazil nuts, butternut, cashews, cheese/cheese byproducts, chestnuts, chinquapins, cocoa, coconuts,

4 of 50

http://www.epa.gov/oppsrrd1/registration_review/

coffee, field corn, pop corn, cottonseed, dates, figs, filberts, dried fruits, ginger, grapes, herbs and spices, hickory nuts, macadamia nuts, meat products, millets, oats, peanuts, pecans, pine nuts, pistachio nuts, prunes, rice, sorghum, sunflowers, triticales, dried vegetables, walnuts, and wheat. There are also seven Special Local Needs Registration Section 24(c) labels. Six Special Local Needs labels increase the maximum allowable dosage of sulfuryl fluoride to 3,750 oz-hour/1K ft3 in the states of Delaware, Maryland, New Jersey, Pennsylvania, and Virginia. One other special local needs label in California is for fumigation on sunflower seeds at a maximum allowable dosage of 1,500 oz-hour/1K ft3 (US EPA, 1993). Sulfuryl fluoride is registered as a restricted use pesticide and thus requires application by or under the direct supervision of certified personnel. Sulfuryl fluoride controls adult insect pests such as termites, powder post beetles, old house borers, bedbugs, carpet beetles, clothes moths and cockroaches, as well as rodent pests such as rats and mice. Sulfuryl fluoride has been deemed as a methyl bromide alternative by the agency. Methyl bromide has been a widely used fumigant for pre-plant soil incorporated and food commodity applications. However, methyl bromide is designated as a Class I Ozone Depleting Substance by the EPA Office of Air, and therefore possesses the largest concern for the destruction of stratospheric ozone. All Class I Ozone Depleting substances are being phased out as per the Montreal Protocol (US EPA, 2009[1]). Sulfuryl fluoride registered uses are similar to some past and current critical exemption uses of methyl bromide. The Agency previously conducted a fate and hazard assessment on sulfuryl fluoride during reregistration. The fate and hazard assessment, completed in June 1985, supported the most recent RED, issued in September 1993. Toxicological information for sulfuryl fluoride was only available for mammals. Despite high toxicity to mammals, none of the Agency’s levels of concern were exceeded due to the indoor use pattern. The 1985 document concluded that sulfuryl fluoride poses no risk to aquatic or terrestrial organisms since it is primarily used indoors. No mitigation strategies were proposed for ecological risk (US EPA, 1993). In this problem formulation, EFED will present the analysis plan for the registration review risk assessment related to the terrestrial organisms including birds, mammals, and terrestrial plants. All labels (Pro Fume®, Master Fume™, Vikane®, and Zythor) require mechanical ventilation and aeration from structures after fumigation when the maximum allowed dosage is achieved. Labels require a minimum of a one-hour period of mechanical ventilation controlling emissions through air ducts at air flow rates of 5,000 cfm. This mechanical ventilation period is followed by an uncontrolled aeration period. Therefore, it is expected that all sulfuryl fluoride residues that exist inside the structure will be displaced to the outdoors resulting in significant ground level inhalation exposure for terrestrial organisms to sulfuryl fluoride as a result of mechanical ventilation and aeration. There can also be a repeat cycle based upon pest pressure and the nature of the structure. Sulfuryl fluoride’s potential for outdoor exposure was discussed in detail by the California Department of Pesticide Regulation (CALDPR) during their Scientific Review Panel (CALDPR, 2006[1]). As a result of the Scientific Review Panel’s findings,

5 of 50

CALDPR continued to recommend requiring buffer zones and entry restrictions for neighbors and bystanders in the vicinity of treated structures and facilities (CALDPR, 2005[1]). CALDPR also designated sulfuryl fluoride as a toxic air pollutant (CALDPR, 2005[2]). 3. Stressor Source and Distribution

3.1. Mechanism of Action

Sulfuryl fluoride is a fumigant and therefore will exist mainly in the gas phase. The fumigant penetrates the exoskeleton or epidermal membrane, for insects and rodents, respectively, and breaks down to the fluoride anion via hydrolysis. Fluoride disrupts glycolysis formation and the fatty acid cycles which result in deficiencies in protein and amino acid production. As a result, insecticidal and rodenticidal mortality is a consequence of the resulting deficiency of cellular energy necessary to maintain vital bodily functions (Dow Agrosciences, 2009).

3.2. Overview of Pesticide Usage There are a number of active Section 3 products containing sulfuryl fluoride, all restricted indoor uses. There are no outdoor pre-plant soil incorporated uses. There are also six special local needs Section 24(c) labels. Table 1 shows the each label, post-harvest commodity and/or structural use, and maximum dosage (concentration multiplied by time) for each use. In all cases, sulfuryl fluoride is contained as a solution in pressurized steel cyclinders (Dow Agrosciences, 2009). Upon release, sulfuryl fluoride immediately volatilizes and diffuses in the indoor environment. In all cases, chloropicrin is added to the product as an odorant warning agent since sulfuryl fluoride is odorless. Table 1. Sulfuryl fluoride end-use labels and application methods.

Label(s) Formulations

Application Method

Maximum Dosage and

Concentration per Treatment

Maximum Number of

Applications per Season

Intervals between

Applications Vikane ® 99.8 %

Sulfuryl Fluoride

• Structural Fumigation:

Non agricultural

buildings, general

residential, ships and boats, wood

protection to buildings, shipping

containers

1,500 oz•hours per 1K cubic foot

128 oz per 1K

cubic foot

NS N/A

6 of 50


Application Method

Maximum Dosage and


Maximum Number of


Intervals between

Applications ProFume ® 99.8 %

Sulfuryl Fluoride


Farm structures,

airtight chambers, road

vehicles, residential,

warehouses, buildings, boats

and ships, restaurants

• Commodity

Fumigation:

Almonds, barley, beechnuts,

beef/range/feeder cattle, brazil

nuts, butternuts, cashews, cheese,

chestnuts, chinquapins, cocoa, coffee, corn (field and

pop), cottonseed, dates, figs,

filberts, dried fruit, ginger,

grapes, herbs and spices, hickory

nuts, macadamia nuts, meat

products, millets, oats, peanuts, pecans, pine

nuts, pistachios, prunes, rice,

triticales, dried vegetables,

walnuts, wheat


128 oz per 1K

cubic foot

NS N/A

7 of 50


Application Method

Maximum Dosage and


Maximum Number of


Intervals between

Applications Master

Fume ™ 99.8% Sulfuryl

Fluoride • Structural

Fumigation:

Road vehicles, residential,

buildings, ships and boats,

building wood protection


128 oz per 1K

cubic foot

NS N/A

Zythor 99.3% Sulfuryl Fluoride


Road vehicles, warehouses, residential,

buildings, ships and boats,

building wood protection, shipping

containers


128 oz per 1K

cubic foot

NS N/A

DE070001 MD070001 NJ070004 PA070005 VA070002

99.8% Sulfuryl Fluoride

• Indoor Food Use:

Cocoa beans


(Single fumigation event)

3,750 oz•hours per

1K cubic foot (Cumulative of

fumigation events)

128 oz per 1K cubic foot

NS N/A

CA070003 99.8% Sulfuryl Fluoride

• Indoor Food Use:

Sunflower seeds


128 oz per 1K

cubic foot

NS N/A

1 N/A means not applicable. 2 NS means not specified. Nationwide use data for sulfuryl fluoride are available from the EPA Office of Prevention, Pesticides, and Substance’s Toxic Release Inventory (http://www.epa.gov/tri/tridata/index.htm). Food processing facilities are classified under the North American Industry Classification System (NAICS) with code 31 – 33. Thus, entities using sulfuryl fluoride for post-harvest commodities are required to report the use

8 of 50

of sulfuryl fluoride as per Section 313 of the Emergency Planning and Community Right to Know Act (EPCRA) (US EPA, 2009[2]). Table 2 shows the annual use from reporting industries of sulfuryl flouride from 1995 through 2006. In addition, CALDPR requires that all uses of sulfuryl fluoride to be reported (CALDPR, 2005[1]). The total usage for post-harvest commodities, structural applications, as well as total applications in California from 1989 to 2007 obtained from the California Pesticide Use Report (CALPUR) database (http://www.cdpr.ca.gov/docs/pur/purmain.htm) is shown in Table 3. Table 2. Sulfuryl fluoride reported use from the Toxic Release Inventory.

Year Sulfuryl Fluoride Use (lbs/year)

Sulfuryl Fluoride Use (tons/yr)

2006 85,571 43 2005 84,086 42 2004 142,720 71 2003 224,258 112 2002 218,500 109 2001 215,000 108 2000 635,000 318 1999 525,000 263 1998 22,000 11 1997 428,000 214 1996 362,000 181 1995 355,007 178

1 Toxic release inventory use reported use only reflects data from industries required to report per Section 313 of EPCRA.

Table 3. Sulfuryl fluoride reported use in California from California Pesticide Use Report database.

Year

Structural Use (lbs./year)

Post-Harvest Commodity

Sulfuryl Fluoride Use

(lbs./year)

Total Pesticide Use

(lbs./year) 2007 2,107,121 24,955 2,151,450 2006 2,838,272 18,641 2,871,378 2005 3,316,779 9,573 3,335,523 2004 3,265,284 NS 3,270,698 2003 3,106,409 2,196 3,112,078 2002 3,044,001 NS 3,045,084 2001 2,581,983 NS 2,585,842 2000 2,406,134 1,446 2,420,299 1999 2,566,708 NS 2,575,057 1998 2,170,746 NS 2,173,388 1997 1,935,677 NS 1,938,694 1996 1,799,946 NS 1,805,401 1995 1,745,546 NS 1,746,321 1994 1,729,811 53 1,734,437 1993 1,496,666 60 1,502,092 1992 1,444,035 628 1,448,693

9 of 50

Year

Structural Use (lbs./year)

Post-Harvest Commodity

Sulfuryl Fluoride Use

(lbs./year)

Total Pesticide Use

(lbs./year) 1991 1,243,809 10 1,244,657 1990 1,131,854 86 1,138,962 1989 961,964 59 976,967

1 All values rounded up to the nearest whole number. 2 NS means not spectified. It is worthy to note that the California total sulfuryl fluoride use is higher than the Toxic Release Inventory reported amounts. Table 3 suggests that the vast majority of sulfuryl fluoride use, at least in California, is associated with structural uses. This discrepancy can be the result of non-industrial structural uses, not identified by Section 313 EPCRA, not being accounted for in the Toxic Release Inventory. Therefore, most of the nationwide uses reported in the Toxic Release Inventory are most likely associated with post-harvest commodities as reporting requirements are applicable to food processing industries. Given that the labels require mechanical venting and aeration of all fumigated structures and large use quantified at least in California, it is highly probable that large quantities of sulfuryl fluoride are released into the atmosphere each year. The nationwide spatial distribution of indoor uses of sulfuryl fluoride or the post-harvest commodities it is used on is not available. However, sulfuryl fluoride use is most likely prevalent in the Mid-Atlantic states based on the numerous special local needs labels and California as indicated by CALPUR.

3.3. Environmental Fate and Transport Sulfuryl fluoride is released for gas fumigation indoors. However, the labels require mechanical ventilation and aeration of all sulfuryl fluoride residues from the building into the atmosphere after achieving the prescribed dosage. Although sulfuryl fluoride is highly volatile, sulfuryl fluoride can be transported to ground-level via dispersion processes. Data defining the physical, chemical, fate and transport characteristics associated with sulfuryl fluoride are summarized in Table 4. The fate and transport of sulfuryl fluoride in the environment is discussed below. Table 4. General chemical and environmental fate properties of sulfuryl fluoride.

Chemical/Fate parameter Value Source (MRID)

Molecular Weight (g/mol) 102.07 Product Chemistry (MRID 46806202)

Vapor Pressure (torr at 20°C) 12,087 Product Chemistry (MRID 46806202)

Boiling Point (°C) -54°C Product Chemistry (MRID 46806202)

Diffusion in Air Coefficient (cm2/day) 1 7,691 Graham’s Law of Effusion

10 of 50

Chemical/Fate parameter Value Source (MRID)

Octanol-water Partition Coefficient (Log KOW) 2.57 Kenaga, 1957

Octanol-air Partition Coefficient (Log KOA) No Data -

Water Solubility (mg/L; at 20°C) 1,040 mg/L Product Chemistry (MRID 46806202)

Henry's Law Constant (atm-m3 mol-1) 1.56 Vapor Pressure ÷ Solubility

Atmospheric half-life and lifetime (years) <4.5 years (Level I fugacity model atmospheric lifetime)

>300 years (half –life due to

hydroxyl radicals)

>107 years (half-life due to chlorine)

>5,000 years (half-life due to

ozone)

25 – 53 years (atmospheric lifetime due to oceanic uptake)

- Swedish Chemicals Inspectorate Report, 2005

- Papadimitriou et al., 2008

- Sulbaek Andersen et al., 2009

- Sulbaek Andersen et al.

2009

- Muhle et al., 2009

Hydrolysis half lives (days) 3.08 days – pH 5.9 0.292 days – pH 7.0 0.007 days – pH 8.3

Cady and Misra, 1974

Aqueous photolysis half-life (days at 20°C) 1 No Data -

Soil Photolysis half-life (days) No Data -

Aerobic Soil Metabolism half-life (days) No Data -

Anaerobic Soil Metabolism half-life (days) 2 No Data -

Aerobic Aquatic Metabolism half-life (days) No Data -

Anaerobic Aquatic Metabolism half-life (days) No Data -

Organic carbon normalized partition coefficients (KOC)

6.1 ml/g Kenaga, 1957

1 Diffusion in air coefficient for sulfuryl fluoride is calculated using Graham’s Law extrapolation and methanol diffusion properties [Sulfuryl fluoride Dair = 0.159 cm2/sec x (32 g/mol ÷ 102.07 g/mol)1/2]. Methanol diffusion in air coefficient of 0.159 cm2/sec retrieved from EPA On-line tools for Site Assessment Calculation (http://www.epa.gov/athens/learn2model/part-two/onsite/estdiffusion.htm).

3.3.1. Degradation

No information is available regarding biodegradation in soil and water. However, there is limited information available regarding abiotic degradation in air and water. There have been no guideline studies submitted to the Agency for hydrolysis, aqueous photolysis, or photodegradation in air. Sulfuryl fluoride rapidly undergoes hydrolysis, especially under alkaline conditions. The hydrolysis half-life of sulfuryl fluoride ranges from 74 hours for acidic environments to

11 of 50

approximately 10 minutes for alkaline conditions (Cady and Misra, 1974). Fluorosulfuric acid (HSO3F) is formed through a nucleophilic reaction and the fluoride anion is displaced. The reaction pathway and net reaction is shown below (CALDPR, 2006[2]).

There have been several attempts to quantify and characterize the photodegradation and reactivity of sulfuryl fluoride in the atmosphere. The sulfuryl fluoride atmospheric lifetime was determined to be 4.5 years through the Level I fugacity model as per the Swedish Chemicals Inspectorate Report, 2005. However, atmospheric half-lives were determined to be even larger in several laboratory studies at between 300 years to effectively stable when irradiated from an artificial source and exposed to ozone, hydroxyl radicals, and chlorine reactive molecules (Papadimitriou et al., 2008 and Sulbaek Andersen et al., 2008). However, recent work by Muhle et al., 2009 demonstrated that oceanic water bodies to be the most important sink of sulfuryl fluoride residues which the authors attribute to hydrolysis. The study authors calculated the atmospheric residence time of sulfuryl fluoride to be 25 and 53 years due primarily through oceanic uptake. In all cases, degradates were not identified.

3.3.2. Transport and Dissipation

According to the directions for use on all labels, all sulfuryl fluoride residues which reach a prescribed level indoors will eventually be emitted into the atmosphere through building leakage during treatment, mechanical venting post-treatment, and uncontrolled aeration (occuring after mechanical venting). Building leakage can often be controlled via use of tarps, which labels recommend but do not require in all cases. Monitoring data from the California Air Resources Board (CARB) consistently show that outdoor ambient air concentrations peak during mechanical ventilation events (CARB, 2005 [1] and CARB, 2005 [2]). Maximum average concentrations of 1,000,000 μg/m3 (24,000 ppbv) and 29,000 μg/m3 (6,900 ppbv) were found after fumigations outside a 81,000 cubic foot house and 45,000 cubic foot houses, respectively, at multiple sites during each mechanical ventilation period (see Attachment A). The maximum short-term potential emission rate for each outdoor release point (e.g. stacks or vents) from a building can be determined by multiplying the inside sulfuryl fluoride concentration just prior to mechanical venting by the flow velocity in the vent. Since the maximum target indoor equilibrium concentrations on all labels are 128 oz/1K ft3, and the specified release point flow velocity is 5,000 cfm, the maximum potential

12 of 50

instantaneous emission rate is 302.4 g/s for each outdoor release point (128 oz/1,000 ft3 × 28.35 g/oz × 5,000 ft3/min × min/60s = 302.4 g/s). However, emission rates will most likely be lower but will vary due to factors such as temperature and wind stress on a building. Once in the atmosphere, sulfuryl fluoride posseses a very large vapor pressure of 12,087 torr suggesting that sulfuryl fluoride will exist mainly as a gas. Considering the large atmospheric half-life of at least 4.5 years, long range transport will likely be a concern. According to the Swedish Chemicals Inspectorate Report, 2005, the Level I fugacity model indicated that sulfuryl fluoride possesses an atmospheric mixing time of 0.5 years. Therefore, the report concluded that sulfuryl fluoride would be equally distributed through the global atmosphere considering the large atmospheric half life in comparison to the mixing time. The Swedish report also described the results of the Level II fugacity model which indicated that based on the current use pattern, almost all of sulfuryl fluoride residues would exist in air at a global background concentration of < 0.5 ppt and that negligible amounts of sulfuryl fluoride would persist on airborne aerosols, sediment, suspended sediment, and the fish compartments (Swedish Chemicals Inspectorate, 2005). Sulfuryl fluoride’s large Henry’s Law Constant of 1.56 supports these findings. Recent work by Muhle et al., 2009 demonstrated that oceans were the dominant sink of sulfuryl fluoride residues in air attributed to hydrolysis processes. The study verified that removal processes via airborne aerosols, terrestrial plants, and fresh water bodies are negligible since these media tend to be acidic in nature as opposed to salt water bodies. The paper also reported that global background concentrations of sufluryl fluoride increased to between 1.35 - 1.55 ppt as of 2007. Based on the above findings, it is likely that sulfuryl fluoride will remain as a gas mainly in the air compartment. Given the indicated long residence time in the atmosphere, long range transport of sulfuryl fluoride is a potential concern. However, given the low affinity for sulfuryl fluoride to partition to aerosols or organic matter for large periods of time, its high vapor pressure, and rapid degradation in water bodies due to hydrolysis, sulfuryl fluoride exposure to aquatic ecosystems via deposition processes is not anticipated to be significant. Sulfuryl fluoride inhalation exposure to terrestrial organisms in the near-field is expected to be the dominant concern. 3.3.3. Atmospheric Environmental Issues

3.3.3.1 Global Warming Potential

Recently, a peer-reviewed journal article from the University of California Irvine presenting research about the quantification of sulfuryl fluoride as a greenhouse gas was published. The efficiency of a gas to absorb outgoing infrared radiation in the atmosphere is directly related to its global warming potential (US EPA, 2002). The paper demonstrated the importance of the atmospheric half-life on the calculation of sulfuryl fluoride’s global warming potential. The paper indicated that for a hypothetical

13 of 50

atmospheric lifetime of 100 years, the global warming potential for sulfuryl fluoride (referring to the cumulative factor by which sulfuryl fluoride is efficient as a greenhouse gas as compared to carbon dioxide over a period of time) is 7,500 over a 20-year period and 3,500 over a 100-year period. The paper also indicated that reactants such as ozone, chlorine, and hydroxyl radicals had a negligible effect on the degradation of sulfuryl fluoride (Sulbaek Andersen et al., 2009). However, Muhle et al., 2009 concluded that ocean water was the dominant sink of sulfuryl fluoride residues in the atmosphere and subsequently calculated the atmospheric residence time of sulfuryl fluoride of between 25 and 53 years. This calculation corresponds to a global warming potential of 7,000 for a 20-year period, 5,000 for a 100-year period, and 1,500 over a 500-year period according to Sulbaek Andersen et al., 2009. In addition, the chemical structure of sulfuryl fluoride is somewhat similar to sulfur hexafluoride (SF6). According to the Intergovernmental Panel on Climate Change (IPCC), sulfur hexafluoride is a potent greenhouse gas. Sulfur hexafluoride possesses an atmospheric lifetime of 3,200 years and a global warming potential of 16,300 for a 20-year window and up to 34,900 for a 500-year window (US EPA, 2002). In addition, the Endangerment and Cause or Contribute Findings for Greenhouse Gases proposed that sulfur hexafluoride as one of six greenhouse gases that, “threatens the public health and welfare of current and future generations”, under section 202(a) of the Clean Air Act (EPA, 2009[3]). Although sulfuryl fluoride is not one of the constituents mentioned in the Endangerment Finding, the chemical’s similar nature to sulfur hexafluoride and recent research suggest that there can be similar ramifications associated with sulfuryl fluoride emissions into the atmosphere. Since climate change is a potential concern for sulfuryl fluoride, both aquatic and terrestrial habitats may be affected. EFED’s risk assessment will consider all present and future chemical-specific studies in conjunction with the evolution of observed and modeled trends concerning potential ecological impacts due to climate change. EFED will also consider the present and expected future trends in sulfuryl fluoride usage to determine the overall impact that sulfuryl fluoride emissions may have on climate change. The Office of Pesticide Programs will also collaborate with various divisions in the EPA Office of Air and Radiation to address climate change in the ecological risk assessment. The Agency has identified the following factors by which climate change may potentially impact aquatic and terrestrial ecosystems (Julius and West, 2008): • Atmospheric Temperature Rise – It is expected that as greenhouse gas

emissions increase, there will be a response in increasing temperatures throughout the troposphere. Therefore, certain processes such as volatilization, flux, and long-range transport of other semi-volatile pesticides and trapped greenhouse gases from natural sources may be accelerated and enhanced (Julius and West, 2008) In addition, higher atmospheric reactivity rates of pesticide VOCs in warmer temperatures may increase levels of tropospheric ozone which can also act as greenhouse gas (US EPA, 2008). These processes can affect both terrestrial

14 of 50

organisms through inhalation uptake and aquatic organisms through deposition of any contaminants.

• Sea Level Rise and Polar Warming – Warming induced by greenhouse gas

emissions will cause seawater to expand due to the fluid’s hypsometric properties. In addition, warming in the arctic can cause sea ice to melt at an accelerated rate. Both of these trends can result in loss of habitat for terrestrial species (Julius and West, 2008)

• Changes in Precipitation and Hydrology – Global warming may result in a

longer season on a planetary scale whereby heavy precipitation events associated with thunderstorms may occur. In addition, additional snow and glacier melt will continue to accelerate exponentially proportional to the rate of global warming. Therefore, increased runoff loaded with other anthropogenic contaminants including pesticides will result which can have increasing adverse effects on aquatic species (Julius and West, 2008).

• Ocean Temperature Rise – Global warming will likely result in a warming of

the oceans. Rise in ocean temperatures have been linked to increased incidents of coral bleaching (Julius and West, 2008).

3.3.3.2 Stratospheric Ozone Depletion Potential

Sulfuryl fluoride is not considered a Level-I or Level-II ozone depleting substance by the EPA Office of Air (US EPA, 2009[1]). In addition, the Sulbaek Andersen et al., 2009 study did not show appreciable degradation of sulfuryl fluoride in an ozone-rich environment, prevalent in the stratosphere, nor did it show any photodissociation in the ultraviolet region of solar radiation (wavelengths between 10 – 400 nm), also present in the stratosphere. Furthermore, Muhle et al., 2009 verified that destruction of sulfuryl fluoride via reation with ozone or photodissociation is marginally important. Since destruction of sulfuryl fluoride is not expected to occur to a large extent in the stratosphere, it is not anticipated that ozone depletion will occur since this process typically occurs through the formation of a stable halogenated radical, which is not expected to form since destruction of sulfuryl fluoride is not expected to occur.

3.3.3.3 Photochemical Ozone Creation Potential Formation of ground-level ozone is not expected to be an issue with sulfuryl fluoride. Sulfuryl fluoride is practically non-reactive in the atmosphere, and the dominant sink of sulfuryl fluoride is through oceanic water bodies. Therefore, it is not anticipated that sulfuryl fluoride will be an ozone precursor since it is not expected to undergo significant chemical transformation in the atmosphere.

15 of 50

3.3.4. Bioaccumulation Bioaccumulation of sulfuryl fluoride residues is not expected to occur significantly in aquatic and terrestrial organisms. First, sulfuryl fluoride is not anticipated to be bioavailable in large quantites considering its trace global background concentration and potential for only acute exposure. Second, the mode of action suggests that sulfuryl fluoride will rapidly breakdown within hydrous tissue. 4. Receptors

4.1. Aquatic and Terrestrial Effects The receptor is the biological entity that is exposed to the stressor (EPA, 1998). Consistent with the process described in the Overview Document (EPA, 2004), this risk assessment uses a surrogate species approach in its evaluation of sulfuryl fluoride. Toxicological data generated from surrogate test species, which are intended to be representative of broad taxonomic groups, are used to extrapolate to potential effects on a variety of species (receptors) included under these taxonomic groupings.

Acute and chronic toxicity data from studies submitted by pesticide registrants along with the available open literature are used to evaluate the potential direct effects of sulfuryl fluoride to the terrestrial receptors identified in this section. This includes toxicity data on the technical grade active ingredient, degradates, and when available, formulated products. The open literature studies are identified through EPA’s ECOTOX database (http://cfpub.epa.gov/ecotox/), which employs a literature search engine for locating chemical toxicity data for aquatic life, terrestrial plants, and wildlife. The evaluation of both sources of data can also provide insight into the direct and indirect effects of sulfuryl fluoride on biotic communities from loss of species that are sensitive to the chemical and from changes in structure and functional characteristics of the affected communities.

Table 5 provides a summary of the taxonomic groups and the surrogate species tested to help understand potential acute ecological effects of pesticides to these non-target taxonomic groups. In addition, the table provides a preliminary overview of the acute toxicity of sulfuryl fluoride based on current data available to the Agency. Table 5. Test Species Evaluated for Assessing Potential Ecological Effects of Sulfuryl Fluoride

Taxonomic Group Example(s) of Surrogate Species Acute Toxicity

Birds1 Mallard (Anas platyrhynchos) Bobwhite (Colinus virginianus) No data

Mammals Laboratory rat (Rattus norvegicus)

Acute Oral LD50 100 mg/kg

Inhalation LC50 642 ppm (females) 660 ppm (males)

Insects Honey bee (Apis mellifera L.) No data

Freshwater fish2 Bluegill sunfish (Lepomis macrochirus) Rainbow trout (Oncorhynchus mykiss) No data

Freshwater invertebrates Water flea (Daphnia magna) No data

16 of 50

http://cfpub.epa.gov/ecotox/

Taxonomic Group Example(s) of Surrogate Species Acute Toxicity

Estuarine/marine fish Sheepshead minnow (Cyprinodon variegatues) No data

Estuarine/marine invertebrates

Mysid shrimp (Americamysis bahia) Eastern oyster (Crassostrea virginica) No data

Terrestrial plants3 Monocots – corn (Zea mays) Dicots – soybean (Glycine max) No data

Aquatic plants and algae Duckweed (Lemna gibba) Green algae (Selenastrum capricornutum)

No data

1 Birds represent surrogates for terrestrial-phase amphibians and reptiles. 2 Freshwater fish are surrogates for aquatic-phase amphibians. 3 Four species of two families of monocots, of which one is corn; six species of at least four dicot families, of which one is soybean. For the purposes of this risk assessment, terrestrial non-target organisms are assumed to occupy areas immediately adjacent to treatment sites. Since sulfuryl fluoride is highly volatile and a gas at room temperature and standard pressure, inhalation of vapor during the aeration phase following fumigation is the major exposure pathway for non-target mammals and birds. Given sulfuryl fluoride’s mode of action, it is unlikely that dermal absorption is a significant pathway for most terrestrial animals, except possibly amphibians. Similarly, sulfuryl fluoride’s high volatility indicated by its high vapor pressure of 12,087 torr (MRID 46806202) and emission of air effluent elements into the outdoor environment from elevated point sources suggest that sulfuryl fluoride contamination of dietary materials for terrestrial wildlife is very unlikely. For these reasons, the hazard assessment will focus on the inhalation pathway for terrestrial animals and contact with terrestrial plants. Given that sulfuryl fluoride is used to control target invertebrates, it is probable that the compound is highly toxic to non-target terrestrial invertebrates. Although studies describing the efficacy of sulfuryl fluoride for the control of target terrestrial invertebrates exist in the open literature (ECOTOX), available data on non-target terrestrial invertebrates do not provide sufficient data to allow for the quantitative assessment of the toxicity of sulfuryl fluoride to non-target terrestrial invertebrates. However, due to the current non-crop use of sulfuryl fluoride, exposure to pollinating insects and other non-target terrestrial invertebrates is expected to be minimal. Therefore, non-target insect studies are not being requested at this time. The present labeled uses of sulfuryl fluoride are not expected to result in adverse impacts to aquatic plant and animal species since deposition of sulfuryl fluoride residues are not expected to occur in the soil (residues available to water bodies via runoff) or water in large quantities for large periods of time. First, due to sulfuryl fluoride’s rapid mixing time of 0.5 years, the present background global concentration is at trace amounts < 1.55 ppt (Swedish Chemicals Inspectorate, 2005). Second, sulfuryl fluoride’s Henry’s Law Constant of 1.56 atm•m3/mol and vapor pressure of 12,087 torr suggests that wet and dry particulate phase deposition processes, respectively should be minimal. In addition, partitioning of sulfuryl fluoride residues from the air to water bodies should be minimal due to the low loading in the global atmosphere and its volatile behavior. The small level

17 of 50

of partitioning of sulfuryl fluoride to ocean water will likely result in further degradation through rapid hydrolysis (Muhle, 2009).

4.2 Incident Database Review No incidents involving wildlife injuries associated with uses of sulfuryl fluoride were documented in the Ecological Incident Information System (EIIS) database, based on a review conducted on February 12, 2009. This database consists of ecological incidents involving pesticides submitted to the EPA from 1994 to present. The number of reports listed in the EIIS database is believed to be only a small fraction of the total incidents involving mortality and other damage to non-target plants and animals from pesticide use. Few resources are allocated to incident reporting. Reporting by states is only voluntary, and individuals discovering incidents may not be informed on the procedure of reporting these occurrences. Additionally, much of the database is generated from registrant-submitted incident reports. Registrants are legally required to provide detailed reports of only “major” ecological incidents involving pesticides, while “minor” incidents are reported aggregately. Because of these organizational difficulties, EIIS is most likely a minimal representation of all pesticide-related ecological incidents. Although there were no reported incidences for this chemical, this does not rule out any existing risks that may potentially impact nontarget organisms.

4.3. Ecosystems Potentially at Risk The ecosystems at risk are often extensive in scope and therefore it may not be possible to identify specific ecosystems during the development of a nation-wide ecological risk assessment. In general, terrestrial ecosystems potentially at risk include the areas adjacent to treated dwellings, non-residential structures, and vehicles including rail cars, automobiles, trucks, buses and surface ships (but not including aircraft). Areas adjacent to the treated structures could include cultivated fields, fencerows and hedgerows, meadows, fallow fields or grasslands, woodlands, riparian habitats and other uncultivated areas.

5. Assessment Endpoints Assessment endpoints represent the actual environmental value that is to be protected, defined by an ecological entity (species, community, or other entity) and its attribute or characteristics (US EPA 2000). For sulfuryl fluoride, the ecological entities may include the following: mammals, birds, terrestrial-phase amphibians, reptiles, and terrestrial plants. The affected attributes for each of these entities may include growth, reproduction, and survival.

18 of 50

6. Conceptual Model For a pesticide to pose an ecological risk, it must reach ecological receptors in biologically significant concentrations. An exposure pathway is the route by which a pesticide moves in the environment from a source to an ecological receptor. For an ecological pathway to be complete, it must have a source, a release mechanism, an environmental transport medium, a point of exposure for ecological receptors, and a feasible route of exposure. The conceptual model for sulfuryl fluoride provides a written description and visual representation of the predicted relationships between sulfuryl fluoride, potential routes of exposure, and the predicted effects for the assessment endpoint. A conceptual model consists of two major components: risk hypothesis and a conceptual diagram (US EPA, 1998).

6.1. Risk Hypothesis A risk hypothesis describes the predicted relationship among the stressor, exposure, and assessment endpoint response along with the rationale for their selection. For sulfuryl fluoride, the following ecological risk hypothesis is being employed for this ecological risk assessment:

Based on the application methods, mode of action, fate and transport, and the sensitivity of non-target terrestrial species, sulfuryl fluoride has the potential to reduce survival, reproduction, and/or growth in non-target mammals, birds, reptiles, terrestrial-phase amphibians and terrestrial plants when used in accordance with the current label. Non-target organisms include federally- listed threatened and endangered species, as well as non-listed species. 6.2. Conceptual Diagram

All labeled uses of sulfuryl fluoride can affect terrestrial organisms outdoors through inhalation after aeration and mechanical ventilation of fumigant residues from treated indoor facilities. Ground-level outdoor monitoring air concentrations in the vicinity of treated structures from the California Air Resources Board, 2004 show that sulfuryl fluoride concentrations can occur at levels of at least 100,000 μg/m3 or 24,000 ppbv (see Attachment 1). In addition, the probability that outdoor air concentrations resulting from sulfuryl fluoride emissions from treated structures exceed the toxicological level of concern is significant for mammals on an acute basis (see Section 7.2, Tables 7 and 8). Figures 1 and 2 are conceptual models showing the potential receptors of concern and the potential attribute changes in the receptors due to exposures of sulfuryl fluoride to terrestrial and aquatic organisms, respectively.

19 of 50

Figure 1. Conceptual model for sulfuryl fluoride effects on terrestrial organisms. Dotted lines indicate exposure pathways that have a low likelihood of contributing to ecological risk.

Stressor

Source/TransportPathways

Receptors

AttributeChange

Sulfuryl Fluoride indoor fumigation application and aeration to the outdoor environment. Controls adult termites, powder post beetles, old house borers, bedbugs, carpet beetles, clothes moths, cockroaches, rats, and mice.

DirectApplication

Spray drift

Food Residues(e.g, treated

seeds, insects)ExposureMedia

Volatilization/Wind

Suspension

Runoff/Erosion

Individual Plants•Seedling emergence

•Vegetative vigor

Individual Animals•Reduced survival•Reduced growth•Reduced reproduction

Habitat Integrity•Reduction in primary productivity•Reduced cover•Community Change

Wet/dry deposition

Food Chain•Reduction in Prey

Birds/ Amphibians/reptiles

/mammals

Birds/Mammals Ingestion

IngestionTerrestrial/riparian plants

Grassess/forbs, fruit, seeds(trees,shrubs)

Soil

Root UptakeMammals

Ingestion

Dermal Uptake/Ingestion

Inhalation

Stressor


Receptors

AttributeChange

Sulfuryl Fluoride indoor fumigation application and aeration to the outdoor environment. Controls adult termites, powder post beetles, old house borers, bedbugs, carpet beetles, clothes moths, cockroaches, rats, and mice.

DirectApplication

Spray drift



Volatilization/Wind

Suspension

Runoff/Erosion

Individual Plants•Seedling emergence

•Vegetative vigor



Wet/dry deposition

Food Chain•Reduction in Prey

Birds/ Amphibians/reptiles

/mammals

Birds/Mammals Ingestion

IngestionTerrestrial/riparian plants

Grassess/forbs, fruit, seeds(trees,shrubs)

Soil

Root UptakeMammals

Ingestion

Dermal Uptake/Ingestion

Inhalation

20 of 50

Figure 2. Conceptual model for sulfuryl fluoride effects on aquatic organisms. Dotted lines indicate exposure pathways that have a low likelihood of contributing to ecological risk.

Stressor


Receptors

AttributeChange

Sulfluryl Fluoride indoor fumigation application and aeration to the outdoor environment. Controls adult termites, powder post beetles, old house borers, bedbugs, carpet beetles, clothes moths, cockroaches, rats, and mice.

DirectApplication

Spray drift



Volatilization/Wind Suspension

Leaching (Infiltration/Percolation)

Water Column/ Sediment

Groundwater

Runoff/Erosion

Uptake/Gills or Integument

Individual Plants•Reduced Survival•Reduced Growth

Aquatic PlantsNon-vascular Vascular



Aquatic AnimalsInvertebrates Only

Food Chain•Reduction in Algae•Reduction in Prey

Fish/aquatic-phase amphibians

•Eggs•Larvae

•Juvenile/Adults

Uptake/cell, roots, leavesIngestionRiparian

PlantTerrestrial exposure pathways see Fig. 3.

Ingestion

Wet/Dry Deposition

7. Analysis Plan In order to address the risk hypothesis, the potential for hazardous effects on the environment is estimated. The use, environmental fate, and ecological effects of sulfuryl fluoride are characterized and integrated to assess the risks. This is accomplished using a risk quotient (ratio of exposure concentration to effects concentration) approach. Although risk is often defined as the likelihood and magnitude of hazardous ecological effects, the risk quotient-based approach does not provide a quantitative estimate of likelihood and/or magnitude of an adverse effect. However, as outlined in the Overview Document (USEPA, 2004), the likelihood of effects to individual organisms from particular uses of sulfuryl fluoride is estimated using the probit dose-response slope and either the level of concern (discussed below) or the actual calculated risk quotient value. This analysis plan will be revisited and may be revised depending upon the data available in the open literature and the information submitted by the public in response to the opening of the Registration Review docket.

21 of 50

7.1. Stressors of Concern Based on available various peer-reviewed journal articles, sulfuryl fluoride is expected to be the dominant stressor present in the environment given various indications of its stability in the atmosphere (Swedish Chemicals Inspectorate Report, 2005; Papadimitriou et al, 2009; Sulbaek Andersen et al., 2009). 7.2. Measures of Exposure Sulfuryl fluoride inhalation exposure in the outdoor terrestrial environment will be assessed relevant to the leakage of sulfuryl fluoride from structures during treatment, and the subsequent release of sulfuryl fluoride residues into the atmosphere during mechanical ventilation and uncontrolled aeration post-treatment. The largest structures that are fumigated will contain the largest mass of sulfuryl fluoride residues and will require the largest time for ventilation and aeration. Therefore, inhalation exposure in the near field will be assessed using fumigations of structures such as food processing plants, warehouses, flour mills, rail cars, and houses. Sulfuryl fluoride emissions from all of the treated structures mentioned above must be quantified in order to determine estimated exposure concentrations (EECs) in the air. The temporal emissions profile from each outdoor release point will be entered into dispersion models to determine acute EECs in the environment. Given the dilution factor from turbulence and downwind transport, it is not anticipated that chronic exposures will be of concern from a single fumigation event. The temporal emissions profile will be developed from indoor monitoring data. The emissions from each building will be calculated based on the loss of sulfuryl fluoride mass over time within the structure. Maximum acute inhalation EECs will be determined in the near field area directly adjacent to treated structures using the PERFUM model. The PERFUM model uses a Gaussian plume approach utilizing straight-line (non-spatially varying) meteorology dictating plume transport and dispersion. To determine acute EECs, the necessary meteorological data and the temporal emissions profile will be used. 5-years of meteorological data will be used consistent with the FIFRA SAP meeting on the PERFUM model on August 24 - 25, 2004. Figure 3 is a schematic of the plume structure and distribution used in PERFUM (Reiss, 2004). Figure 3. Plume structure in PERFUM.

22 of 50

PERFUM uses the identical approach as the Office of Air Quality Planning and Standard’s ISCST3 model to characterize the plume density, shape, and location. Ground-level concenctrations at a specific point are dependent on the wind speed, wind direction as well as atmospheric stability. PERFUM uses an analytical approach to parameterize atmospheric stability and turbulence. Stability classes A, B, and C indicate unstable and turbulent conditions, stability class D indicates neutrally stable conditions, and stability classes E and F indicates stable and stagnate conditions. Wind speed, temperature, and insolation (or cloud cover) is used to ultimately determine the plume width due to turbulence as well as the overall plume rise (EPA, 1995). The plume width and plume rise along the plume centerline along with the emission rate ultimately determines the ground-level concentration. PERFUM contains the added capability of processing predicted exposure concentrations in a probabilistic mode. PERFUM calculates the concentrations in air over a user-specified averaging period at a locus of points focused about rings surrounding a treated area or an emitted point source over a five year period consistent with the meteorological data. PERFUM outputs the concentrations, and the maximum distance to the point where the level of concern is exceeded based on the toxicity endpoint of concern. PERFUM reports estimated concentrations over numerous percentile levels using the whole field distribution, which considers the concentrations at each point over each time step, or a maximum concentration distribution, which considers the singular maximum concentration per time step. Figure 4 shows schematics illustrating the difference in the development of the PERFUM output concentration distribution at one time step for the whole field versus the maximum concentration distributions. The maximum concentration percentile distribution conveys the probability that there will be an exceedance over time only, and the whole field percentile distribution conveys the probability that there will be an exceedance over time and space. Figure 4. PERFUM whole field (left) versus maximum concentration (right) distributions at one time step.

23 of 50

24 of 50

In this problem formulation, PERFUM was used to determine whether present labeled use patterns of sulfuryl fluoride would potentially contribute to ambient air concentrations of concern to mammalian species. Outdoor concentrations were arrived at using the maximum application rate of 8lb. per 1,000 cubic feet (128 oz./1,000 cubic feet) specified on product labels using an exponential decay box model temporal emissions profile which was originally developed for the methyl bromide commodity uses (Dawson, 2008). It is assumed that this approach will be relevant to sulfuryl fluoride since it is expected that both methyl bromide and sulfuryl fluoride will exist as a gas at room temperature. A six hour release was assumed for all scenarios, and the emissions profile was defined based on air exchange rate, building area, building volume, and time after release (see Attachment B, Table B-1). Therefore, the PERFUM modeling accounts for various scenarios of treated buildings such as a range of air exchange rates, building sizes, as well as the consideration of stacks with mechanical ventilation (active aeration), consideration of stack orientation in the horizontal or vertical directions, and the consideration of multiple source contributions for railcar and cargo hold treatment scenarios. All scenarios are assumed to be representative of the sulfuryl fluoride release into the atmosphere after removal of tarps from structures and railcars. The toxicological benchmark (HEC) value of 278,303.6 μg/m3 (64.2 ppm) was selected based on ten percent of the LC50 value of 2,783,036 μg/m3 (642 ppm) (MRID No. 41769101) corresponding to the acute level of concern for endangered species. PERFUM concentration distributions were developed based on a 4-hour averaging period corresponding to the 4 hour exposure period in the acute inhalation mouse study (MRID 41769101). Tables 7 and 8 below shows the percentile concentration and distance from the source to where exceedances occur for the different scenarios modeled for the whole field and maximum concentration distributions, respectively. Both distributions show exceedances at significant levels. For the purposes of the risk assessment, exceedances of less than or equal to the 90th percentile level indicates a significant probability for an exposure of concern. Exceedances occur as low as less than the fifth percentile concentration for the maximum concentration distribution, and the 80th percentile concentration for the whole field concentration distribution. In addition, the 90th percentile concentration for the various scenarios corresponds to a source to point of concern distance as large as 80 meters for the whole field distribution results and exceeding 1,440 meters for the maximum concentration distribution results.

Table 7. PERFUM 4-hour average air maximum concentration distribution minimum percentile of exceedance and maximum distance from building property line to farthest point with level of concern (values in parenthesis) in meters for application rate of 8 lb./1,000 ft.3.

Railcars and Cargo Building Scenarios

Structure Volume

(ft.3)

Exponential Emissions Decay,

Multiple Source, 0.05 AXR,

Passive Aeration, No Stack 1, 2, 3, 4, 5, 6

Exponential Emissions

Decay, Single Source, 0.1

AXR, Passive Aeration, No Stack 1, 2, 3, 6, 7

Exponential Emissions Decay, Single Source,

1.0 AXR, Passive Aeration, No Stack 1, 2,

3, 6, 8


1.0 AXR, Active Aeration, 5 ft. Portable Vertical Stack 1, 2, 3, 7, 8

Exponential Emissions Decay, Single Source ,

1.0 AXR, Active Aeration, 3 ft.

Horizontal Portable Stack 1, 2, 3, 6, 7, 8

1,000 N/A NE NE >90 (NE) NE 2,000 N/A NE NE >90 (NE) >90 (NE) 5,000 NE NE NE >90 (NE) >90 (NE)

10,000 NE NE NE >90 (NE) >90 (NE) 25,000 N/A NE NE 80 (15) 85 (10) 50,000 N/A NE NE 40 (35) 45 (35)

100,000 N/A NE NE 10 (55) 15 (55) 250,000 N/A NE NE <5 (15) <5 (95) 500,000 N/A NE NE <5 (140) <5 (145) 750,000 N/A NE NE <5 (175) <5 (185)

1,000,000 N/A NE NE 10 (45) <5 (215) 2,500,000 N/A NE 90 (220) <5 (385) 10 (65) 5,000,000 N/A NE 60 (360) 15 (495) 15 (550) 7,500,000 N/A NE 35 (1,265) 15 (590) 15 (700)

10,000,000 N/A >90 (NE) 25 (>1,440) 15 (745) 15 (825) 1 PERFUM2 output processing at target concentration of 278,303.6 μg/m3 based on the level of concern for acute endangered species from the most sensitive rat inhalation LC50

value(0.1 x 2,793,036 μg/m3 or 642 ppm) per MRID No. 41769101. 2 PERFUM2 input based on Methyl Bromide indoor fumigation modeling following exponential decay box model emissions profile at an application rate of 8 lb./1000 ft.3, and

specified air exchange rate (AXR) of treated buildings using Bradenton, FL meteorological data per Dawson, 2008. 3 PERFUM2 input release parameters (e.g., stack diameters and flow velocities) consistent with Dawson, 2008 for each scenario. 4 Modeling at 5,000 ft.3 and 10,000 ft.3 representative of railcar and cargo hold structure sizes of 5,238 ft.3 – 6646 ft.3 per CSX website

(http://www.csx.com/?fuseaction=customers.ag_cars-detail&i=1759). Multiple sources accounted for per Dawson, 2008. 5 N/A means not applicable. 6 NE indicates scenarios where no quantifiable adverse effects are predicted by PERFUM. 7 >90 (NE) indicates scenarios where the concentration percentile of exceedance occurs at a level greater than the 90th percentile concentration level. Therefore, adverse effects

for these scenarios are not expected to be significant. 8 All distances from property line to farthest point with level of concern based on 90th percentile exceedance level.

25 of 50

26 of 50

Table 8. PERFUM 4-hour average whole field air concentration distribution minimum percentile of exceedance and maximum distance from building property line to farthest point with level of concern (values in parenthesis) in meters for application rate of 8 lb./1,000 ft.3.


Structure Volume

(ft.3)

Exponential Emissions Decay,

Multiple Source, 0.05 AXR,

Passive Aeration, No Stack 1, 2, 3, 4, 5, 6

Exponential Emissions

Decay, Single Source, 0.1

AXR, Passive Aeration, No Stack 1, 2, 3, 6, 7


1.0 AXR, Passive Aeration, No Stack 1, 2,

3, 6, 8


1.0 AXR, Active Aeration, 5 ft. Portable Vertical Stack 1, 2, 3, 7, 8

Exponential Emissions Decay, Single Source ,

1.0 AXR, Active Aeration, 3 ft.

Horizontal Portable Stack 1, 2, 3, 6, 7, 8

1,000 N/A NE NE NE NE 2,000 N/A NE NE NE >90 (NE) 5,000 NE NE NE >90 (NE) >90 (NE)

10,000 NE NE NE >90 (NE) >90 (NE) 25,000 N/A NE NE >90 (NE) >90 (NE) 50,000 N/A NE NE >90 (NE) >90 (NE)

100,000 N/A NE NE >90 (NE) >90 (NE) 250,000 N/A NE NE 85 (10) 90 (10) 500,000 N/A NE NE 90 (10) 80 (10) 750,000 N/A NE NE 85 (25) 85 (25)

1,000,000 N/A NE NE >90 (NE) 30 (85) 2,500,000 N/A NE >90 (NE) 80 (55) 50 (85) 5,000,000 N/A NE >90 (NE) 90 (45) 70 (70) 7,500,000 N/A NE >90 (NE) >90 (NE) 70 (90)

10,000,000 N/A NE >90 (NE) 90 (60) 95 (80) 1 PERFUM2 output processing at target concentration of 278,303.6 μg/m3 based on the level of concern for acute endangered species from the most sensitive rat inhalation LC50

value(0.1 x 2,793,036 μg/m3 or 642 ppm) per MRID No. 41769101. 2 PERFUM2 input based on Methyl Bromide indoor fumigation modeling following exponential decay box model emissions profile at an application rate of 8 lb./1000 ft.3, and

specified air exchange rate (AXR) of treated buildings using Bradenton, FL meteorological data per Dawson, 2008. 3 PERFUM2 input release parameters (e.g., stack diameters and flow velocities) consistent with Dawson, 2008 for each scenario. 4 Modeling at 5,000 ft.3 and 10,000 ft.3 representative of railcar and cargo hold structure sizes of 5,238 ft.3 – 6646 ft.3 per CSX website

(http://www.csx.com/?fuseaction=customers.ag_cars-detail&i=1759). Multiple sources accounted for per Dawson, 2008. 5 N/A means not applicable. 6 NE indicates scenarios where no quantifiable adverse effects are predicted by PERFUM. 7 >90 (NE) indicates scenarios where the concentration percentile of exceedance occurs at a level greater than the 90th percentile concentration level. Therefore, adverse effects

for these scenarios are not expected to be significant. 8 All distances from property line to farthest point with level of concern based on 90th percentile concentration exceedance level.

7.3. Measures of Effect Ecological effects data are used as measures of direct and indirect impacts to biological receptors. Data are obtained from registrant-submitted studies or from literature studies identified by the ECOTOX database (US EPA, 2007). The acute measures of effect used for animals in this assessment are the LD50, LC50 and EC50. LD stands for "Lethal Dose", and LD50 is the amount of a material (given at one time) that is estimated to cause death in 50% of the test organisms. LC stands for “Lethal Concentration” and LC50 is the concentration of a chemical that is estimated to kill 50% of the test organisms. EC stands for “Effective Concentration” and the EC50 is the concentration of a chemical that is estimated to produce a specific effect in 50% of the test organisms. Endpoints for chronic measures of exposure for listed and non-listed animals are the NOAEL or NOAEC. NOAEL stands for No Observed Adverse Effect Level and refers to the highest tested dose of a substance that shows no harmful effects on test organisms. The NOAEC, or No Observed Adverse Effect Concentration, is the highest test concentration at which none of the observed effects were statistically different from the control. For non-listed plants, only acute exposures are assessed (i.e., EC25 for terrestrial plants and EC50 for aquatic plants), and for listed plants either the NOAEC or EC05 is used. 7.4. Integration of Exposure and Effects Risk characterization is the integration of exposure and ecological effects characterization to determine the potential ecological risk from the uses of sulfuryl fluoride and the likelihood of direct and indirect effects to non-target organisms in terrestrial habitats. The exposure and toxicity effects data are integrated in order to evaluate the risks of adverse ecological effects on non-target species. For the assessment of sulfuryl fluoride risks, the risk quotient (RQ) method is used to compare exposure and measured toxicity values. EECs are divided by acute and chronic toxicity values. The resulting RQs are then compared to the Agency’s Levels of Concern (LOCs) (USEPA 2004). These criteria are used to indicate when the use of sulfuryl fluoride, as directed on the label, has the potential to cause adverse direct or indirect effects to non-target organisms. 7.5. Deterministic and Probabilistic Assessment Methods The quantitative assessment of risk will primarily depend on the deterministic point-estimate based approach described in the risk assessment. An effort will be made to further qualitatively describe risk using probabilistic tools that the Agency has developed. These tools have been reviewed by FIFRA Scientific Advisory Panels (http://www.epa.gov/scipoly/sap/index.htm) and have been deemed as appropriate means of refining assessments where deterministic approaches have identified risks. 7.6. Endangered Species Assessments Consistent with the Agency’s responsibility under the Endangered Species Act (ESA), the Agency will evaluate risks to federally-listed threatened and/or endangered species from registered uses of sulfuryl fluoride. This assessment will be conducted in

27 of 50

http://www.epa.gov/scipoly/sap/index.htm

accordance with the Overview Document (US EPA, 2004), provisions of the ESA, and the US Fish & Wildlife Services’ Endangered Species Consultation Handbook (US FWS/NMFS, 1998). The assessment of effects associated with the registration of sulfuryl fluoride is based on an action area. The action area is considered to be the area directly or indirectly affected by the federal action, as indicated by the exceedance of Agency Levels of Concern (LOC). The Agency’s approach to defining the action area under the provisions of the Overview Document (US EPA, 2004) considers the results of the risk assessment process to establish boundaries for that action area with the understanding that exposures below the Agency’s defined LOCs constitute a no-effect threshold. For the purposes of this assessment, attention will be focused on the footprint of the action (i.e. the area where sulfuryl fluoride application occurs), and all areas where offsite transport (e.g. advection and dispersion) may result in potential exposure that exceeds the Agency’s LOCs. Specific measures of ecological effects that define the action area for listed species include any direct and indirect effects and/or potential modification of its critical habitat, including reduction in survival, growth, and reproduction, as well as any other sublethal effects. Therefore, the action area extends to the point where environmental exposures are below any measured lethal or sublethal effect threshold for any biological entity at the whole organism, organ, tissue, and cellular level of organization. In situations where it is not possible to determine the threshold for an observed effect, the action area is not spatially limited and is assumed to be the entire United States.

7.7. Drinking Water Assessment A drinking water assessment will not be conducted for sulfuryl fluoride. The present indoor gas releases of sulfuryl fluoride and subsequent releases in the atmosphere is not anticipated to result in surface and groundwater contamination which impact drinking water sources.

7.8. Preliminary Identification of Data Gaps

7.8.1. Fate At this time, the following studies and data are being requested regarding the fate of sulfuryl fluoride: • Measurement of Henry’s Law Constant (No guideline number) The data gaps are discussed below and in Table 8.

28 of 50

Table 8. Available environmental fate data for sulfuryl fluoride and remaining data gaps.

Guideline Description MRID Classification Data Gap?

835.2120 Hydrolysis Cady and Misra, 1974

In Review No

835.2240 Photodegradation in water N/A N/A No

835.2410 Photodegradation in soil N/A N/A No

835.4100 Aerobic soil metabolism N/A N/A No

835.4200 Anaerobic soil metabolism N/A N/A No

835.4300 Aerobic Aquatic Metabolism

N/A N/A No

835.4400 Anaerobic Aquatic Metabolism

N/A N/A No

835.1230 835.1240

Leaching and adsorption/ desorption

N/A N/A No

835.8100 Field Volatility N/A N/A No

835.6100 Terrestrial Field Dissipation N/A N/A No

850.1710 850.1730 850.1850

Aquatic organisms –bioavailability,

biomagnification, toxicity

N/A N/A No

No Number

Photodegradation in Air Papadimitriou et al., 2008

Sulbaek

Andersen et al., 2009

Muhle et al.,

2009

In Review No

No Number

Indoor and Outdoor Air Monitoring

46278003 46278004 46278005 46278006 46278007 46278008 46278010 46307901 47164501

In Review

No

No Number

Measurement of Henry’s Law Constant

None Data Requested Yes

*Note –The present labeled uses of sulfuryl fluoride are not expected to result in adverse impacts to aquatic plant and animal species since deposition of sulfuryl fluoride residues are not expected to occur in the soil (residues available to water bodies via runoff) or water in large quantities for large periods of time. Henry’s Law Constant The measured Henry’s Law Constant is being requested at this time to confirm the deposition resistance properties of airborne sulfuryl fluoride residues to the terrestrial and aquatic environments.

29 of 50

7.8.2. Effects Although the Part 158 data requirements for ecological toxicity studies have been fulfilled based on sulfuryl fluoride’s current designation as an indoor use, exposure to non-target organisms may result from aeration following application. Chronic effects are not a concern, as the compound is highly volatile and will not remain at ground level for extended periods of time. Data gaps include avian inhalation and terrestrial plant studies. The data gaps are discussed below (Tables 9 – 11).

Table 9. Available ecological effects data for terrestrial animals exposed to sulfuryl fluoride.

Guideline Description MRID/

Accession Classification Data Gap?

850.2100 Avian oral toxicity None Not applicable No

850.2200 Avian dietary toxicity None Not applicable No

850.2300 Avian reproduction None Not applicable No

870.1100 Mammalian oral toxicity 00043314 Acceptable No

870.1300 Mammalian inhalation 41769101 Acceptable No

Non-guideline

Avian inhalation None Not applicable Yes1

850.3020 Honeybee acute contact toxicity

None Not applicable No2

1Data are required for either bobwhite quail or mallard and a passerine species. Please consult with Agency regarding protocol. 2 Because sulfuryl fluoride is highly toxic to terrestrial invertebrate species (target organism), toxicity to non-target terrestrial invertebrates is assumed. However, sulfuryl fluoride has a non-crop use pattern, and exposure to pollinating insects and other non-target terrestrial invertebrates is expected to be minimal, Therefore, data for terrestrial invertebrates are not requested at this time.

30 of 50

Table 10. Available ecological effects data for aquatic animals exposed to sulfuryl fluoride.

Guideline Description MRID/ Accession

Classification Data Gap?

850.1075 Freshwater fish – Acute toxicity

None Not applicable No

850.1075 Saltwater fish – Acute toxicity


850.1400 Freshwater fish – early life stage test


850.1400 Saltwater fish – early life stage test


850.1500 Fish – life cycle test


850.1010 Freshwater invertebrates – Acute toxicity


850.1025 850.1035 850.1045 850.1055

Saltwater invertebrates – Acute toxicity


850.1300 Freshwater invertebrate – life cycle test


850.1350 Saltwater invertebrates – life cycle test


*Note – Toxicity data for aquatic organisms are not being requested at this time because the present labeled uses of sulfuryl fluoride are not expected to result in adverse impacts to aquatic plant and animal species. The deposition of sulfuryl fluoride residues are not expected to occur in the soil (residues available to water bodies via runoff) or water in large quantities for large periods of time.

31 of 50

Table 11. Available ecological effects data for plants exposed to sulfuryl fluoride.

Guideline Description MRID Classification Data Gap?

850.4100 Terrestrial Plant toxicity: Tier I seedling emergence


850.4225 Terrestrial Plant toxicity: Tier 2 seedling emergence


850.4150 Terrestrial Plant toxicity: Tier I vegetative vigor


850.4150 Terrestrial Plant toxicity: Tier 2 vegetative vigor


Non-guideline

Terrestrial Plant special study None Not applicable Yes1

850.5400 Aquatic Plant Growth: algae None Not applicable No

850.4400 Aquatic Plant Growth: vascular plants


1No data are available to the Agency regarding the toxicity of sulfuryl fluoride to terrestrial plants. For the Terrestrial Plant special study, a short-term enclosure to mimic the passage of vapor through the plants’ surrounding atmosphere is needed. Please consult Agency regarding protocol.

*Note – Toxicity data for aquatic organisms are not being requested at this time because the present labeled uses of sulfuryl fluoride are not expected to result in adverse impacts to aquatic plant and animal species. The deposition of sulfuryl fluoride residues are not expected to occur in the soil (residues available to water bodies via runoff) or water in large quantities for large periods of time. Data Gaps Avian Inhalation Because sulfuryl fluoride is highly volatile and gaseous at room temperature and standard pressure, inhalation of vapor following structural fumigation is the major potential exposure pathway for non-target mammals and birds. Current data suggest that during sulfuryl fluoride fumigation of structures (including homes, non-residental structures such as warehouses, mills and barns, construction materials and vehicles including automobiles, rail cars and ships), the gas is released to the outdoor atmosphere during the aeration phase. Sulfuryl fluoride is toxic to mammals on an acute inhalation basis (LC50 = 642 ppm, MRID 41769101), and preliminary calculations predict that exposure concentrations are high enough to create a potential risk to non-target mammalian species (Section 7.2.1). Both maximum concentration and whole field distributions show exceedance at significant levels based on the toxicological benchmark (HEC) value of 64.2 ppm (278,303.6 μg/m3) (Table 7 and 8). This value was selected based on 10 percent of the LC50 value of 642 ppm (2,783,036 μg/m3) (MRID No. 41769101), corresponding to the acute level of concern for endangered species. Additionally, the area of potential exposure to non-target organisms exceeds 1,440 meters for the maximum concentration distribution and 80 meters for the whole field distribution, based on the 90th percentile concentration for the various scenarios. These preliminary estimates of risk are based on mammalian inhalation data, and no data is available to the Agency regarding sulfuryl fluoride toxicity to avian species via

32 of 50

inhalation. In the absence of such data, insufficient information exists to preclude concerns for direct toxic effects to non-target birds. Terrestrial Plant special study No quantitative data is available to the Agency regarding sulfuryl fluoride toxicity to plants. Exposure potential exists during the aeration phase following structural fumigation. Sulfuryl fluoride has a general mechanism of action that indicates the chemical may have toxicity to plant species, and label language also suggests this compound is high toxic to plants (ex. “Remove all desirable growing plants from the space to be fumigated.” Zythor, 7/16/07). No data are available to assess the toxicity of sulfuryl fluoride to vegetation near release points. In the absence of such data, insufficient information exists to preclude concerns for direct toxic effects to non-target plant species. 8. References Anderson, B. 2008. Performance Evaluation Metrics for Long Range Transport Models. Presented at The

9th Modeling Conference, Research Triangle Park, NC. October 9, 2008. http://www.epa.gov/ scram001/9thmodconf/9thmod_lrtperfevalmeth.pdf. Accessed February 2009.

Armitage, J.M. and F.A.P.C. Gobas. 2007. A Terrestrial Food-Chain Bioaccumulation Model for POPs.

Environ. Sci. Technol., 41(11):4019 -4025. Cady, G. H.; Misra, S. 1974. Hydrolysis of sulfuryl fluoride. Inorg. Chem. 13: 837–841. California Air Resources Board 2005 [1]. Report for the Air Monitoring Around a Structural Application

of Sulfuryl Fluoride in Grass Valley, CA - Summer 2004. Sacramento, CA. http://www.cdpr.ca.gov/docs/emon/pubs/tac/studies/sulfuryl_fl.htm. Acessed February 2009.

California Air Resources Board 2005 [2]. Report for the Air Monitoring Around a Structural Application

of Sulfuryl Fluoride in Loomis, CA - Summer 2004. Sacramento, CA. http://www.cdpr.ca.gov/docs/emon/pubs/tac/studies/sulfuryl_fl.htm. Acessed February 2009.

California Department of Pesticide Regulation 2005 [1]. Recommended Permit Conditions for Sulfuryl

Fluoride (Profume) for Nonresidential Facilities. Letter from Mary-Ann Warmerdam to County Agricultural Commissioners. May 18, 2005

California Department of Pesticide Regulation 2005 [2]. Findings on the Health Effects of the Active

Ingredient: Sulfuryl Fluoride. Sacramento, CA. http://www.cdpr.ca.gov/docs/emon/pubs/tac/ tacpdfs/sulfluor/srp_findings.pdf. Accessed February 2009.

California Department of Pesticide Regulation 2006 [1]. Findings of the Scientific Review Panel on the

Proposed Identification of Sulfuryl Fluoride as a Toxic Air Contaminant as adopted at the Panel’s June 26, 2006 Meeting. Sacramento, CA. http://www.cdpr.ca.gov/docs/emon/pubs/tac/tacpdfs/ sulfluor/srp_findings.pdf. Accessed February 2009.

California Department of Pesticide Regulation 2006 [2]. Sulfuryl Fluoride (Vikane®) Risk Characterization Document. Volume III - Environmental Fate. Sacramento, CA. http://www.cdpr.ca.gov/docs/emon/pubs/tac/finaleval/sulf_fluor.htm. Accessed February 2009.

California Department of Pesticide Regulation 2009. Pesticide Use Report. Sacramento, CA. http://www.cdpr.ca.gov/docs/pur/purmain.htm. Accessed February 2009.

33 of 50

http://www.epa.gov/

http://www.cdpr.ca.gov/docs/emon/pubs/tac/studies/sulfuryl_fl.htm

http://www.cdpr.ca.gov/docs/emon/pubs/tac/studies/sulfuryl_fl.htm

http://www.cdpr.ca.gov/docs/emon/pubs/tac/finaleval/sulf_fluor.htm

CFR 40. 2007. Code of Federal Regulations 40 Parts 150 to 189. Protection of the Environment. U.S.

Government Printing Office. Czub, G. and M.S. McLachlan. 2004. Bioaccumulation Potential of Persistent Organic Chemicals in

Humans. Environ. Sci. Technol. 38:2406-2412. Dawson, J. 2008. Second Addenda to the 2006 (DP Barcode 304623) Phase 5 Human Health Risk

Assessment for Commodity Uses. Office of Pesticide Programs. Washington, DC. (November 26, 2008) (EPA DP Barcode 304612).

Dillon, T. J.; Horowitz, A.; Crowley, J. N. The atmospheric chemistry of sulphuryl fluoride,SO2F2. Atmos.

Chem. Phys. 2008, 8, 1547–1557. Dow Agrosciences 2009. Sulfuryl Fluoride Gas Fumigant. Brochure. http://www.dowagro.com/

PublishedLiterature/dh_0061/0901b803800618fb.pdf?filepath=/uk/pdfs/noreg/011-01270.pdf&fromPage=GetDoc

Julius, S.H. and West, J.M. 2008. Preliminary Review of Adaptation Options for Climate-Sensitive

Ecosystems and Resources. Environmental Protection Agency. Washington, D.C. June 2008. http://www.epa.gov/ord/npd/globalresearch-intro.htm. Accessed June 2009.

Kelly, B.C. and F.A.P.C. Gobas. 2003. An Arctic Terrestrial Food-Chain Bioaccumulation Model for

Persistent Organic Pollutants. Environ. Sci. Technol. 37:2966-2974. Kelly, B.C., Ikonomou, M.G., Blair, J.D., Morin, A.E., and F.A.P.C. Gobas. 2007. Food Web-Specific

Biomagnification of Persistent Organic Pollutants. Science. 317:236-239. Kenaga, E. 1957. Some biological, chemical and physical properties of sulfuryl fluoride as an insecticidal

fumigant. Journal of Economic Entomology 50(1):1-6. McLachlan, M.S. 1996. Bioaccumulation of Hydrophobic Chemicals in Agricultural Food Chains. Environ.

Sci. Technol. 30:252-259. Mühle, J., .Huang, J., Weiss, R.F., Prinn, R.G., Miller, B.R., Salameh, P.K., Harth, C.M., Fraser, P.J.,

Porter, L.W., Greally, B.R., O’Doherty, S.O., and Simmonds, P.G. 2009. Sulfuryl fluoride in the global atmosphere, J. Geophys. Res., 114, D05306, doi:10.1029/2008JD011162.

Papadimitriou, V. C.; Portmann, R. W.; Fahey, D. W.; Muhle, J.;Weiss, R. F.; Burkholder, J. B. 2008.

Experimental and theoretical studyof the atmospheric chemistry and global warming potential of SO2F2. J. Phys. Chem., 112, 12657-12666.

Reiss, R. and Giffin J., 2004. A Probablistic Exposure and Risk Model for Fumigant Bystander Exposures

using Iodomethane as a Case Study”. Report prepared for the FIFRA Science Advisory Panel and sponsored by Arvesta Corporation.

Sharpe, S. and D. Mackay. 2000. A Framework for Evaluating Bioaccumulation in Food Webs. Environ.

Sci. Technol. 34:2373-2379. Sulbaeck Andersen, M.P., Blake, D.R., Rowland, F.S., Hurley, M.D., and Wallington, T.J. 2009.

Atmopsheric chemistry of sulfuryl fluoride: Reaction with OH Radicals, Cl atoms, and O3, Atmospheric Lifetime, IR Spectrum, and Global Warming Potential. Env. Sci Tech.. 43(4): 1067-1070.

Swedish Chemical Inspectorate 2005. Sulfuryl Fluoride/Vikane (PT8), Document III-B7, Ecotoxicological

Data for the Biocidal Product. Swedish Chemicals Inspectorate. Sweden.

34 of 50

U.S. Environmental Protection Agency (US EPA) 1995. Screen3 Model User’s Guide, Washington, D.C.

EPA/630/R-95/002F. September 1995. http://www.epa.gov/scram001/userg/screen/screen3d.pdf. Accessed March 2009.

U.S. Environmental Protection Agency (US EPA) 1998. Guidelines for Ecological Risk Assessment. Risk

Assessment Forum, Office of Research and Development, Washington, D.C. EPA/630/R-95/002F. April 1998. http://cfpub.epa.gov/ncea/cfm/recordisplay.cfm?deid=30759. Accessed January 2009.

US EPA 2002. Greenhouse Gases and Global Warming Potential Values – Excerpt from the Inventory of

U.S. Greenhouse Emissions and Sinks: 1990 – 2000. Office of Atmospheric Programs, Washington DC. http://yosemite.epa.gov/oar/GlobalWarming.nsf/UniqueKeyLookup/ SHSU5BUM9T/$File/ghg_gwp.pdf. Accessed February 2009.

US EPA 2004. Overview of the Ecological Risk Assessment Process in the Office of Pesticide Programs.

U.S. Environmental Protection Agency, Office of Prevention, Pesticides and Toxic Substances, Office of Pesticide Programs, Washington DC. January 23, 2004.

US EPA 2006. Reregistration Eligibility Decision: Sulfuryl Fluoride. U.S. Environmental Protection

Agency, Office of Pesticide Programs, Washington, DC. September, 1993. US EPA 2007a. Ecological Incident Information System. http://www.epa.gov/espp/consultation/ecorisk-

overview.pdf. Accessed January 2009. US EPA 2007b. 40 CFR Part 158. Pesticides; Data Requirements for Conventional Chemicals: Final Rule.

72 FR 60934. October 26, 2007. US EPA 2007c. ECOTOXicology Database. Office of Research and Development National Health and

Environmental Effects Research Laboratory’s (NHEERL’s) Mid-Continent Ecology Division (MED). http://cfpub.epa.gov/ecotox/. Accessed January 2009.

US EPA 2008. Assessment of the Impacts of Global Change on Regional U.S. Air Quality: A Synthesis of

Climate Change Impacts on Ground-Level Ozone. Office of Research and Development. Washington, D.C. EPA/600/R-07/094F. April 2009. http://cfpub.epa.gov/ncea/cfm/ recordisplay.cfm?deid=203459. Accessed June 2009.

US EPA 2009 [1]. Ozone Layer Depletion. Office of Atmopsheric Programs. Washington, D.C.

http://www.epa.gov/ozone/strathome.html. Accessed February 2009. US EPA 2009 [2]. Toxic Release Inventory Program. Office of Pollution, Pesticides, and Toxic

Substances. Washington, D.C. http://www.epa.gov/tri/. Accessed Feburary 2009. US EPA 2009 [3]. “Adoption Proposed Endangerment and Cause or Contribute Findings for Greenhouse

Gases Under Section 202(a) of the Clean Air Act”, in Federal Register, Vol. 74, No. 78, 2009, pp. 18886 - 18910. US EPA, Office of Air and Radiation. Washington, DC.

U.S. Fish and Wildlife Service (USFWS) and National Marine Fisheries Service (NMFS) 1998.

Endangered Species Consultation Handbook: Procedures for Conducting Consultation and Conference Activities Under Section 7 of the Endangered Species Act. Final Draft. March 1998.

35 of 50

http://cfpub.epa.gov/ncea/cfm/recordisplay.cfm?deid=30759

http://yosemite.epa.gov/oar/GlobalWarming.nsf/UniqueKeyLookup/

http://www.epa.gov/espp/consultation/ecorisk-overview.pdf

http://www.epa.gov/espp/consultation/ecorisk-overview.pdf

http://cfpub.epa.gov/ecotox/

http://cfpub.epa.gov/ncea/cfm/

SUBMITTED FATE STUDIES: MRID 46278003 Barnekow, D.; Byrne, S.; Foster, D. (2002) Determination of Atmospheric

Concentrations of Sulfuryl Fluoride Following Fumigation of Mills Using ProFume - North America 2000. Project Number: 000329, F45323. Unpublished study prepared by Paragon Research Services, Minnesota Valley Testing Labs. and Dow AgroSciences LLC. 209 p.

46278004 Barnekow, D.; Byrne, S.; Foster, D.; et. al. (2001) Determination of Atmospheric of

Sulfuryl Fluoride Following Fumigation of Mills Using ProFume - North America 2001. Project Number: 010039, F45323, 26367019/5021/2. Unpublished study prepared by Paragon Research Services, Minnesota Valley Testing Labs and Dow Agrosciences LLC. 246 p.

46278005 Barnekow, D.; Byrne, S.; Foster, D. (2002) Determination of Exposure Potential to

Workers and Atmospheric Concentrations of Sulfuryl Fluoride During and Following Fumigation of Mills Using ProFume - North America 2002. Project Number: 020039, F45323. Unpublished study prepared by Paragon Research Services, Minnesota Valley Testing Labs and Dow Agrosciences LLC. 150 p.

46278006 Barnekow, D. (2004) Summary Report - Determination of Atmospheric Concentrations

of Sulfuryl Flouride Following Fumigation of a Mill Using ProFume - Germany 2000. Project Number: GH/C/5731, GHE/P/8682, 000303. Unpublished study prepared by Dow Agrosciences LLC. 143 p.


of Sulfuryl Fluoride and Occupational Exposure of Fumigators During the Structural Fumigation of a Mill Using ProFume: Germany 2002. Project Number: GH/C/5735, GHE/P/9910, DOS/299/023404. Unpublished study prepared by Dow Agrosciences LLC and Huntingdon Life Sciences, Ltd. 166 p.


of Sulfuryl Flouride Following Fumigation of a Mill Using Profume - Italy 2001. Project Number: GH/C/5734, GHE/P/9902, 010073. Unpublished study prepared by Dow Agrosciences LLC and Minnesota Valley Testing Labs. 154 p.


of Sulfuryl Fluoride Following Fumigation of a Mill Using ProFume - UK 2002. Project Number: GH/C/5733, 26367019/19, AF/6268/DE. Unpublished study prepared by Dow Agrosciences LLC, Agrisearch UK, Ltd. and Minnesota Valley Testing Labs. 160 p.

46307901 Barnekow, D. (2004) Determination of Atmospheric Concentrations of Sulfuryl Fluoride

Following Fumigation of a Mill Using Profume - UK 2000: Summary Report. Project Number: GH/C/5732, GHE/P/9903, 000377. Unpublished study prepared by Dow Agrosciences LLC and Minnesota Valley Testing Labs and Dowelanco Ltd. 125 p.

47164501 Schols, E.; van Putten, E. (2007) The Dispersal of Fumigants around Ocean Shipping

Containers. Project Number: 609021041/2007, M/609021. Unpublished study prepared by National Institute of Public Health. 67 p.

36 of 50

SUBMITTED EFFECTS STUDIES: MRID 00043314 Dow Chemical Company (1959) Toxicological studies with Vikane (sulfuryl fluoride).

Accession number 104918-A. Dow Chemical, Midland, MI. 41769101 Nitschke, KD; Quast, JF. (1990) Sulfuryl fluoride acute inhalation LC50 – mice. Study

Number K-016399-031, Project Number 1-0754 Prepared by Health/Environmental Services, Dow Chemical, Midland, MI. Sponsored by DowElanco, Indianapolis, IN.

37 of 50

Attachment A

Sulfuryl Fluoride Air Monitoring Data from California Air Resources Board

38 of 50

Figure A-1. Sulfuryl fluoride air monitoring results during 81,000 cubic-foot house fumigation at Grass Valley, CA.

39 of 50

Figure A-2. Sulfuryl fluoride air monitoring results during 45,000 cubic-foot house fumigation at Loomis, CA.

40 of 50

41 of 50

Attachment B

Preliminary PERFUM Modeling for Sulfuryl Fluoride Impacts on Outdoor Air Quality From Treatment in Buildings and Railcars

Table B-1. Emissions profile for sulfuryl fluoride treatment scenarios Exponential Emissions Decay, Multiple Source, 0.05 AXR, Passive Aeration, No Stack

8 lb/1000ft3

Exponential ExponentialHour C (g/m3) ER (ug/m2-s) ER (ug/m2-s)

0 128.151 121.90 8996 132292 115.95 17552 258123 110.30 25692 377824 104.92 33434 491685 99.80 40799 599996 94.93 47805 703027 90.30 38810 570738 85.90 30253 444899 81.71 22113 32519

10 77.73 14371 2113311 73.94 7006 1030312 70.33 8996 1322913 66.90 17552 2581214 63.64 25692 3778215 60.53 33434 4916816 57.58 40799 5999917 54.77 47805 7030218 52.10 38810 5707319 49.56 30253 4448920 47.14 22113 3251921 44.84 14371 2113322 42.66 7006 1030323 40.58 0 024 38.60 0 0

5,000 ft3 10,000 ft36hr, multiple release 6hr, multiple release

Equations: Co = AR / 1000 x 453.59 x 35.315 ER = Co x V x [exp{-AXR x t1} - exp{-AXR x t2}] x 1,000,000 / A / 3600 where ER Flux rate for area source (μg/m2-s) Co initial concentration (g/m3) V volume of building (m3) AXR air exchange rate (hr-1) t1, t2 time 1 and time 2 (hr) A area of building (m2) AR application rate (lbs/1000 ft3) Dur duration of release (6 hrs)

42 of 50

Exponential Emissions Decay, Single Source, 0.1 AXR, Passive Aeration, No Stack 8 lb/1000ft3

Exponential Exponential Exponential Exponential Exponential Exponential Exponential ExponentialHour C (g/m3) ER (ug/m2-s) ER (ug/m2-s) ER (ug/m2-s) ER (ug/m2-s) ER (ug/m2-s) ER (ug/m2-s) ER (ug/m2-s) ER (ug/m2-s)

0 128.151 115.95 10325 12390 17552 25812 25812 25812 77437 774372 104.92 9342 11211 15882 23356 23356 23356 70068 700683 94.93 8453 10144 14371 21133 21133 21133 63400 634004 85.90 7649 9179 13003 19122 19122 19122 57367 573675 77.73 6921 8305 11766 17303 17303 17303 51908 519086 70.33 6262 7515 10646 15656 15656 15656 46968 46968

6hr, single release6hr, single release 6hr, single release6hr, single release6hr, single release6hr, single release 6hr, single release 6hr, single release1,000 ft3 2,000 ft3 5,000 ft3 10,000 ft3 25,000 ft3 50,000 ft3 100,000 ft3 250,000 ft3

8 lb/1000ft3

Exponential Exponential Exponential Exponential Exponential ExponentialHour C (g/m3) ER (ug/m2-s) ER (ug/m2-s) ER (ug/m2-s) ER (ug/m2-s) ER (ug/m2-s) ER (ug/m2-s)

0 128.151 115.95 77437 77437 77437 103249 103249 1032492 104.92 70068 70068 70068 93424 93424 934243 94.93 63400 63400 63400 84533 84533 845334 85.90 57367 57367 57367 76489 76489 764895 77.73 51908 51908 51908 69210 69210 692106 70.33 46968 46968 46968 62624 62624 62624

6hr release 6hr release6hr release6hr release 6hr release6hr release7,500,000 ft3 10,000,000 ft3500,000 ft3 750,000 ft3 1,000,000 ft3 2,500,000 ft3


43 of 50

Exponential Emissions Decay, Single Source, 1.0 AXR, Passive Aeration, No Stack 8 lb/1000ft3

Exponential Exponential Exponential Exponential Exponential Exponential Exponential ExponentialHour C (g/m3) ER (ug/m2-s) ER (ug/m2-s) ER (ug/m2-s) ER (ug/m2-s) ER (ug/m2-s) ER (ug/m2-s) ER (ug/m2-s) ER (ug/m2-s)

0 128.151 47.14 68584 82300 116592 171459 171459 171459 514378 5143782 17.34 25231 30277 42892 63076 63076 63076 189229 1892293 6.38 9282 11138 15779 23204 23204 23204 69613 696134 2.35 3415 4097 5805 8536 8536 8536 25609 256095 0.86 1256 1507 2135 3140 3140 3140 9421 94216 0.32 462 555 786 1155 1155 1155 3466 3466

1,000 ft3 2,000 ft3 5,000 ft3 10,000 ft3 25,000 ft3 50,000 ft3 100,000 ft3 250,000 ft36hr, single release 6hr, single release 6hr, single release 6hr, single release 6hr, single release 6hr, single release 6hr, single release 6hr, single release

8 lb/1000ft3

Exponential Exponential Exponential Exponential Exponential ExponentialHour C (g/m3) ER (ug/m2-s) ER (ug/m2-s) ER (ug/m2-s) ER (ug/m2-s) ER (ug/m2-s) ER (ug/m2-s)

0 128.151 47.14 514378 514378 685837 685837 685837 6858372 17.34 189229 189229 252305 252305 252305 2523053 6.38 69613 69613 92818 92818 92818 928184 2.35 25609 25609 34146 34146 34146 341465 0.86 9421 9421 12562 12562 12562 125626 0.32 3466 3466 4621 4621 4621 4621

500,000 ft3 1,000,000 ft3 2,500,000 ft3 5,000,000 ft3 7,500,000 ft3 10,000,000 ft36hr release 6hr release 6hr release 6hr release 6hr release 6hr release


44 of 50

Exponential Emissions Decay, Single Source, 1.0 AXR, Active Aeration, 5 ft. Vertical Portable Stack and Exponential Emissions Decay, Single Source, 1.0 AXR, Active Aeration, 3 ft. Horizontal Portable Stack

8 lb/1000ft3

Exponential Exponential Exponential Exponential Exponential Exponential Exponential ExponentialHour C (g/m3) ER (g/s) ER (g/s) ER (g/s) ER (g/s) ER (g/s) ER (g/s) ER (g/s) ER (g/s)

0 128.151 47.14 0.637 1.274 3.186 6.37 15.93 31.86 63.72 159.292 17.34 0.234 0.469 1.172 2.34 5.86 11.72 23.44 58.603 6.38 0.086 0.172 0.431 0.86 2.16 4.31 8.62 21.564 2.35 0.032 0.063 0.159 0.32 0.79 1.59 3.17 7.935 0.86 0.012 0.023 0.058 0.12 0.29 0.58 1.17 2.926 0.32 0.004 0.009 0.021 0.04 0.11 0.21 0.43 1.07

6hr, single release6hr, single release6hr, single release6hr, single release6hr, single release6hr, single release6hr, single release 6hr, single release1,000 ft3 2,000 ft3 5,000 ft3 10,000 ft3 25,000 ft3 50,000 ft3 100,000 ft3 250,000 ft3

8 lb/1000ft3

Exponential Exponential Exponential Exponential Exponential Exponential ExponentialHour C (g/m3) ER (g/s) ER (g/s) ER (g/s) ER (g/s) ER (g/s) ER (g/s) ER (g/s)

0 128.151 47.14 318.58 477.87 637.16 1593 3186 4779 63722 17.34 117.20 175.80 234.40 586 1172 1758 23443 6.38 43.12 64.67 86.23 216 431 647 8624 2.35 15.86 23.79 31.72 79 159 238 3175 0.86 5.84 8.75 11.67 29 58 88 1176 0.32 2.15 3.22 4.29 11 21 32 43

6hr release 6hr release6hr release6hr release6hr release 6hr release6hr release5,000,000 ft3 7,500,000 ft3 10,000,000 ft3500,000 ft3 750,000 ft3 1,000,000 ft3 2,500,000 ft3

Equations: Co = AR / 1000 x 453.59 x 35.315 ER = Co x V x [exp{-AXR x t1} - exp{-AXR x t2}] / 3600 where ER Emission rate for point source (g/s) Co initial concentration (g/m3) V volume of building (m3) AXR air exchange rate (hr-1) t1, t2 time 1 and time 2 (hr) AR application rate (lbs/1000 ft3) Dur duration of release (6 hrs)

45 of 50

46 of 50

Table B-2. File log matrix for PERFUM runs.


Structure Volume

(ft.3)

Constant, Multiple Source Emissions, 0.05

AXR, Passive

Aeration, No Stack

Exponential Single Source

Emissions, 0.1 AXR, Passive Aeration, No

Stack

Exponential Single Source Emissions,

1.0 AXR, Passive Aeration, No Stack

Exponential Single Source Emissions, 1.0 AXR, Active Aeration, 5 ft.

Portable Vertical Stack

Exponential Single Source Emissions, 1.0 AXR, Active Aeration, 3 ft. Horizontal Portable

Stack 1,000 8lbaerns10_1000e4 8lbaerns01_1000e4 8lbaerp10_1000em4 8lbaerp10_1000e4 2,000 8lbaerns10_2000e4 8lbaerns01_2000e4 8lbaerp10_2000em4 8lbaerp10_2000e4 5,000 8lbtmt10000c4 8lbaerns10_5000e4 8lbaerns01_5000e4 8lbaerp10_5000em4 8lbaerp10_5000e4

10,000 8lbtmt5000c4 8lbaerns10_10000e4 8lbaerns01_10000e4 8lbaerp10_10000em4 8lbaerp10_10000e4 25,000 8lbaerns10_25000e4 8lbaerns01_25000e4 8lbaerp10_25000em4 8lbaerp10_25000e4 50,000 8lbaerns10_50000e4 8lbaerns01_50000e4 8lbaerp10_50000em4 8lbaerp10_50000e4

100,000 8lbaerns10_100000e4 8lbaerns01_100000e4 8lbaerp10_100000em4 8lbaerp10_750000e4 250,000 8lbaerns10_250000e4 8lbaerns01_250000e4 8lbaerp10_250000em4 8lbaerp10_100000e4 500,000 8lbaerns10_500000e4 8lbaerns01_500000e4 8lbaerp10_500000em4 8lbaerp10_250000e4 750,000 8lbaerns10_750000e4 8lbaerns01_750000e4 8lbaerp10_750000em4 8lbaerp10_500000e4

1,000,000 8lbaerns10_1000000e4 8lbaerns01_1000000e4 8lbaerp10_1000000em4 8lbaerp10_1000000e4 2,500,000 8lbaerns10_2500000e4 8lbaerns01_2500000e4 8lbaerp10_2500000em4 8lbaerp10_2500000e4 5,000,000 8lbaerns10_5000000e4 8lbaerns01_5000000e4 8lbaerp10_5000000em4 8lbaerp10_5000000e4 7,500,000 8lbaerns10_7500000e4 8lbaerns01_7500000e4 8lbaerp10_7500000em4 8lbaerp10_7500000e4

10,000,000 8lbaerns10_10000000e4 8lbaerns01_10000000e4 8lbaerp10_10000000em4 8lbaerp10_10000000e4 1 All nomenclature shown refers to naming convention of PERFUM input files (.per) and PERFUM output files (.out). 2 All PERFUM input and output files are available electronically. 3 PERFUM2 output processing at target concentration of 278,303.6 μg/m3 based on the level of concern for acute endangered species from the most sensitive rat

inhalation LC50 value(0.1 x 2,793,036 μg/m3 or 642 ppm) per MRID No. 41769101. 4 PERFUM2 input based on Methyl Bromide indoor fumigation modeling following exponential decay box model emissions profile at an application rate of 8

lb./1000 ft.3, and specified air exchange rate (AXR) of treated buildings using Bradenton, FL meteorological data per Dawson, 2008. 5 PERFUM2 input release parameters (e.g., stack diameters and flow velocities) consistent with Dawson, 2008 for each scenario. 6 Modeling at 5,000 ft.3 and 10,000 ft.3 representative of railcar and cargo hold structure sizes of 5,238 ft.3 – 6646 ft.3 per CSX website

(http://www.csx.com/?fuseaction=customers.ag_cars-detail&i=1759). Multiple sources accounted for per Dawson, 2008.

47 of 50

Attachment C

Tables of Justification for Environmental Fate and Ecological Data Requirements

48 of 50

Environmental Fate Data Justifications for Sulfuryl Fluoride Guideline Number: Non-guideline Study Title: Measurement of Henry’s Law Constant

Rationale for Requiring the Data The Henry’s Law Constant of 1.56 atm•m3/mol, calculated by the existing measured vapor pressure (12,087 torr) and solubility in water (1,040 mg/L) normalized to molecular weight, indicates that deposited airborne sulfuryl fluoride residues will not be retained at shallow depths in saturated surfaces for large periods of time. A measured Henry Law Constant value is being requested at this time to confirm the resistance properties of sulfuryl fluoride for deposition in the terrestrial and aquatic environments. Since the spatial scale for aquatic expsosure can be of concern over a global scale given sulfuryl fluoride’s persistent nature in the atmosphere, this data will be used to confirm the Agency’s conclusions regarding the risk for exposure in aquatic environments.

Practical Utility of the Data How will the data be used? This physical-chemical property will be used to characterize sulfuryl fluoride’s potential for exposure in the aquatic environment via atmospheric deposition. How could the data impact the Agency’s future decision-making? Without the requested data, the Agency would assume that there is a risk of concern for sulfuryl fluoride exposure for all aquatic organisms. Therefore, if future endangered species risk assessments are performed without these data, the Agency may have to assume that sulfuryl fluoride residues in air originating from releases from fumigated structures might need to be restricted to a level where bioaccumulation will no longer be of concern. The lack of these data will limit the flexibility the Agency and registrants have in coming into compliance with the Endangered Species Act and could result in use restrictions for sulfuryl fluoride which are unnecessarily severe.

49 of 50

Ecological Effects Data Justifications for Sulfuryl Fluoride Guideline Number: Non-guideline Study Title: Avian Inhalation

Rationale for Requiring the Data Current data suggest that during fumigation of structures (including homes, non-residental structures such as warehouses, construction materials, mills, barns, and vehicles such as automobiles, rail cars and ships), sulfuryl fluoride is released to the outdoor atmosphere during the aeration phase. Preliminary calculations of potential exposure show that sulfuryl fluoride will be present in environmental relevant concentrations that may affect non-target organisms. Since sulfuryl fluoride is highly volatile and is a gas at room temperature and standard pressure, inhalation of vapor following structural fumigation is the major exposure pathway for non-target mammals and birds. Sulfuryl fluoride is highly toxic to mammals via inhalation, and this suggests that the chemical may also be toxic to avian species. In the absence of toxicity data, insufficient information exists to preclude concerns for direct toxic effects to non-target birds.

Practical Utility of the Data How will the data be used? With this study, the Agency will be able to assess risks to endangered and other non-target avian species near release points of sulfuryl fluoride. If the avian inhalation study shows that sulfuryl fluoride exceeds the Agency’s level of concern for federally listed or other terrestrial avian species, the Agency may be able to use this data to mitigate risks. How could the data impact the Agency’s future decision-making? If future endangered species risk assessments are performed without these data, the Agency would assume that sulfuryl fluoride may directly affect endangered avian species. Use of sulfuryl fluoride may need to be restricted in areas where endangered species could be exposed. The lack of these data will limit the flexibility the Agency and registrants have in complying with the Endangered Species Act and could result in use restrictions for sulfuryl fluoride that are unnecessarily severe.

50 of 50

Guideline Number: Non-guideline Study Title: Terrestrial Plant special study

Rationale for Requiring the Data

Current data suggest that during fumigation of structures (including homes, non-residental structures such as warehouses, construction materials, mills, barns, and vehicles such as automobiles, rail cars and ships), sulfuryl fluoride is released to the outdoor atmosphere during the aeration phase. Preliminary calculations of potential exposure show that sulfuryl fluoride will be present in environmental relevant concentrations that may affect non-target organisms. Sulfuryl fluoride has a general mechanism of action that indicates the chemical may have toxicity to plant species, and label language also suggests this compound is highly toxic to plants. No data are available to assess the toxicity of sulfuryl fluoride to vegetation near release points. In the absence of such data, insufficient information exists to preclude concerns for direct toxic effects to non-target plant species.

Practical Utility of the Data How will the data be used? With this study, the Agency will be able to assess risks to endangered and other non-target plants downwind from release points of sulfuryl fluoride. If the terrestrial plant special study shows that sulfuryl fluoride exceeds the Agency’s level of concern for federally-listed or other terrestrial plant species, the Agency may be able to use this data to mitigate risks. How could the data impact the Agency’s future decision-making? If future endangered species risk assessments are performed without these data, the Agency would assume that sulfuryl fluoride may affect endangered terrestrial plant species directly and (endangered species that depend on these plants). Use of sulfuryl fluoride may need to be restricted in areas where endangered species could be exposed. The lack of these data will limit the flexibility the Agency and registrants have in complying with the Endangered Species Act and could result in use restrictions for sulfuryl fluoride that are unnecessarily severe.

Documents

Problem Formulation for thefluoridealert.org/wp-content/uploads/sf-epa.eco-risk.june_.2009.pdf · ecological risk (US EPA, 1993). In this problem formulation, EFED will present the