l~,~tt, r Reiew'~'# ~,ol. ~, pp "~1 to 7~ Pergamon Press [9"4 Prm~ed in Great Brttaln.

PHTHALIC ACID ESTERS IN WATER

M MORtTA. H NAKAMURA and S. MIMURA

Tokyo Metropolitan Laboratory of Medical Science, Hyakunin-cho 3-24-1. Shinjuku-ku Tokyo, Japan

(Received 26 February 1974)

Abstract--Two phthalic acid esters, di(n-butyllphthalate and di (2-ethylhexyl)phthalate, were surveyed in. the river water, well water and city water of Tokyo metropolice area. In the river water these esters were found in the range of 0.4-6-8/~g 1- t The concentration was low in the upper reaches of the stream but increased downstream, giving no seasonal variation. The esters were not found in the well water examined. In the household tap water they were contained in the range of 1.2-3.3/~g l- ~ while in the raw water of water supply they were contained in the range of 1.9-8-2/~g 1- L. Results of jar test revealed that these esters were efficiently removed from water by using activated carbon or aluminium sulphate.

,MATERIALS A N D M E T H O D S

Chemical reayems

Ether--This reagent from Wako Chemicals was dis- tilled twice before use. Hydrochloric acid--This re- agent was distilled. Sodium sulphate--This reagent was rinsed with distilled ether and dried on a hot plate at about 200~C. Standard di(n-butyl)phthalate and di(2-ethylhexyl)phthalate--These were guaranteed rea- gents from Wako Chemicals.

Instruments

Gas chromatography--Shimazu GC 5AP. Infrared spectrometer--Hitachi EPI-G3. Mass spectrometer

- -Sh imazu Gaschromatography Mass Spectrometer LKD-9000.

Sampling size and procedure

River water. The Tama River is one of the large rivers to flow into Tokyo bay. Rapid and progressive pollution has taken place in the past 20 years due to population increases. The pollution is caused by the domestic sewage and wastes from many small factories. The water supply of Tokyo comes from this river. Figure 1 shows the sampling points on the river.

Well water. Five shallow wells of less than 25 m, four in downtown Tokyo and one in the suburbs, were sam- pled.

City water. Samples were obtained from the water supply and from household taps.

........ : ~ - ~ f ~ =~-~Korernoso ) ~ ~JL ~J ~"

"'~" .. ~'"!."'" ~ H o n e d o kfn ".. !,

o. .... ,o .-.

Fig. 1. 781

-',2 M. )~IoRtT~. H. NAKAMt RA and S. NIIMLRA

Qutmtitaticc tltkl[v.~is

The ~,amplcs ~crc prepared for gas chromat- ograph.' using a modification of the procedure b`' Katase and Han`'a {197_.21. Water samples f500ml) adjusted to pH 2*) ~̀ ' ith HC1 were extracted three times with 350 ml of ether. The ether la',er was collected and dried with anhydrous sodium sulphate by leaving it to stand o~ernight. The ether extracts ~erc collected b3 decantation and the residual sodium sulphate "as rinsed ~ ith 50 ml of ether. The rinsed ether ,,,,as added to the mother liquid and lbllo`'`'ed by the condensation to a volume of 51X)/.d with Kunderna-Danish con- denser.

Estimatiot~. Di{n-butyl)phthalate and di(2-ethylhex- ~l)phthalate were determined using dual column GLC. The conditions were as follows: Detector--Flame ioni- zation detector (270 CL H, rio`'`" 50 ml min- ~: air flow 1.01 ra in - t , sensitivity 10 z range I (or sensitivity 103 range 4t. Carrier gas N, . flow 60 ml min - ~.

Column 1. 0V-1711"5",,1 on Shimalite W (80-100) temp. 210 C.

Column 2. SE 30t5",,) on Shimalite W (80-100} temp. 230 C.

Repeated quantitative analysis of the standard soltt- tion containing 101lg 1-~ of di(n-butyl)phthalatc and I0 ltg I- t of di{ 2-cthylhcxyIIphthalate showed that the mean recovery' was 97 per cent and the SD. was 10 per cent in both compounds.

Remocal test

Elimination of di(n-butyllphthalate from water was studied in jar test. After the addition of the reagent {activated carbon or aluminium sulphate) the sample water was stirred at the rate of 150 rev rain- t for 30 rain and then left to settle for 12 h. The supernatant was analysed by gas chromatography. The carbon used was a powdered activated carbon obtained from Kanto Chemicals. Aluminium sulphate and the calcu- lated cqttiwflent of sodium carbonate were used for coagulation.

R ES U LTS

hlcntification

Two main peaks were commonly observed in the gas chromatogram of the ether extracts from the river water and these were assumed to correspond to di(n- butyl)phthalate and di(2-ethylhexyl)phthalate. A sample extracted with ether from 1001. water of the Tama river was fractionated with GLC (column I). Liquid condensed in the capillary equipped at the out- let of the column was pressed with KBr powder to make a micro disc for infrared spectroscopy. Fractions with the same retention time which corresponded to

that of di( n-but? l~phthalate and di(2-ethylhex? t!phtha- late showed quite similar infrared spectra to those of the authentic samples.

,~,[ass fraqmemation

Ether extracts from several samples were checked with gas chromatograph~-mass spectroscopy, Gas chromatogram of cleaned water at Kanamachi water supply is shown in Fig. 2. Mass fragmentations of peaks A and B are almost identical to those of di(n- butyliphthalate and di(2-ethylhexyllphthalate, respect- ively, suggesting that these peaks consisted of almost pure di(n-but.~llphthalate and di(2-ethylhexyl)phtha- late. Fragment peaks ascribable to other materials had a very weak intensity even at the foot of these peaks (peak A and B).

Therefore it was concluded that other materials were not observed near these peaks by the total ion detector. The specific character of the flame ionization detector resembled that of total ionization detector in sensi- tivity and so it is reasonable to quantify these phtha- lares with their peak areas in the gas chromatogram using flame ionization detector neglecting the overlap of other materials.

In the sample of river water (Fig. 31. these peaks are a little contaminated. In the mass spectrum of peak B, weakly contaminated fragment peaks are observed at 199, 114, 85 (me- t ) . These peaks, however, seems to give at most 5 per cent overestimation even if the con- tamination error is neglected. Though this kind of error emerges in the down stream samples, the overes- timation seemed to be below 10 per cent.

Phthalic acid esters concentration in the river water

The results of samples obtained in the Tama River are listed along with other chemical and biological in- dexes in Tables 1 and 2. Di{n-butyl)phthalate and di(2- ethylhexyl)phthalate could be detected in the most upper reaches of the stream where no E. coli were found. The pollution of the river by phthalic acid esters was not clearly correlated to several water quality in- dexes such as chemical oxygen demand, ammonia con- centration, and the number of E. coli or micro- organisms. Katase et al. (1972) reported that the di(n- butyljphthalate concentration in this river ranged from l to 350/.~gl-t and that the maximum level (350/.~g 1-t) was observed in the river sludge in sum- mer. Since di(n-butyllphthalate is sparingly soluble in water, it may have a higher concentration in sludge than in water.

Phthalic acid esters in water 7~

P e o k ~, (dl ( n - ioul-yl) p~'t'holote)

PeokB h I . (d~'~2-et y -

Io,9

Peok

III [ . I ~, : ~ ! 50 ~00 t50 250 300

149

167

205 225

I[ , 20(3

Peok 8

i,, H ,, ,, t I , 50 tOO k50 200 300

Fig. 2.

279

, I 25O

Phtfialic acid esters concentrution in well water

Neither di(n-butyl)phthalate nor di(2-ethylhexyl)ph- thalate was detected in well water (Table 3). The detec- tion limits were 0'2,ug I- l and 0"5 #g 1-1 for di(n- butyl)phthalate and di(2-ethylhexyl)phthalate, respec- tively.

Phthalic acid esters concentration in city water and raw

water

Phthalic acid esters concentration of city water was measured at three points: the raw water at the intake to a filtration bed, cleaned water after coagulation and tap water delivered in the water supply pipe (Table 3). The raw water contained di(n-butyljphthalate and di(2- ethylhexyl)phthalate in the range of 2-8 and 2- 5/ag 1- t respectively, with mean values of 4-5/ag 1- t for di(n-butyl)phthalate and 2-7 #g I - t for di(2-ethyl- hexyl)phthalate. The cleaned water showed a little lower concentration of di(n-butyljphthalate (3'5 #g I- t) and di(2-ethylhexyl)phthalate (l.8,ug I- ~) and the tap

water showed further lower value (di(n-butyl)phthalate 2-3/ag 1- t di(2-ethylhexyl)phthalate 1.8/~g 1- t). These facts suggest the effectiveness ofcoagulation and chlor- ine addition for the elimination of phthalic acid esters.

Remocal process

The results of jar tests are shown in Table 4. By stir- ring with activated carbon, di(n-butyl)phthalate and di(2-ethylhexyl)phthalate were eliminated from water. An effective and practical process was the conventional coagulation process using aluminium sulphate. In the presence of suspended matter the elimination of the phthalic acid esters was increased.

DISCUSSION

Di(2-ethylhexyllphthalate and di(n-butyl)phthalate have been mainly used as placticizers in polyvinylch- loride resins and volatilization from the resin is known to be temperature dependent. Because their vapour

784 M. MORITA. H. NAKAMLRA and S. Mt~.tL R.,,

Peak A

Peak B

111 5O

I

I00

149

I i i t

~50

Peak [A

205 223 278

~l I ! , F 200 250 300

I I

50 IO0

149

r50

Fig. 3.

Peak B 167

279

L ! I 200 250 300

pressure and solubility increase with temperature, their discharge into the environment may be expected to be large in summer and small in winter. However, analy- sis did not show any seasonal variations. This may sug- gest that the esters are discharged into the environ- ment not only from plastics.

The ratio di(2-ethylhexyl)phthalate/di(n-butyl)- phthalate varied in the range of 0-6-4.2 with a mean value of 1.5 in the Tama river. This ratio has been approxi- mately 4 in industrial production in Japan in the last few years. It therefore seems that emission of di(n- butyl)phthalate into the environment is greater than that of di(2-ethylhexyl)phthalate. This may be due to differences in the uses of di(n-butyl)phthalate and di(2- ethylhexyl)phthalate. In contrast to the use of di(2-eth- ylhexyl)phthalate as a placticizer, an appreciable por- tion of di(n-butyl)phthalate has been consumed as a solvent in paints, adhesives and insecticides in Japan. In North America, di(2-ethylhexyl)phthalate was detected at a concentration of 0-88-1"9.ug 1- t (Charles

River, Boston: Hites and Biemann, 1972) and 4.9 ,ug 1- 1 (Missouri River: Mayer et al, 1972), whereas dibutylphthalate was detected at a concentration of 0.09 #g I- t (Missouri River). The ratio di(2-ethylhex- yl)phthalate/di(n-butyl)phthalate seems to be large in North America compared with that in Japan. The dif- ference may be attributable to differences in the use of these esters in the two countries.

It is interesting to note that phthalic acid esters are absent from well water even in the centre of Tokyo but present in water in the most upper reaches of the river in a woodland brook. They have been reported to be present in the matter of soil (Cifrulak, 1969) and in the fulvic acid from soil (Ogner and Schnitzer, 1970). Phthalic acid esters dissolved or suspended in the water may have been trapped in the soil during leach- ing, resulting a phthalate free water. Similar pheno- mena have been observed with polychlorinated biphenyls (PCBs); no PCBs were detectable in the well water in the vicinity of a factory which was held re-

Tab

le

I. [)

i01-

buty

l)ld

ltha

latc

and

di(

2-cl

hylh

exyl

)l~

htha

lalc

in

the

Tam

u R

iver

(Ji

mtm

ly 1

9731

Wat

er t

emp.

Si

te

(~C)

l)i(

l~-b

utyl

)-

CO

l)

CI

Nil

3

Sli

mc

phth

alat

e (p

pm)

(ppm

) (p

pm)

(rag

100

ml

I) (I

tg I

- I)

l)i(

2-ct

hylh

cxyl

) i~

htha

latc

(tl

g I

~)

.~tll

|] {i

t,g I

~)

Rat

io*

V (1

) Il

ikaw

a 2

(21

Saw

ado

3 (3

) H

igas

hiak

ikaw

a 3

(4)

llam

ura

5

(5)

tlin

o 7

(6)

Scki

do

7 (7

) K

orem

asa

7"

(8)

Ka

w;.t

har~

l 7

191

Sui

do

6 (1

0) M

aru

ko

7

(I I

) D

aish

i'~

7 (1

2) I Im

~eth

c["

7

0-5

4-9

1.0

25.6

0"

73

0"9

7.0

1.0

23-6

1-

53

0.8

7.0

1"0

20'8

(;"

71

1.5

9"6

1"3

26"1

2"

76

3"8

2%9

2' 1

32

'5

1"(,1

6 4-

7 19

'1

2"3

25'2

1"

06

3'6

1% 1

2"

5 27

"9

1"(1

9 4'

9 24

"5

2"6

33'4

1-

38

6-6

19-7

1"

3 24

"3

I'10

6-

5 25

'2

3'2

24"3

3"

1 I

9"4

7430

3"

2 15

67

3"14

10

"6

1150

0 3"

3 22

(:,4

2"75

1.3

(1,9

1,

8 2.

6 4.

4 1,

9 2,

0 3.

8 2.

4 3,

2 3.

7 3,

5

2"0

2'4

2"5

54

5"5

3-O

3"

I 52

3"

5 6.

3 (r

8 6'

3

].5

_3. 5

t)'9

4"

1

1'8

2"9

2-2

Io

1,2

1.3

~7

* l)

i(2-

ethy

lhex

yl)p

htha

latc

/di(

ll-b

u t y

l)fd

uhal

ate.

"t"

Sea

wat

er i

s m

ixed

m t

hese

are

as.

2

7S6 ~,{. MORITA. H. NAKAMLRA and S. MEXlLR.',

Table 2. Di0z-but,~l)phthalate and di 2-eth?lhexvl)phthalate in the Tama Ri;er {June f973}

Dil n-but? I) T.C.* MPN+ COD$ phthalate

IN ml-*l (N 100ml- 1l {ppm) I.,tgI-*l

Di( 2-eth~lhex?ll- phthalate (#g 1- ~)

Hikawa 22 790 3.8 0.67 Sawado 510 6000 3.4 0 5 I Higashiakikawa 420 2200 36 0-38 Hamura 1300 1300 4.0 1-93 Hino 33.000 79,000 5-9 2.43 Koremasa 9400 33.000 8.2 3.47 Sekido 31,000 13,000 9.2 198 Tamagawara 34,000 79,000 88 t.95 Suido 13.000 130,000 7. I 5.61 Maruko 180,000 320.000 14-0 2-44 Dais,hi 170,000 490,000 16"0 2-99 Ha neda 180,000 490,000 16"9 1.98

1.0 0-5 0.8 2-3 1.6

2 l 0.9 2.6 2.9 3.7 6.8

* Total colonies (37:C, 24 h). t Most probable number (E. coli) (37°C, 48 h). , + Potassium permanganate consumed (100°C, 5 rain).

sponsib le for the pol lu t ion of the water in the sur-

round ing area (Tsuchiya, private communica t ion) . The concen t r a t i on in the river water o f ph tha l ic acid

esters is the result o f equi l ibr ium be tween their intro-

duc t ion and removal from the water. There are three

likely routes of c o n t a m i n a t i o n : (1) from a tmosphe re (2) from domes t i c sewage (3) from factory waste water .

The presence of the esters in the upper reaches of the

Table 3. Di(n-butyl)phthalate and di(2-ethylhexyl)-phthalate in well water and supplied water

Sample

Di(n-butyl)- Di(2-ethylhexyl)- phthalate phthalate (/~g 1 - ~ ) (,ug 1 - ~)

Well water (five samples) - -* - -*

Supplied water H water supply raw 4.31 l-9

purl. 3-22 25 tap 1-43 1.2

A water supply raw 8 16 4.7 pure 2.04 1.3 tap 2 l l 1.2

K water supply raw 4.87 2.4 pure 3.23 1.2 tap 2.57 1.8

N water supply raw 3.90 2.5 pure 550 2.2 tap 2.57 1.8

K' water supply raw 2.74 l-7 purf. 14.27t 3.1 tap 3.31 1.8

H water intake site raw 3.04 2.7

Mean value of raw water 4.50 2.7

Mean value of purl. water 3.50 lS

Mean value of tap water 2.34 1.3

* - - under the detection limit. t This high value of di(n-butyl)phthalate may be attributed to the elution from

the new vinylchloride resin which was used as a pipe to conduct the purified water to the inspection laboratory in the water supply.

Phthalic acid esters in water

Table 4. Purification with activated carbon and aluminium sulphate

-zS7

I I~ Reagent: poundered actbated carbon

Carbon Esters conch cohen

Water: phthalate esters added tit} ~ater

Dit n-bu t',l Ipht halate Di~ 2-et h? lhex 5 hphthalate Residual Removal Residual Removal (~*g 1 - ~1 ~",,J ~.ug 1 - ;1 (',,~

50 50 16-4 65 30-3 -~} 50 100 14.1 ~2 I 1-~ 7~,

I(~0 50 155 84 29.: 70 1{}O 100 14-8 85 144 86

12} Reagent: aluminium sulphate Water: phthalate esters added city water

Di{n-but)l)phthalate Di{ 2-eth~lhexyl }phthaktte Esters conch Alum conch Residual Removal Residual Removal

(l~gl-l) Imgl-t) {.ugl-~) I",,) ~,ugl I} (,,,) 50 25 468 6 90 s2 50 50 347 31 45 g l

I{}0 25 645 36 17-0 83 100 50 55-6 44 s3 92

{ 3 } Reagent: ahLminium sulphate Water: phthalate esters added river water* Di{n-butyllphthalate Dil 2-eth) Ihex?ltphthalJ te

Esters conch Alum conch Residual Remo',al Residual Removal (#gl- l) [llgl-l) (#gl-I) ("i,) (#gl '1 {",)

25 25 15"6 38 1'9 92 25 50 5"8 77 0"9 96 5t) 25 23"4 53 3"S 92 50 51) 10"5 79 1"5 97

* Suspended matters arc present in this water sample.

rivcr suggests that they may be carricd through the atmosphcre. Part also come from domestic sewage, sincc the cstcrs arc present in most of the sewage exam- ined. The third route may give temporary but high contamination. An abnormally high contamination, over 10,ug 1-~, has been reported in the same river (Katase and Hanya, 1972). This kind or pollution can be attributed to trade wastes. The relative importance of these three routes is not known.

In regard to the disappearance of phthalic acid esters in river water, the following three processes probably occur: (11 sedimentation (2) uptake by aquatic animals and plants (31 biodegradation. Part of the esters in water settle to the bottom with suspending materials. Indeed. the bottom muds of this river contained several mg kg- t of di (n-butyl)phthalate and di(2-eth- ylhexyl)phthalate (Nakamura, unpublished work). The accumulation of these esters by aquatic animals is known in several kinds of fish (Mayer et al., 1972t. It is also known that they can be metabolized in fish (Stalling et al., t973). Therefore aquatic animals and plants may play a significant role in the removal of these compounds from river water.

Biodegradation of phthalic acid esters by bacteria and fungi is known to occur. Experiments by Saeger

and Tucker 11973) indicate biodcgradabilitics of 70-78 per cent of di(2-ethylhexyl)phthalate compared to > 99 per ccnt for linear alkylbenzenesulphonate in semi- continuous actiwtted sludge test. Biodegradation of di(2-butyl)phthaktte and di(2-ethylhex?l)phthalate can be expected in rivers, though no report on this has been made. We attempted to detect phthalic acid which was a probable break down product of phthalic acid esters in an aqueous system, without success, although the detection limit was 1/~g 1-~. Assuming that di(2-ethylhexyl)phthalate probably decomposes more slowly than di(n-butyljphthalate, the ratio di(2- ethylhexyl)phthalate/di(n-butyllphthalate can be expected to increase downstream. Such a tendency, however, could not be demonstrated in the river we examined.

Using 100mg of powdered activated carbon in 1 litre of water, the initial concentration of 100 g~g 1- of dil2-ethylhexyl)phthalate and di(n-butyl)phthalate was reduced to 15 F~gl- 1. Aluminium hydroxide adsorbs and therefore effectively eliminates di(2-ethyl- hexyl)phthalate dissolved in water. The presence of suspending substances remarkably improved the removal. Di(,-butyl)phthalate was more difficult to remove from water than di(2-ethylhexyl)phthalate

7SS M. MORtTA. [-[. NAKAMt RA and S. Nl[xu_ ~A

o~ ing to its higher solubil i ty and polari ty. !Solubili ty

in ~ atcr : di~ Jz-buty l tphthata te 28 mg 1- t. dit 2--ethylhex-

yl~phthalate 1~ mg 1- ~ at 26:CI.

Ackrro;,.'le,'.lqe,w~zt--The authors wish to express their appre- ciation to Dr. Gen Ohi for his constructive advice.

REFERENCES

Cifrulak S. D. t1969) Spectroscopic e~idence of phthalates in soil organic matter. Soil Sei. 11}7, 63-69.

Hires R. A. and Biemann K. 119721 Water pollution: organic compounds in the Charles River, Boston. Science, N .Y 178, I58.

Katase T. and Hanya T. I 1'-)72~ On the anal>sis of phthalic acid esters lin Japanese~. J. l, Vdter dtzd L!,uste 14. 1',';-24.

Ma?cr jun. F. L.. Stalling D. L. and Johnson J. L. 11972~ Phthalic acid esters a> environmental contaminants. .Vuture. Lo~zd. 238, 4l 1-413.

Ogner G. and Schnitzer M. ~ 1970t Humic Substances: Ful- vic acid-dialk~l phtha[ate complexes and their role in pol- lution. Sciem.'e, .\'.E 170, 317-318.

Saeger V. E. and Tucker E. S. {19731 Regional Technical Conference of the Societ? of Plastics Engineering.

Stalling D. L.. Hogon J. W. and Johnson J. L.(t9731 Phtha- late ester rcsiducs--their metabolism and analysis m tish. E;~viromnemul Heul'rh Perspective,, E.',:p. Issue No. 3. 159-174.