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Journal of Environmental Management 163 (2015) 125e133

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Journal of Environmental Management

journal homepage: www.elsevier .com/locate/ jenvman

Review

Perspectives of phytoremediation using water hyacinth for removal ofheavy metals, organic and inorganic pollutants in wastewater

Shahabaldin Rezania a, b, Mohanadoss Ponraj c, *, Amirreza Talaiekhozani a, e,Shaza Eva Mohamad d, **, Mohd Fadhil Md Din a, b, Shazwin Mat Taib b,Farzaneh Sabbagh f, Fadzlin Md Sairan a, b

a Centre for Environmental Sustainability and Water Security (IPASA), Research Institute for Sustainable Environment, Universiti Teknologi Malaysia (UTM),81310 Johor Bahru, Malaysiab Department of Environmental Engineering, Faculty of Civil Engineering, Universiti Teknologi Malaysia (UTM), 81310 Johor, Malaysiac Construction Research Center (CRC), Institute for Smart Infrastructure and Innovation Construction (ISIIC), Faculty of Civil Engineering, UniversitiTeknologi Malaysia (UTM), 81310 Johor Bahru, Malaysiad Malaysia Japan International Institute of Technology, UTM, Kuala Lumpur, Malaysiae Department of Civil Engineering, Jami Institute of Technology, Isfahan, Iranf Faculty of Chemical Engineering, Bioprocess Engineering, Universiti Teknologi Malaysia (UTM), 81310 Johor Bahru, Malaysia

a r t i c l e i n f o

Article history:Received 5 May 2015Received in revised form13 August 2015Accepted 14 August 2015Available online xxx

Keywords:Water hyacinthWastewater treatmentPollutant removalPytotechnology

* Corresponding author.** Corresponding author.

E-mail addresses: goldking1977@gmail.com (M(S.E. Mohamad).

http://dx.doi.org/10.1016/j.jenvman.2015.08.0180301-4797/© 2015 Elsevier Ltd. All rights reserved.

a b s t r a c t

The development of eco-friendly and efficient technologies for treating wastewater is one of theattractive research area. Phytoremediation is considered to be a possible method for the removal ofpollutants present in wastewater and recognized as a better green remediation technology. Nowadaysthe focus is to look for a sustainable approach in developing wastewater treatment capability. Waterhyacinth is one of the ancient technology that has been still used in the modern era. Although, manypapers in relation to wastewater treatment using water hyacinth have been published, recently removalof organic, inorganic and heavy metal have not been reviewed extensively. The main objective of thispaper is to review the possibility of using water hyacinth for the removal of pollutants present indifferent types of wastewater. Water hyacinth is although reported to be as one of the most problematicplants worldwide due to its uncontrollable growth in water bodies but its quest for nutrient absorptionhas provided way for its usage in phytoremediation, along with the combination of herbicidal control,integratated biological control and watershed management controlling nutrient supply to control itsgrowth. Moreover as a part of solving wastewater treatment problems in urban or industrial areas usingthis plant, a large number of useful byproducts can be developed like animal and fish feed, power plantenergy (briquette), ethanol, biogas, composting and fiber board making. In focus to the future aspects ofphytoremediation, the utilization of invasive plants in pollution abatement phytotechnologies cancertainly assist for their sustainable management in treating waste water.

© 2015 Elsevier Ltd. All rights reserved.

Contents

1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22. Water hyacinth . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2

2.1. Morphology and habitat . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 23. Application of aquatic plants in wastewater treatment for the removal of pollutants . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3

3.1. Removal of heavy metals using water hyacinth . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 53.2. Removal of inorganic and organic compound . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5

. Ponraj), shaza@utm.my

S. Rezania et al. / Journal of Environmental Management 163 (2015) 125e133126

4. Control of water hyacinth growth . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 65. Future perspectives of phytotechnology/phytoremediation in pollution control . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 76. conclusion . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7

Acknowledgment . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8References . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8

1. Introduction

Eichhornia crassipes also known as water hyacinth has gainedsignificant attention as aquatic plant which has the ability to absorbpollutants from aquatic environments with rapid proliferation. Asattempts for controlling it has not been completely successful, thebest management strategy is to find some usage for them (Patel,2012). The most possible usage of water hyacinth includes mak-ing of animal fodder/fish feed (Aboud et al., 2005), biosorbent forthe removal of toxic metals (Malik, 2007), production of biogas andbioethanol (Mshandete et al., 2004), compost (Szczeck, 1999), pa-per manufacturing (De Groote et al., 2003), also as phytor-emediation agent (Sajn-Slak et al., 2005). In addition, Indianscientists have suggested many formulation of medicines usingwater hyacinth for treating diseases (Oudhia, 1999).

Moreover, after the removal of pollutants from waste water,water hyacinth can be used for recovering some of the toxic andnon-degradable materials like heavy metals (Isarankura-Na-Ayudhya et al., 2007). The abilities of water hyacinth such ashigher growth rate, pollutant absorption efficiency, low operationcost and renewability shows that using this plant it can beconsidered as a suitable technology for the treatment of waste-water. Malik (2007) reported that naturally water hyacinth createserious challenges in the filed of navigation, irrigation, and powergeneration. Therefore, inorder to avoid these problems using ofphytoremediation technology must be carried out along with thecontrolling of water hyacinth. Mahamadi (2011) found that some ofthe aquatic plants like water hyacinth can also be used for theproduction of biofuels. This technology to produce biofuels canovercome both environmental pollution and the depletion of en-ergy sources worldwide. Rezania et al. (2015) have reported thatdried water hyacinth can used for manufacturing briquette, whichis used for co-firing in coal power plant.

The main reason for releasing huge amount of wastewater intothe environment is because of increase in population, urbanizationand industrialization, which mainly constitutes organic mattersand heavy metals (Lalevic et al., 2012). That is why a reliabletechnology is needed to treat wastewater before it is being releasedinto the water bodies (Talaie et al., 2011a). Although, wastewatertreatment technologies are often costly, they are not always envi-ronmental friendly (Dixit et al., 2011; Talaie et al., 2011b). Therefore,environmental friendly technologies have been gaining attentionamong the researchers worldwide. Many researchers have reportedthe application of phytoremediation techniques for treatingdifferent types of wastewater. Water hyacinth, water lettuce andvetiver grass are plants that have been used for the removal of widerange of pollutants, which includes biochemical oxygen demand,heavy metals, total suspended solids, chemical oxygen demand,dissolved solids, nitrogen and phosphorous removal (Gupta et al.,2012). The different applications of water hyacinth have beenillustrated in (Fig. 1).

Recently, only few review papers related to wastewater treat-ment using water hyacinth have been published (Mahamadi, 2011;Patel, 2012; Gupta et al., 2012; Rezania et al., 2015). Mostly thisreview emphasize the most recent studies during the past five

years for the uptake and removal of organic, inorganic and heavymetal present in waster water using water hyacinth to make it as asuitable, inexpensive, effective and environmental friendly tech-nology for treating wastewater. The main focus of this review is tocompare how water hyacinth is effective in the removal of pollut-ants fromwastewater in comparision to other aquatic plants and toprovide insight for the development and new emerging technolo-gies of phytoremediation.

2. Water hyacinth

For many centuries water hyacinth has been applied as anornamental crop due to its attractive appearance by humans.Waterhyacinth was also introduced as the invasive and free-floatingaquatic macrophyte bymany botanists (Gopal,1987). It is amemberof the family Pontederiaceae which is indigenous to Brazil, theAmazon basin and Ecuador region (Tellez et al., 2008). The growthof this plant on the surface of water can reduce the penetration ofsunlight into the water. Sunlight is vital for many photosyntheticorganisms, reducing sunlight means reducing the grow rate ofphotosynthetic organisms and at the same time disturbing theecological balance (Tiwari et al., 2007). More studies are foundrelated to water hyacinth in the tropical and subtropical regionsbecause of its abundance in these regions. The ecology, livingconditions and the applications of water hyacinth is described by(Klumpp et al., 2002). Water hyacinth has long roots which aregenerally suspended in water. The root structure of aquatic plantsin particular water hyacinth can present suitable environment forthe aerobic microorganisms to function in the sewage system.Aerobic microorganisms use the organic matter and nutrient pre-sent in the wastewater and convert them into inorganic com-pounds, which can be utilized by the plants (Gopal, 1987).

This plant is reported to be as one of the most productive plantsworldwide (Gopal, 1987). Usually, the growth of water hyacinthgrowth is rapid due to the absence of natural enemies or compet-itor in non-indigenous countries, where water hyacinth has beenrecently transferred (Malik, 2007). Usually, two million water hy-acinths exist per each hectare of water, which is approximatelyequal of 270e400 tons (Kunatsa et al., 2013). Water hyacinth isfrequently mentioned in literature as one of the most problematicplants in theworld due to its uncontrollable growth inwater bodiessuch as irrigation systems or open ponds. Water hyacinth canrapidly grow over 60 kg per each m2 of water surface by which itcan cause critical effects on sustainable development of economy(Ganguly et al., 2012).

2.1. Morphology and habitat

The mature water hyacinth comprises of stolon's, leaves, fruitclusters, long pendant roots, leaves and rhizome. The averageheight of water hyacinth is 40 cm. However, sometimes it can growup to 1 m height. Water hyacinth has 6 to 10 lily-like flowers,diameter of each one is 4e7 cm. Different parts of water hyacinthsuch as the stems and leaves are made from air-filled tissues whichallows the plant to float on water (Fig. 2).

Fig. 1. Different applications of water hyacinth.

S. Rezania et al. / Journal of Environmental Management 163 (2015) 125e133 127

Water hyacinth has the ability to tolerate drought condition andcan survive in the moist sediments for months (Center et al., 2002).Four our species of water hyacinth including E. azurea, E. crassipes, E.diversifolia and E. paniculata have been discovered so far (Vermaet al., 2003). Among these it is found that E. crassipes has widelyinvaded to Europe, Africa, Asia and North America (Fig. 3) (Shanabet al., 2010). Lake Victoria, located in Africa is one of the largestlakes in the word that is being covered with thick layer of waterhyacinth (Kateregga and Sterner, 2007). The other countries to bethreatened by this weed include Spain and Portugal (DellaGrecaet al., 2009), along with the Sundarbans mangrove forest ofBangladesh (Biswas et al., 2007).

Over growth of this plant in India has caused severe siltation inthe wetlands of the Kaziranga National Park and Deepor Beel lake.Jimeonez and Balandra (2007) reported that nearly 40,000 ha ofwater bodies are threatened by this notorious weed in Mexico.According to Chu et al. (2006) in China, invasion of water hyacinthhas become a serious environmental issue. Several ecological im-pacts in SacramentoeSan Joaquin River Delta located in Californiahas been reported by Khanna et al. (2011). One of the problems toeradicate water hyacinth is because of its seed, which is known tosurvive up to 20 years (Patel, 2012). Although, sufficient researchand efforts have been made to eradicate water hyacinth, thisnotorious weed continues to propagate worldwide successfully.Current geographical distribution of water hyacinth in the world isshown in (Fig. 3).

Nutrient enriched waters are most favorable for the growth ofwater hyacinth and at the same time it can also tolerate low con-centration of nutrients. The growth of water hyacinth in seawater islimited because of salinity, that is the main reason why this plantcannot be found in the coastal areas (Jafari, 2010). The growthconditions of water hyacinth are summarized in Table 1.

3. Application of aquatic plants in wastewater treatment forthe removal of pollutants

Wastewater is a mixture of pure water with large number ofchemicals (including organic and inorganic) and heavy metalswhich can be produced from domestic, industrial and commercialactivities, in addition to storm water, surface water and groundwater (Dixit et al., 2011). Due to the danger of the entry of chemicalsinto wastewater it must be treated before the final disposal. Manyphysical, chemical and biological methods have been developed forthe treatment of wastewater. It is reported that biological methodsare more interesting for wastewater treatment and one of thebranches of biological method for wastewater treatment is phy-toremediation (Roongtanakiat et al., 2007). The concept of thismethod is based on the using of plants and microorganisms in thesame process as to remove the pollutants from environment (Lu,2009). Among phytoremediation techniques, artificial wetlands(AW) is known to be as the most effective technology to treatwastewater. The AWs can promote biodiversity via preparation of a

Fig. 2. Different parts of water hyacinth (Eichhornia crassipes). a) Leaves b) Baby plant c) Rhizome d) Flower.

Fig. 3. Current geographical distribution of water hyacinth in the world.

S. Rezania et al. / Journal of Environmental Management 163 (2015) 125e133128

large habitat for a wide number of wildlife such as the reptiles,rodents, fishes and birds (Dixon et al., 2003). AWs also helps toimprove air quality and prevention of climate changes by lesserproduction of carbon dioxide, hydrological functions and bio-methylation (Azaizeh et al., 2003). Generally, AWs are described tobe as environment friendly, simple, economic, effective andecologically sound technology (Roongtanakiat et al., 2007) whichrequire lesser land space (Lu, 2009).

It should be noted that the selection of suitable species of plantsis important for the implementation of phytoremediation (DeStefani et al., 2011). The selected species must contain thefollowing features: (1) high ability to uptake both organic andinorganic pollutants; (2) high ability to grow faster in wastewater;and (3) should be easy to control (Roongtanakiat et al., 2007). Itshould be also noted that the ability of pollutant removal variesfrom species to species, plant to plant within a genus (Singh et al.,

Table 1Water hyacinth growth conditions.

Factors Range References

Growth rate on the basis of dry weight 0.04e0.08 kg dry weight/m2/day Gopal, 1987Growth rate on the basis of surface 1.012e1.077 m2/day Gopal, 1987Growth rate on the basis of plan number 1610 plants can be produced from only 10 plants during 10 months Sooknah and Wilkie, 2004Water pH 6e8 �C Gopal, 1987Water salinity Less than 5 mg/L De Casabianca et al., 1995Water temperature 10e40 �C (optimum temperature 25e27.5 �C) Wilson et al., 2000

S. Rezania et al. / Journal of Environmental Management 163 (2015) 125e133 129

2003). The rate of photosynthetic activity and plant growth have akey role during the implementation of phytoremediation technol-ogy for the removal of low to moderate amount of pollutants (Xiaand Ma, 2006; Jamuna et al., 2009). In addition to water hyacinth,plants like Water Lettuce (Pistia stratiotes), Duckweed (Waterlemna), Bulrush (Typha), Vetiver Grass (Chrysopogon zizanioides),Common Reed (Phragmites australis) have been successfullyimplemented for the treatment of wastewater containing differenttypes of pollutant (Lu et al., 2010; Dipu et al., 2011; Girija et al.,2011).

Water hyacinth, the most exceedingly problematic aquatic weedwas discovered to be exceptionally difficult to control and eradicatethe plant from the water bodies, however its ability to uptakenutreint supplements has given a conceivable route for its use inphytoremediation. In the most recent years the exploration ofwater hyacinth as the bioindicator for heavy metal removal presentin the aquatic ecosystems have been demonstrated (Priya andSelvan, 2014). More research is expected to accomplish a moreprominent productivity in the removal of contaminants or differenttreatment strategies of the plant and its parts which can be focusedin near future. According to (Koutika and Rainey, 2015) apart fromthe impacts shown by Salvinia molesta and E. crassipes towards theenvironment and human health, water hyacinth has more advan-tageous impacts in terms of phytoremediation capacity, biogasgeneration, production of animal feed and compost.

3.1. Removal of heavy metals using water hyacinth

Nowadays, human health is being threatened with the releaseof polluted wastewater in presence of heavy metals into theenvironment. Lasat (2002) has shown that plants are successful inremoving the heavy metals. The use of plants as biosorbents forthe removal of heavy metals is considered to be inexpensive,effective and eco-friendly technology. Phytoremediation can beconsidered advantageous if the plant is considered to be as solar-driven pump which can concentrate and extract particular type ofelements present in the polluted wastewater (Tripathy andUpadhyay, 2003). The root of the plant helps to absorb the pol-lutants existing in the wastewater, particularly the heavy metalsand will help in improving the quality of water (Sooknah andWilkie, 2004).

Four aquatic plants namely water hyacinth (Eichornia crassipes),water lettuce (P. stratiotes), zebra surge (Scirpus tabernaemontani)and taro (Colocasia esculenta) were evaluated for their effectivenessin the removal of mercury fromwastewater. It was found that for allthe plants, root seemed to play a major role for the uptake ofmercury from wastewater (Skinner et al., 2007). According to Parket al. (2019) biosorbents used for the removal of metal ions fromwastewater can be divided into seven categories: (1) bacteria, (2)fungi, (3) algae, (4) industrial wastes, (5) agricultural wastes, (6)natural residues and (7) other biomaterials. Suzuki et al. (2005)have reported the use of seaweeds as the most inexpensive andaccessible material that has gained a lot of attention as biosorbent.Klumpp et al. (2002) demonstrated that aquatic macrophytes with

higher growth rate such as water hyacinth can be potentiallyapplied to remove heavy metals from wastewater. This plantrecently gained attention as a possible absorbent for the treatmentof wastewater polluted with heavy metals (Mahamadi andNharingo, 2007, 2010a, 2010b). Aquatic macrophytes have greaterpotential to accumulate heavy metals present inside their plantbodies where, (Priya and Selvan, 2014) have mentioned water hy-acinth to be as a huge potential for the removal of wide range ofpollutants from wastewater.

Liao and Cheng (2004) ranked the heavy metal removal ratebased on the ability of water hyacinth to remove(Cu > Zn>Ni > Pb > Cd) and showed that higher and lower removalefficiency belonged to Cu and Cd, respectively. Xiaomei et al. (2004)used water hyacinth for the removal of Zn and Cd fromwastewaterand also measured the concentration of Cd and Zn absorbed indifferent parts of water hyacinth (stem, leaves, roots, flowers). Itwas observed for the presence of 2040mg/kg of Cd and 9650mg/kgof Zn accumulated in the roots of water hyacinth. According toShaban et al. (2005) to treat one liter of wastewater contaminatedwith 1500 mg/L arsenic requires 30 g of dried water hyacinth rootfor a period of 24 h Emerhi (2011) estimated chromium (III)removal from the aqueous solution and found the removal rate tobe 87.52% with 10 mg Cr/1 solution. Gupta and Balomajumder(2015) found that water hyacinth can uptake more than 99% ofphenol in a single and twofold solution of Cr and Phenol (at 10 mg/L), in 14 and 11 days individually. Padmapriya and Murugesan(2012), during their study for the removal of heavy metals inaqueous solution using water hyacinth found Langmuir andFreundlich models fitted well for the biosorption of all the metalions.

Jadia and Fulekar (2009) reported that heavymetals are uptakenby the roots of the plant, translocated to the shoots and other planttissues, where they are concentrated and harvesting the plant canpermanently remove these contaminants. Moreover valuableheavy metals can be recovered from the plants by burning andextracting the metals from the ash. The most recent studies beingcarried out for the removal of heavy metals using water hyacinth islisted in Table 2.

3.2. Removal of inorganic and organic compound

Water hyacinth has been widely studied in the laboratory atpilot and large scale for the removal of organic matter present inthe waster water in comparison to other aquatic plants (Costa et al.,2000). Althoughwater hyacinth is known to be a persistent plant allover the world, it is being widely used as a main resource for wastemanagement and agricultural process (Malik, 2007). Both the fieldand laboratory studies have shown that water hyacinth is capable ofremoving large number of pollutants present in the swine waste-water (Valero et al., 2007). Duckweed and water hyacinth is beingconsidered for the treatment of dairy and pig manure basedwastewater (Sooknah andWilkie, 2004). The treated wastewater inthe presence of water hyacinth for the duration of 25 days resultedin the reduction (37, 47, 54 and 33%) of solids, calcium, magnesium

Table 2Recent studies on the removal of heavy metals using water hyacinth.

Type of waste water Uptake of heavy metals Findings/Highlights References

Wastewater from simulated wetland (Cr), (Cu) Almost 65% removal of heavy metals was achieved usingwater hyacinth.

Lissy et al., 2011

Synthetic waste water (Cu) Concentration of Cu decreased as mentioned below:5.5e2.1 mg/L¼ (61.6% removal)2.5 to 0.11 mg/L¼ (95.6% removal)1.5 to 0.04 mg/L¼ (97.3% removal)

Mokhtar et al., 2011

Agricultural drain, river and mixedindustrial drain.

(Zn), (Cu), (Ni) The order of trace metal accumulation in the root tissue wasfound to be as Zn > Cu > Ni. The bio concentration factor forCu, Ni and Zn present in the water hyacinth root was foundto be 1344.6, 1250.0, 22,758.6 respectively.

Hammad, 2011

Simulated radio contaminatedaqueous solution

(Cs) (Co) Higher removal rate of60Co (100%) in presence of60Co inwaste solution obtained, where highest 137 Cs uptake valuefrom the waste solution, near to 80% was observed with theexposure to sunlight along with the presence of60Co.

Saleh, 2012

Artificial lake water (Zn), (Cu), (Pb), (Cd) Initial concentration of Zn, Cu, Pb and Cd in water (500, 250,250 and 50 lg/L) was found to decreased in the order ofnPb> Cu> Cd > Zn during first day. After 8 days the removalefficiency was 8% and 24% (Cu), 11% and 26% (Pb), 24% and50% (Cd), 18% and 57% (Zn) at pH 8 and pH 6.

Smolyakov, 2012

Composting wastewater (Cd), (Zn), (Fe), (Mn),(Pb), (Ni), (Cr), (Cu)

Total metal concentration was found to increase during theprocess of composting. Water soluble Cd, Pb, Ni and DTPAextractable Pb and Cdwere not detected, but all of the metalconcentration was observed in the TCLP test duringcomposting.

Singh and Kalamdhad, 2013

Industrial wastewater (Zn), (Cu), (Cd) (Cr) Appreciable amount of heavy metal occurred during a 15day experiment. Maximum removal efficiency of metal wasrecorded during the 10th day and the leaves of waterhyacinth was found to be as least accumulator incomparison to the roots.

Yapoga et al., 2013

Diluting stock solution in drinkingwater

As (V), As (III) A prototype filter made from water hyacinth (20 g) wascapable of removing 80% and 84% of arsenic from drinkingwater with the concentration of 250 and 1000 mg/L.

Brima and Haris, 2014

Hydroponic medium (Hg) Accumulation of mercury ion was 1.99, 1.74 and 1.39 mg/gdry weight in the root, leaf, and petiole tissues.

Malar et al., 2015

Artificial waste water (Cd (NO3)2$4H2Oin deionized water)

(Cd) Use of biochar pyrolyzed from water hyacinth resulted inthe removal of nearly 100% Cd from the aqueous solutionwithin 1 h at initial Cd � 50 mg L�1.

Zhang et al., 2015

Artificial waste water (NiCl2_6H2O) wasadded to obtain concentrations of1, 2, 3 and 4 mg L�1

(Ni) Ni adsorption was found to be qucik during first 24 h.Higher Ni accumulation was observed in roots incomparision to aerial parts.

Gonzalez et al., 2015

S. Rezania et al. / Journal of Environmental Management 163 (2015) 125e133130

and total hardness. Wastewater from duck farm was treated bywater hyacinth and resulted in 64%, 23% and 21% removal of COD,TP and TN (Jianbo et al., 2008). In combination of water hyacinthand duckweed for treating dairy wastewater it could remove 79% oftotal nitrogen and 69% of total phosphorus (Tripathy and Upadhyay,2003). Chen et al. (2010) demonstrated that 36% of nitrogen andphosphorus could be removed from swine wastewater using waterhyacinth. Also reported among the different forms of nitrogen,ammonical nitrogen (NH3eN)was found to be removed to a greaterextend when compared to other forms of nitrogen.

Ismail et al. (2015) showed the efficiency of water hyacinth andwater lettuce for the uptake of nitrate, ortho-phosphate, nitrite andammoniacal nitrogen. It was found that water hyacinth exhibitedbetter performance for reducing nitrate in comparison to ortho-phosphate. Valipour et al. (2015) in their latest study showed thatthe roots of water hyacinth are primarily involved in the trans-portation, where the shoots resulted in the accumulation ofconsiderable amount of nutrients (N & P) in comparison to the rootarea. The recent studies for the removal of pollutants using waterhyacinth are summarized in Table 3.

4. Control of water hyacinth growth

Many studies have shown that mechanical, chemical and bio-logical methods can be applied to eradicate water hyacinth but allthese methods are only partially successful (Shabana andMohamed, 2005; Zhang et al., 2005). Biological control of

E. crassipes has been conducted in many parts of the world and theways of controlling the growth of water hyacinth has beenaddressed by several researchers (Koutika and Rainey, 2015). Waterhyacinth, theworst aquatic weedwas found to be nearly impossibleto eradicate from the water bodies, though its quest for nutrientshas given a possible way for its use in phytoremediation. Centeret al. (1999) showed that sustained herbivory of E. crassipesreduced proportionately the biomass and floral structures. A seriesnovel self-spreading phenoxy carboxylic acid derivatives weredesign and synthesized, which can float on the water surface andshowed excellent herbicidal activities against the water hyacinth(Zheng et al., 2015).

Improved and large scale utilization of the water hyacinth spe-cies can serve as a positive approach to control, especially in thedeveloping countries. The controlling mechanisms have had animportant impact in controlling the spread of E. crassipes (Güere~naet al., 2015). Malik (2007), showed a remarkable approach towardsthe controlling and eradication of water hyacinth growth alongwith the combination of herbicidal control, integrated biologicalcontrol and watershed management controlling nutrient supply.In-spite of these approaches still there is an extensive instability intheir monetary due to the aspects of underdeveloped extractionand handling innovations. Overall, when considering the social andenvironmental benefits, the frameworks can possibly providedbetter socio-economic returns (Güere~na et al., 2015). Therefore, iferadication of this notorious weed is not possible so easily, then thefeasibility of using this plant as a energy resource (bioethanol,

Table 3Recent studies for the removal of organic and inorganic using water hyacinth.

Type of waste water Removal of organic and inorganic Findings/Highlights References

Dye wastewater Nitrogen, ammonium nitrogen, (BOD),pH, hardness, (TDS), (DO), conductivity,(COD), nitrate

The experiment was carried using 25%, 50%, 75% and 100%of waste water. A significant decrease in all of theparameters was noticed. Water hyacinth showed betterefficiency with 25%e50% of waste water.

Shah et al., 2010

Eutrophic lake Transparency, (TN), (NH4), (NO3), (TP),(PO4), (COD)

Water quality improved surrounding the water hyacinthmats, also in most of the parameters the concentration wasfound to be decreased.

Wang et al., 2012

Metallurgical, textile andpharmaceutical wastewater

(BOD), (DO), nitrate Average for (BOD) ¼ 54.80%, asmetallurgical > textile > pharmaceutical wastewater(DO) ¼ 62.64% as metallurgical > pharmaceutical > textilewastewaterNitrate-nitrogen ¼ 48.57% astextile > metallurgical > pharmaceutical wastewater.

Ajayi and Ogunbayio, 2012

Domestic waste water (COD), (TN), (TP) 80% of (COD), 75% of (TN) and 75% of (TP) reductionhappened during the first week of experiment. It was foundthat 20% or 15 L of water reduction occurred weekly and40% increase in the plant biomass was observed after 14days.

Rezania et al., 2013

Polluted river water (TDS), total hardness, sulfate, phosphate,(EC), pH, (NO2), (NO3), (TN)

Significant reduction of electrical conductivity (25%decrease), total dissolved solids (TDS) (26%), sulphate (45%),phosphate (33%) and total hardness (37%) between thesample points SR1 and SR3 were obtained.

Moyo et al., 2013

Municipal waste water (BOD), (COD), (NO3�eN) (TKN), (PO3�4 eP) Removal of parameters for mixed culture of Eichhornia

crassipes and Salvinia natans: 84.5% of (BOD) 83.2% of (COD)26.6% of (NO3�eN) 53.0% of (TKN)56.6% of (PO3�

4 eP).

Kumari and Tripathi, 2014

Domestic waste water pH, (COD), (PO43), (NO3), (NH3), (TOC),

biomass growth rateOptimum removal rate for all the parameters was found tobe between 12 and 15 days using WH.Optimum growth rate was found in 18 days with removalrate of (COD) 95%, TOC 45%, (PO4

3) 45%, (NH3) 85%.

Rezania et al., 2014

Domestic waste water (TSS), (COD), (NHþ4 ), (PO

�34 ) Comparison of Water hyacinth and Water morning glory

showed: 37.8%e53.3% for TSS; 44.4%e53.4% for COD; 56.7%e61.4% for PO�3

4 - and 26.8%e32.6% for NH4þ. Lower valuesbelong to Water morning glory and higher values belong towater hyacinth.

Loan et al., 2014

Domestic sewage water Ammonia, Nitrate, phosphate Water hyacinthþ papaya stem resulted in the removal rate:(67%) reduction in ammonia, (74%) nitrate removal and(71%) phosphate

Anandha Varun andKalpana, 2015

Domestic waste water (COD), (BOD), (TN), (TP), (TSS), (PO4eP),(NH3eN)

COD reduction: (79%), BOD removal: (86%), TN: (76.61%),TP: (44.84%), TSS: (73.02%), PO4eP: (38.69%), NH3eN:(72.48%) at HRT of 14 h was achieved.

Valipour et al., 2015

S. Rezania et al. / Journal of Environmental Management 163 (2015) 125e133 131

biogas, briquette) should be aimed by the researchers.

5. Future perspectives of phytotechnology/phytoremediationin pollution control

Phytoremediation is a moderately late innovation and is seen aspractical, proficient, novel, eco-friendly technology, still in its initialimprovement stages and full scale applications are still constrained.Numerous plants like Eichhornia crassipes have been reported to beas a particulate contamination phytoremediator (Rai and Panda,2014). In this manner, the usage of intrusive plants in pollutantreduction phytotechnologies may help with their practical appli-cation (Rai, 2015). Also, the utilization of water hyacinth in waste-water treatment frameworks has been progressively reported andtreatment regimens are created as a consequence of the lasteddevelopment in relation to the approach towards phytor-emediation (Priya and Selvan, 2014). The presence of arsenic indrinking water is a noteworthy wellbeing concern in numerousnations worldwide with a huge number of individuals already be-ing affected. Although various aquatic plants have been indicatedfor the arsenic uptake and recommended for arsenic phytor-emediation, the administration, transfer and disposal of thesephytoremediating aquatic macrophytes is a noteworthy concerntowards the effective usage of phytoremediation innovation asthere is an urgent requirement for creating cheaper systems taking

into account the accessible materials, for the removal of Arsenicfrom drinking water (Raju et al., 2015).

Meanwhile it is imperative that clear vision about this innova-tion needs to be considered and the precise data obtained should bemade accessible to all the public as to improve its adequacy as aworldwide manageable innovative technology. In addition, phy-toremediation has been considered to be an eco-friendly “green”and low-tech distinct option for more dynamic and remedialtechniques (Jadia and Fulekar, 2009). As described by Ali et al.(2013) this innovative technology additionally needs lower en-ergy resources, moreover its a natural one and does not requirepower or other kind of vitality. Disregarding the numerous diffi-culties, phytoremediation is seen as a green remediation technol-ogy with a greater potential. The execution of more research andinnovation is needed for this technology to advance and promote inthe developing countries due to its lower cost and feasibility.

6. conclusion

This paper has shown the different possibilities of using waterhyacinth for the removal of pollutants present in waste water.Water hyacinth is found to be suitable for controlling the urban anddifferent types of waste water coming from the industry. It is alsodemonstrated that among the aquatic plants, water hyacinth is adecent and viable possibility for nutrient uptake and improving the

S. Rezania et al. / Journal of Environmental Management 163 (2015) 125e133132

water quality. Water hyacinth can cause economic, environmentaldisaster and is difficult to control. However, with the innovative useof phtotechnology, it can be a viable tool for numerous purposeslike power generation, food security and for the environmentalremediation The comparison of the current phytotechnologyframeworks and phyto-remediation utilizing water hyacinth, it canbe recommended that utilizing water hyacinth as a part of wastewater treatment systems has more noteworthy and exceptionaleffect on the environment by up-taking CO2 from the atmosphere,at the same time gathering supplement for the plant. Likewise as interms of expense, it is less expensive than different advancedtechnologies which needs more cost to work for the evacuation ofpollutants from the wastewater. This methodology will positivelyhelp for going towards the advancement of a few new phyto-technologies for usingwater hyacinth to treat wastewater in future.

Acknowledgment

The authors would like to acknowledge the support receivedfrom the JSPS Asian core program (ACP) governance group, FlagshipGrant (Q.Ji30000.2517.10H25), GUP Grant (Q.ji30000.2409.02G41),COE Flagship Grant (Q.J130000.2422.02G75) received support fromthe Universiti Teknologi Malaysia. The authors also would like tothank Prof. Kenzo Iwao, National Institute of Technology (NIT),Japan for his valuable comments to improve the manuscript.

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