Phytoremediation Of Lindane Using Water Hyacinth

Getting Started In Hydroponics

Hydroponics Home System

Get Instant Access

Figure 5. Time course experiment of lindane disappearance in solution with chilli and coriander. Controls (white columns), chilli (black columns), coriander (grey columns). Data points represent the means of 5 replicates determinations. Bar = SD.

the effect of the rhizosphere on these compounds. Five plant species were harvested and separated into roots, stems and leaves: Chenopodium vulgare, Solanum nigrum, Cytisus striatus, Vicia sativa and Avena sativa. Concentrations of total HCH in plant organs ranged between 1.7 and 62.5 mg kg-1, depending on plant species and organs. Leaves systematically contained the highest amount of HCH, probably due to the volatilization of HCH isomers from the soil surface and subsequent sorption by leaves. In one species, C. striatus, the metabolites pentachlorocyclohexene, cyclopentiltrichloroethene and 6 trichloro, 4-en-hexanoic derivates were also detected in the all plant tissues analysed [71]. Data obtained from the bulk and rhizosphere soils from C. striatus and A. sativa suggest that both plant species tend to reduce the levels of all HCH isomers in the rhizosphere. This could be due to the enhanced biodegradation in the rhizosphere, root exudation of enzymes able to dechlorinate HCH isomers and/or sequestration by partitioning into the lipophilic plant tissues or uptake by the roots.

In the case of HCH, phytoremediation has thus shown its own limitations, even in the favourable case of hydroponic systems, where the pollutant is made highly bioavailable. Since rhizosphere microbial activity is known to aid the release of bound pesticide residues in soil, which can in turn enhance uptake and transformation, by plants, a combination of bioremediation and phytoremediation, or the phytostimulation of rhizosphere microorganisms, is likely to be more successful.

Phytostimulation of bacteria present or added in soil seems the most promising approach to remove lindane from contaminated sites. It has long been known that plants release a vast range of organic materials through roots into the rhizosphere. These exudates contain water soluble, insoluble and volatile compounds including sugars, amino acids, organic acids, flavonones, phenolic compounds and even enzymes [12, 7377]. The root exudates can enhance the acquisition of nutrients by plants; stimulate microbial growth in the rhizosphere; and change pH, water flux and availability of oxygen. Microorganisms able to use phenolic compounds as a carbon source often have enzymes that can co-metabolise pollutants with similar structures. Plants have also a great capacity to release secondary metabolites having a surfactant activity, which is favourable for phytoremediation purposes. Thus the degradation of several chlorinated pesticides has been reported to be higher in a vegetated soil than a non-vegetated soil. For example, the biodegradation of HCH isomers is enhanced in rhizosphere soils of Kochia sp., as compared to bulk soil, even if the mechanism by which this occurs is not yet known [78].

A dynamic synergy does exist between plant roots and soil microorganisms. The microbial activity in the immediate vicinity of the root (rhizosphere) seems to offer a favourable environment for co-metabolism of soil-bound and recalcitrant chemicals. The microbial transformations of organic compounds are not always driven by energy needs, but also by the necessity to reduce toxicity for which microbes may have to suffer an energy deficit. Thus, the processes may be helped and driven by the abundant energy provided by root exudates. Certain soil microorganisms can also produce biosurfactant compounds that may facilitate the removal and degradation of organic chemicals by increasing their availability to plants. Plants can thus take advantage of an increased bioavailability of nutrients and degradation of phytotoxic soil contaminants.

A successful example of exploring rhizosphere microorganisms for the decontamination of pesticide-contaminated soils has been highlighted by the recent findings of a coordinated Indo-Swiss project [77]. The project was aimed at investigating possibilities to remediate agricultural soils contaminated with lindane, using a plant-rhizosphere system. Mineralisation of 14C lindane by rhizospheric soils of plants growing in lindane-contaminated fields indicated that microorganisms capable of degrading the insecticide were present. Enrichment culture techniques resulted in the isolation of bacteria growing in the presence of lindane. Klebsiella sp., Pseudomonas sp., and Pseudoarthrobacter sp. degraded up to 50% of lindane with the formation of 2,3,4-trichlorobenzene. Root exudates of some plants stimulated the growth of lindane degrading bacterium Pseudomonas sp., indicating the need for an approach, which includes both plants and interacting microorganisms for an efficient degradation of pesticides. To treat lindane-contaminated soils, it thus appears that phytostimulation would be the most appropriate technique.

Soil composition influences sorption, soil pH, bulk density and water retention, all of which affecting aeration, nutrient availability and thus bioavailability and biodegradability of contaminants [61]. A high density of indigenous S. paucimobilis was found in the plant debris fraction of soil and it was postulated that plant organic matter integrated into the soil aggregates served as a microhabitat rich in growth substrates. This can be the basis for the application of plant-derived organic amendments to soil as a phytostimulation strategy, like rice straw or other cellulosic material, because of their efficiency, availability in large quantities and low cost [52]. For example, the Daramend® technology for bioremediation of HCH-contaminated soils is based on the application of solid plant-derived organic matter providing nutrients and a non-toxic habitat for indigenous microorganisms; it creates a concentration gradient that facilitates diffusion of organic contaminants from pockets of higher to lower concentrations on the amendment surface, where they are more bioavailable [79]. Since the texture, nutrient requirements and microbial populations of each soil are specific, the usefulness and composition of amendments should be assessed on a case-by-case basis.

Detailed strategies for optimising treatments on sites contaminated with HCHs remain to be established and could involve enhanced natural attenuation and optimisation of environmental conditions, to stimulate growth and biodegradation by indigenous microorganisms. Supplemental nutrients and/or organic amendments could be added to enrich the soil and stimulate the bacteria degrading HCH. Bioaugmentation with phytostimulation or a vegetative cover should also be tested, either by increasing the population of microorganisms able to degrade HCH isomers, or by increasing the bioavailability of the insecticide.

4. Conclusions and perspectives

Both examples developed here show that plants and soil microorganisms have certain limitations with respect to their individual abilities to remove and degrade organic pollutants like pesticides, and other molecules containing chlorines and/or aromatic ring structures. However, plants and bacteria have very specific and complementary metabolic pathways, and their combined appropriate use can breakdown many man-made chemicals. Therefore, a synergy between rhizospheric microorganisms leading to increased availability of hydrophobic compounds and plants leading to their removal and/or degradation, may overcome many of the limitations, thus providing a sound basis for enhancing biological remediation of contaminated environments.

Phytostimulation or rhizoremediation is of particular importance because it refers to an important contribution that microorganisms in the root-zone (rhizosphere) make to the overall breakdown and removal of organic pollutants by plants. Plant-microbial interactions in the rhizosphere are thus of utmost importance for the degradation of recalcitrant chemicals in the environment [12, 30, 80].

However, further research into the mechanisms by which plants can stimulate biodegradation and the complexity of the soil-plant-microbe system due to its interwoven nature is thus required to better explore and exploit their huge potential. Such studies must be done not only at laboratory scale, but also under real conditions, as demonstration projects, to optimise the phytoremediation process and convince regulators and the general public of the technique's feasibility [81, 82]. To increase its acceptance as a remediation concept, phytoremediation must also become an economically interesting approach and biomass disposal or use after the treatment is thus an important issue to consider. For example, the biomass of fibres, oil or fragrance producing plants like vetiver, could be used to recover these added-value products, if however their level of contamination is nil or low enough. Alternatively, contaminated biomass could be used for renewable energy generation, either by direct combustion, gasification or pyrolysis, or indirectly via biogas or biofuel production [83, 84].


[1] Courdouan, A; Marcacci, S; Gupta, S and Schwitzguebel, JP (2004) Lindane and technical HCH residues in Indian soils and sediments - A critical appraisal. Journal of Soils and Sediments 4: 192-196

[2] Pimental, D and Levitan, L (1986) Pesticides: amounts applied and amounts reaching pests. Bioscience

[3] Chaudhry, Q; Schröder, P; Werck-Reichhart, D; Grajek, W and Marecik, R (2002) Prospects and limitations of phytoremediation for the removal of persistent pesticides in the environment. Environmental Science and Pollution Research 9: 4-17

[4] Alexander, M (2000) Aging, bioavailability and overestimation of risk from environmental pollutants. Environmental Science and Technology 34: 4259-4265

[5] Anhalt, JC; Arthur, EL; Anderson, TA and Coats JR (2000) Degradation of atrazine, metolachlor and pendimethalin in pesticides-contaminated soils: Effects of aged residues on soil respiration and plant survival. Journal of Environmental Science and Health B 35: 417-438

[6] Hatzinger, PB and Alexander, M (1995) Effect of aging chemicals in soil on their biodegradability and extractability. Environmental Science and Technology 29: 537-545

[7] Dua, M; Singh, A; Sethunathan, N and Johri, AK (2002) Biotechnology and bioremediation: successes and limitations. Applied Microbiology and Biotechnology 59: 143-152

[8] Atterby, H; Smith, N; Chaudhry, Q and Stead, D (2002) Exploiting microbes and plants to clean up pesticide contaminated environments. Pesticide Outlook 13: 9-13

[9] Davis, LC; Castro-Diaz, S; Zhang, QZ and Erickson, LE (2002) Benefits of vegetation for soils with organic contaminants. Critical Reviews in Plant Sciences 21: 457-491

[10] Belden, JB; Clark, BW; Phillips, TA; Henderson, KL; Arthur, EL and Coats, JR (2004) Detoxification of pesticides residues in soil using phytoremediation. Pesticide Decontamination and Detoxification ACS Symposium Series 863: 155-167

[11] Karthikeyan, R; Davis, LC; Erickson, LE; Al-Khatib, K; Kulakow, PA; Barnes, PL: Hutchinson, SL and Nurzhanova, AA (2004) Potential for plant-based remediation of pesticides-contaminated soil and water using nontarget plants such as trees, shrubs and grasses. Critical Reviews in Plant Sciences 23: 91-101

[12] Kuiper, I; Lagendijk, EL; Bloemberg, GV and Lugtenberg, BJJ (2004) Rhizoremediation: a beneficial plant-microbe interaction. Molecular Plant-Microbe Interactions 17: 6-15

[13] Radosevich, M; Traina, SJ; Hao, YL and Tuovinen, OH (1994) Degradation and mineralization of atrazine by a soil bacterial isolate. Applied and Environmental Microbiology 61: 297-302

[14] Jin, R and Ke, J (2002) Impact of atrazine disposal on the water resources of the Yang river in Zhangjiakou area in China. Bulletin of Environmental Contamination and Toxicology 68: 893-900

[15] Vighi, M and Funari, E (1995) Pesticide Risk in Groundwater. Lewis Publishers, Boca Raton, FL, USA, ISBN 0-87371-439-3, 275 p

[16] Coleman, JOD; Frova, C; Schröder, P and Tissut, M (2002) Exploiting plant metabolism for the phytoremediation of persistent herbicides. Environmental Science and Pollution Research 9: 18-28

[17] Mersie, W and Seybold, C (1996) Adsorption and desorption of atrazine, deethylatrazine, deisopropylatrazine and hydroxyatrazine on levy wetland soil. Journal of Agricultural and Food Chemistry 44: 1925-1929

[18] Qiao, X; Ma, L and Hummel, HE (1996) Persistence of atrazine and occurrence of its primary metabolites in three soils. Journal of Agricultural and Food Chemistry 44: 2846-2848

[19] Shapir, N and Mandelbaum, RT (1997) Atrazine degradation in subsurface soil by indigenous and introduced microorganisms. Journal of Agricultural and Food Chemistry 45: 4481-4486

[20] Panshin, SY; Carter, DS and Bayless, RE (2000) Analysis of atrazine and four degradation products in the pore water of the vadose zone, Central Indiana. Environmental Science and Technology 34: 21312137

[21] Singh, BK; Kuhad, RC; Singh, A; Lal, R and Tripathi, KK (1999) Biochemical and molecular basis of pesticide degradation by microorganisms. Critical Reviews in Biotechnology 19: 197-225

[22] Piutti, S; Hallet, S; Rousseaux, S; Philippot, L; Soulas, G and Martin-Laurent, F (2002) Accelerated mineralisation of atrazine in maize rhizosphere soil. Biology and Fertility of Soils 36: 434-441

[23] Rhine, ED; Fuhrmann, JJ and Radosevich, M (2003) Microbial community responses to atrazine exposure and nutrient availability: linking degradation capacity to community structure. Microbial Ecology 46: 145-160

[24] Martin-Laurent, F; Cornet, L; Ranjard, L; Lopez-Gutierrez, JC; Philippot, L; Schwartz, C; Chaussod, R; Catroux, G and Soulas, G (2004) Estimation of atrazine-degrading genetic potential and activity in three French agricultural soils. FEMS Microbiology Ecology 48: 425-435

[25] Smith, D; Alvey, S and Crowley, DE (2005) Cooperative catabolic pathways within an atrazine-degrading enrichment culture isolated from soil. FEMS Microbiology Ecology 53: 265-273

[26] Burken, JG and Schnoor, JL (1996) Phytoremediation: plant uptake of atrazine and role of root exudates. Journal of Environmental Engineering 122: 958-963

[27] Burken, JG and Schnoor, JL (1997) Uptake and metabolism of atrazine by poplar trees. Environmental Science and Technology 31: 1399-1406

[28] Barfield, B; Blevins, R; Fogle, A; Madison, C; Inamdar, S; Carey, D and Evangelou, V (1998) Water quality impacts of natural filter strips. American Society of Agricultural Engineering 41: 371-381

[29] Singh, N; Megharaj, M; Kookana, RS; Naidu, R and Sethunathan, N (2004) Atrazine and simazine degradation in Pennisetum rhizosphere. Chemosphere 56: 257-263

[30] Van Eerd, LL; Hoagland, RE and Hall, JC (2003) Pesticide metabolism in plants and microorganisms. Weed Science 51: 472-495

[31] Wilson, PC; Whitwell, T and Klaine, SJ (2000) Metalaxyl and simazine toxicity to and uptake by Typha latifolia. Archives of Environmental Contamination and Toxicology 39: 282-288

[32] Marcacci, S and Schwitzguebel, JP (2005) Using plant phylogeny to predict detoxification of triazine herbicides, in Willey, N Ed., Phytoremediation: Methods and Reviews. Humana Press, NJ, USA, Chapter 20, (in press)

[33] Krutz, LJ; Senseman, A; Zablotowicz, RM and Matocha, MA (2005) Reducing herbicide runoff from agricultural fields with vegetative filter strips: a review. Weed Science 53: 353-367

[34] Nair, DR; Burken, JG; Licht, LA and Schnoor, JL (1993) Mineralization and uptake of triazine pesticides in soil-plant systems. Journal of Environmental Engineering 119: 842-854

[35] Anderson, KL; Wheeler, KA; Robinson, JB and Tuovinen, OH (2002) Atrazine mineralization potential in two wetlands. Water Research 36: 4785-4794

[36] Runes, HB; Jenkins, JJ; Moore, JA; Bottomley, PJ and Wilson, BD (2003) Treatment of atrazine in nursery irrigation runoff by a constructed wetland. Water Research 37: 539-550

[37] Anderson, TA and Coats, JR (1995) Screening rhizosphere soil samples for the ability to mineralize elevated concentrations of atrazine and metolachlor. Journal of Environmental Science and Health B 30: 473-484

[38] McKinlay, R and Kasperek, K (1998) Observations on decontamination of herbicide-polluted water by marsh plant systems. Water Research 33: 505-511

[39] Fernandez, TR; Whitwell, T; Riley, MB and Bernard, CR (1999) Evaluating semi-aquatic herbaceous perennials for use in herbicide phytoremediation. Journal of American Society of Horticultural Science 124: 539

[40] Bertea, CM and Camusso, W (2002) Vetiveria: anatomy, biochemistry and physiology, in Maffei, M Ed., Vetiveria. Taylor and Francis, London and New York, ISBN, 0-415-27586-5, pp. 19-43

[41] Truong, P (2002) Vetiver grass technology, in Maffei, M Ed., Vetiveria, Taylor and Francis, London and New York, ISBN, 0-415-27586-5, pp. 114-132.

[42] Briggs, GC; Bromilow, RH and Evans, AA (1982) Relationships between lipophilicity and root uptake and translocation of non-ionized chemicals by barley. Pesticide Science 13: 495-504

[43] Marcacci, S (2004) A phytoremediation approach to remove pesticides (atrazine and lindane) from contaminated environment, PhD thesis Nr 2950, EPFL, Lausanne, Switzerland.

[44] Wilson, PC; Whitwell, T and Klaine, SJ (1999) Phytotoxicity, uptake and distribution of 14C-simazine in Canna hybrida "Yellow King Humbert". Environmental Toxicology and Chemistry 18: 1462-1468

[45] Raveton, M; Ravanel, P; Serre, AM; Nurit, F and Tissut, M (1997) Kinetics of uptake and metabolism of atrazine in model plant system. Pesticide Science 49: 157-163

[46] Marcacci, S; Raveton, M; Ravanel, P and Schwitzguebel, JP (2005) The possible role of hydroxylation in the detoxification of atrazine in mature vetiver (Chrysopogon zizanioides Nash) grown in hydroponics. Zeitschrift für Naturforschung 60c: 427-434

[47] Marcacci, S; Raveton, M; Ravanel, P and Schwitzguebel, JP (2006) Conjugation of atrazine in vetiver (Chrysopogon zizanioides Nash) grown in hydroponics. Environmental and Experimental Botany (in press)

[48] Walker, K; Vallero, DA and Lewis, RG (1999) Factors influencing the distribution of lindane and other hexachlorocyclohexanes in the environment. Environmental Science and Technology 33: 4373-4378

[49] Wania, F; Mackay, D; Li, YF; Bidleman, TF and Strand, A (1999) Global chemical fate of a-hexachlorocyclohexane. 1. Evaluation of a global distribution model. Environmental Toxicology and Chemistry 18: 1390-1399

[50] Willett, KL; Ulrich, EM and Hites, RA (1998) Differential toxicity and environmental fates of hexachlorocyclohexane isomers. Environmental Science and Technology 32: 2197-2207

[51] Deo, PG; Karanth, NG and Karanth, NGK (1994) Biodegradation of hexachlorocyclohexane isomers in soil and food environment. Critical Reviews in Microbiology 20: 57-78

[52] Phillips, TM; Seech, AG; Lee, H and Trevors, JT (2005) Biodegradation of hexachlorocyclohexane (HCH) by microorganisms. Biodegradation 16: 363-392

[53] Van Liere, H; Staps, S; Pijls, C., Zwiep, G., Lassche, R. and Langenhoff, A. (2003) Full scale case: successful in situ bioremediation of a HCH contaminated industrial site in Central Europe (The Netherlands). Proceedings of the 7th International HCH and Pesticides Forum, Kyiv, Ukraine, 5-7 June 2003, ISBN 966-8187-31-8, pp. 128-132

[54] Pesce, SF and Wunderlin, DA (2004) Biodegradation of lindane by a native bacterial consortium isolated from contaminated river sediment. International Biodeterioration and Biodegradation 54: 255-260

[55] Pal, R; Bala, S; Dadwahl, M; Kumar, M; Dhingra, G; Prekash, O; Prabagaran, SR; Shivaji, S; Cullum, J; Holliger, C and Lal, R (2005) The hexachlorocyclohexane-degrading bacterial strains Sphingomonas paucimobilis B90A, UT26 and Sp. having similar lin genes are three distinct species, Sphingobium indicum sp. nov.; Sphingobium japonicum sp. nov.; and Sphingobium francense sp. nov. and reclassification of Sphingomonas chungburkensis as Sphingobium chungbukense comb. nov. International Journal of Systematic and Evolutionary Microbiology (in press)

[56] Endo, R; Kamakura, M; Miyauchi, K; Fukuda, M; Ohtsubo, Y; Tsuda, M and Nagata, Y (2005) Identification and characterization of genes involved in the downstream degradation pathway of Y-hexachlorocyclohexane in Sphingomonas paucimobilis UT26. Journal of Bacteriology 187: 847-853

[57] Miyauchi, K; Lee, HS; Fukuda, M; Takagi, M and Nagata, Y (2002) Cloning and characterization of linR, involved in regulation of the downstream pathway for Y-hexachlorocyclohexane degradation in Sphingomonas paucimobilis UT26. Applied and Environmental Microbiology 68: 1803-1807

[58] Suar, M; van der Meer, JR; Lawlor, K; Holliger, C and Lal, R (2004) Dynamics of multiple lin gene expression in Sphingomonas paucimobilis B90A in response to different hexachlorocyclohexane isomers. Applied and Environmental Microbiology 70: 6650-6656

[59] Okeke, BC; Siddique, T; Arbestain, MC and Frankenberger, WT (2002) Biodegradation of Y-hexachlorocyclohexane (Lindane) and a-hexachlorocyclohexane in water and soil slurry by a Pandoraea species. Journal of Agricultural and Food Chemistry 50: 2548-2555

[60] Kuritz, T (1999) Cyanobacteria as agents for the control of pollution by pesticides and chlorinated organic compounds. Journal of Applied Microbiology 85: 1865-1925

[61] Agnihotri, NP and Barooah, AK (1994) Bound residues of pesticides in soil and plant - A review. Journal of Scientific and Industrial Research 53: 850-861

[62] Bromilow, RH and Chamberlain, K (1995) Principles governing uptake and transport of chemicals, in Trapp, S and McFarlane, JC Eds., Plant Contamination - Modeling and Simulation of Organic Chemical Processes. Lewis Publishers, Boca Raton, FL, USA, ISBN 1-56670-078-7, pp. 37-68

[63] Sicbaldi, F; Sacchi, GA; Trevisan, M and Del Re, AAM (1997) Root uptake and xylem translocation of pesticides from different chemical classes. Pesticide Science 50: 111-119

[64] Burken, JG (2003) Uptake and metabolism of organic compounds: green-liver model, in McCutcheon, SC and Schnoor, JL Eds., Phytoremediation: Transformation and Control of Contaminants. Wiley Interscience, Hoboken, NJ, USA, ISBN 0-471-39435-1, pp. 59-84

[65] Li, H; Sheng, G; Chiou, CT and Xu, O (2005) Relation of organic contaminant equilibrium sorption and kinetic uptake in plants. Environmental Science and Technology 39: 4864-4870

[66] Singh, G; Kathpal, T; Spencer, W and Dhankar, J (1991) Dissipation of some organochlorine insecticides in cropped and uncropped soil. Environmental Pollution 70: 219-239

[67] Barriada-Pereira, M; Concha-Grana, E; González-Castro, MJ; Muniategui-Lorenzo, S; López-Mahía, P; Prada-Rodríguez, D and Fernández-Fernández, E (2003) Microwave-assisted extraction versus Soxhlet extraction in the analysis of 21 organochlorine pesticides in plants. Journal of Chromatography A 1008: 115-122

[68] Marcacci, S; Paratte, S and Schwitzguébel, JP (2002) Phytoextraction of lindane by chilli and coriander in hydroponic system, in T Macek, M Mackova and K Demnerova, Eds, Proceedings of the 12th International Biodeterioration and Biodegradation Symposium, Prague, Czech Republic, CSBMB Prague, JPM Tisk, p. 193, ISBN 80-86313-08-5

[69] Campanella, B and Paul, R (2000) Presence, in the rhizosphere and leaf extracts of zucchini (Cucurbita pepo L.) and melon (Cucumis melo L.), of molecules capable of increasing the apparent aqueous solubility of hydrophobic pollutants. International Journal of Phytoremediation 2: 145-158

[70] Li, H; Sheng, G; Sheng, W and Xu, O (2002) Uptake of trifluralin and lindane from water by ryegrass. Chemosphere 48: 335-341

[71] Barriada-Pereira, M; González-Castro, MJ; Muniategui-Lorenzo, S; López-Mahía, P; Prada-Rodríguez, D and Fernández-Fernández, E (2005) Organochlorine pesticides accumulation and degradation products in vegetation samples of a contaminated area in Galicia (NW Spain). Chemosphere 58: 15711578

[72] Monterroso, MC; Camps Arbestain, M; Calvelo Pereira, R; Gomez Garrido, B; Lorenzo, SM; Lopez-Mahia, P; Prada, D and Macias, F (2002) Environmental fate and behavior of HCH isomers in a soil-plant system in a contaminated site. Organohalogen Compounds 59: 307-310

[73] Fletcher, JS and Hedge, RS (1995) Release of phenols by perennial plant roots and their potential importance in bioremediation. Chemosphere 31: 3009-3016

[74] Yoshitomi, KJ and Shann, JR (2001) Corn (Zea mays L.): root exudates and their impact on 14C-pyrene mineralization. Soil Biology and Biochemistry 33: 1769-1776

[75] Singer, AC; Crowley, DE and Thompson, IP (2003) Secondary plant metabolites in phytoremediation and biotransformation. Trends in Biotechnology 21: 123-130

[76] Valant-Vetschera, KM; Roitman, JN and Wollenweber, E (2003) Chemodiversity of exudates flavonoids in some members of the Lamiaceae. Biochemical Systematics and Ecology 31: 1279-1289

[77] Chaudhry, Q; Blom-Zandstra, M; Gupta, S and Joner, EJ (2005) Utilising the synergy between plants and rhizosphere microorganisms to enhance breakdown of organic pollutants in the environment. Environmental Science and Pollution Research 12: 34-48

[78] Singh, N (2003) Enhanced degradation of hexachlorocyclohexane isomers in rhizosphere soil of Kochia sp. Bulletin of Environmental Contamination and Toxicology 70: 775-782

[79] Phillips, TM; Seech, AG; Trevors, JT and Piazza, M (2000) Bioremediation of soils containing hexachlorocyclohexane, in Wickramanayake, GB; Gavaskar, AR; Gibbs, JT and Means JL Eds., Case Studies in the Remediation of Chlorinated and Recalcitrant Compounds. Battelle Press, Columbus, OH, USA, pp. 285-292

[80] Schwitzguébel, JP (2001) Hype of hope: the potential of phytoremediation as an emerging green technology. Remediation 11(4): 63-78

[81] Van der Lelie, D; Schwitzguébel, JP; Glass, DJ; Vangronsveld, J and Baker, A (2001) Assessing phytoremediation's progress in the United States and Europe. Environmental Science and Technology 35: 446A-452A

[82] Schwitzguébel, JP; Van der Lelie, D; Baker, A; Glass, DJ and Vangronsveld, J (2002) Phytoremediation: European and American trends, success, obstacles and needs. Journal of Soils and Sediments 2: 91-99

[83] Singhal, V and Rai, JPN (2003) Biogas production from water hyacinth and channel grass used for phytoremediation of industrial effluents. Bioresource Technology 86: 221-225

[84] Schwitzguébel, JP (2004) Potential of phytoremediation, an emerging green technology: European trends and outlook. Proceedings of the Indian National Science Academy B70: 131-152

Was this article helpful?

0 0
Home Detox

Home Detox

Never before revealed. Home Detox - Step By Step Guide To Dextoxify The Body. Has too much late night behavior and partying got you feeling bad about yourself? Are you trying to lose weight but nothing is happening? Maybe you are just sick of all of the toxins that are in the air you breathe, the water you drink and the foods you eat. If so, then you need to do something about it. If you find yourself feeling bad about your health, there are ways that you can help your body right at home.

Get My Free Ebook

Post a comment