RESEARCH ARTICLE

Evaluation of hexachlorocyclohexane contaminationfrom the last lindane production plant operating in India

Simran Jit & Mandeep Dadhwal & Hansi Kumari & Swati Jindal & Jasvinder Kaur &

Pushp Lata & Neha Niharika & Devi Lal & Nidhi Garg & Sanjay Kumar Gupta &

Pooja Sharma & Kiran Bala & Ajaib Singh & John Vijgen & Roland Weber & Rup Lal

Received: 31 January 2010 /Accepted: 3 October 2010 /Published online: 22 October 2010# Springer-Verlag 2010

AbstractPurpose α-Hexachlorocyclohexane (HCH), β-HCH, andlindane (γ-HCH) were listed as persistent organic pollutantsby the Stockholm Convention in 2009 and hence must bephased out and their wastes/stockpiles eliminated. At the lastoperating lindane manufacturing unit, we conducted a prelim-inary evaluation of HCH contamination levels in soil andwater samples collected around the production area and thevicinity of a major dumpsite to inform the design of processesfor an appropriate implementation of the Convention.Methods Soil and water samples on and around theproduction site and a major waste dumpsite were measuredfor HCH levels.Results All soil samples taken at the lindane production facilityand dumpsite and in their vicinity were contaminated with an

isomer pattern characteristic of HCH production waste. At thedumpsite surface samples contained up to 450 gkg−1 Σ HCHsuggesting that the waste HCH isomers were simply dumpedat this location. Ground water in the vicinity and river waterwas found to be contaminated with 0.2 to 0.4 mgl−1 of HCHwaste isomers. The total quantity of deposited HCH wastesfrom the lindane production unit was estimated at between36,000 and 54,000 t.Conclusions The contamination levels in ground and riverwater suggest significant run-off from the dumped HCHwastes and contamination of drinking water resources. Theextent of dumping urgently needs to be assessed regarding therisks to human and ecosystem health. A plan for securing thewaste isomers needs to be developed and implementedtogether with a plan for their final elimination. As part of the

Responsible editors: Roland Weber, Mats Tysklind, Caroline Gaus

This article belongs to the series “Dioxin and POP Contaminated sites”edited by Roland Weber, Mats Tysklind, and Caroline Gaus.

Electronic supplementary material The online version of this article(doi:10.1007/s11356-010-0401-4) contains supplementary material,which is available to authorized users.

S. Jit :H. Kumari : S. Jindal : J. Kaur : P. Lata :N. Niharika :D. Lal :N. Garg : P. Sharma :K. Bala :R. Lal (*)Department of Zoology, University of Delhi,Delhi 110007, Indiae-mail: ruplal@gmail.com

R. WeberPOPs Environmental Consulting,Ulmenstrasse 3,73035 Goeppingen, Germany

J. VijgenInternational HCH and Pesticides Association,Elmevej 14,2840 Holte, Denmark

M. DadhwalLaboratoire Interactions, Ecotoxicologie, BiodiversiteÉcosystémes (LIEBE)-CNRS, Université Paul Verlaine—Metz,Metz, France

S. K. GuptaDepartment of Anatomical Sciences & Neurobiology,University of Louisville, School of Medicine,500 South Preston Street, Room 916A,Louisville, KY 40202, USA

A. SinghDepartment of Zoology, Sri Venkateswara College,University of Delhi,New Delhi 110021, India

Environ Sci Pollut Res (2011) 18:586–597DOI 10.1007/s11356-010-0401-4

assessment, any polychlorinated dibenzo-p-dioxins anddibenzofurans (PCDD/PCDF) generated during HCH recy-cling operations need to be monitored.

Keywords Hexachlorocyclohexane (HCH) . HCHdumpsite . Lindane . Persistent organic pollutant (POPs) .

Stockholm Convention

1 Background, aim, and scope

Technical hexachlorocylohexane1 and the purified gammaisomer of HCH2 (lindane3) were historically among themost intensively produced and used pesticides. Globalcontamination has resulted from this manufacture and use(Breivik et al. 1999; Li 1999; Vijgen 2006). In theproduction of technical HCH eight isomers are formedwith the following distribution: α- (+/−) (60–70%), β- (10–12%), γ- (10–12%), δ- (6–10%), ε- (3–4%) and η- and θ-HCH (<2%; Willet et al. 1998). Two formulations of HCH,i.e., technical HCH (the production reaction mixture) andlindane were widely used. Lindane replaced the use oftechnical HCH in late 1950s–60s in most industrialcountries and in 1991 in China. Based on the reactionstoichiometry (one ton production of lindane generates 8 to12 t of HCH waste isomers; Vijgen 2006), it is estimatedthat the total global usage of lindane has resulted in 4 to 7million tons of HCH waste being generated (Vijgen 2006;Vijgen et al. 2010). The production of HCH and thedumping of HCH waste isomers have resulted in numerouspersistent organic pollutants (POPs) contaminated sitesaround the world (Weber et al. 2008a, b). Severe contam-ination has been reported, for example, from productionfacilities in Rio de Janeiro (Brazil; Oliveira et al. 2003),Pontevedra (Spain; Concha-Grana et al. 2006; Vega et al.2007), Bilbao (Spain; Mohn et al. 2006), Chemnitz(Germany; Boltner et al. 2005), Carolina (United States;http://www.earthfax.com/Whiterot/PCP.htm) and Bitterfeld(Germany; Kalbitz and Popp 1999; Weber et al. 2008a, b).These contaminated sites are now acting as reservoirs fromwhich the deposited HCH isomers (mainly α-HCH and β-HCH) will continue to leach and volatilize into theenvironment for decades or even centuries if appropriatecountermeasures are not taken (Vijgen et al. 2010).

Based on their environmental properties, the Conferenceof Parties to the Stockholm Convention designated α-HCH,β-HCH, and lindane (γ-HCH) as POPs in the StockholmConvention in May 2009 (UNEP 2009; Vijgen et al. 2010)and they were officially listed as POPs in Annex A to the

Convention as of 26 August 2009. Accordingly, these POPsneed to be phased out and their wastes/stockpiles need to beeliminated in an environmentally safe manner (StockholmConvention 2001). A few exemptions have been listed forapplications of lindane under the provisions of theConvention for the treatment of head lice and scabies(UNEP 2009). For these purposes, continued production oflindane is allowed.

In India, technical HCH was extensively used from the1960s until 1997. During this period, around 1 million tonswas produced but after this time it was subject to a nationalban. Subsequently, lindane (the only HCH isomer withinsecticidal properties) replaced technical HCH in agriculturaland pharmaceutical formulations. According to nationalstatistics, approximately 6,856 t of lindane was produced inIndia for both national consumption and export during theperiod 1995–2009 (Department of Chemicals and Petrochem-icals, India 2009). Assuming 8 to 12 t of waste isomers perton of lindane, it can be estimated that anywhere between56,000 and 84,000 t of HCH waste could have beengenerated in the last 15 years.

In other countries where lindane has been produced,disposal of waste HCH has resulted in very significantenvironmental contamination of large areas of land. In viewof this, it was considered that the impact of manufacturingoperations in India needed urgent characterization andevaluation. As a first step in this process, soil and watersamples from lindane production unit and its environs wereanalyzed. This focus was prompted by a recent study onphytoremediation of HCH residues in which HCH contam-ination was detected in soil close to the lindane producingfacility (Abhilash et al. 2008; Abhilash and Singh 2009).Maximum Σ HCH (sum total of α-, β-, γ-, and δ-HCH)concentration reported in the soil sampled in this study was100 mgkg−1. The reported isomer pattern (α-HCH: 70–77%, β-HCH: 8–16.5%, and γ-HCH: 5–13%) in thecontaminated soils, however, did not appear to be typicalof residues from HCH production.

In the present study, HCH contamination in soil andwater samples collected from the premises and from areasin the vicinity of production facility was analyzed. Inaddition a major dumpsite and area surrounding it was alsosampled. Several thousand tons of HCH isomers (i.e., POPswaste) are known to have been deposited at this locationduring the past 10 years. The HCH isomer patterns presentwere used to infer the contamination sources and history. Inaddition experiences and insights gained from study ofother facilities where production, disposal, and recycling ofwaste isomers has taken place were used to assess thecurrent situation of lindane production unit and to definethe management and remediation measures indicated underthe terms of the Stockholm Convention for the site and itssurroundings.

1 CAS Registry No. 608-73-12 γ-HCH is the only insecticidally active isomer.3 CAS Registry No. 58-89-9

Environ Sci Pollut Res (2011) 18:586–597 587

2 Materials and methods

2.1 Lindane factory unit and a related main HCH wasteisomer dumpsite

The last lindane manufacturing units that has been engaged inlindane production since 1997 was selected to survey HCHcontamination. It is situated 25 km north-east of the Lucknowrailway station (26° 54′ N and 81° 4′ E; Fig. 1; SupportingInformation Figs. 1 and 2a). The waste HCH isomersremaining after lindane separation have been (and continueto be) stored temporarily in the so-called muck yard behindthe factory (Supporting Information Fig. 1). Periodically theaccumulated HCH waste is removed and transported toseveral different dumpsites. Several relatively small dump-sites have been discovered in the locality while a major HCHdumpsite (27°00′ N and 81°09′ E) is located 13 km awayfrom the lindane manufacturing unit on Deva Road atUmmari village, Barabanki, UP, India (Fig. 2; SupportingInformation Figs. 1 and 2). This latter site was selected for apreliminary screening. The dumpsite (Fig. 2; SupportingInformation Fig. 2) is comprised of an open area of 1,356 m2

with a deposition depth4 of approximately 2 m. An adjacentarea once used for a brick kiln has an area of around 988 m2

which has been partly mined for clay to depths of up to 6 m.At another suspected dumpsite 1.2 km south of the lindanemanufacturing unit, samples could not be collected.

2.2 Collection of soil and water samples

Soil samples were collected using a sampling auger andsealed for transportation to laboratory. Samples from highcontamination region were stored separately from lowcontamination samples. Water samples were collected insterile bottles. Most samples were collected during 2006. Afew additional samples were collected in October 2009(water samples in rivers).

The soil and water samples were collected from three areas:

(A) Premises and surrounding area of the facility and theinterim storage (“muck yard”; IP1 to IP11 and LN5 to 7):

Eleven soil samples were collected from the prem-ises of the industry. All soil samples were collectedfrom a depth of 0–0.20 m. Samples IP1, IP2, and IP3were collected from close to the muck yard of lindaneproduction unit (Fig. 1). The other samples (IP5 toIP11) were collected from the factory surroundings withsamples IP4 and IP6 taken about 3 and 4 km away fromthe muck yard of lindane production unit. A watersample (LN5) was taken from a small drainage channel

which carried run-off from the HCH manufacturingunit, flowing finally into the Sharda River where furthersamples (LN6 and LN7) were taken (Fig. 1). HCHmuck was also collected from the lindane productionunit’s muck yard (Supporting Information Fig. 2).

(B) Main HCH dumpsite and surrounding area (UM1 toUM17 and LN8):

The investigated dumpsite is located close to Ummarivillage (13 km north-east from the factory). For thesurvey of HCH residues at this location, 17 surface soilsamples were collected. The monitored area on andaround the HCH dumpsite can be divided into threezones (Fig. 2; Supporting Information Fig. 2): Zone Arepresented the actual dumpsite comprising of the opendumpsite and an old brick kiln location covering a totalarea of 2,344 m2. Zone B was an agricultural field(600×250 m2) and zone C was a barren land withcattle and goats grazing (20×40 m2). From zone A,UM1 represented the center of the open dumpsite (0–0.20 and 0.20–0.40 m) and UM2 (0.20, 0.20–0.40,0.40–0.60, and 0.60–0.80 m) from the former brickkiln area using a sampling auger. Three water samples(LN1–LN3) were taken from stagnant rainwater at thedumpsite. A single sample of ground water was takenby hand pump from a well at 10 m depth (LN4) and asample was also obtained from the drainage system atthe back of the dumpsite (LN8; Fig. 2).

(C) Road connecting the lindane production unit and furthersuspected dumpsite (zone D; UM18 to UM25 and LN9):

Zone D soil samples (UM18–UM25) were collectedalong the road running between the factory and a sitewhere it was suspected that HCH wastes had beendumped (Supporting information Fig. 1). A few weretaken close to the dumpsite at a distance of 50 to 250 m(UM18–UM22) while two samples were collected at adistance of 2 and 4.5 km respectively along the road(UM23 and UM24). Another sample of soil (UM25)was also collected from a point located 7.5 km south ofthis suspected site. A water sample (LN9, SupportingInformation Fig. 1) was collected from the ReethaRiver 3.7 km from the site.

2.3 Extraction of HCH residues from soil and watersamples and HCH “muck”

The collected soil samples were thoroughly ground,homogenized, and sieved through fine mesh after dryingat room temperature for 2 days. The extraction and analysisof HCH residues was carried out according to the methoddescribed by Concha-Grana et al. (2006). Briefly, 1 g of theeach sample (in triplicate) was extracted in 20 ml of solventconsisting of hexane/acetone (1:1, v/v) by sonication for

4 The deposition depth was estimated by interviewing people living inthe area.

588 Environ Sci Pollut Res (2011) 18:586–597

5 min with 30 s interval at a power of 6 W. The extract wascentrifuged at 2,000×g for 2 min to obtain a clean solventphase. This was then dried and the obtained residues (HCHresidues) were dissolved in appropriate volumes of ethylacetate (2 ml for Zones B, C, and D samples and as muchas 10 ml for Zone A samples). This was passed through apre-activated alumina and anhydrous sodium sulfate col-umn (10 cm length, 2 cm internal diameter) and eluted with20 ml ethyl acetate. The filtrate was again dried in aRotavap (Buchi, Switzerland) and subsequently dissolvedin appropriate volume of ethyl acetate.

Efficiency of extraction procedure was checked byrecovery experiments conducted with spiked soil samplesin triplicates. Uncontaminated garden soil sample (1 g) wasspiked with HCH isomers at a concentration level of200 μgg−1 and extracted by the same method. The sameunspiked soil served as the blank and processed along thesamples.

For extraction of HCH residues from water samples100 ml of water sample was placed in a separation funneland extracted twice with equal volumes of hexane for3 min. The two extracts were combined and concentratedby using Rotavap. This concentrated extract was passedthrough anhydrous Na2SO4 in a glass column plugged withglass wool at the bottom (10 cm length, 2 cm internaldiameter). The eluate was again dried and dissolved in 1 mlhexane. Recovery of the method was checked by process-ing 100 ml of tap water sample that was spiked withtechnical HCH at a concentration of 2 μgml−1. Along withtriplicates of experimental and recovery the blank tap watersamples was also processed.

Samples that were collected from the muck yard wereextracted (100 mg) in 10 ml acetone by vortexing for 1 min.The dried extract was then dissolved in 2 ml ethyl acetate.

2.4 Analysis of HCH residues from soil, water,and the storage site

As the concentration of HCH isomers were estimated basedon calibration against external standards of HCH isomers(α-, β-, γ- and δ-HCH), the samples were serially dilutedin the range of standards to allow reliable estimations. Allsamples were analyzed by gas chromatograph (GC17-A,Shimadzu, Japan) equipped with electron capture 63Nidetector and contained a 30 m Rtx-50 column (Restek,

UM 5

Farmer house

UM 11

UM 6

UM 8

UM 7

UM 9

UM 10

UM 13UM 12

UM 14

UM 15

(HCH dump site)

LN4

LN8

UM 5

Farmer house

UM 11

UM 6

UM 8

UM 7

UM 9

UM 10

UM 13UM 12

U

(HCH dump site)

LN4

LN8 Zone B(Agricultural fields)

UM 5

Farmer house

UM 11

UM 6

UM 8

UM 7

UM 9

UM 10

UM 13UM 12

U

(HCH dump site)

LN4

LN8

UM 5

Farmer house

UM 11

UM 6

UM 8

UM 7

UM 9

UM 10

UM 13UM 12

U

(HCH dump site)

LN4

LN8

UM 5

Farmer house

UM 11

UM 6

UM 8

UM 7

UM 9

UM 10

UM 13UM 12

U

(HCH dump site)

LN4

LN8

UM 5

Farmer house

UM 11

UM 6

UM 8

UM 7

UM 9

UM 10

UM 13UM 12

U

(HCH dump site)

LN4

LN8

UM 5

UM16

Farmer house

Brick kiln UM2

UM 11

UM 6

UM 8

UM 7

UM 9

UM 10

UM 13UM 12

(HCH dump site)

LN4

LN8

UM 5

UM17

Farmer house

Zone A

Zone C

(Barren land)

UM1UM3

UM 11

UM 6

UM 8

UM 7

UM 9

UM 10

UM 13UM 12

(HCH dump site)

LN4

LN8 Zone B(Agricultural fields)

Fig. 2 Map showing the systematic scheme of the HCH dumpsite andcategorized surrounding area (not in scale) and soil (filled circle) andwater sample (filled upright triangle) locations. The HCH dumpsiteand surrounding areas were divided into three zones, zone A (HCHdumpsite), zone B (agricultural field with farmer house), and zone C(barren land with grazing cattle). In total 18 soil samples werecollected from these three zones for HCH residue analysis at 0–0.20 mdepth. UM1 was from the center of the HCH dumpsite at two depths0.20 m and between 0.20 and 0.40 m. UM2 was collected from thebrick kiln at four depths 0.20 m, 0.20–0.40 m, 0.40–0.60 m and 0.60–0.80 m. Three stagnant rain water samples were collected from zone Aand B (LN1–3). One ground water sample from a hand pump (LN4)and another from the drainage (LN8) in zone B were also collected

Fig. 1 Sampling map of soil(filled circle) and water samples(filled upright triangle) collectedaround the lindane productionunit. In total, 11 soil sampleswere collected for HCH residuesanalysis. IP1 and IP2 were col-lected from 100 m distancebehind the muck yard of lindaneproduction unit and IP3 was justbehind the muck yard. IP4 was4 km away from the muck yardof lindane production unit. LN5was collected from a smalldrainage channel and two watersamples (LN6 and 7) from theSharda River

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USA) with an internal diameter of 0.32 mm and phasethickness of 0.25μm. The column, injector, and detectortemperatures were maintained at 200, 220, and 250°C,respectively. The flow rate of the carrier gas (N2) wasconstant at 0.9 ml/min.

The protocols followed showed recovery of 75 to 80%for soil samples while for water samples it was 70 to 72%.The relative standard deviation varied from 14.4 to 4.1 incase of soil samples and for water samples 7.4 to 10.4.

3 Results and discussion

Thirty six soil samples and nine water samples werecollected for HCH residue analysis from the vicinity ofthe production site of lindane producing unit (Fig. 1;Supporting Information Fig. 2A) and from the majordumpsite used for disposal of waste HCH residues/isomers.HCH isomer ratios obtained from the suite of analysesconducted were used to infer the source(s) of contamina-tion. Differences in the isomeric profiles found were alsoused in attempts to discover whether the contamination wasof recent origin or represented historic activities. The α-HCH:γ-HCH isomer ratio has been used in a number ofstudies as an index of degradation and aging in areascontaminated by application of technical HCH (Hong et al.2005; Kim et al. 2002). The α-HCH:γ-HCH ratio cannot beused in this way, however, for wastes arising frommanufacture of lindane since preferential extraction of theγ-isomer means that such residues are comprised largely ofα-, β-, and δ- HCH. It has been observed that lindaneproduction generates two waste fractions. A bulk wastefraction contains mainly α-HCH and β-HCH while asecond minor waste fraction contains both of these isomers,but in addition considerable concentrations of δ- HCH andγ-HCH also (Sievers and Friesel 1989). Hence, the ratio of

α-HCH:β-HCH (around six in technical HCH) can be usedto study the fate of dumped HCH (Kim et al. 2002) whilethe concentrations of δ- HCH also give valuable informa-tion. Accordingly, by considering the different isomericdegradation rates coupled with different water solubilitiesand volatilities it is possible to use HCH isomeric ratios toinform meaningful interpretations of contamination sourcesand histories arising from lindane manufacture.

3.1 Contamination and run-off from the production area

In all soil samples at the lindane production unit premisesand around the production area, HCH isomers weredetected and quantified (Table 1). Maximum residueconcentrations of Σ HCH (4.3×103 mgkg−1 of soil) wasfound in sample IP1 collected from the area rear of thelindane production unit close to the area used for theintermediate storage of the waste HCH isomers. Soilsample from a rice field adjoining the industrial area(sample IP10) was found to contain Σ HCH residues of12.7 mgkg−1 (Table 1). Most of the 11 soil samplescollected from the premises of the lindane production unitand the rice field showed a distinct isomer pattern withpredominance of α- and β-HCH while δ- and γ-HCHisomers were detected only in trace amounts (Table 1). Thisisomer distribution strongly suggests that the contaminationarose exclusively from disposal of waste HCH isomersgenerated during the manufacture of lindane. In one soilsample (IP4) taken some distance from the plant, the δ-isomer was found in comparable concentration to that of α-HCH indicating that the factory may have generated a“delta paste” from a second refining step which was thentaken off-site for disposal (Sievers and Friesel 1989).Although the refining step may still be a feature ofoperations at the plant, the overall low Σ HCH levels(4.23 mgkg−1) found in sample IP4 suggest that this

Samples HCH isomers (mgkg−1 of soil) Σ-HCHa (mgkg−1 soil)

α β γ δ

IP1 4068 119.6 14.3 50 4251.9

IP2 5 6.9 nd nd 11.9

1P3 47.3 3 0.5 nd 50.8

1P4 1.9 0.5 nd 1.83 4.23

1P5 0.4 16.4 nd nd 16.8

1P6 22.3 11.4 nd nd 33.7

1P7 42.2 0.9 nd nd 43.1

1P8 11.2 2.8 0.08 0.014 14.1

IP9 6.5 1.9 nd nd 8.4

IP10 10.2 2.5 nd nd 12.7

IP11 2.1 nd nd nd 2.1

Table 1 Results of residue anal-ysis of soil samples collectedfrom the surrounding area oflindane production unit,Chinhat, Lucknow

Values are mean of three replicateanalysis

nd not detecteda Sum total ofα-,β-, γ-, and δ-HCH

590 Environ Sci Pollut Res (2011) 18:586–597

fraction does not contribute significantly to soil contami-nation in the areas considered in this study.

The water in the drainage channel (LN5) adjacent to thelindane production plant was found to be heavily contaminatedwith HCH residues (Σ HCH: 24 mgl−1). In this sample, theisomer profile differed significantly from those found in thesoil samples and showed an extremely high δ-HCHconcentration (10.8 mgl−1) with a significant contributionfrom, γ-HCH (5.5 mgl−1) and much lower concentrations ofα-HCH (5.4) and β-HCH (2.46). This cannot be explainedsimply in terms of the significantly different water solubilityof the various isomers (Table 2). Indeed, the concentrations ofα-HCH and β-HCH are considerably above the known watersolubilities of these isomers. The oversaturated state of thewater from the drainage channel with respect to these isomersmay be due to the concomitant presence of solvents orsurfactants. For example, methanol used in the separation ofisomers in lindane production may have been spilled into thechannel. Alternatively, HCH isomers may have been presentin a colloidal phase (Persson et al. 2008) or fine particles.Nonetheless, the overall isomer pattern found provides furtherevidence of a second refining step taking place on site. Itseems likely that residues generated from this (delta paste),which are known to contain high δ-HCH and significant γ-HCH (Sievers and Friesel 1989), have been directly releasedinto the drainage system.

The drainage system finally discharges into a river (theSharda River). A water sample taken from the river belowthe discharge point (sample LN6) was found to contain0.22 mgl−1 of Σ HCH with 0.13 mgl−1 α-HCH and0.09 mgl−1 β-HCH. This isomeric profile indicates that thedrainage water with its predominantly delta-paste patternwas not having a significant inflow effect on the isomericpattern present in the river. This was further illustrated by ariver water sample taken upstream of the production unit(sample LN7) which showed similar contaminant concen-tration levels and isomer pattern. This is indicative ofcontamination of the river by waste isomer deposits furtherupstream.

The isomer pattern found in soil and water around theproduction site in the present study was found to besignificantly different from the pattern reported by Abhilashet al. (2008) and Abhilash and Singh (2009) in their

phytoremediation study conducted in another field close tolindane production unit. In all soil sample analyses reportedby these workers and which were taken from a single area, β-HCH was the dominant isomer present together withsignificant concentrations of γ-HCH. This suggests that theHCH contamination present in the area they investigated wasmost probably attributable to application of (or contaminationby) technical HCH, coupled with an isomeric pattern shiftarising from faster degradation and desorption rates of α-HCH compared to β-HCH and γ-HCH. Stored HCH wastefrom the lindane manufacturing process collected directlyfrom the interim storage (supporting information Figure 2)contained predominantly α-, β-, and δ-HCH isomers. Theproportions of the individual HCH isomers varied from 76%to 86% for α-HCH, 7–15% for β-HCH, 5–7% for δ-HCHwith γ-HCH comprising 2.2–2.4% of the waste.

3.2 Soil and groundwater contaminationin and around the major lindane production unit dumpsite

Results of residue analysis from samples taken in andaround the HCH dumpsite are shown in Table 3. This areawas found to be highly contaminated with HCH residues(Fig. 2). On the dumpsite itself (Zone A) the topmost layersampled (0–0.20 m depth) was found to contain 338 gkg−1

of Σ HCH (Sample UM1, Table 3). A surface (0–0.20 m)sample taken in the adjacent area formerly used for brickproduction contained 450 gkg−1 Σ HCH (UM2). Thesesamples revealed that at these major dumpsite areas nomeasures had been taken to cover the surface of the site andthat materials were simply dumped there. At this site, asimple “core sample” was taken to a depth of 0.80 m. Theconcentration of Σ HCH at 0.80 m was 125 gkg−1

indicating a mixing of HCH muck with other materialpresent on the site. Taken together, the variation in HCHconcentrations with depth and the higher concentration inthe top layer may indicate that multiple dumping operationshave taken place and that some attempts may have beenmade to cover deposits with layers of soil as a primitiveform of management and securing of these wastes.

Based on a preliminary assessment done by consideringlevels of contamination together with the overall spatialextent of the dump site it was estimated that some 4,700 tof HCH waste could have been deposited in these two areasalone.

In both the deposits, α- and β- HCH were present atsimilar concentrations (Table 4) indicating a significantdegradation (and possibly additional leaching) of the moredegradable and water soluble α-HCH isomer (see: Table 2).This suggests that the dumpsite has not received fresh HCHwaste from approximately 2005 onwards.

Zone B, an agricultural field adjoining the main dump-site, showed Σ HCH to be present in soils at concentrations

Table 2 Water solubility and dipole moment of relevant HCHisomers (from Weil et al. 1974)

HCH Isomer Water solubility (mg/l; 25°C) Dipole moment (Debye)

α-HCH 2 2.22

β-HCH 0.2 0

γ-HCH 7.8 2.8–3.6

δ-HCH 31.4 2.2–2.3

Environ Sci Pollut Res (2011) 18:586–597 591

between 4 and 1,900 mgkg−1. Most of the samples alsocontained α- and β-HCH at similar concentrations andexhibited an isomer pattern comparable to that found on thedumpsite itself. This may indicate significant wind erosionand aeolian transport of HCH from the unsecured dumpsiteto relatively uncontaminated external environments.

Samples taken from Zone C, an area of relatively barrenground which was is use as rough grazing for cattle showeda maximum concentration of Σ HCH of 57 mgkg−1 of soil.Cattle may ingest soil as they feed and there exists,therefore, a direct pathway whereby HCH isomers couldbe taken up by these animals and, as a result, subsequentlyenter the human food chain.

Transport of HCH wastes from the production facility tothe dumpsites in open trucks raises the possibility ofcontamination along the routes used. To investigate this,samples were collected from the roadside close to the dumpsite (Samples UM18 to 25) and these showed soil

concentrations of Σ HCH between 50 and 127 mgkg−1

indicating some contamination from transport activities.Higher Σ HCH soil contamination levels of 300 mgkg−1

(Sample UM23) at a distance of 2 km and 700 mgkg−1 at adistance of 7.5 km (Sample UM25) from the dumpsite wereobtained. These roadside samples might have beenexpected to show these decreasing levels of contaminationfrom truck transport activities with increasing distance fromthe plant. The α-HCH:β-HCH ratio of less than one inthese two more highly contaminated samples, however,indicates that this contamination may have occurred someyears ago and might, therefore, be due to historical wastedumping activities in these locations or along the road. Thesample UM25 was taken just in front of a recently builtschool and the high concentrations found at this potentiallysensitive location on terms of potential human exposurerequires further urgent investigations and assessment of therisk involved.

Table 3 HCH residue analysis for samples from the area surrounding the HCH dumpsite Ummari village, Barabanki, UP

Zones Samples HCH isomers (mgkg−1 of soil) Σ-HCHa (mgkg−1 of soil) α/β

α β γ δ

A UM1 1.76×105 1.62×105 nd nd 3.38×105 1.08

UM2 2.35×105 2.19×105 nd nd 4.5×105 1.07

UM3 1.36×105 0.83×105 nd nd 2.19×105 1.62

B UM4 53.75 39.81 nd nd 93.56 1.35

UM5 293.3 330 nd nd 623.3 0.88

UM6 70.4 30.2 nd nd 100.6 2.33

UM7 87.77 50.66 nd nd 138.43 1.73

UM8 1.9 1.6 0.01 0.04 3.55 1.18

UM9 60.67 53.16 nd nd 113.83 1.14

UM10 60.14 62.4 nd nd 122.54 0.96

UM11 261.3 87.3 nd nd 348.6 2.99

UM12 72.67 57.92 nd nd 130.59 1.25

UM13 3.1 1.7 0.23 nd 5.03 1.82

UM14 23.22 20.91 nd 1 45.13 1.11

UM15 1396 458 nd nd 1854 3.04

C UM16 1.5 1.1 nd nd 2.6 1.36

UM17 48.6 8.35 nd nd 56.95 5.8

D UM18 25.3 23.23 nd nd 48.53 1.08

UM19 73.49 53.93 nd nd 127.42 1.36

UM20 36.21 22.47 nd nd 58.68 1.61

UM21 27.5 23.38 nd nd 50.88 1.17

UM22 14.3 11.64 nd nd 25.94 1.22

UM23 0.53×102 2.54×102 nd nd 3.07×102 0.20

UM24 4.98 3.67 nd nd 8.65 1.35

UM25 3.4×102 3.59 102 nd nd 6.99×102 0.99

Values are mean of three replicate analysis

nd not detecteda Sum total of α-, β-, γ-, and δ-HCH

592 Environ Sci Pollut Res (2011) 18:586–597

A single ground water sample was taken near thedumpsite with a depth of approximately 10 m located inZone B. (Sample LN4; Table 4; Fig. 2). The ground watercontained 0.4 mgl−1 Σ HCH with α-HCH (0.22 mgl−1) andδ- HCH (0.18 mgl−1) HCH present at similar concentra-tions. This strongly suggests that HCH is leaching from thedumpsite into the ground water resources in the vicinity.These analyses also suggest that the more highly watersoluble isomers (Table 2) may be being preferentiallyleached. In addition, a water sample taken of water drainingfrom the site (Sample LN8) showed relatively high Σ HCHconcentrations at 10 mgl−1 with a α-HCH: β-HCH ratio of10:1. This most probably results from the significantlyhigher water solubility of α-HCH since the ratios in thesamples from the dump were close to 1 as noted above(Table 3). A water sample (Sample LN9) taken from theReetha River flowing at a distance of 3.7 km from thedumpsite contained 0.38 mgl−1 Σ HCH indicating contam-ination of the river from deposited waste HCH. α-HCHpredominated in this sample, possibly as a result ofpreferential solubility of this isomer. Ground water andwater taken from the Reetha River are important waterresources in the area. They both provide potable water forthe local populace. Both water resources contained HCHresidues approx. 100 times higher than the permissiblelimits of 0.003 mgl−1 (Council for European Communities1980).

Contamination of Indian bottled water and cold drinkswith HCH residues have been reported on a number ofoccasions (Bakore et al. 2004; Mathur et al. 2003; Prakashet al. 2004). In most cases, bottled water samples werefound to contain stable β-HCH together with trace amountsof other isomers. Such findings reflect a broad problem ofHCH contamination in India most likely as a result of theapplication of approximately one million tons of technicalHCH over the last four decades or so. The current study, asa preliminary investigation of the lindane production unitsite suggests that the shift to lindane production and use isresulting in significant contamination of soils and waterresources around the production site and through thedumping of extracted isomers which are subsequentlydumped in unsecured locations.

3.3 Extent of waste isomer production, recycling of wastesand the possibility of PCDD/PCDF contaminationat lindane production unit

There is no publicly available report on the total HCHresidues generated or stored at the lindane production unit.However a rough approximation can be made by estimatingtotal lindane production and the amount of waste known tobe generated in such processes. It has been reported thatlindane production unit utilizes its production capacity of300 t in full to produce lindane (CAPE 2005) which is usedin various formulations. Thus, it can be broadly estimatedthat between 1995 and 2009 this manufacturing unit couldhave produced a maximum of around 4500 t of lindanegenerating as a result approximately 45,000 t (36,000 to54,000 t) HCH waste containing mainly α- and β-HCHPOPs waste.

Based on the preliminary assessment of one of the maindumpsites reported here on the basis of consideration ofcontamination detected and the spatial extent of the site, itis estimated that approximately 4,700 t of HCH muck hasbeen deposited at this dumpsite. This estimate accounts foronly a minor share of maximum expected waste isomersproduced by the lindane production unit over the specifiedproduction period. Even allowing for several thousand tonsof HCH waste in the intermediate storage area at theproduction facility it seems clear that other significantdumpsites exist whose locations are not currently known.One such suspected area exists at the location where sampleUM25 was taken in this study and where a school has nowbeen constructed. Another suspect area exists 1.2 km southof the lindane production unit (see Supporting InformationFig. 1).

Another uncertainty to a detailed estimate of the totalamount of production waste disposed of by productionfacility is that the company has recycled some of the HCHwastes to produce trichlorobenzene (CAPE 2005). The

Table 4 Residue analyses of water samples collected from surround-ing area of lindane production unitand HCH dumpsite

Samples HCH isomers (mgl−1 of water) Σ-HCHa (mgl−1of water)

α β γ δ

LN1 1.2 0.92 nd nd 2.12

LN2 0.3 nd nd nd 0.3

LN3 nd 0.03 nd nd 0.03

LN4 0.22 nd nd 0.18 0.4

LN5 5.4 2.46 5.5 10.8 24.16

LN6 0.13 0.09 nd nd 0.22

LN7 0.13 0.09 nd nd 0.22

LN8 8.84 0.82 0.04 1 10.7

LN9 0.29 0.09 nd nd 0.38

Water samples LN1, 2 and 3 are from stagnant rain water on HCHdumpsite and surrounding areas. LN4 was a ground water samplefrom the dumpsite. LN5 was a water sample from the small drainageat the lindane production unit. LN6 was a water sample from theSharda River upstream of lindane production unitwhereas LN7 is fromdownstream of the unit. LN8 is from drainage at the dumpsite andLN9 is from Reetha River

Values are mean of three replicates

nd not detecteda Sum total of α-, β-, γ-, and δ-HCH

Environ Sci Pollut Res (2011) 18:586–597 593

current company product portfolio5 still includes commer-cial grade trichlorobenzene (TriCBz) and 1,2,4-TriCBztogether with onward reaction products such as 2,4,5-trichloroaniline, 1,2,4-trichloro-5-nitrobenzene (http://www.indiapesticideslimited.com/products.html). Experience inGermany has shown that such recycling of HCH intotrichlorobenzenes resulted in the unintentional generationof PCDD/PCDF at high concentration. The resultingcontamination from these unintentionally produced POPscontributed to the closure of the plant (Jürgens and Roth1989; Sievers and Friesel 1989; Weber et al. 2006 and2008b). Accordingly, there is an urgent need to evaluatePCDD/PCDF contamination at the lindane production plantand disposal sites.

3.4 Past policy and necessary future policy framesconsidering Stockholm Convention implementationrequirements

It seems that the current unacceptable situation arose as aresult of poor regulation and enforcement of waste disposalpractices in relation to HCH in India. In addition, basedupon observation, there appeared to be no change in thewaste management and dumping practices of the companyafter HCH was accepted as a POP by the Conference ofParties in May 2009. Accordingly, enforcement by thegovernment and the competent authority in line with theStockholm Convention commitments made by India is ofurgent importance if the current situation is to improve.

The following are, in our opinion important urgentaction points, and also necessities for the implementation ofthe Stockholm Convention

& If the company continues production of lindane for thepermitted uses listed as exemptions in the StockholmConvention (e.g. head lice and scabies) then the wastemanagement practices at the company need to beurgently and significantly improved.

& With the designation of α- and β-HCH isomers in theStockholm Convention these co-produced waste iso-mers are classified as POPs waste and need to be treatedin accordance with the Stockholm Convention require-ments. In this respect, the recycling of POPs waste isprohibited by Article 6 of the Convention.

& In order to ensure environmentally sound managementof current and historical HCH waste production, it willbe necessary for the factory to establish appropriatedestruction capacity or to arrange for shipment overseasto dedicated hazardous waste management plants,

capable of handling POPs waste. In the case ofdeveloping local disposal capacity, appropriate Envi-ronmental Impact Assessment procedures, controlled bythe regulatory agencies, will need to be implemented toensure compliance with national and internationalregulatory requirements.

& Furthermore, as a matter of urgency, a detailedassessment program should be devised and directed atevaluating and documenting details of the two largecontaminated sites described in this paper. This shouldalso address identification and characterisation of otherlocations used as HCH dumpsites used by the company.Additional elements should include a full risk assess-ment of the population living in the vicinity of thefactory and the dumpsites. Evaluation of contaminationof the food chain, of drinking water and of the peopleliving and working in the area should be carried out.This assessment should include, in addition to HCHisomers, also PCDD/PCDF and other unintentionalPOPs and other hazardous products from the current/historic production portfolio including degradationproducts.

The dimension and urgency of the contaminationrequires (in our opinion) that the Indian governmentaddress the case and the HCH POPs stockpiles as a priorityin an updated National Implementation Plan.

3.5 Preliminary studies on degradation and remediationof HCH contamination at the site

We have recently reported on the presence of HCHdegrading microorganisms in the HCH dumpsite investi-gated in this current study (Dadhwal et al. 2009). Thepresence of HCH degrading microorganisms in HCHcontaining dumpsites has also been reported from Germanyand Spain (Boltner et al. 2005; Mohn et al. 2006). In anongoing effort to develop bioremediation technologies, thegenetics and biochemistry of HCH degradation in sphingo-monads has been widely explored (Kumari et al. 2002;Dogra et al. 2004; Suar et al. 2004; Suar et al. 2005; Lal etal. 2006; Lal et al. 2010; Sharma et al. 2006; Raina et al.2008a). In these studies, bioremediation via biostimulation(Dadhwal et al. 2009) and bioaugmentation (Raina et al.2008a) of soils with Σ HCH levels ranging from 70 to280 mgkg−1 has been demonstrated. Over 80% of the α-and γ-HCH was degraded together with significantamounts of the more stable β- and δ-HCH. Overall, ΣHCH levels were reduced to <30% of the original levels in24 days and to less than 3% in 240 days using ex situbiostimulation techniques. In other studies by Abhilash andSingh (2009) results indicating phytoremediation activity ata site contaminated by HCH close to the factory has been

5 Additionally even hexachlorobenzene (HCB) is offered here ascommercial product although it is listed as POP in the StockholmConvention.

594 Environ Sci Pollut Res (2011) 18:586–597

reported. While bioremediation or phytoremediationapproaches may have potential in addressing HCH con-taminated sites it will be necessary to understand fully thelimitations of such approaches.

Not only will the practical feasibility of these “soft”remediation methods need to be demonstrated but athorough knowledge of degradation products and theirtoxicity is necessary (Weber et al. 2008b; Andersson et al.2009). For example, the detection of several metabolites ofHCH isomers (pentachlorocyclohexanols, pentachlorocy-clohexenes and tetrachlorocyclohexane-diols) have beenreported some of them with significantly higher watersolubility and therefore mobility as compared to the parentHCHs (Raina et al. 2007, 2008b).

4 Conclusion

Widespread HCH contamination has been documented atthe premises of the lindane production unit and in thevicinity of the production plant and at one of the majordumpsites used by the company. The prevalence of α-HCHand β-HCH together with the absence of γ-HCH revealedthat the contamination originates from manufacture oflindane with the related waste isomers. The ratios of theisomers present were used to interpret deposition timingand practice. Most of the soil samples at the production siteshowed a high α-HCH/β-HCH ratio indicating recentcontamination. The α-HCH/β-HCH ratio of the soilsamples on and around the dumpsite was around 1indicating that the deposition activities were not veryrecent.

High concentrations of HCH residues in the top layer ofthe dumpsite reveal that this site has not been covered orsecured by any means to at least minimize direct winderosion and rain water run-off critical during the monsoonseason. In addition, flooding events are expecting to

increase and intensify with climate change (Wölz et al.2008).

~PHCH values of 450 gkg−1 for the topsoil of the

dumpsite reported in this study were between 10 and10,000 times higher as compared to contamination levelsreported from similar HCH deposits in other countries(Table 5).

HCH contamination in soils from neighboring areas andin ground drainage and river water samples revealed thatHCH waste is being mobilized, probably via wind actionand water run-off from the interim storage area and fromthe dumpsites. As a result, these wastes are contaminatingadjacent agricultural fields, together with ground water andriver water from two rivers in the vicinity which is utilizedfor drinking water. Considering the tens and thousands oftons of stored and dumped POPs waste represented by theseHCH isomers from this manufacturer, such mobilizationcould lead to widespread POPs contamination of the widerenvironment. If proper measures are not taken, therefore, tomanage the wastes and remediate these contaminated sitesthey will represent a significant risk to health of thepopulation living locally but also possible over a muchwider area. Accordingly, to mitigate the risks posed bythese wastes there is an urgent need to identify andcharacterize all sites affected by the disposal of the manythousands of tons of wastes originating from production ofHCH at the lindane production unit. Subsequently, thesesites will need to be urgently secured to stop contaminationof agricultural lands residential areas, and water resources.Further steps will need to be taken to develop andimplement a plan for elimination of the waste isomers.

In addition, possible recycling of HCH to trichloro-benzene at the lindane production site may have resultedin highly PCDD/PCDF-contaminated residues. Therefore,the residues and the deposits including the relatedleachates should be assessed for PCDD/PCDF and otherunintentionally produced POPs content and releases assoon as possible

Country Maximum HCH residues (mgkg−1 of soil) Σ HCH Reference

α β γ δ

Brazil 6200 7320 140 530 14,190 Oliveira et al. 2003

Canada 18000 1800 4000 1300 25,100 Phillips et al. 2005

Germany – – – – 191,144 Vijgen et al. 2006

Sievers and Friesel 1989

Spain 59215 41357.5 61.1 353.4 100,987 Vega et al. 2007

Concha-Grana et al. 2006

Calvelo-Pereira et al. 2006

USA – – – – 83,628 Phillips et al. 2005

India 176000 162000 n. d. n. d. 338,000 This study

Table 5 Maximum total HCHreported in HCH dumpsites/industrial waste sites fromvarious other locations

Environ Sci Pollut Res (2011) 18:586–597 595

Acknowledgments This work was supported by grants fromDepartment of Biotechnology (DBT) and National Bureau ofAgricultural Important Microorganisms (NBAIM), and DU/DST-PURSE Grant Government of India. S Jit, JK, NN, DL, NGacknowledge Council of Scientific Research and Industrial Research(CSIR), Govt. of India and S Jindal, PS, KB, PL acknowledgeDepartment of Biotechnology (DBT), Govt. of India for providing theresearch fellowship. We also gratefully acknowledge Dr. SudhirKumar and Faizan Haider (Lucknow University, India) for their helpin sample collection.

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