Lindane in soil

Lopez-Avila et al. [36] used a stable isotope dilution gas chromatography-mass spectrometric technique to determine down to O.lppb of pentachlorophenol (also Atrazine, Diazinon and lindane) in soil. Soil samples are extracted with acetone and hexane. Analysis is performed by high-resolution gas chromatography-mass spectrometry with mass spectrometer operated in the selected ion monitoring mode. Accuracy greater than 86% and a precision better than 8% were demonstrated by use of spiked samples. 

The isotope dilution gas chromatography-mass spectrometry method described by Lopez-Avila et al. [16] and fully discussed in section 5.3.1.3, has been applied to the determination of 0.1 1pg kg-1 Lindane in soil. Accuracy was greater than 86% and precision better than 8%. 

Yule, W.N., Chiba, M., and Morley, H.V. Fate of insecticide residnes. Decomposition of lindane in soil. J. Agric. Food Chem., 15(6) 1000-1004, 1967. 

S.B. Mbabazi, (1998). Levels of lindane in soil, plants, and selected soil fauna in a sprayed in maize agroecosystem. M.Sc. Thesis, Makerere University, Kampala, Uganda. 

Soil. Lindane degraded rapidly in flooded rice soils (Raghu and MacRae, 1966). In moist soils, lindane biodegraded to (y-PCCH) (Eisner et al., 1972 Kearney and Kaufman, 1976 Fuhremann and Lichtenstein, 1980). Under anaerobic conditions, degradation by soil bacteria yielded y-BTC and a-BHC (Kobayashi and Rittman, 1982). Other reported biodegradation products include pentachlorocyclohexane, pentachlorobenzene, tetrachlorocyclohex-l-enes, and tetrachloro-benzenes (Moore and Ramamoorthy, 1984). Incubation of lindane for 6 wk in a sandy loam soil under flooded conditions yielded y-TCCH, y-2,3,4,5,6-pentachlorocyclohex-l-ene, and small amounts of 1,2,4-trichlorobenzene, 1,2,3,4-tetrachlorobenzene, 1,2,3,5-, and/or 1,2,4,5-tetrachloro-benzene (Mathur and Saha, 1975). Incubation of lindane in moist soil for 8 wk yielded the follow-... 

Microorganisms isolated from a loamy sand soil degraded lindane and some of the metabolites identified were pentachlorobenzene, 1,2,4,5-tetrachlorobenzene, 1,2,3,5-tetrachlorobenzene, y-PCCH, y-TCCH and p-3,4,5,6-tetrachloro-l-cyclohexane (p-TCCH) (Tu, 1976). y-PCCH was also reported as a metabolite of lindane in an Ontario soil that was pretreated with jo,//-DDT, dieldrin, lindane, and heptachlor (Yule et ah, 1967). The reported half-life in soil is 266 d (Jury et al., 1987). 

Indigenous microbes in soil partially degraded lindane to carbon dioxide (MacRae et al., 1967). In a 42-d experiment, C-labeled lindane applied to soil-water suspensions under aerobic and anaerobic conditions gave CO2 yields of 1.9 and 3.0%, respectively (Scheunert et al., 1987). 

In a moist Hatboro silt loam, volatilization yields of 50 and 90% were found after 6 h and 6 d, respectively. In a dry Norfolk sand loam, 12% volatilization was reported after 50 h (Glotfelty et al., 1984). The average half-lives for lindane in aerobic and flooded soils under laboratory conditions were 276 and 114 d, respectively (Mathur and Saha, 1977). In field soils, the half-lives ranged from 88 d to 3.2 yr with an average half-life of 426 d (Lichtenstein and Schulz, 1959, 1959a Lichtenstein et al., 1971 Voerman and Besemer, 1975 Mathur and Saha, 1977). 

Plant Lindane appeared to be metabolized by several grasses to hexachlorobenzene and a-BHC, the latter isomerizing to p BHC (Steinwandter, 1978 Steinwandter and Schluter, 1978). Oat plants were grown in two soils treated with [ CJlindane. 2,4,5-Trichlorophenol and possibly y-PCCH were identified in soils but no other compounds other than lindane were identified in the oat roots or tops (Fuhremann and Lichtenstein, 1980). The half-life of lindane in alfalfa was 3.3 d (Treece and Ware, 1965). 

Albanis, T.A., Pomonis, P.J., and Sdoukos, A.T. The influence of fly ash on pesticide fate in the environment. I. Hydrolysis, degradation and adsorption of lindane in aqueous mixtures of soil with fly ash, Toxicol Environ. Chem., 19(3-r4) 161-169, 1989. 

Lindane attacks the nervous system causing trembling, loss of coordination, paralysis, and ultimately death. Lindane was often applied as a spray on crops, where it would be either ingested or inhaled. Initially its environmental persistence was considered an asset, but eventually that was seen as a liability and led to restrictions in it use. Lindane is stable in water and has an average half-life of 15 months in soil. It is also highly toxic to fish trout are affected at levels as low as 1.7 J.g of lindane per liter of water. The US EPA restricted its use in 1983, as have most European countries. However, it continues to be used to treat seeds and is used in products to control head lice. In the US over 200,000 pounds are used each year to treat seeds prior to planting. 

Example 3a) Estimate Koc and Kd for lindane in a soil containing 4% organic carbon using the log Kow value of 3.721isted in Table 8.7. 

Oomen AG, Sips A, Groten JP, Sijm D, Tolls J. 2000. Mobilization of PCBs and lindane from soil during in vitro digestion and their distribution among bile salt micelles and proteins of human digestive fluid and the soil. Environ Sci Technol 34 297-303. 

Lindane has been shown to have a low soil binding affinity. Therefore, it may be mobile in soils with especially low organic matter content or subject to high rainfall and pose a risk of groundwater contamination. Lindane is highly persistent in most soils, with a field half-life of 15 months. 

Pentachlorophenol and lindane were selected primarily because they were reported to be the least mobile chemicals in fact, based on their octanol/water partition coefficients, it was expected that these chemicals would not leach at all. These chemicals were spiked into the soil at 16.2 ppm and were leached for 30 days with organics-free water at a rate of 55.8 mL/day. Results are presented as amount leached versus time and concentration of chemical in soil at various depths in soil column. Furthermore, mass balances are presented for each chemical. Subsequent sections present the experimental details and the results of this experiment. 

Following equilibration with soil, the aqueous solution was separated by centrifugation at 2,800 rpm and was analyzed directly by high-pressure liquid chromatography (HPLC). The experimental conditions for HPLC analysis are given in Reference 21. Attempts to analyze lindane in the aqueous phase by HPLC with ultraviolet detection, without preconcentration, were unsuccessful. Lindane was analyzed by gas chromatography with electron capture detection following preconcentration on Cjg-reverse phase resin and elution with tetrahydrofuran. Other details can be found in Reference 21. 

Figure 4. Distribution of lindane and pentachlorophenol in soil following the 30-day test (column I).

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