Leaching lindane

Lindane 0.0002 0.0002 Liver or kidney problems Runoff/leaching from insecticide used on catttle, lumber, gardens... 

Results of volatilization and leaching estimations are reported for six pesticides that span a wide range of the physical/chemical properties that affect fate at the soil/air interface. The pesticides are Mirex, toxaphene, methoxychlor, lindane, malathion, and dibromochloropropane (DBCP). These particular pesticides were chosen for discussion here because they illustrate the methods for assessing the fate of organics at the... 

Volatilization and leaching interact with each other and other fate processes. Two of the pesticides, DBCP and lindane, are discussed in some detail to illustrate some of the interactions. The other four are discussed only briefly. 

As an example, we can compare the solubility of lindane and 2,4-D pesticides with respect to their major loss pathways. The Ku values of these pesticides are 1.33 x 1CT4 and 5.5 x 10 9 mol L 1, respectively. In addition, the retardation coefficient or degree of sorption of lindane is much higher than that of 2,4-D. Therefore, 2,4-D is more likely to be leached, whereas lindane is more likely to remain near the soil surface from whichit can vaporize. Volatilization is thus the major pathway of lindane, and degradation and leaching are the major loss pathways of 2,4-D in the Asian environments. 

Meanwhile, the detection of a- ory-isomer HCH in relatively high concentrations when compared with other isomers suggest relatively little transformation of HCH or lindane, which are known to include up to 70% of ct-isomer and no less than 99% of y-isomer, respectively. On the whole this would suggest a loss or leaching from recently formed RPA or LPA. 

Our studies (Galiulin and Bashkin, 1996) accomplished in Klyazma and Ivan kovsk water reservoirs suggested loss or leaching of HCH and lindane in relatively little transformed form fromLPA because the oc- andy-isomers content was similar (Table I). The proportion of DDT in bottom sediments of the Klyazma river, tributaries of the Moskva and Oka rivers (Moscow region) was as (DDE + DDD)/DDT < 1, suggesting relatively little insecticide transformation in silts of bottom sediments. 

Pesticide wastes that are hazardous by reason of the characteristics are those which are either solvent based and have a flash point <60 °C are aqueous and have a pH <2.0 or >12.5 release HCN or H2S upon contact with acids or leach greater than threshold levels of one or more of the elements arsenic, barium, cadmium, chromium, lead, mercury, selenium and silver, or the pesticides endrin, lindane, methoxychlor, toxa-phene, 2,4-D or 2,4,5-TP. To date, these are the only pesticides for which thresholds have been established. 

Table I lists the EPA contaminants and the criteria that EPA has established to constitute a hazardous toxic waste. Table 2 shows the concentrations of the inorganic contaminants in the extract from the phosphogypsum samples. All of the organic compounds listed by EPA as hazardous toxic waste.s were tested by the standard EPA procedure none were detected. These included endrin, lindane, methoxychlor, toxaphene, 2,4-D silvex, and 2,4,5-TP silvex. All of the metals listed in Table I were found to be present in the extract at concentrations lower than allowed by EPA (as shown in Table 2). Therefore, by EPA definition phosphogypsum is not a hazardous toxic waste material. This confirms earlier research conclusions 71 that the leaching of trace elements from phosphogypsum is not significant in introducing hazardous toxic waste materials into the environment.

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. 

Leaching Experiment. Three polyethylene columns (4.8 cm ID by 50 cm height) ware employed to investigate the mobility of dicamba, 2,4-D, atrazine, diazinon, pentachlorophenol, and lindane. Each column was packed with 1,080g of fresh soil to a depth of 40 cm (sandy loam soil from Soils Incorporated, Puyallup, Washington pH 5.9 to 6.0 89 percent sand 7 percent silt 4 percent clay cation exchange capacity 7.5 meq/lOOg). 

Figure 10. Amount of lindane (/ig) leached from columns I, II III during the 30-day test.

Lindane was the fourth chemical to leach from the soil columns. The data shown in Figure 10 indicates that lindane was detected in the leachates collected from the three columns at day 18,... 

Groundwater. According to the U.S. EPA (1986), lindane has a high potential to leach to grormdwater... 

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