HCH isomers, endosulfan, malathion, chlorpyrifos, and methyl-parathion were monitored in human milk samples from Bhopal, Madhya Pradesh. The endosulfan concentrations were highest and exceeded the S-HCH, chlorpyrifos, and malathion concentrations by 3.5-, 1.5-, and 8.4-fold, respectively. Through breast milk, infants consumed 8.6 times more endosulfan and 4.1 times more malathion than the average daily intake levels recommended by the World Health Organization. A correlation analysis (r values) between mothers' age and the content of the chemicals accumulated in breast milk indicated a substantial degree of correlation for malathion (r–0.5). The other chemicals showed low to negligible correlation with donor age.

Among the organochlorine pesticides, DDT and HCH excel in their broad spectrum toxicity and residual activity. However, developed countries have banned the usage of DDT since 1975, due to its inherent chemical stability, persistence, high liposolubility and bioaccumulation. Despite these undesirable properties, developing countries still use these insecticides primarly due to cost-benefit efficacy and broad spectrum toxicity. Also, it has been shown that both DDT and HCH have significantly shorter half lives in tropical environments than in temperate zones (Sleicher and Hoperaft, 1984, Samuel et al., 1988, Nair et al., 1992.In India, DDT and HCH contribute more than 70 percent of the total pesticide consumption. Hence, it becomes imperative to ascertain the extent of contamination in man. The aim of the present study was to assess the levels of DDT and HCH in breast milk, maternal serum and cord serum from mothers and their infants; to examine a possible correlation between them and finally to compare the extent of transfer of these chemicals by primigravidae and multigravidae donors to the newborn. Comparative data concerning all these parameters is lacking from the developing countries. MATERIALS AND METHODSSamples of maternal blood, breast milk and cord blood from 25 mothers (23.4 ± 1.085 years of age with range of 18-40 years) and their newborn from Irwin Hospital, Delhi constituted the study group. Donors were unemployed, non-smokers, on a vegetarian diet, belonging to a lower socio-economic class but healthy with no major illness in the recent past. Twelve donors were primigravidae while the remaining were multigravide.

Volatilization, mineralization, degradation and binding of soil‐applied [14C]DDT were studied in three different soils from a tropical region of southern India subjected to solar irradiation and flooding for a period of 42 days. The soil types–red cotton soil, nursery soil and canal bank soil–differed in their organic carbon content, pH and texture. Under unflooded conditions, volatile losses were highest in the sandy canal bank soil. Flooding significantly enhanced volatilization, and this effect was maximal in the nursery soil, which had the highest organic carbon. The soils fully exposed to solar radiations in quartz tubes registered 1.5‐1.8 times greater volatility. The volatilized organics contained appreciable quantities of DDE under both flooded and unflooded conditions. In addition, greater quantities of DDD volatilized from the flooded systems. The rate of formation of DDE was faster when soils were irradiated in quartz tubes. Mineralization remained minimal throughout the period of exposure and flooding the soil appeared to reduce further the [14C]carbon dioxide evolution. Canal bank soil exhibited the least mineralization and degradation. The data indicate that volatilization was significantly influenced by solar radiation and flooding to a much greater degree than by the differences in soil properties. Binding of DDT to soil was significantly increased by flooding the soil, thus leaving up to 33% of the initial DDT as bound residues in the nursery soil.

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1 Aldrin and dieldrin residues were monitored in the fat, breast milk and blood serum from female residents of Delhi. 2 The average aldrin and dieldrin contents were 0.048 and 0.099 ppb in adipose tissue, 0.003 and 0.060 ppb in breast milk and 0.004 and 0.002 ppb in blood serum, respectively. 3 The older donors contained higher levels of aldrin and dieldrin in their adipose tissue. 4 Primagravidae contained more of these chemicals in their breast milk. 5 A positive correlation was observed between the aldrin concentration in adipose tissue and breast milk, and that in adipose tissue and blood serum. Similarly, a significant correlation was found between dieldrin in adipose tissue and blood serum. 6 The levels of aldrin and dieldrin were low in samples from residents of Delhi when compared to those in developed countries.