DDT and HCH residues in dairy milk samples collected from different geographical regions of India: a multicentre study

Under a multicentre study conducted by the Indian Council of Medical Resear ch, 2205 samples of dairy milk weve collected from rural and urban areas of 12 states representing different geographical regions of India. These samp les were analysed for residues of DDT and different isomers of HCH by gas-l iquid chromatography. Analytical quality assurance between various particip ating laboratories was ensured through analysis of check samples. The resid ues of DDT and HCH were detected in move than 80% of samples analysed. Conc entrations of DDT residues, alpha-HCH, beta-HCH, gamma-HCH and delta-HCH ex ceeded their maximum residue limits prescribed by the Ministry of Health an d Family Welfare of the Indian Government in 37, 21, 42, 28 and 4% of the s amples, respectively. Median values of DDT and HCH found in dairy milk in I ndia were more than the corresponding values reported from most other count ries. The results showed significant variations in the incidence as well as level of these contaminants in dairy milk from different regions of the co untry.