Abstract Soil samples collected randomly from the provinces of Tayninh and Songbe, southwestern Vietnam, were analysed for the presence of DDTs, HCHs and PCBs. Residues of these chemicals were detected in all the analysed samples. Concentrations of σ DDT in cultivated soil samples were relatively high with the highest level of 290 ng/g. However, non-cultivated soil samples recorded lower levels of σ DDT. On the other hand, concentrations of σ HCH were low ranging from 0.09 to 2.3 ng/g in cultivated and from 0.09 to 2.1 ng/g in non-cultivated soils, respectively. Maximum concentrations of PCBs were recorded with the highest level of 150 ng/g in a cultivated soil sample. As for non-cultivated soil samples, the highest level was found in a former U. S. air base grounds. It can then be implied that the PCBs were incorporated in the arms used by allied forces during the Second Indochina War.
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