Fate of Aldrin and Dieldrin in Nanumba-North Municipality, Ghana
The aim of this study was to assess the levels of contamination of aldrin and dieldrin in the Nanumba-North Municipality of the Northern Region of Ghana. Gas Chromatography equipped with electron capture detector (GC-ECD) was used to analyse the samples. In all, 148 samples were analysed, consisting ten (10) soil samples, 108 water samples and 30 food crop items. The study revealed the presence of aldrin and dieldrin at varying mean concentrations, with dieldrin recording significant concentrations in the samples. Aldrin was the least frequently detected residue in the soil samples, and occupied 30% with a mean value of 0.003 ± 0.001 µg/L. On the other hand, dieldrin occupied 70% with a mean value of 0.007 ± 0.004 µg/L. The trends of aldrin and dieldrin residues distribution in water samples from the various depths indicated frequent occurrence and higher residue concentrations in water samples at depths 30 cm and below than depths 15-30 cm and 0-15 cm. The presence of aldrin and dieldrin in the water samples could be traced to wind drift or atmospheric transport of volatilized pesticides, direct overspray, direct spillage, pesticide misuse by farmers, run-off and leaching from application fields and surrounding areas during and after their applications. The concentrations of aldrin and dieldrin residues in the samples analysed were generally low and below the WHO (2017) MRLs. Therefore, food crops analysed in the study area will not pose any significant threat to the food industry as far as shipment to other parts of the world is concerned. Besides, aldrin and dieldrin detected showed significant differences at p < 0.05. However, just because there are low levels does not mean that consumers will not be exposed to its health risks. Since continuous availability can lead to bioaccumulation and biomagnification through the food chain. The study, therefore, recommends that in order to reduce environmental contamination and to protect both wildlife and human health appropriate authorities in the area should instil means to enlighten pesticides users on the best way of sustainable pest control methods as well as implementing integrated pest management strategies that can magnify the ambition of worthwhile environmental conditions.
Keywords: Aldrin; dieldrin; metabolites; Nanumba-North Municipality; GC-ECD
