Temporal Distribution of Organochlorine Pesticides in Tissues of Two Fish Species of Tropical Reservoirs: A Case Study of Bui, Ghana

This study analysed tissues distribution of organochlorine pesticides (OCPs) of Alestes nurse and Chrysichthys nigrodigitatus from Bui Reservoir on temporal basis from June, 2017 to May, 2018. GC-ECD was used to identify, quantify pesticide residues. Sixteen OCPs were detected in A. nurse while 14 in C. nigrodigitatus, concentrations range from1.0 – 194.20 ng/g-ww in A. nurse and from1.01 – 370.97 ng/g-ww in C. nigrodigitatus. Among HCHs, α-HCH and γ-HCH dominated in the gonads of A. nurse and C. nigrodigitatus with highest of 156.55 ± 37.65 ng/g-ww and 347.48 ± 23.49 ng/g-ww respectively. In DDTs group methoxychlor and ρ’ρ’DDT predominated in the gonads of A. nurse and C. nigrodigitatus with 25.5 ± 7 ng/g-ww and 9.05 ± 0.8 ng/g-ww respectively. Of cyclodienes endrin II and aldrin were the dominants in gonads (73.5 ± 65.4 ng/g-ww) and gills (26.10 ± 0.17 ng/g-ww) of A. nurse and C. nigrodigitatus respectively. No significant difference (p>0.05) in OCP concentrations among tissues but there were significant differences (p<0.05) among seasons with wet season accounting for the highest. Results show the use of muscle tissue was adequate in terms of monitoring OCPs in fish while distribution of OCPs were associated with climatic conditions in addition to their chemical properties. Keywords: cyclodienes; dichlorodiphenyltrichloroethanes hexachlorocyclohexanes; meteorological pollutants; temporal