Organochlorine Pesticides in Callinectes Pallidus (Rochebrune, 1883) and Penaeus Monodon (Fabricius, 1798) from Lagos Lagoon and Badagry Creek, Lagos, Southwest Nigeria

Abstract

Organochlorine pesticides (OCPs) have been of great concern around the world owing to their chronic toxicity, persistence and bio-accumulation in aquatic organisms. The OCP concentrations were measured in water, sediment and shell fishes (Panaeus monodon and Callinectes pallidus) in Lagos State (Lagos lagoon and Badagry creek), between November 2018 and June 2019. The samples were analyzed for Alpha (HCH), Beta (HCH), Gamma (HCH), Delta (HCH), Heptachlor, Aldrin, Heptachlor epoxide, Gamma chlordane, Endosulfan1 Alpha chlordane, Dieldrin, DDE, DDD, DDT, Endrin, Endosulfan II, Endrin Aldehyde, Endosulfan sulfate, Endrin ketone and Methoxychlor. The detection and determination of the pesticide residues were carried out by Gas chromatography with electron capture detector. The mean concentration of OCPs in water samples ranged from 0.150 ± 0.012µg/l (Alpha HCH) to 147.60 ± 10.810 µg/l (Endosufan II). The level of OCPs in sediment ranged from 0.150 ± 0.012 µg/kg (Alpha HCH) in Lagos lagoon to 243.500 ± 138.000 µg/kg (ppDDT) in Badagry creek. The highest mean concentration of OCPs in water and sediments were recorded in Lagos lagoon. The Concentration for shell fish ranged from 0.250 ± 0.009 µg/kg (Alpha HCH) in Lagos lagoon to 67.380 ± 22.860 µg/kg (Endosulfan II) in Badagry creek for Callinectes pallidus and from 1.310 ± 0.210 µg/kg (alpha HCH) to 143.500 ± 71.892 µg/kg (Eldrin Aldehyde) in Badagry creek for Penaeus monodon.  Methoxychlor, Lindane and Aldrin were the commonly detected compounds in all the samples from both water bodies. The results showed that OCP levels in all shellfish samples analyzed were above the maximum acceptable limits of 0.01ppm (10 µg/kg) set by EU and Federal Ministry of Environment for aquatic life protection. The highest value was recorded in Penaeus monodon in Badagry creek. Indicating an urgent need for the monitoring of these pesticide residues in water, commercially important food species and the environment, as this will go a long way towards preventing various environmental and public health hazards.