Distribution of Lindane in Water, Sediment, and Fish from the Warri River of the Niger Delta, Nigeria

This paper is the first attempt to quantify the levels and the distribution pattern of lindane in the surface water, sediment and fish (Chrysichthys furcatus and Tilapia zilli). The samples were collected from three stations (Ovwian, Ekakpamre, and Ovu) of the Warri River in the western Niger Delta of Nigeria in 2006: during the dry (January-April) and wet seasons (May-August). The analysis included a total of 96 samples made up of 24 samples each for water, sediment, and fish. The pesticide levels were analysed using high performance liquid chromatography to elucidate its distribution in various environmental compartments. Residue levels in the matrices ranged from below the detection limit (BDL) to 1.37μg L-1 in water, BDL to 12.66 μg g-1 dry weight (dw) in sediment, BDL to 16.67 μg g-1dw in Chrysichthys furcatus, and BDL to 0.15 μg g-1dw in Tilapia zilli. The observed values were above the ecological benchmarks (0.01 μg L-1) recommended by the Nigerian Environmental Protection Agency and European Union. They were also relatively higher than in previous studies on the Nigerian environment, which calls for regular monitoring of the Niger Delta water bodies. Istražene su pojava i raspodjela lindana u površinskoj vodi, sedimentu i dvije vrste riba Chrysichthys furcatus i Tilapia zilli iz rijeke Warri u zapadnom dijelu delte Nigera (Nigerija). Uzorci su skupljeni 2006. godine na tri postaje (Ovwian, Ekakpamre i Ovu) tijekom sušne (siječanj - travanj) i vlažne sezone (svibanj - kolovoz). Analizirano je ukupno 96 uzoraka: po 24 uzorka vode, sedimenta i riba. Razine pesticida određene su primjenom tekućinske kromatografije visoke djelotvornosti (HPLC) te je utvrđivana njihova raspodjela u različitim dijelovima okoliša. Koncentracije rezidua u uzorcima vode bile su u rasponu: ispod granice detekcije (BDL) do 1,37 μg L-1, u sedimentu: BDL do 12,66 μg g-1 suhe tvari, u ribama Chrysichthys furcatus: BDL do 16,67 μg g-1 suhe tvari te Tilapia zilli: BDL do 0,15 μg g-1 suhe tvari. Određene vrijednosti bile su ispod graničnih vrijednosti (0,01 μg L-1) propisanih od Nigerijske uprave za zaštitu okoliša i Europske unije. Kako su dobivene vrijednosti bile relativno više u odnosu na podatke iz ranijih istraživanja okoliša u Nigeriji, istaknuta je potreba trajnog monitoringa vodotoka u delti Nigera.