Variation of heavy metal levels in the tissues of Periophthalmus papillio from the mangrove swamps of the Bukuma oilfield, Rivers State

Abstract

The edible (muscles) and non-edible (viscera and gills) parts of Periophthalmus papillio inhabiting the mangrove swamps of the Bukuma oilfield and its environs in the Niger Delta area of Nigeria were analysed for Zn, Pb, Cd, Cu and Ni. The mean levels of heavy metals (µg/g dry wt.) in the edible parts ranged from Zn: 1.30-4.53; Pb 0.14-0.30; Cd ND-0.06; Cu 0.07 0.25 to Ni 0.07-0.16; non-edible parts Zn 1.05-2.31 Pb 0.18-0.46; Cd 0.03-0.14; Cu 0.05-0.24 to Ni 0.05-0.27. Apart from Zn that varied distinctly (P<0.05) between both tissues, all other metals do not, though they accumulated more in the non-edible parts. Generally elevated metal levels in both tissues were recorded at the stations with wellheads, implicating oil-related activities as the main source of contamination. However, the levels in the edible parts of P. pappilio may not pose any health risk to consumers, as they were lower than World Health Organisation (WHO) recommended levels in finfish for human consumption.

Keywords: mangrove swamp, oilfield, Periophthalmus papillio, Bukuma, Niger Delta

Global Journal of Pure and Applied Sciences Vol. 12(1) 2006: 89-92