?VARIATION OF HEAVY METAL CONCENTRATIONS IN WATER AND FRESHWATER FISH IN NIGER DELTA WATERS - A CASE STUDY OF BENIN RIVER. Pakistan Journal of Scientific & Industrial Research [Internet]. 2003 Dec. 22 [cited 2026 Mar. 10];46(6):439-42. Available from: https://v2.pjsir.org/index.php/biological-sciences/article/view/1697