title: Heavy metal accumulation in lake sediments, fish (Oreochromis niloticus and Serranochromis thumbergi), and crayfish (Cherax quadricarinatus) in Lake Itezhi-tezhi and Lake Kariba, Zambia.
abstract: We measured the level of heavy metal accumulation in lake sediments, herbivorous (Oreochromis niloticus) and carnivorous (Serranochromis thumbergi) fish, and crayfish (Cherax quadricarinatus) from Lake Itezhi-tezhi (ITT) and Lake Kariba. We used atomic absorption spectrophotometry to quantify the levels of seven heavy metals (Cr, Co, Cu, Zn, Cd, Pb, and Ni). The sediment and the herbivorous fish O. niloticus accumulated a very high concentration of Cu in Lake ITT, most likely due to the discharge of Cu waste from a mining area 450 km upstream. The aquatic species we sampled in Lake Kariba had higher concentrations of Cr, Ni, and Pb relative to those in Lake ITT. This is most likely due to anthropogenic activities, such as the use of leaded petrol and antifouling agents in marine paints. Interestingly, we observed a negative correlation between the coefficient of condition (K) and Ni concentration in the crayfish hepatopancreas. Both O. niloticus and the crayfish had much higher biota-sediment accumulation factors (BSAF) for Cu, Zn, and Cd relative to Cr, Co, Pb, and Ni. The rank of BSAF values for O. niloticus (Cu>Cd>Zn) and C. quadricarinatus (Zn>Cd>Cu) differed from the expected ranks based on the general order of affinity of metals (Cd>>Zn>Cu).
authors.affiliation: Laboratory of Toxicology, Department of Environmental Veterinary Sciences, Graduate School of Veterinary Medicine, Hokkaido University, Kita 18, Nishi 9, Kita-ku, Sapporo, 060-0818, Japan.
authors.forename: Shouta M M
authors.initials: SM
authors.lastname: Nakayama
authors.forename: Yoshinori
authors.initials: Y
authors.lastname: Ikenaka
authors.forename: Kaampwe
authors.initials: K
authors.lastname: Muzandu
authors.forename: Kennedy
authors.initials: K
authors.lastname: Choongo
authors.forename: Balazs
authors.initials: B
authors.lastname: Oroszlany
authors.forename: Hiroki
authors.initials: H
authors.lastname: Teraoka
authors.forename: Naoharu
authors.initials: N
authors.lastname: Mizuno
authors.forename: Mayumi
authors.initials: M
authors.lastname: Ishizuka
mesh_terms: D000818:Animals; D003400:Astacoidea / Q000378:metabolism*; D023681:Cichlids / Q000378:metabolism*; D004784:Environmental Monitoring; D005618:Fresh Water / Q000737:chemistry; D019015:Geologic Sediments / Q000737:chemistry*; D043143:Hepatopancreas / Q000378:metabolism; D008099:Liver / Q000378:metabolism; D019216:Metals, Heavy; D009132:Muscles / Q000378:metabolism; D014874:Water Pollutants, Chemical / Q000032:analysis*; D015024:Zambia
chemical_list: D019216:Metals, Heavy; D014874:Water Pollutants, Chemical