Abstract:
West Lake (Ho Tay) is the largest freshlake in Hanoi, Vietnam. It has a surface area of ≈ 500 ha and a total volume of
>10 7 m3, and is 1–3.5 m in depth. West Lake has been classified as needing protection because of its valuable freshwater
genetic resources. Noting that it has been extensively affected by pollution, the objective of the present study was to
examine the extent of heavy metal contamination of the sediments and commercially important biota in the lake. Heavy
metal concentrations in the sediment from most of 24 samples in West Lake exceeded the Ontario Ministry of Environment
Screening Level for chromium (Cr), copper (Cu), manganese (Mn), lead (Pb) and zinc (Zn) concentrations. Aquatic
organisms from the lake also were found to be contaminated by heavy metals. The average Zn concentrations in snails and
mussels tissues ranged between 174 and 415 μg g–1, and the Pb concentrations between 3.5 and 5.2 μg g–1. The Cu
concentration in shrimp (52 μg g–1) and snail (189 μg g–1), and the Pb concentration in all fish species and shrimp from the
lake (2.0–5.2 μg g–1) exceeded the Food Standard Australia-New Zealand (FSANZ) health standards for human consumption.
The Cd concentration in Cyprinus carpio also exceeded the FSANZ standard. The implications of these study findings for
the effective management of the food and ecological resources of West Lake are discussed.
