| Article ID | Journal | Published Year | Pages | File Type |
|---|---|---|---|---|
| 4412722 | Chemosphere | 2009 | 6 Pages |
Historical α-hexachlorocyclohexane (α-HCH) budget in Taihu Lake (TL), China has been simulated by a Gridded Basin-based Pesticide Mass Balance Model (GB-PMBM). Using annual usage of α-HCH from 1952 to 1984 as input, the model outputs included annual concentrations in air, water and sediment in TL, and annual cumulative burden of α-HCH in the lake water and sediment from 1952 to 2008. Model results showed that the modeled α-HCH in the air, water and sediment matched their corresponding measured data well, and the current levels of α-HCH in the air, water and sediment in TL in 2008 are 11.7 (3.4–22.7) pg m−3, 0.8 (0.3–1.5) ng L−1 and 0.18 (0.04–0.46) ng g−1 dw (dry weight), respectively. The α-HCH burden in TL water started to accumulate after 1952, reached the highest value of 11 000 kg in 1972, decreased very quickly since the beginning of 1980s, reduced to 200 kg in 1984 and 3 kg in 2008. It was found that TL water played a role of “distributor” in process of transport of α-HCH. Before 1980, TL water took a large amount of α-HCH from atmosphere through a huge air–water interface and carried a major portion of it out of the lake through water current. After 1980, TL water took α-HCH from lake sediments and river water entering the lake, and released almost all of it to air. The lake water itself cannot hold a large portion of the chemical due to its shallow depth and short residence time.
