Sedimentary Records of DDT and HCH in the Pearl River Delta, South China
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- 作者：Gan Zhang ; Andrew Parker ; Alan House ; Bixian Mai ; Xiangdong Li ; Yuehui Kang ; and Zhishi Wang
- 刊名：Environmental Science & Technology
- 出版年：2002
- 出版时间：September 1, 2002
- 年：2002
- 卷：36
- 期：17
- 页码：3671 - 3677
- 全文大小：412K
- 年卷期：v.36,no.17(September 1, 2002)
- ISSN：1520-5851
文摘
Tropical regions in developing countries are thought to besignificant sources of organochlorine pesticides in theglobal context, owing to high rate of use and only a recentproduction ban or restriction on application of thesepesticides. In the present paper, DDT and HCH in eight 210Pb-dated sedimentary cores from the Pearl River Delta,South China, were analyzed in order to reconstruct the timetrends of these persistent organic pollutants in thistropical region. The sedimentary inventories of 
DDT andHCH through the cores ranged from 36.6 to 1109.5 ng/cm2 and from 11.2 to 226.3 ng/cm2, respectively, and theirspatial distribution implies that the water flows from theHumen, Jiaomen, Hongqili, and Hengmen outlets rather thanthe Xijiang flow from Modaomen outlet, supplied themajor historical input of DDT to the estuary. Although aproduction ban of technical HCH and DDT was imposed inChina in 1983, their sedimentary fluxes display increasingtrends or strong rebounds in the 1990s as recorded inthe core profiles, characteristic of the increasing ratios of(DDE + DDD)/DDT and DDE/DDT. It is suggested that anenhanced land soil runoff in the process of large-scale landtransform, as well as a higher river water flow in early1990s, had mobilized these pesticides from soil to thesedimentary system in the region.
DDT andHCH through the cores ranged from 36.6 to 1109.5 ng/cm2 and from 11.2 to 226.3 ng/cm2, respectively, and theirspatial distribution implies that the water flows from theHumen, Jiaomen, Hongqili, and Hengmen outlets rather thanthe Xijiang flow from Modaomen outlet, supplied themajor historical input of DDT to the estuary. Although aproduction ban of technical HCH and DDT was imposed inChina in 1983, their sedimentary fluxes display increasingtrends or strong rebounds in the 1990s as recorded inthe core profiles, characteristic of the increasing ratios of(DDE + DDD)/DDT and DDE/DDT. It is suggested that anenhanced land soil runoff in the process of large-scale landtransform, as well as a higher river water flow in early1990s, had mobilized these pesticides from soil to thesedimentary system in the region.