Instituto Argentino de Oceanografía (IADO), CCT-CONICET, Bahía Blanca, Argentina.
Environ Monit Assess. 2011 Jan;172(1-4):17-32. doi: 10.1007/s10661-010-1315-9. Epub 2010 Feb 6.
Forty-nine superficial sediment samples used in this study were collected from eight sites in the Bahia Blanca Estuary, located in the Buenos Aires Province southwest, Argentina, in a period between April 2005 and March 2009, to assess the concentration levels, spatial and seasonal distribution, and putative input sources of 18 selected organochlorine pesticides (OCs), following UNEP-IAEA procedures. Average concentration levels in sediments ranged between 3.54 and 63.79 ng g⁻¹, d.w. (mean = 15.99 ng g⁻¹, d.w.), for ∑OCs, and from nondetectable to 8.03 ng g⁻¹, d.w. (mean = 2.16 ng g⁻¹, d.w.), and from nondetectable to 3.20 ng g⁻¹ (mean = 0.97 ng g⁻¹, d.w.) for hexachlorocyclohexanes (HCHs) and dichlorodiphenyltrichloroethanes (DDTs), respectively. Principal component analysis allowed the classification of sampling sites according to the main OCs inputs over the estuary. In comparison to other worldwide locations and to the world coastal sediment concentrations range, sediment DDTs and HCHs levels were in the low range; on the opposite, ∑OCs average was in the medium range. OCs seasonal distribution was found to be highly correlated with the precipitations seasonality and sowing seasons in the adjacent agriculture fields. In addition, an ecotoxicological risk assessment pointed industrial and agriculture catchment zones with intermediate probability of adverse effects to biota, while the city sewage outfall was classified with none indication of an immediate threat. Data indicated that the estuary sediments were functioning as a sink for persistent OC pesticides (either in use or banned), however, it was found a declining trend on their environmental burden.
本研究采集了位于阿根廷布宜诺斯艾利斯省西南部 Bahia Blanca 河口的 8 个地点的 49 个表层沉积物样本，以评估 18 种选定的有机氯农药 (OCs) 的浓度水平、空间和季节性分布以及可能的输入源。这些样本是在 2005 年 4 月至 2009 年 3 月期间采集的。采用 UNEP-IAEA 程序进行分析。沉积物中∑OCs 的平均浓度范围为 3.54 至 63.79ng g⁻¹（平均值为 15.99ng g⁻¹），HCHs 和 DDTs 的浓度范围分别为未检出至 8.03ng g⁻¹（平均值为 2.16ng g⁻¹）和未检出至 3.20ng g⁻¹（平均值为 0.97ng g⁻¹）。主成分分析允许根据河口主要 OCs 输入对采样地点进行分类。与其他全球地点和世界沿海沉积物浓度范围相比，沉积物 DDTs 和 HCHs 水平处于低水平；相反，∑OCs 的平均值处于中等水平。OCs 的季节性分布与降水的季节性和附近农田的播种季节高度相关。此外，生态毒理学风险评估指出，工业和农业集水区存在对生物群产生不利影响的中等可能性，而城市污水排放口则没有立即威胁的迹象。数据表明，河口沉积物是持久性有机氯农药（无论是否在使用中）的汇，但它们的环境负担呈下降趋势。
