Department of Environmental Sciences, University of California, Riverside, California, USA.
Environ Toxicol Chem. 2013 Apr;32(5):1033-9. doi: 10.1002/etc.2161. Epub 2013 Mar 29.
Formulated sediments are recommended for use in toxicity tests to achieve standardized evaluations. However, the organic matter used in formulated sediments may differ qualitatively from that in natural sediments, which may lead to different chemical partition patterns and, hence, different toxicity effects. By deriving partition coefficients for organic carbon and dissolved organic carbon (K(OC) and K(DOC) , respectively) for eight pyrethroid insecticides from three formulated and five natural sediments, the authors characterized the differences between formulated and natural sediments in pesticide sorption. For all pyrethroids, the mean values of K(OC) and K(DOC) of formulated sediments were two to three, and three to 10 times smaller than those of natural sediments, respectively. The two formulated sediments containing α-cellulose or Manitoba peat showed significantly (p<0.0001) smaller K(OC) and K(DOC) values than natural sediments based on statistical analyses, while the difference was not significant for the formulated sediment containing New Brunswick peat. The K(OC) values were closely correlated (p<0.001) with soot carbon content, while the amount of carboxylic or phenolic functional groups may have affected K(DOC) . Therefore, the source and quality of organic matter are likely the most important factors in formulated sediments and must be standardized to provide consistency in sediment toxicity tests.
制定的沉积物被推荐用于毒性测试，以实现标准化评估。然而，制定沉积物中使用的有机物在质量上可能与天然沉积物不同，这可能导致不同的化学分配模式，从而产生不同的毒性效应。通过从三种制定的和五种天然沉积物中得出八种拟除虫菊酯杀虫剂的有机碳和溶解有机碳（K（OC）和 K（DOC））的分配系数，作者描述了制定的和天然沉积物在农药吸附方面的差异。对于所有拟除虫菊酯，制定沉积物的 K（OC）和 K（DOC）的平均值分别比天然沉积物小 2 到 3 倍和 3 到 10 倍。基于统计分析，含有 α-纤维素或马尼托巴泥炭的两种制定沉积物的 K（OC）和 K（DOC）值明显（p<0.0001）小于天然沉积物，而含有新不伦瑞克泥炭的制定沉积物的差异则不显著。K（OC）值与烟炱碳含量密切相关（p<0.001），而羧酸或酚官能团的数量可能影响 K（DOC）。因此，有机物的来源和质量可能是制定沉积物中最重要的因素，必须标准化，以提供沉积物毒性测试的一致性。
