Water Science and Technology Directorate, Environment Canada, Burlington, ON, Canada L7R 4A6.
CASSEN Testing Labs, Toronto, ON, Canada M9W 6H3.
Environ Pollut. 2014 Mar;186:141-8. doi: 10.1016/j.envpol.2013.12.003. Epub 2013 Dec 25.
We examine the concentrations and food web biomagnification of three cyclic volatile methylsiloxanes (cVMS) octamethylcyclotetrasiloxane (D4), decamethylcyclopentasiloxane (D5), and dodecamethylcyclohexasiloxane (D6) using aquatic biota collected from Lake Erie. Concentrations of cVMS in biota were within the range reported for other studies of cVMS in aquatic biota. Trophic magnification factors (TMF) were assessed in various food web configurations to investigate the effects of food web structure. TMF estimates were highly dependent on the inclusion/exclusion of the organisms occupying the highest and lowest trophic levels and were >1 for D4 and D5, indicating biomagnification, in only 1 of the 5 food web configurations investigated and were <1 in the remaining 4 food web configurations. TMF estimates for PCB180 were also dependant on food web configuration, but did not correspond with those obtained for cVMS materials. These differences may be attributed to environmental exposure and/or lipid partitioning differences between PCB180 and cVMS.
我们研究了三种环状挥发性甲基硅氧烷（cVMS）——八甲基环四硅氧烷（D4）、十甲基环五硅氧烷（D5）和十二甲基环己硅氧烷（D6）在安大略湖水生生物中的浓度和食物链生物放大作用。生物体内的 cVMS 浓度处于其他水生生物 cVMS 研究报告的范围内。采用不同的食物网结构评估营养级放大因子（TMF），以研究食物网结构的影响。TMF 估计值高度依赖于占据最高和最低营养级的生物的包含/排除，并且在仅 1 种研究的 5 种食物网结构中，D4 和 D5 的 TMF 估计值大于 1，表明生物放大作用，而在其余 4 种食物网结构中，TMF 估计值小于 1。PCB180 的 TMF 估计值也取决于食物网结构，但与 cVMS 材料的 TMF 估计值不对应。这些差异可能归因于 PCB180 和 cVMS 之间的环境暴露和/或脂质分配差异。
