MOE Key Laboratory of Pollution Processes and Environmental Criteria, College of Environmental Science and Engineering, Nankai University, Tianjin, 300071, China,
Environ Sci Pollut Res Int. 2014 Feb;21(4):2865-75. doi: 10.1007/s11356-013-2234-4. Epub 2013 Oct 23.
The impact of suspended particles on the bioavailability of pollutants has long been a controversial topic. In this study, adsorption of pentachlorophenol (PCP) onto a natural suspended particulate matter (SPM) and multi-walled carbon nanotubes (MWCNTs) was studied. Facilitated transports of PCP into carp by SPM and MWCNTs were evaluated by bioaccumulation tests exposing carp (Carassius auratus red var.) to PCP-contaminated water in the presence of SPM and MWCNTs, respectively. Desorption of PCP on SPM and MWCNTs in simulated digested fluids was also investigated. The results demonstrate that MWCNTs (K F = 7.99 × 10(4)) had a significantly stronger adsorption capacity for PCP than the SPM (K F = 19.0). The presence of SPM and MWCNTs both improved PCP accumulation in the carp during the 21 days of exposure, and the 21 days PCP concentration in the carp was enhanced by 25.9 and 12.8 % than that without particles, respectively. The enhancement in bioaccumulation by MWCNTs was less than that by the SPM. Considerably more PCP was accumulated in the viscera of the fish (BCF = 519495 for SPM and 148955 for MWCNTs), and the difference in PCP concentrations between different tissues became greater with particles. PCP desorption in the simulated digestive fluids was faster than that in the background solution. Compared to MWCNTs-bound PCP, more SPM-bound PCP was desorbed, and K F of desorption for SPM was at least 4 orders of magnitude higher than that for MWCNTs, which can explain the greater enhancement in bioaccumulation in the presence of SPM. Particle-bound pollutants might pose more risk than pollutants alone.
悬浮颗粒物对污染物生物有效性的影响一直是一个备受争议的话题。在本研究中，研究了五氯苯酚（PCP）在天然悬浮颗粒物（SPM）和多壁碳纳米管（MWCNTs）上的吸附。通过生物积累试验评估了 SPM 和 MWCNTs 将 PCP 促进输送到鲤鱼体内的情况，即在存在 SPM 和 MWCNTs 的情况下，将鲤鱼（Carassius auratus red var.）暴露于受 PCP 污染的水中。还研究了 SPM 和 MWCNTs 上 PCP 的解吸。结果表明，MWCNTs（K F=7.99×10 4）对 PCP 的吸附能力明显强于 SPM（K F=19.0）。在 21 天的暴露期间，SPM 和 MWCNTs 的存在均提高了鲤鱼体内 PCP 的积累，与无颗粒时相比，21 天的 PCP 浓度分别提高了 25.9%和 12.8%。MWCNTs 对生物积累的增强作用小于 SPM。鱼内脏中积累的 PCP 明显更多（SPM 为 519495，MWCNTs 为 148955），并且随着颗粒的存在，不同组织之间的 PCP 浓度差异更大。在模拟消化液中的 PCP 解吸速度比在背景溶液中更快。与 MWCNTs 结合的 PCP 相比，更多的 SPM 结合的 PCP 被解吸，并且 SPM 的解吸 K F 至少比 MWCNTs 高 4 个数量级，这可以解释在 SPM 存在时生物积累的增强程度更大。与单独的污染物相比，颗粒结合的污染物可能会带来更大的风险。
