摘要
半透膜采样装置(SPMDs)是一种被动采样装置,它能模拟有机污染物穿过生物膜从水相到生物有机相的分配平衡过程,使得结果能显示出污染物的生物可利用性。它能对环境中有机污染物进行长时间连续监测,所得的是污染物被SPMD富集后的时间权重浓度。本实验测定了温度为18℃时标准SPMD对7种PAHs和3种NPnEO(n=0～2)的静态富集过程,通过测定污染物达到平衡时在SPMD内的浓度和在水相中浓度的比值,求解了各自的SPMD/水分配平衡常数KSPMD。表明了有机污染物在SPMD和水相之间达到分配平衡所需要的时间是随着其Kow值的增高而逐渐增长的,还与其各自的分子极性有关,并且几种达到富集平衡的PAHs在SPMD内的浓度也是随着其Kow值的增高而逐渐变大。比较KSPMD的理论值和实测值可以发现,对于PAHs而言,其实测值都高于理论值,而NPnEO都是实测值低于其理论值。但是KSPMD实测值和理论值随污染物Kow值变化的趋势相同。
Semipermeable membrane device is a kind of passive sampling technique which can mimics the distribution equilibrium process of organic pollutant from water phase to bio-organic phase through the biological membrane, so that the result can indicate the bioavailability of the pollutants. It can be deployed for long periods of time and used to estimate the time-weighted average concentrations of the organic contaminant in water. This study determined the static enrichment process of 7 PAHs and 3 NPnEO （n=0～2） at 18 ℃ by standard SPMDs. Calculation of the KSPMD values of each contaminant by measuring the ratio of concentrations in SPMD and in water during the equilibrium condition was made. The results indicated that the equilibration time of distribution between SPMD and water phase was increased along with the Kow value of different organic compounds. Comparison of the KSPMD values we obtained showed that measured values of PAHs were higher than their theoretical values. And measured values of NPnEO were lower than their theoretical values. However all values of KSPMD showed the same trend with the change of Kow values.
出处
《生态环境》
CSCD
北大核心
2006年第3期475-480,共6页
Ecology and Environmnet
基金
国家自然科学基金委员会
水利部黄河水利委员会黄河研究联合基金重点项目(50239060)
