应用EQC模型评估灭蚁灵和十氯酮的环境归趋

应用EQC模型评估了灭蚁灵和十氯酮在多介质环境中的行为和归趋. 结果表明,在稳定平衡状态下,灭蚁灵和十氯酮在土壤相中的残留率分别达95.6%和94.5%;在稳定非平衡状态下,灭蚁灵除直接排放到大气相、十氯酮除直接排放到水体相中外,还分别约有38%残留在排放相外,它们在大气相和水体相中的浓度水平和质量分布均很低,在沉积物相中则来自于水体相向沉积物相的沉降. 灭蚁灵主要通过大气相的水平迁移以及大气相和土壤相中的化学反应降解输出;十氯酮则主要通过水体相的水平迁移和土壤相的厌氧反应降解输出. 灭蚁灵的主要界面迁移过程是水体相向沉积物相的沉降,其次是沉积物相向水体相的扩散;十氯酮则是大气相向土壤相的迁移,其次是水体相向沉积物相的沉降和大气相向水体相的迁移.      

双柱双ECD检测器-气相色谱法测定水中的灭蚁灵

采用液液萃法取提取水中的灭蚁灵,经浓硫酸净化,用双柱双ECD检测器-气相色谱法进行测定。当取样体积为100ml时,ECD1(色谱柱DB-35ms)和ECD2(色谱柱HP-5)的检出限分别为0.051μg/L和0.038μg/L,六组水样加标回收率为81.6%和78.4%,相对标准偏差3.74%和2.32%。该方法一次进样可得到两组数据来进行灭蚁灵的定性和定量分析,排除了假阳性产生的可能性,因此定性更准确、定量更精确。     

Liver and renal histopathology of North Atlantic long-finned pilot whales (Globicephala melas) contaminated with heavy metals and organochlorine compounds

Long-finned pilot whales (Globicephala melas) from the Faroe Islands are known to be heavily polluted with contaminants, such as mercury (Hg) and organochlorine compounds (OC). This is postulated to exert adverse health effects on whales as well as the human population who rely on its meat and blubber as food sources. It was therefore decided to conduct a screening pilot study to determine contaminant concentrations and histopathology of liver and renal tissues in a total of 14 specimens from this subpopulation. In blubber, the mean ∑OC concentration was 31,887 ng g^?1 lw (range: 18,170–47,425 ng g^?1 lw) of which ∑PCB concentration was 23,416 ng g^?1 lw (range: 13,947–34,543 ng g^?1 lw; n = 3). In liver, mean Hg concentration was 138 µg^?1 ww (range: 54–351 µg g^?1 ww; n = 7) and mean cadmium (Cd) concentration 15 µg g^?1 ww (range: 7–31 µg g^?1 ww; n = 7). In the kidney, the mean Cd concentration was 36 µg g^?1 ww (range: 23–47 µg g^?1 ww; n = 7). Of the liver Hg concentrations, two were at the suggested toxic threshold levels of 60 µg g^?1 ww and five were 2–6-fold above. Liver selenium (Se) : Hg was on average 1.11 (range: 0.97–1.41; n = 7) indicating that Se was in excess, which decreased the risk of acute Hg poisoning. Histopathological examinations showed high prevalence (>35%) of renal glomerular arteriosclerosis, glomerular capillary dilatation, dilatation and hyalinization of Bowman's space/capsule and tubular hyaline casts. In liver tissue, high prevalence was found for portal cell infiltrates, lipid granulomas, hepatocytic lipid accumulation, bile duct proliferation, lipid-filled Ito cells, and focal necrosis. In a single juvenile male, 4 of 8 renal and 3 of 7 liver lesions were present. Cadmium concentrations increased significantly in the presence of glomerular arteriosclerosis and a similar trend was found for tubular hyaline casts. Based on these findings, as well as the nature of the lesions, data indicate that the histopathological changes were a result of age and that contaminants are likely to be the co-factors in the development in at least three renal and four liver lesions.