A low-cost, high throughput bioanalytical screening method was developed for monitoring cis/trans-permethrin in dust and soil samples. The method consisted of a simple sample preparation procedure [sonication with dichloromethane followed by a solvent exchange into methanol:water (1:1)] with bioanalytical detection using a magnetic particle enzyme-linked immunosorbent assay (ELISA). Quantitative recoveries (83–126 %) of cis/trans-permethrin were obtained for spiked soil and dust samples. The percent difference of duplicate ELISA analyses was within ± 20 % for standards and ± 35 % for samples. Similar sample preparation procedures were used for the conventional gas chromatography/mass spectrometry (GC/MS) analysis except that additional cleanup steps were required. Recoveries of cis/trans-permethrin ranged from 81 to 108 % for spiked soil and dust samples by GC/MS. The ELISA-derived permethrin concentrations were highly correlated with the GC/MS-derived sum of cis/trans-permethrin concentrations with a correlation coefficient (r) of 0.986. The ELISA method provided a rapid qualitative screen for cis/trans-permethrin in soil and dust while providing a higher sample throughput with a lower cost as compared to the GC/MS method. The ELISA can be applied as a complementary, low-cost screening tool to prioritize and rank samples prior to instrumental analysis for exposure studies. 相似文献
Human exposure to bioaccessible PCBs via indoor dust is limited around the world. In the present study, the workplace dust sample from commercial office, hospital, secondary school, shopping mall, electronic factory and manufacturing plant were collected from Hong Kong for PCBs analyses. Total PCBs concentrations ranged from 46.8 to 249 ng g−1, with a median of 107 ng g−1. Manufacturing plant showed the highest concentration among all of sampling sites. PCB 77 was found as the dominant congeners. The bioaccessibility of PCBs in small intestinal juice ranging from 8.3% to 26.0% was significantly higher than that in gastric condition, ranging from 4.8% to 12.4%. In addition, significant negative correlations (p < 0.05) were observed between KOW and bioaccessibility for all workplace dust samples. Risk assessment indicated that the averaged daily dose of dioxin-like PCBs via non-dietary intake of workplace dust, considering the bioaccessibility of PCBs, were much lower than the TDI of dioxins (2.3 pg WHO-TEQ kg bw−1 d−1) established by Joint FAO/WHO Expert Committee on Food Additives. 相似文献
A new analytical method using accelerated solvent extraction was developed for the determination of 10 particle-associated polar and semipolar pesticides. In addition, six deuterated analogues of the target compounds were evaluated as internal standards. The method yielded acceptable accuracy (73–103% recovery) and precision (<25% relative standard deviation) for eight compounds. Using size exclusion chromatography (SEC) as cleanup step resulted in higher recoveries compared to solid phase extraction (SPE) cleanup.
Deuterated standards with 10 or more deuterium atoms performed well as internal standards concerning similar recovery and correlation with the target analytes.
The method was employed to extract particle-associated pesticides from 16 streams located in an area with intense agriculture in France. Acetochlor, pirimicarb, tebuconazole, fenpropidin, -endosulfan and chlorfenvinphos were detected at concentrations up to 1 mg kg−1 dry weight. A comparison with aquatic toxicity data indicated potential risk to the benthic fauna exposed to these concentrations of pirimicarb, -endosulfan and chlorfenvinphos.
We suggest that the method presented here be used for the extraction and quantitation of particle-associated polar pesticides. 相似文献