No abstract

Aflatoxin M1 (AFM1 ) is a main cause of hepatocarcenogenoma in Chinese population. Measurement of aflatoxin exposure in human may help in providing clear evidence for the exposure of specific environmental pollutants in certain population. "One child policy" in China offered parents more careful to choose safe food during pregnancy, but no reports published on the efficacy of their endeavor. In present study, we aimed to assess the exposure of AFM1 in Chinese pregnant women. The urine samples were collected from 600 volunteers from Zhejiang province, China and the urinary concentration of AFM1 was measured using ELISA kit. AFM1 was detected in 84% of the pregnant women. The geometric mean and 95th percentile concentration of AFM1 in pregnant women were 50.3 ng/L and 633.5 ng/L, respectively. Our results point out that pregnant women especially are at the high risk of exposure to AFM1 . Our results also indicate that although "one child policy" offered parents to pay more attention for the selection of safe food, but detection of AFM1 in urine of pregnant women indicate that more foods containing AFM1 still need to be detected. Highest exposure of AFM1 in pregnant women indicates that awareness campaigns must be started especially in the rural areas of China regarding the possible hazardous effects of AFM1 exposure in pregnant women.

No abstract

Bisphenol A (BPA) is widely used to manufacture polycarbonate plastics and epoxy resins, which are in widespread use in China. Concerns about potential health impacts from exposure to BPA among the general population are increasing day by day. A sensitive and specific antibody was prepared to develop and compare direct and indirect competitive enzyme-linked immunosorbent assays (ELISAs) for the determination of BPA in human urine. The IC 50 value and limit of detection (LOD) for the direct competitive ELISA were 5.5 ng mL À1 and 0.03 ng mL À1 respectively whereas, for the indirect competitive ELISA, the IC 50 value and LOD were 7.0 ng mL À1 and 0.08 ng mL À1 , respectively. We found that the direct competitive ELISA was more specific and sensitive than the indirect competitive ELISA. The established immunoassays were also applied in the determination of BPA in human urine samples. The results from fortified samples and real samples indicated that the direct competitive ELISA was more sensitive and reliable for the measurement of BPA in human urine as compared to the indirect competitive ELISA. Materials and methods Chemicals and reagentsBPA, 4,4-bis (4-hydroxyphenyl) valeric acid (BHPVA), N-hydroxysuccinimide (NHS), 1-ethyl-3-(3-dimethyllaminopropyl) carbodiimide hydrochloride (EDC) and horseradish peroxidase (HRP)

We simultaneously set up two competitive (direct and indirect) enzyme-linked immunosorbent assays (ELISAs) based on the same antibody for estimation of cotinine (COT) in pregnant women especially and population generally exposed to environmental tobacco smoke. The results show that the limits of detection (LODs) for direct competitive ELISA and indirect competitive ELISA were 0.04 μgL(-1) and 0.1 μgL(-1), respectively. Direct competitive ELISA was found to be more sensitive than indirect competitive ELISA. Thereafter, we applied our direct competitive ELISA for the detection of COT from urinary samples taken from 450 volunteers from the Zhejiang Province of China. COT was detected in 100% of participants with concentration ranging from LOD to 5358.0 μgL(-1). The GM and 95th percentile concentration of COT in pregnant women were 6.3 μgL(-1) and 57.2 μgL(-1), respectively. Males had statistically higher COT concentrations than females (P < 0.0001), active smokers had statistically higher COT concentrations than non-smokers (P < 0.0001), whereas, non-pregnant women were found to have higher COT concentration than pregnant women. We conclude that our developed direct competitive ELISA is useful for detecting the COT in urinary concentration of human. The human urinary data obtained in this study indicated that common people generally and pregnant women especially were highly exposed to COT. Further studies are needed to focus on the sources of exposure, potential health effects and risk assessment of exposure to COT.