Polychlorinated dibenzo-p-dioxins and dibenzofurans in blood and breast milk samples from residents of a schistosomiasis area with Na-PCP application in China.
ABSTRACT Schistosomiasis has prevailed in some areas of China for a long time. Chinese technical sodium pentachlorophenate (Na-PCP) has been used to control the spread of snail-borne schistosomiasis since the 1960s. Polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs), impurities contained in the Na-PCP, enter the soil and may accumulate in the food chain. In order to evaluate their potentially harmful effects on local residents, 50 breast milk samples and 20 blood samples were collected in 2004 from residents in the Dongting Lake area, one of China's known schistosomiasis areas. Levels of 17 PCDD/F congeners were measured in all samples, and DNA damage was simultaneously assessed in blood samples. The PCDD/F congener distribution patterns in human tissue samples from the Dongting Lake area were similar to those in Na-PCP, and the octachlorodibenzodioxin (OCDD) congener was predominant in all samples. We also had a primary investigation that the breast milk WHO-TEQ associated with some factors such as: age, dietary habit, body mass index (BMI) and the total menses times. In blood samples, the samples with higher OCDD level had higher DDS (DNA damage score) values than those samples with low OCDD level, which indicated that the higher DNA damage value in general population might be caused directly or indirectly by PCDD/Fs. The results also indicated that the WHO-TEQ values in blood were associated with age (r=0.6, p=0.007).
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ABSTRACT: Background Schistosomiasis is the second-most widespread tropical parasitic disease after malaria. Various research strategies and treatment programs for achieving the objective of eradicating schistosomiasis within a decade have been recommended and supported by the World Health Organization. One of these approaches is based on the control of snail vectors in en- demic areas. Previous field studies have shown that competitor or predator introduction can reduce snail numbers, but no systematic investigation has ever been conducted to identify snail microbial pathogens and evaluate their molluscicidal effects. Methodology/Principal findings In populations of Biomphalaria glabrata snails experiencing high mortalities, white nodules were visible on snail bodies. Infectious agents were isolated from such nodules. Only one type of bacteria, identified as a new species of Paenibacillus named Candidatus Paenibacillus glabratella, was found, and was shown to be closely related to P. alvei through 16S and Rpob DNA analysis. Histopathological examination showed extensive bacterial infiltration leading to overall tissue disorganization. Exposure of healthy snails to Paenibacillus-infected snails caused massive mortality. Moreover, eggs laid by infected snails were also infected, decreasing hatching but without apparent effects on spawning. Embryonic lethality was correlated with the presence of pathogenic bacteria in eggs. Conclusions/Significance This is the first account of a novel Paenibacillus strain, Ca. Paenibacillus glabratella, as a snail microbial pathogen. Since this strain affects both adult and embryonic stages and causes significant mortality, it may hold promise as a biocontrol agent to limit schistosomiasis transmission in the field.PLoS neglected tropical diseases 02/2015; 9(2): e0003489(2):1-20. DOI:10.1371/journal.pntd.0003489 · 4.72 Impact Factor
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ABSTRACT: In this paper, flotation in acidic conditions and alkaline leaching soil washing processes were compared to decontaminate four soils with variable contamination with metals, pentachlorophenol (PCP), and polychlorodibenzo dioxins and furans (PCDD/F). The measured concentrations of the four soils prior treatment were between 50 and 250 mg/kg for As, 35 and 220mg/kg for Cr, 80 and 350mg/kg for Cu, and 2.5 and 30mg/kg for PCP. PCDD/F concentrations reached 1394, 1375, 3730, and 6289ng/kg for F1, S1, S2, and S3 soils, respectively. The tests were carried out with masses of 100g of soil (fraction 0-2 mm) in a 2 L beaker or in a 1 L flotation cell. Soil flotation in sulphuric acid for 1 h at 60 degreeC with three flotation cycles using the surfactant cocamidopropyl betaine (BW) at 1% allows the solubilization of metals and PCP with average removal yields of 85%, 51%, 90%, and 62% for As, Cr, Cu, and PCP, respectively. The alkaline leaching for 2 h at 80 degreeC solubilizes As, Cr, Cu, and PCP with average removal yields of 60%, 32%, 77%, and 87%, respectively. Tests on PCDD/F solubilization with different surfactants were carried out in combination with the alkaline leaching process. PCDD/F removal yields of 25%, 72%, 70%, and 74% for F1, S1, S2, and S3 soils, respectively, were obtained using the optimized conditions.Environmental Technology 01/2014; 35(1-4):177-86. DOI:10.1080/09593330.2013.822005 · 1.20 Impact Factor
Article: Dioxin analysis in China[Show abstract] [Hide abstract]
ABSTRACT: The main objective of the Stockholm Convention on Persistent Organic Pollutants (POPs) is to protect human health and the environment from overexposure to POPs. As one of the signatories to the Stockholm Convention, China has built significant capacity and carried out intensive studies on sources of emissions, levels of environmental pollution, and risk assessment associated with dioxins in recent years. Significant progress has been made in adopting and ratifying the Stockholm Convention.This article provides a brief overview of recent progress in capacity building for dioxin analysis, source identification and quantification of dioxin emissions, environmental monitoring of dioxin contamination, and risk assessment of human exposure to dioxins in China.TrAC Trends in Analytical Chemistry 05/2013; 46:178-188. DOI:10.1016/j.trac.2012.05.012 · 6.61 Impact Factor