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Monitoring of organochlorine pesticides in blood of women with uterine cervix cancer Full text
2017
Polanco Rodríguez, Ángel G. | Riba López, M Inmaculada | DelValls Casillas, T Ángel | Araujo León, J Alfredo | Mahjoub, Olfa | Prusty, Anjan Kumar
In Yucatan, Mexico, chronic exposure of Mayan population to pesticides is expected as about 30 per cent are drinking polluted water. Residues of organochlorine pesticides (OCP) were monitored in 18 municipalities of Yucatan with high mortality rates due to uterine cervix cancer. 70 blood samples collected from Mayan women living in livestock, agricultural and metropolitan area were analyzed for OCP. Solid Phase Extraction was performed on C18 cartridges and analyzed by Gas Chromatography with Electron Capture Detector. The results showed that the highest OCP levels were detected in blood of women living in the livestock area. OCP detected were endosulfan I (7.35 μg/mL), aldrin (3.69 μg/mL), 4,4′ DDD (2.33 μg/mL), 1.39 and 1.46 μg/mL of δ-HCH. Women from the agricultural area had high concentrations of OCP in their blood, particularly dieldrin (1.19 μg/mL), and 1.26 μg/mL of 4,4′ DDE. In the metropolitan area, 0.080 μg/mL of γ-HCH and 0.064 μg/mL of heptachlore were detected. This monitoring study was also based on epidemiological data of uterine cervical cancer. It was found that environmental factors may have facilitated the infiltration of OCP to the aquifer used for potable water supply. These factors in addition to poverty can have impacts on public health. This first exploratory study suggests that monitoring of OCP in human is important for the establishment of health promotion programs. The integrative analysis of both, environmental and social factors would be helpful to characterize the bioaccumulation of pesticides in humans.
Show more [+] Less [-]Perfluoroalkylated acids in the eggs of great tits (Parus major) near a fluorochemical plant in Flanders, Belgium Full text
2017
Groffen, Thimo | Lopez-Antia, Ana | D'Hollander, Wendy | Prinsen, Els | Eens, Marcel | Bervoets, Lieven
Perfluoroalkyl acids (PFAAs) are highly persistent substances which have been detected in wildlife around the world, including birds. Although bird eggs have often been used to determine and monitor PFAAs levels in the marine environment, this has rarely been done in the terrestrial environment. In the present study we examined the concentrations and composition profile of 12 PFAAs (4 perfluoroalkyl sulfonic acids (PFSAs) and 8 perfluoroalkyl carboxylic acids (PFCAs) in the eggs of great tits (Parus major) collected at a fluorochemical plant and in three other areas, representing a gradient in distance from the pollution source (from 1 to 70 km), in Antwerp, Belgium.The PFSA concentrations measured at the site of the fluorochemical plant were among the highest ever reported in eggs with median concentrations of 10380 ng/g (extrapolated), 99.3 ng/g and 47.7 ng/g for PFOS, PFHxS and PFDS respectively. Furthermore, the median concentration of 19.8 ng/g for PFOA was also among the highest ever reported in bird eggs. Although these concentrations decreased sharply with distance from the fluorochemical plant, levels found in the adjacent sites were still high compared to what has been reported in literature. Moreover, based on what is known in literature, it is likely that these concentrations may cause toxicological effects. PFOS was the dominant contributor to the PFSA and PFAAs (63.4–97.6%) profile at each site, whereas for PFCAs this was PFOA at the plant site and the nearest locations (41.0–52.8%) but PFDoA (37.7%) at the farthest location.Although there is some evidence that PFAAs concentrations close to the plant site are decreasing in comparison with earlier measurements, which may be due to the phase out of PFOS, more research is necessary to understand the extent of the toxicological effects in the vicinity of this PFAAs hotspot.
Show more [+] Less [-]PM2.5-bound metal metabolic distribution and coupled lipid abnormality at different developmental windows Full text
2017
Ku, Tingting | Zhang, Yingying | Ji, Xiaotong | Li, Guangke | Sang, Nan
Atmospheric fine particulate matter (PM2.5) is a serious threat to human health. As a toxicant constituent, metal leads to significant health risks in a population, but exposure to PM2.5-bound metals and their biological impacts are not fully understood. In this study, we determined the metal contents of PM2.5 samples collected from a typical coal-burning city and then investigated the metabolic distributions of six metals (Zn, Pb, Mn, As, Cu, and Cd) following PM2.5 inhalation in mice in different developmental windows. The results indicate that fine particles were mainly deposited in the lung, but PM2.5-bound metals could reach and gather in secondary off-target tissues (the lung, liver, heart and brain) with a developmental window-dependent property. Furthermore, elevations in triglycerides and cholesterol levels in sensitive developmental windows (the young and elderly stages) occurred, and significant associations between metals (Pb, Cd, Mn, and As) and cholesterol in the heart, brain and liver were observed. These findings suggest that PM2.5 inhalation caused selective metal metabolic distribution in tissues with a developmental window-dependent property and that the effects were associated with lipid alterations. This provides a foundation for the underlying systemic toxicity following PM2.5 exposure based on metal components.
Show more [+] Less [-]Slaughterhouse wastewater treatment using an advanced oxidation process: Optimization study Full text
2017
Davarnejad, Reza | Nasiri, Samaneh
In this paper, a poultry slaughterhouse wastewater (PSW) was treated in terms of chemical oxygen demand (COD) and color reduction using electro-Fenton (EF) technique under response surface methodology (RSM). The effects of five significant independent variables such as reaction time, pH, H2O2/Fe2+ molar ratio, current density, volume ratio of H2O2/PSW (ml/l) were investigated on the COD and color removal. Experimental data were optimized by Box-Behnken design (BBD) and RSM. The optimum conditions were experimentally found at pH of 4.38, reaction time of 55.60 min, H2O2/Fe2+ molar ratio of 3.73, current density of 74.07 mA/cm2, volume ratio of H2O2/PSW of 1.63 ml/l for 92.37%COD removal and at pH of 3.39, reaction time of 49.22 min, H2O2/Fe2+ molar ratio of 3.62, current density of 67.90 mA/cm2, volume ratio of H2O2/PSW of 1.44 ml/l for 88.06% color removal.
Show more [+] Less [-]Herbicide and insect resistant Bt cotton pollen assessment finds no detrimental effects on adult honey bees Full text
2017
Niu, Lin | Ma, Weihua | Lei, Chaoliang | Jurat-Fuentes, Juan Luis | Chen, Lizhen
One important concern regarding the use of transgenic cotton expressing insecticidal toxins from the bacterium Bacillus thuringiensis (Bt) is its potential detrimental effect on non-target organisms. The honey bee (Apis mellifera) is the most important pollinator species worldwide and it is directly exposed to transgenic crops by the consumption of genetically modified (GM) pollen. However, the potential effects of Bt cotton on A. mellifera remain unclear. In the present study, we assessed the effects of two Bt cotton varieties; ZMSJ expressing the Cry1Ac and Cry2Ab insecticidal proteins, and ZMKCKC producing Cry1Ac and EPSPS, on A. mellifera. Feeding on pollen from two Bt cotton varieties led to detection of low levels of Cry toxins (<10 ng/g fresh weight) in the midgut of A. mellifera adults, yet expression of detoxification genes did not change significantly compared to feeding on non-Bt cotton. Binding assays showed no Cry1Ac or Cry2Ab binding to midgut brush border membrane proteins from A. mellifera adults. Taken together, these results support minimal risk for potential negative effects on A. mellifera by exposure to Bt cotton.
Show more [+] Less [-]Impact of osmoregulation on the differences in Cd accumulation between two contrasting edible amaranth cultivars grown on Cd-polluted saline soils Full text
2017
Xu, Zhi-Min | Li, Qu-Sheng | Yang, Ping | Ye, Han-Jie | Chen, Zi-Shuo | Guo, Shi-Hong | Wang, Lili | He, Bao-Yan | Zeng, E. Y. (Eddy Y.)
This study aimed to investigate the difference of osmoregulation between two edible amaranth cultivars, Liuye (high Cd accumulator) and Quanhong (low Cd accumulator), under salinity stress and determine the effects of such difference on Cd accumulation. A pot experiment was conducted to expose the plants to sewage-irrigated garden soil (mean 2.28 mg kg⁻¹ Cd) pretreated at three salinity levels. Under salinity stress, the concentrations of Cd in the two cultivars were significantly elevated compared with those in the controls, and the Cd concentration in Liuye was statistically higher than that in Quanhong (p < 0.05). Salinity-induced osmoregulation triggered different biogeochemical processes involved in Cd mobilization in the rhizosphere soil, Cd absorption, and translocation by the two cultivars. Rhizosphere acidification induced by an imbalance of cation over anion uptake was more serious in Liuye than in Quanhong, which obviously increased soil Cd bioavailability. Salinity-induced injuries in the cell wall pectin and membrane structure were worse in Liuye than in Quanhong, increasing the risk of Cd entering the protoplasts. The chelation of more cytoplasmic Cd²⁺ with Cl⁻ ions in the roots of Liuye promoted Cd translocation into the shoots. Furthermore, the less organic solutes in the root sap of Liuye than in that of Quanhong also favored Cd translocation into the shoots. Hence, osmoregulation processes can be regarded as important factors in reducing Cd accumulation in crop cultivars grown on saline soils.
Show more [+] Less [-]Exposure to environmental noise and risk for male infertility: A population-based cohort study Full text
2017
Min, Kyoung-Bok | Min, Chin-yŏng
Noise is associated with poor reproductive health. A number of animal studies have suggested the possible effects of exposure to high noise levels on fertility; to date, a little such research has been performed on humans.We examined an association between daytime and nocturnal noise exposures over four years (2002–2005) and subsequent male infertility.We used the National Health Insurance Service-National Sample Cohort (2002–2013), a population-wide health insurance claims dataset. A total of 206,492 males of reproductive age (20–59 years) with no history of congenital malformations were followed up for an 8-year period (2006–2013). Male infertility was defined as per ICD-10 code N46. Data on noise exposure was obtained from the National Noise Information System. Exposure levels of daytime and night time noise were extrapolated using geographic information systems and collated with the subjects' administrative district code, and individual exposure levels assigned.During the study period, 3293 (1.6%) had a diagnosis of infertility. Although there was no association of infertility with 1-dB increments in noise exposure, a non-linear dose-response relationship was observed between infertility and quartiles of daytime and night time noise after adjustment for confounding variables (i.e., age, income, residential area, exercise, smoking, alcohol drinking, blood sugar, body mass index, medical histories, and particulate pollution). Based on WHO criteria, adjusted odds for infertility were significantly increased (OR = 1.14; 95% CI, 1.05–1.23) in males exposed to night time noise ≥ 55 dB.We found a significant association between exposure to environmental noise for four years and the subsequent incidence of male infertility, suggesting long-term exposure to noise has a role in pathogenesis of male infertility.
Show more [+] Less [-]Toxicity of vanadium in soil on soybean at different growth stages Full text
2017
Yang, Jinyan | Wang, Mei | Jia, Yanbo | Gou, Min | Zeyer, Josef
Vanadium(V) is present in trace amounts in most plants and widely distributed in soils. However, the environmental toxicity of V compound in soils is controversial. A greenhouse study with soybean from germination to bean production under exposure to pentavalent V [V(V)] was conducted to elucidate the interaction of plants and V fractions in soils and to evaluate the toxicity of V at different plant growth stages. Soybean growth has no effect on non-specific-bond and specific-bond fractions of V in soils, but V fractionation occurred in more extraction-resistant phases at high V concentrations. High concentrations of V(V) postponed the germination and growth of the soybeans. Bean production was less than half of that of the control at 500 mg kg⁻¹ spiked V(V). For the 0 mg kg⁻¹ spiked V(V) treated plants, the root was not the main location where V was retained. Vanadium in the soils at ≤ 250 mg kg⁻¹ did not significantly affect the V concentration in the shoot and leaf of soybeans. With the increase in V concentration in soil, V concentrations in roots increased, whereas those in beans and pods decreased. From vegetative growth to the reproductive growth, the soybeans adsorbed more V and accumulated more V in the roots, with <20% transported to the aboveground parts. Hence, the analysis of V concentration in vegetative tissues or beans may not be a useful indicator for V pollution in soil. Meanwhile, the ratio of V concentration in cell wall to the total V concentration in the root increased with the increase in V(V) concentration in soils. Our results revealed that high concentrations of V inhibited soybean germination and biomass production. However, plants may produce self-defense systems to endure V toxicity.
Show more [+] Less [-]Aerosol characteristics and sources in Yangzhou, China resolved by offline aerosol mass spectrometry and other techniques Full text
2017
Ge, Xinlei | Li, Ling | Chen, Yanfang | Chen, Hui | Wu, Dan | Wang, Junfeng | Xie, Xinchun | Ge, Shun | Ye, Zhaolian | Xu, Jianzhong | Chen, Mindong
Detailed chemical characterization of fine aerosols (PM2.5) is important for reducing air pollution in densely populated areas, such as the Yangtze River Delta region in China. This study systematically analyzed PM2.5 samples collected during November 2015 to April 2016 in urban Yangzhou using a suite of techniques, in particular, an Aerodyne soot particle aerosol mass spectrometry (SP-AMS). The techniques used here reconstructed the majority of total PM2.5 measured where extracted species comprised on average 91.2%. Source analyses of inorganic components showed that secondary nitrate, sulfate and chloride were the major species, while primary sources including biomass burning, coal combustion, traffic, industry and re-suspended dust due to nearby demolition activities, could contribute to other species. EC-tracer method estimated that the organic matter (OM) was composed of 65.4% secondary OM (SOM) and 34.6% primary OM (POM), while the SP-AMS analyses showed that the OM was comprised of 60.3% water-soluble OM (WSOM) and 39.7% water-insoluble OM (WIOM). Correlation analyses suggested that WSOM might be rich in secondary organic species, while WIOM was likely mainly comprised of primary organic species. We further conducted positive matrix factorization (PMF) analyses on the WSOM, and identified three primary factors including traffic, cooking and biomass burning, and two secondary factors. We found the secondary factors dominated WSOM mass (68.1%), and their mass contributions increased with the increase of WSOM concentrations. Relatively small contribution of primary sources to WSOM was probably due to their low water solubility, which should be investigated further in future. Overall, our findings improve understanding of the complex aerosol sources and chemistry in this region.
Show more [+] Less [-]Quantification of the overall measurement uncertainty associated with the passive moss biomonitoring technique: Sample collection and processing Full text
2017
Aboal, J.R. | Boquete, M.T. | Carballeira, A. | Casanova, A. | Debén, S. | Fernández, J.A.
In this study we examined 6080 data gathered by our research group during more than 20 years of research on the moss biomonitoring technique, in order to quantify the variability generated by different aspects of the protocol and to calculate the overall measurement uncertainty associated with the technique. The median variance of the concentrations of different pollutants measured in moss tissues attributed to the different methodological aspects was high, reaching values of 2851 (ng·g⁻¹)² for Cd (sample treatment), 35.1 (μg·g⁻¹)² for Cu (sample treatment), 861.7 (ng·g⁻¹)² and for Hg (material selection). These variances correspond to standard deviations that constitute 67, 126 and 59% the regional background levels of these elements in the study region. The overall measurement uncertainty associated with the worst experimental protocol (5 subsamples, refrigerated, washed, 5 × 5 m size of the sampling area and once a year sampling) was between 2 and 6 times higher than that associated with the optimal protocol (30 subsamples, dried, unwashed, 20 × 20 m size of the sampling area and once a week sampling), and between 1.5 and 7 times higher than that associated with the standardized protocol (30 subsamples and once a year sampling). The overall measurement uncertainty associated with the standardized protocol could generate variations of between 14 and 47% in the regional background levels of Cd, Cu, Hg, Pb and Zn in the study area and much higher levels of variation in polluted sampling sites. We demonstrated that although the overall measurement uncertainty of the technique is still high, it can be reduced by using already well defined aspects of the protocol. Further standardization of the protocol together with application of the information on the overall measurement uncertainty would improve the reliability and comparability of the results of different biomonitoring studies, thus extending use of the technique beyond the context of scientific research.
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