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Distribution, health risk assessment, and anthropogenic sources of fluoride in farmland soils in phosphate industrial area, southwest China Texte intégral
2019
Wang, Mei | Li, Xiang | He, Wen-yan | Li, Jin-xin | Zhu, Yan-yuan | Liao, Yu-Liang | Yang, Jin-yan | Yang, Xiao-e
The high concentration of fluoride (F) in soils has become a rising concern for its toxicity to microbes, plants, animals and human health. In the present study, the spatial and vertical distribution, health risk assessment and anthropogenic sources of F in farmland soils in an industrial area dominated by phosphate chemical plants were studied. Concentrations of total fluoride (TF) and water soluble fluoride (WSF) in the surface soils decreased with distance within the range of 2500 m at the prevailing downwind of the industrial area. The soil TF and WSF concentrations in 0–40 cm profiles were higher than those in 40–100 cm layers in the industrial area. At the prevailing downwind of the industrial area within 700 m, the hazard quotient values of human exposure to surface soils were higher than 1, indicating that a potential risk may exist for human health in this area. The main exposure pathway for children and adults was oral ingestion and particulate inhalation, respectively. The source apportionment model of soil F was modified based on years’ historical data and experimental data. The results showed that the proportion of anthropogenic sources of soil F was dustfalls (69%) > irrigation water (23%) > air (5%) > chemical fertilizers (3%) in the industrial area. The high F concentration of dustfalls was mainly due to the phosphate rock, phosphogypsum, and surface soils with high F contents from the factories. In order to safeguard human health and alleviate hazards of F to surroundings, the control of pollutants emission from factories was a basic and vital step to reduce F in the soils in industrial areas.
Afficher plus [+] Moins [-]Storage and source of polycyclic aromatic hydrocarbons in sediments downstream of a major coal district in France Texte intégral
2015
Bertrand, O. | Mondamert, L. | Grosbois, C. | Dhivert, E. | Bourrain, X. | Labanowski, J. | Desmet, M.
During the 20th century, the local economy of the Upper Loire Basin (ULB) was essentially based on industrial coal mining extraction. One of the major French coal districts with associated urban/industrial activities and numerous coking/gas plants were developed in the Ondaine-Furan subbasins, two tributaries of the upper Loire main stream. To determine the compositional assemblage, the level and the potential sources of contamination, the historical sedimentary chronicle of the 16 US EPA priority polycyclic aromatic hydrocarbons (PAHs) has been investigated. PAH concentrations were determined using gas chromatography/mass spectrometry (GC/MS) in a dated core, sampled in the Villerest flood-control reservoir located downstream of the Ondaine-Furan corridor (OFC). The most contaminated sediments were deposited prior to 1983 (Σ16PAHs ca. 4429–13,348 ng/g) and during flood events (Σ16PAHs ca. 6380 ng/g – 1996 flood; 5360 ng/g – 2003 flood; 6075 ng/g – 2008 flood), especially in medium and high molecular weight PAHs. Among them, typical pyrogenic PAHs such as FLT, PYR, BbF and BaP were prevalent in most of the core samples. In addition, some PAHs last decade data is available from the Loire Bretagne Water Agency and were analyzed using high-performance liquid chromatography with postcolumn fluorescence derivatization (HPLC/FLD). These results confirm that the most highly contaminated sediments were found downstream of OFC (Σ16PAHs ca. 2264–7460 ng/g). According to the observed molecular distribution, PAHs are originated largely from high-temperature pyrolytic processes. Major sources of pyrogenic PAHs have been emphasized by calculation of specific ratios and by comparison to reported data. Atmospheric deposition of urban and industrial areas, wood combustion and degraded coal tar derived from former factories of coking/gas plants seem to be the major pyrogenic sources. Specifically, particular solid transport conditions that can occur during major flood events lead us to emphasize weathering of former contamination sources, such as more preserved coal tar.
Afficher plus [+] Moins [-]Polychlorinated naphthalenes (PCNs) in riverine and marine sediments of the Laizhou Bay area, North China Texte intégral
2011
Pan, Xiaohui | Tang, Jianhui | Chen, Yingjun | Li, Jun | Zhang, Gan
PCN congeners were analyzed in marine and riverine sediments of the Laizhou Bay area, North China. Concentrations of PCNs ranged from 0.12 to 5.1 ng g⁻ ¹ dry weight (dw) with a mean value of 1.1 ng g⁻ ¹ dw. The levels of PCNs varied largely, with industrial group approximately ten folds higher than those of the rural in riverine sediment. A strong impact by direct discharge from local factories was suggested. Similar compositional profiles were found within groups. High resemblance of compositional profiles between industrial samples and Halowax 1014 was observed. It was indicated that PCNs in riverine sediments were mainly from release of industrial usage, with additional contributions from industrial thermal process at certain sites. In marine sediments, it was suggested that PCNs along the coast of Laizhou Bay were mainly controlled by riverine input. While in the central bay, PCN distributions were possibly impacted by combined multiple factors.
Afficher plus [+] Moins [-]Dietary exposure and risk assessment of exposure to hexabromocyclododecanes in a Taiwan population Texte intégral
2019
Lee, Ching-Chang | Zhang, Weixiang | Chen, Hsiu-Ling
Hexabromocyclododecane (HBCD) is commonly used in commercial products and factories. HBCDs can be detected in the air, bioaccumulated deposits, water, soil, sediments, and in biota and foodstuffs in the food-chain because they are not chemically bound to the polymer. We determined the levels of α-, β-, and γ-HBCDs in 270 foodstuffs and the doses of HBCDs Taiwanese are normally exposed to. We also wanted to create a strategy of risk management for HBCDs based on margins of exposure (MOE). HBCDs were frequently detectible in fish, seafood, and poultry. Their highest concentrations were in fish, oil, poultry, and livestock. The highest estimated daily intake was in 0- to 3-year-olds (1.576 ng/kg/day), and lower in 3- to 6- (1.064 ng/kg/day), 6- to 12- (0.899 ng/kg/day), and lowest in 12- to 16- (0.632 ng/kg/day) year-olds. The exposure doses to HBCDs indicated no health concern for Taiwanese. Except for fish, significant concentrations of α- and γ-HBCDs were detected in many other foodstuffs, which might indicate that exposure to HBCD is a relatively recent problem. Therefore, one goal of a management policy should be to follow-up the flow direction of HBCDs in Taiwan.
Afficher plus [+] Moins [-]Levels and risk assessment of hydrocarbons and organochlorines in aerosols from a North African coastal city (Bizerte, Tunisia) Texte intégral
2018
Barhoumi, Badreddine | Castro-Jiménez, Javier | Guigue, Catherine | Goutx, Madeleine | Sempéré, Richard | Derouiche, Abdelkader | Achour, Amani | Touil, Soufiane | Driss, Mohamed Ridha | Tedetti, Marc
The aim of this study was to assess, for the first time, the concentrations, sources, dry deposition and human health risks of polycyclic aromatic hydrocarbons (PAHs), aliphatic hydrocarbons (AHs), polychlorinated biphenyls (PCBs) and organochlorine pesticides (OCPs) in total suspended particle (TSP) samples collected in Bizerte city, Tunisia (North Africa), during one year (March 2015–January 2016). Concentrations of PAHs, AHs, PCBs and OCPs ranged 0.5–17.8 ng m−3, 6.7–126.5 ng m−3, 0.3–11 pg m−3 and 0.2–3.6 pg m−3, respectively, with higher levels of all contaminants measured in winter. A combined analysis revealed AHs originating from both biogenic and petrogenic sources, while diesel vehicle emissions were identified as dominant sources for PAHs. PCB potential sources included electronic, iron, cement, lubricant factories located within or outside Bizerte city. The dominant OCP congeners were p,p′-DDT and p,p′-DDE, reflecting a current or past use in agriculture. Health risk assessment showed that the lifetime excess cancer risk from exposure to airborne BaP was negligible in Bizerte, except in winter, where a potential risk to the local population may occur.
Afficher plus [+] Moins [-]Short- and medium-chain chlorinated paraffins in sediments from the Laizhou Bay area, North China: Implications for transportation from rivers to marine environment Texte intégral
2018
Pan, Xiaohui | Tang, Jianhui | Tian, Chongguo | Li, Jun | Zhang, Gan
The concentrations of short- and medium-chain chlorinated paraffins (SCCPs and MCCPs) were measured for riverine and marine sediments from the Laizhou Bay area in order to investigate their spatial distributions, possible sources and transport behaviors. Concentrations of SCCPs and MCCPs in riverine sediments varied from 8.4 to 2000 ng g⁻¹ dw and from 1.8 to 3200 ng g⁻¹ dw, respectively. Higher concentrations were found exclusively at industrial sites. Emissions from local factories were the main source of CPs in river sediments of this region. It was 5–22 ng g-1 dw and 6–63 ng g⁻¹ dw with an average value of 11 ng g⁻¹ dw and 9 ng g⁻¹ dw for SCCPs and MCCPs in marine sediments of Laizhou Bay, respectively. In addition to riverine input, ship related emissions are suggested to be another important source of CPs in the Laizhou Bay. MCCPs/SCCPs values and compositional profiles of SCCPs were found to vary along with CP concentrations. A distinct shift to congener groups with shorter carbon chains and lower chlorination from emission sources to remote areas was noticed. The role of log octanol-water partition coefficient (LogKₒw) values indicated decisive in their transportation from emission sources to remote areas in the Laizhou Bay area.
Afficher plus [+] Moins [-]Comparing early twentieth century and present-day atmospheric pollution in SW France: A story of lichens Texte intégral
2013
Agnan, Y. | Séjalon-Delmas, N. | Probst, A.
Lichens have long been known to be good indicators of air quality and atmospheric deposition. Xanthoria parietina was selected to investigate past (sourced from a herbarium) and present-day trace metal pollution in four sites from South-West France (close to Albi). Enrichment factors, relationships between elements and hierarchical classification indicated that the atmosphere was mainly impacted by coal combustion (as shown by As, Pb or Cd contamination) during the early twentieth century, whereas more recently, another mixture of pollutants (e.g. Sb, Sn, Pb and Cu) from local factories and car traffic has emerged. The Rare Earth Elements (REE) and other lithogenic elements indicated a higher dust content in the atmosphere in the early twentieth century and a specific lithological local signature. In addition to long-range atmospheric transport, local urban emissions had a strong impact on trace element contamination registered in lichens, particularly for contemporary data.
Afficher plus [+] Moins [-]Factory employment exposure and human health: Evidence from rural China Texte intégral
2020
Xu, Xiangbo | Sun, Mingxing | Zhang, Linxiu | Fu, Chao | Bai, Yunli | Li, Chang
Quantitating the health effects of employment history in factories, especially polluting ones, is essential for understanding the benefits or losses of industrialization in rural areas. Using a traced subset of nationwide panel data from 2005 covering five provinces, 101 villages, and 2026 households (collected recently in 2016) and the econometric models, this study estimated the effect of factory employment history on workers' health. The results showed that: the absolute number of factory workers increased from 1998 to 2015, and the proportion of factory workers was 7.68% in 2015; the absolute number and the proportion of farmers decreased from 63.84% in 1998 to 29.06% in 2015. Given that all the respondents live in rural areas, the HlthPlace (the first place the individual went to for their last illness in 2015) was selected as the main dependent variable of interest, and Hlthexp (Healthcare expenditure per person at last illness in 2015) and self-reported health were used as auxiliary dependent variables. The findings revealed that, after controlling the characteristics of individual, household, hospital and area, a one year increase of factory employment history corresponded to a 0.035 level increase in the probability of people choosing high-level hospital (p < 0.01) and a 237.61 yuan increase in healthcare expenditure (p < 0.1). The results also showed the adverse effect of self-reported health on factory employment history (p < 0.01). In addition, the relationship between the farming history and health was evaluated, and the econometric results showed that compared with factory employment history, farming history had opposite impacts on health (p < 0.01). Finally, the robustness check showed that the empirical results were reliable and that the initial results were robust. Generally, this study revealed the effect of overall factory employment on health, which is a useful research supplement to the studies on the health effects of specific pollution exposure.
Afficher plus [+] Moins [-]Reduced bioavailability of polycyclic aromatic hydrocarbons (PAHs) in sediments impacted by carbon manufacturing plant effluent: Evaluation by ex situ passive sampling method Texte intégral
2020
Endo, Satoshi | Yoshimura, Mitsuki | Kumata, Hidetoshi | Uchida, Masao | Yabuki, Yoshinori | Nakata, Haruhiko
Potential risks of polycyclic aromatic hydrocarbons (PAHs) in sediments of a Japanese bay contaminated by carbon manufacturing plant effluent were evaluated by calculating toxicity units (TUs). TUs calculated from the measured whole-sediment concentrations (Cwhole) were often higher than or close to 1, signaling a possible toxicity concern to benthic organisms. In contrast, TUs based on the freely dissolved pore water concentrations (Cfree) measured by an ex-situ passive sampling method with polyethylene strips were 0.0007–0.005, much lower than 1, indicating no effect. We also found that the fractions of black carbon in sediments of the contaminated bay were significantly higher than those of reference sites. Overall, we conclude that carbon manufacturing plant effluent substantially increases Cwhole of PAHs in sediments but also increases the fraction of carbonaceous particles that strongly retain PAHs. As a combined result, bioavailable concentrations (as expressed by pore water Cfree) of PAHs do not increase as much as Cwhole. The results of this study indicate that ecotoxicological risks of PAH contamination by carbon manufacturing plants should be evaluated by directly measuring pore water Cfree instead of Cwhole.
Afficher plus [+] Moins [-]Spatial distribution and profile of atmospheric short-chain chlorinated paraffins in the Yangtze River Delta Texte intégral
2020
Niu, Shan | Chen, Ruiwen | Zou, Yun | Dong, Liang | Hai, Reti | Huang, Yeru
Research on the atmospheric occurrence of short chain chlorinated paraffins (SCCPs) in industrialized areas is scarce. In this study, we investigated the concentrations, profile, and spatial distribution of SCCPs in the highly industrialized and developed areas of the Yangtze River Delta (YRD) in China using polyurethane foam passive air samplers. Sampling was performed during two separate periods in 2011. The concentrations of atmospheric SCCPs ranged from 6.1 to 63 ng m⁻³ in summer and 6.2–42 ng m⁻³ in winter. The C₁₀ and C₁₁ groups were the predominant carbon groups in all the samples. Different congener patterns between summer and winter were found, indicating that congeners in the air in winter may be influenced by local and external sources. The highest level of SCCPs was found in Suzhou, which is a highly industrialized area with many manufactories including electronic industries and plastic factories. Higher levels of SCCPs were found in the air than polychlorinated biphenyls (PCBs), organochlorine pesticides (OCPs), and polybrominated diphenyl ether (PBDEs), suggesting that the production and use of SCCPs were much higher than prohibited or restricted persistent organic pollutants (e.g., PCBs, OCPs, and PBDEs). Future studies should investigate the different sources of atmospheric SCCPs by conducting a comprehensive assessment of SCCP exposure.
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