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Spatial occurrence and composition profile of organophosphate esters (OPEs) in farmland soils from different regions of China: Implications for human exposure
2021
The environmental load of organophosphate ester (OPE) flame retardants has caused a series of problems due to their extensive use. The soil matrix, as an ultimate sink for organic pollution, plays a vital part in the fate of OPEs in the environment. In this study, the spatial occurrence, composition profile and health risk of 13 OPE species in farmland soils from four provinces of China were characterized. Excluding tris(2,3-dibromopropyl) phosphate (TDBPP) and ethylhexyl diphenyl phosphate (EHDPP), the remaining eleven OPEs had a high detection frequency (DF) ranging from 60% to 100%. The range of total OPE (ΣOPE) concentrations were 62.3–394 ng/g dry weight (dw), with a median of 228 ng/g dw. Among these OPEs, tris(2-ethylhexyl) phosphate (TEHP) with a median of 143 ng/g dw) was the predominant species, followed by tricresyl phosphate (TCP; median of 20.1 ng/g dw) and tris(2-chloroethyl) phosphate (TCEP; median of 17.9 ng/g dw). In terms of geographical distribution, significantly lower OPEs levels were found in samples from Heilongjiang (159 ± 47.0 ng/g dw) than in those of Guangxi (264 ± 66.0 ng/g dw), Henan (252 ± 74.5 ng/g dw) and Hubei (242 ± 52.8 ng/g dw) provinces. Principal component analysis and Spearman’s correlations were used to reveal potential sources of OPEs in the different provincial regions. Health risk exposure to OPEs in farmland soils was at an acceptable level (<1.20 × 10⁻⁵ for non-carcinogenic risk to children as the most sensitive age group; and <6.47 × 10⁻¹⁰ for carcinogenic risk to adults as the most sensitive age group) at the present detected concentrations. However, TCEP and TEHP, the predominant risk contributors, should be paid more attention.
Afficher plus [+] Moins [-]Nationwide monitoring of microplastics in bivalves from the coastal environment of Korea
2021
Cho, Youna | Shim, Won Joon | Jang, Mi | Han, Gi Myung | Hong, Sang Hee
Bivalves are useful bioindicators of microplastic contamination in the marine environment for several reasons, such as extensive filter feeding activity, broad geographical distribution, and limited movement capability. This study conducted a nationwide monitoring of microplastic pollution along the Korean coasts using filter-feeding bivalves (including oyster, mussel, and Manila clam) as bioindicators to identify the national contamination level and characteristics of microplastics. Seawater sample was collected from the same sampling stations of oyster and mussel for comparison. Microplastics were widely distributed in both coastal bivalves and waters with mean concentrations of 0.33 ± 0.23 n/g (1.21 ± 0.68 n/individual) in oyster/mussel, 0.43 ± 0.32 n/g (2.19 ± 1.20 n/individual) in Manila clam, and 1400 ± 560 n/m³ in seawater. Despite the lack of significant relationship in the abundance of microplastics, their dominant features such as size, shape, color and polymer type were similar between bivalves and seawater. Fragments (69% for oyster/mussel, 72% for Manila clam, and 77% for seawater), particles smaller than 300 μm (96% for oyster/mussel, 83% for Manila clam, and 84% for seawater) and colorless (79% for oyster/mussel, 85% for Manila clam, 75% for seawater) were the dominant shape, size and color, respectively. The major polymer types were polypropylene, polyethylene, and polyester. The microplastic level in bivalves was relatively high in urbanized areas with a wide diversity of polymer types compared with those in non-urbanized areas, and the proportion of polystyrene in the Korean samples was abundant compared with other regions due to wide use of polystyrene products in Korea. Our result suggests that microplastic contamination is widespread in the Korean coastal environment, and bivalves can reflect the microplastic pollution characteristics of the surrounding waters where they live.
Afficher plus [+] Moins [-]Evaluation of per- and poly-fluorinated alkyl substances (PFAS) in livers of bottlenose dolphins (Tursiops truncatus) found stranded along the northern Adriatic Sea
2021
Sciancalepore, Giuseppe | Pietroluongo, Guido | Centelleghe, Cinzia | Milan, Massimo | Bonato, Marco | Corazzola, Giorgia | Mazzariol, Sandro
Per-and poly-fluorinated alkyl substances (PFAS) are a group of chemicals used in a wide variety of commercial products and industrial applications. These chemicals are persistent, can accumulate in humans' and animals' tissues and in the environment, representing an increasing concern due to their moderate to highly toxicity. Their global distribution, persistence and toxicity led to an urgent need to investigate bioaccumulation also in marine species. In 2013 PFAS contamination was detected in a vast area in Veneto region, mainly in Adige and Brenta rivers. In order to investigate any relevant presence of these substances in marine vertebrates constantly living in the area, PFAS were measured in hepatic tissue samples of 20 bottlenose dolphins (Tursiops truncatus) stranded along the northern Adriatic Sea coastline between 2008 and 2020. Using high performance liquid chromatography-mass spectrometry, 17 target PFAS (PFBA, PFPeA, PFHxA, PFHpA, PFOA, PFNA, PFDA, PFUnA, PFDoA, PFTrDA, PFTeDA, PFBS, PFHxS, PFOS, PFDS, PFHpS, PFPeS), were quantified in the samples. PFAS profiles were generally composed of the same five dominant PFAS (PFOS > PFUnA > PFDA ≈ PFDoA ≈ PFTrDA). The greatest PFOS concentration found was 629,73 ng/g wet weight, and PFOS accounted until 71% in the PFAS profiles. No significant differences between sexes were found, while calves showing higher mean values than adults, possibly indicating an increasing ability in the elimination of PFAS with age. Finally, a temporal analysis was carried out considering three different periods of time, but no temporal differences in concentrations were found. The results suggest that long-chain PFAS are widespread in bottlenose dolphins along the North Adriatic Sea. Furthermore, they represent a baseline to investigate the impact of PFAS on marine mammals’ conservation and health. Filling an important gap in the knowledge of PFAS accumulation in bottlenose dolphins, this study highlights the relevant role of Environmental and Tissue Banks for retrospective analyses on emergent contaminants.
Afficher plus [+] Moins [-]Spatiotemporal variation and distribution characteristics of crop residue burning in China from 2001 to 2018
2021
Yin, Shuai | Guo, Meng | Wang, Xiufeng | Yamamoto, Haruhiko | Ou, Wei
In this study, we integrated a remote-sensing fire product (MOD14A1) and land-use product (MCD12Q1) to extract the number of crop-residue burning (CRB) spots and the fire radiative power (FRP) in China from 2001 to 2018. Moreover, we conducted three trend analyses and two geographic distribution analyses to quantify the interannual variations and summarize the spatial characteristics of CRB on grid (0.25° × 0.25°) and regional scales. The results indicated that CRB presents distinctive seasonal patterns with each sub-region. All trend analyses suggested that the annual number of CRB spots in China increased significantly from 2001 to 2018; the linear trend reached 2615 spots/year, the Theil-Sen slope was slightly lower at 2557 spots/year, and the Mann-Kendal τ was 0.75. By dividing the study period into two sub-periods, we found that the five sub-regions presented different trends in the first and second sub-periods; e.g., the Theil-Sen slope of eastern China in the first sub-period (2001–2009) was 1021 spots/year but was −1599 spots/year in the second period (2010–2018). This suggests that summer CRB has been effectively mitigated in eastern China since 2010. Further, the average FRP of CRB spots presented a decreasing trend from 27.5 MW/spot in 2001 to only 15.8 MW/spot in 2018; this may be attributable to more scattered CRB rather than aggregated CRB. Collectively, the fire spots, FRP, and average FRP indicated that spring, summer, and autumn CRB had dropped dramatically over previous levels by 2018 due to strict mitigation measures by local governments.
Afficher plus [+] Moins [-]Artificial illumination influences niche segregation in bats
2021
Salinas-Ramos, Valeria B | Ancillotto, Leonardo | Cistrone, Luca | Nastasi, Chiara | Bosso, Luciano | Smeraldo, Sonia | Sánchez-Cordero, Víctor | Russo, Danilo
Artificial light at night (ALAN) is a pervasive form of pollution largely affecting wildlife, from individual behaviour to community structure and dynamics. As nocturnal mammals, bats are often adversely affected by ALAN, yet some “light-opportunistic” species exploit it by hunting insects swarming near lights. Here we used two potentially competing pipistrelle species as models, Kuhl’s (Pipistrellus kuhlii) and common (Pipistrellus pipistrellus) pipistrelles, both known to forage in artificially illuminated areas. We set our study in a mountainous area of central Italy, where only recently did the two species become syntopic. We applied spatial modelling and radiotracking to contrast potential vs. actual environmental preferences by the two pipistrelles. Species distribution models and niche analysis showed a large interspecific niche overlap, including a preference for illuminated areas, presenting a potential competition scenario. Pipistrellus pipistrellus association with ALAN, however, was weakened by adding P. kuhlii as a biotic variable to the model. Radiotracking showed that the two species segregated habitats at a small spatial scale and that P. kuhlii used artificially illuminated sites much more frequently than P. pipistrellus, despite both species potentially being streetlamp foragers. We demonstrate that ALAN influences niche segregation between two potentially competing species, confirming its pervasive effects on species and community dynamics, and provide an example of how light pollution and species’ habitat preferences may weave a tapestry of complex ecological interactions.
Afficher plus [+] Moins [-]Phthalate metabolites: Characterization, toxicities, global distribution, and exposure assessment
2021
Zhang, Ying-Jie | Guo, Jia-Liang | Xue, Jing-chuan | Bai, Cui-Lan | Guo, Ying
Phthalates are plasticizers in various products and regarded as endocrine disruptors due to their anti-androgen effects. Environmental occurrence and toxicities of parent phthalates have been widely reported, while the current state of knowledge on their metabolites is rarely summarized. Based on the available literature, the present review mainly aims to 1) characterize the potential metabolites of phthalates (mPAEs) using the pharmacokinetics evidences acquired via animal or human models; 2) examine the molecular and cellular mechanism involved in toxicity for mPAEs; 3) investigate the exposure levels of mPAEs in different human specimens (e.g., urine, blood, seminal fluid, breast milk, amniotic fluid and others) across the globe; 4) discuss the models and related parameters for phthalate exposure assessment. We suggest there is subtle difference in toxic mechanisms for mPAEs compared to their parent phthalates due to their alternative chemical structures. Human monitoring studies performed in Asia, America and Europe have provided the population exposure baseline levels for typical phthalates in different regions. Urine is the preferred matrix than other specimens for phthalate exposure study. Among ten urinary mPAEs, the largest proportions of di-(2-ethylhexyl) phthalate (DEHP) metabolites (40%), monoethyl phthalate (mEP) (43%) and DEHP metabolites/mEP (both 29%) were observed in Asia, America and Europe respectively, and mono-5-carboxy-2-ethypentyl phthalate was the most abundant compounds among DEHP metabolites. Daily intakes of phthalates can be accurately calculated via urinary mPAEs if the proper exposure parameters were determined. Further work should focus on combining epidemiological and biological evidences to establish links between phthalates exposure and biological phenotypes. More accurate molar fractions (FUE) of the urinary excreted monoester related to the ingested diesters should be collected in epidemiological or pharmacokinetic studies for different population.
Afficher plus [+] Moins [-]New global aerosol fine-mode fraction data over land derived from MODIS satellite retrievals
2021
Yan, Xing | Zang, Zhou | Liang, Zhen | Luo, Nana | Ren, Rongmin | Cribb, Maureen | Li, Zhanqing
The space-borne measured fine-mode aerosol optical depth (fAOD) is a gross index of column-integrated anthropogenic particulate pollutants, especially over the populated land. The fAOD is the product of the AOD and the fine-mode fraction (FMF). While there exist numerous global AOD products derived from many different satellite sensors, there have been much fewer, if any, global FMF products with a quality good enough to understand their spatiotemporal variations. This is key to understanding the global distribution and spatiotemporal variations of air pollutants, as well as their impacts on global environmental and climate changes. Modifying our newly developed retrieval algorithm to the latest global-scale Moderate Resolution Imaging Spectroradiometer (MODIS) aerosol product (Collection 6.1), a global 10-year FMF product is generated and analyzed here. We first validate the product through comparisons with the FMF derived from Aerosol Robotic Network (AERONET) measurements. Among our 169,313 samples, the satellite-derived FMFs agreed with the AERONET spectral deconvolution algorithm (SDA)-retrieved FMFs with a root-mean-square error (RMSE) of 0.22. Analyzed using this new product are the global patterns and interannual and seasonal variations of the FMF over land. In general, the FMF is large (>0.80) over Mexico, Myanmar, Laos, southern China, and Africa and less than 0.5 in the Sahelian and Sudanian zones of northern Africa. Seasonally, higher FMF values occur in summer and autumn. The linear trend in the satellite-derived and AERONET FMFs for different countries was explored. The upward trend in the FMFs was particularly strong over Australia since 2008. This study provides a new global view of changes in FMFs using a new satellite product that could help improve our understanding of air pollution around the world.
Afficher plus [+] Moins [-]A new classification approach to enhance future VOCs emission policies: Taking solvent-consuming industry as an example
2021
Zhang, Xinmin | Zhao, Wenjuan | Nie, Lei | Shao, Xia | Dang, Hongyan | Zhang, Weiqi | Wang, Di
Volatile organic compounds (VOCs) has consistently been linked to ozone (O₃) and secondary organic aerosol (SOA) formation, and ongoing emission policies are primarily focusing on total VOCs without addressing the association between regulation measures and secondary pollution characteristic. For enhancing VOCs emission policy, we investigated potential formation of O₃ and SOA based on analyses of node-specific VOCs concentration and species distribution in solvent-consuming industry. Although aromatics were found to contribute most to O₃ and SOA formation averagely (2.57 ± 2.14 g O₃/g VOCs, 1.91 ± 1.67 g SOA/g VOCs), however, large disparity concerning emission and secondary pollution profile were identified among different emission nodes which demonstrated that regulation policy should be formulated based on comprehensive pollution characteristic. Therefore, emission nodes were classified into four clusters through data normalization, formatting and classification process, including aromatics dominated (7 emission nodes), aromatics-alkene dominated (4 emission nodes), aromatics-alcohols dominated (4 emission nodes) and alcohols dominated (4 emission nodes). And different dominating VOCs species were further obtained in each cluster. Subsequently, focusing regulation measures of reducing O₃ and SOA for different emission source clusters were proposed to guide pollution prevention and enhance future VOCs emission policies.
Afficher plus [+] Moins [-]Coral reef health in the Gulf of Honduras in relation to fluvial runoff, hurricanes, and fishing pressure
2021
Kjerfve, Björn | McField, Melanie | Thattai, Deeptha | Giró, Ana
The Gulf of Honduras includes extensive coral reefs in Belize and Guatemala, classified into four biogeographic zones, which are differentially affected by runoff, hurricanes, and fishing. Runoff mostly impacts the coastal and adjacent channel reefs. The Belize Barrier Reef (BBR) experiences less runoff impact due to the prevailing cyclonic ocean circulation. Hurricane waves powerfully impact the BBR, only occasionally the lee-side of Glover's Reef, and rarely the coastal and channel reefs. Fishing pressure is most intense on the coastal and channel reefs, comparatively modest on the BBR, and low at Glover's Reef. The effects of the three local stressors were evaluated using observations from 24 sites in the Gulf of Honduras. Data were analyzed using the Reef Health Index (RHI), with the highest RHI (4.3) for two Glover's Reef sites, medium RHI (2.6) for 10 sites on the barrier reef, and lowest RHI (2.1) for 8 coastal reef sites.
Afficher plus [+] Moins [-]Are non-indigenous species hitchhiking offshore farmed mussels? A biogeographic and functional approach
2021
Piló, D. | Pereira, F. | Carvalho, A.N. | Vasconcelos, P. | Cunha, A.M. | Gaspar, M.B.
The epifauna associated to farmed mussels in southern Portugal coast was analysed, aiming at identifying the species with spreading potential through commercial transport. The presence of a relevant number of the species here found is not reported to at least one of the common mussel export/transposition countries. Indeed, important species biogeographic dissimilarities between the mussel farm area and the Greater North Sea and Western Mediterranean Sea sub-regions were detected, suggesting the potential transport of non-indigenous species (NIS) into other countries. Among them, fouling species such as the anemones Paractinia striata and Urticina felina, the acorn barnacles Balanus glandula and Balanus trigonus or the bryozoans Bugulina stolonifera and Schizoporella errata exhibit functional attributes that allow them to colonise and spread in new areas. This combined biogeographic and functional approach may contribute to clarify the role of aquaculture on the transport of NIS and to predict and prevent their spreading worldwide.
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