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Feathers and hair as tools for non-destructive pollution exposure assessment in a mining site of the Iberian Pyrite Belt النص الكامل
2020
Gil-Jiménez, Esperanza | Mateo, Rafael | de Lucas, Manuela | Ferrer, Miguel
Feathers and hair as tools for non-destructive pollution exposure assessment in a mining site of the Iberian Pyrite Belt النص الكامل
2020
Gil-Jiménez, Esperanza | Mateo, Rafael | de Lucas, Manuela | Ferrer, Miguel
Mining is responsible of releasing trace elements to the environment with potential negative effects on wildlife. Traditionally, wildlife exposure assessment has been developed by analyzing mainly environmental compartments or internal tissues. Nowadays, the use of non-destructive matrices such as hair or feathers has increased. Nevertheless, its use in free-living terrestrial mammals or in birds other than raptors or passerines is less frequent. The main objective of our study was to determine the potential for hair and feathers in a rabbit and bird species to be used as non-invasive proxy tissues for assessing internal metal concentrations at polluted sites from mining. We tested whether hair of European rabbit (Oryctolagus cuniculus) and feathers of red-legged partridge (Alectoris rufa) can be used as non-destructive biological monitoring tools of both essential (Cu, Zn) and non-essential (Pb, Cd, As) trace elements in a currently active copper mining site. We found significant different concentrations, particularly in non-essential elements, between reference area and mining site. Non-essential elements Pb and Cd showed higher correlations between tissues and hair/feathers, while few significant patterns were observed for essential elements such as Cu and Zn. Although feathers showed lower levels of correlation with internal tissues than hair, both could be useful as non-destructive biological monitoring tools. Further tissues, and more importantly, hair and feathers allowed discrimination between polluted and reference sites to indicate bioavailability and pollution status. In addition, hair and feathers can be used in monitoring pollution of an active mining site, being specially interesting for biomonitoring a certain period of time in the event of a particular episode of pollution, in addition to the chronic exposure. As occurred with hair in rabbits, feathers seem to be a good compartment to detect differences between a potential polluted area, such the surrounding of an active mine site, and a non-polluted area.
اظهر المزيد [+] اقل [-]Feathers and hair as tools for non-destructive pollution exposure assessment in a mining site of the Iberian Pyrite Belt النص الكامل
2020
Gil-Jiménez, Esperanza | Mateo, Rafael | Lucas, Manuela de | Ferrer, Miguel | Fundación Migres
Mining is responsible of releasing trace elements to the environment with potential negative effects on wildlife. Traditionally, wildlife exposure assessment has been developed by analyzing mainly environmental compartments or internal tissues. Nowadays, the use of non-destructive matrices such as hair or feathers has increased. Nevertheless, its use in free-living terrestrial mammals or in birds other than raptors or passerines is less frequent. The main objective of our study was to determine the potential for hair and feathers in a rabbit and bird species to be used as non-invasive proxy tissues for assessing internal metal concentrations at polluted sites from mining. We tested whether hair of European rabbit (Oryctolagus cuniculus) and feathers of red-legged partridge (Alectoris rufa) can be used as non-destructive biological monitoring tools of both essential (Cu, Zn) and non-essential (Pb, Cd, As) trace elements in a currently active copper mining site. We found significant different concentrations, particularly in non-essential elements, between reference area and mining site. Non-essential elements Pb and Cd showed higher correlations between tissues and hair/feathers, while few significant patterns were observed for essential elements such as Cu and Zn. Although feathers showed lower levels of correlation with internal tissues than hair, both could be useful as non-destructive biological monitoring tools. Further tissues, and more importantly, hair and feathers allowed discrimination between polluted and reference sites to indicate bioavailability and pollution status. In addition, hair and feathers can be used in monitoring pollution of an active mining site, being specially interesting for biomonitoring a certain period of time in the event of a particular episode of pollution, in addition to the chronic exposure. As occurred with hair in rabbits, feathers seem to be a good compartment to detect differences between a potential polluted area, such the surrounding of an active mine site, and a non-polluted area. | This work was supported by funding from Fundación Migres through a collaboration project with Cobre Las Cruces, S.A. We would like to thank technicians from Fundacion Migres for their help during sampling. | Peer reviewed
اظهر المزيد [+] اقل [-]Wastewater treatment plant upgrade induces the receiving river retaining bioavailable nitrogen sources النص الكامل
2020
Wang, Qiaojuan | Liang, Jinsong | Zhao, Chen | Bai, Yaohui | Liu, Ruiping | Liu, Huijuan | Qu, Jiuhui
Currently, wastewater treatment plant (WWTP) upgrades have been implemented in various countries to improve the water quality of the receiving ecosystems and protect aquatic species from potential deleterious effects. The impact of WWTP upgrades on biological communities and functions in receiving waters is a fundamental issue that remains largely unaddressed, especially for microbial communities. Here, we selected two wastewater-dominant rivers in Beijing (China) as study sites, i.e., one river receiving water from an upgraded WWTP to explore the impacts of upgrade on aquatic ecosystems and another river receiving water from a previously upgraded WWTP as a reference. After a five-year investigation, we found that WWTP upgrade significantly decreased total organic nitrogen (N) in the receiving river. As a biological response, N-metabolism-related bacterioplankton are accordingly altered in composition and tend to intensively interact according to the network analysis. Metagenomic analysis based on the N-cycling genes and metagenomic-assembled genomes revealed that WWTP upgrade decreased the abundance of nitrifying bacteria but increased that of denitrifying and dissimilatory nitrate reduction to ammonium (DNRA) bacteria in the receiving river, according to their marker gene abundances. After calculation of the ratios between DNRA and denitrifying bacteria and quantification of genes/bacteria related to ammonium cycling, we deduced the changes in N-metabolism-related bacteria are likely an attempt to provide enough bioavailable N for plankton growth as conservation of ammonium was enhanced in receiving river after WWTP upgrade.
اظهر المزيد [+] اقل [-]Assessing PM2.5 emissions in 2020: The impacts of integrated emission control policies in China النص الكامل
2020
Zhang, Xuguo | Fung, Jimmy C.H. | Zhang, Yumiao | Lau, Alexis K.H. | Leung, Kenneth K.M. | Huang, Wei (Wayne)
Problems with PM₂.₅ pollution in the Pearl River Delta (PRD) have been significantly reduced since the Chinese government released a series of emission control policies including the strengthened controls in the 13ᵗʰ Five-Year Plan. This study assessed the efficacy of emission control measures using the Community Multiscale Air Quality (CMAQ) model to provide data-driven support to government decision making, which is becoming increasingly important. This study aimed to quantitatively evaluate the integrated results of proposed policies for controlling PM₂.₅ concentrations. Accordingly, the regional 2015 emission inventory was modified with recently released government data for the PRD, and scenarios for four dynamical emission-reduction policies (S1–S4) were explored. The results show that all four proposed control measures can help to reduce PM₂.₅ concentrations throughout Hong Kong (HK), Macao, and the PRD economic zone (PRD EZ) by 2020. In all cases, reductions in PM₂.₅ concentrations were larger over PRD EZ than over HK. For HK, the predicted annual concentrations of PM₂.₅ were less than 20 μg/m³ for S1–S3 and less than 15 μg/m³ for S4. For Macao, the predicted annual concentrations of PM₂.₅ were less than 25 μg/m³ for S1 and less than 15 μg/m³ up to S3. Regionally, HK had the lowest PM₂.₅ levels, and the area around Foshan had the highest. Controlling the sources of air pollution (i.e., industry, transport, power production, and other sources) within PRD can get most of the PRD EZ region to below 35 μg/m³. Similar national air quality management efforts could reduce PM₂.₅ levels to less than 25 μg/m³ in the PRD EZ and less than 15 μg/m³ in HK. Control measures in S1 led to significant improvement in Shenzhen and HK, but the S3 option brought the greatest improvement for PRD EZ and Macao. The S4 policy option led to substantial reductions, particularly for HK.
اظهر المزيد [+] اقل [-]Perfluoroalkyl substances (PFASs) in white whales (Delphinapterus leucas) from Svalbard – A comparison of concentrations in plasma sampled 15 years apart النص الكامل
2020
Villanger, Gro D. | Kovacs, Kit M. | Lydersen, Christian | Haug, Line S. | Sabaredzovic, Azemira | Jenssen, Bjørn M. | Routti, Heli
The objective of the present study was to investigate recent concentrations of perfluoroalkyl substances (PFASs) in white whales (Delphinapterus leucas) from Svalbard and compare them to concentrations found in white whales sampled from that same area 15 years ago. Plasma collected from live-captured white whales from two time periods (2013–2014, n = 9, and 1996–2001, n = 11) were analysed for 19 different PFASs. The 11 PFASs detected included seven C₈–C₁₄ perfluoroalkyl carboxylates (PFCAs) and three C₆–C₈ perfluoroalkyl sulfonates (PFSAs) as well as perfluorooctane sulfonamide (FOSA). Recent plasma concentrations (2013–2014) of the dominant PFAS in white whales, perfluorooctane sulfonate (PFOS; geometric mean = 22.8 ng/mL), was close to an order of magnitude lower than reported in polar bears (Ursus maritimus) from Svalbard. PFOS concentrations in white whales were about half the concentrations in harbour (Phoca vitulina) and ringed (Pusa hispida) seals, similar to hooded seals (Cystophora cristata) and higher than in walruses (Odobenus rosmarus) from that same area. From 1996 to 2001 to 2013–2014, plasma concentrations of PFOS decreased by 44%, whereas four C₉₋₁₂ PFCAs and total PFCAs increased by 35–141%. These results follow a similar trend to what has been reported in other studies of Arctic marine mammals from Svalbard. The most dramatic change has been the decline of PFOS concentrations since 2000, corresponding to the production phase-out of PFOS and related compounds in many countries around the year 2000 and a global restriction on these substances in 2009. Still, the continued dominance of PFOS in white whales, and increasing concentration trends for several PFCAs, even though exposure is relatively low, calls for continued monitoring of concentrations of both PFCAs and PFSAs and investigation of biological effects.
اظهر المزيد [+] اقل [-]Three organophosphate flame retardants (OPFRs) reduce sperm quality in Chinese rare minnows (Gobiocypris rarus) النص الكامل
2020
Chen, Rui | Hong, Xiangsheng | Yan, Saihong | Zha, Jinmiao
Organophosphate flame retardants (OPFRs) are widespread in the aquatic environment, but the effects of these chemicals on reproductive toxicity are far from clear. In this study, sperm quality in adult male Chinese rare minnows after exposure to tris-(2-butoxyethyl) phosphate (TBOEP), tris-(1,3-dichloro-2-propyl) phosphate (TDCIPP), and triphenyl phosphate (TPHP) was investigated. No obvious change in sperm concentration and vitality was observed after treatments, whereas significant changes in sperm velocity and morphology were found following all treatments (P < 0.05). Moreover, OPFR exposure significantly increased the apoptosis ratios in testis cells. Analysis of the transcriptomic data revealed that Na⁺/K⁺ ATPase (NKA) related genes were significantly downregulated, and the NKA enzyme activities after all treatments were significantly inhibited (P < 0.05). However, no obvious change in hormone levels in the groups exposed to TBOEP and TDCIPP was observed. These findings indicate that the OPFR-induced reduction of sperm quality might be due to the effects of OPFRs on NKA enzyme instead of changes in hormone levels.
اظهر المزيد [+] اقل [-]Formation and distribution of phenanthrene and its metabolites (monohydroxy-phenanthrenes) in Korean rockfish (Sebastes schlegelii) النص الكامل
2020
Ekpe, Okon Dominic | Kim, Ki-yŏng | Jung, Jee-Hyun | Yim, Un-Hyuk | Oh, Jeong-Eun
This study investigated the tissue distribution of phenanthrene (PHE) and the formation of monohydroxy-phenanthrene (OH-PHE) metabolites in Korean rockfish (Sebastes schlegelii). PHE was intragastrically administered to two groups of rockfish. The first group was exposed to PHE at a low dose (10 mg/kg body weight) and the second group was exposed at a high dose (30 mg/kg body weight). The rockfish were analyzed and the levels of PHE were higher in the liver, followed by muscle, and then bile. PHE concentrations in the liver, muscle, and bile were 1.4–26, 0.10–2.01, and not detected (ND)–0.13 μg/g wet weight, respectively. All five monohydroxylated PHE metabolites (1-OH-PHE, 2-OH-PHE, 3-OH-PHE, 4-OH-PHE, and 9-OH-PHE) were detected only in bile. Among these OH-PHE metabolites, 3-OH-PHE was found at the highest concentration from all fish bile samples in both PHE exposure groups, indicating that regioselective OH-PHE formation occurs in rockfish and 3-OH PHE could be a good biomarker of exposure of Korean rockfish to PHE. Suspect screening analysis of the rockfish bile was performed by LC-QTOF/MS, and the formation of two OH-PHE-DNA adducts (thymine–OH–PHE and cytosine–OH–PHE) were identified in the bile sample collected 6 h after rockfish were exposed to the high PHE dose, indicating that OH-PHE metabolites may be toxic to fish. This is the first report on the formation characteristics of OH-PHE metabolites in rockfish and their use as biomarkers of exposure of rockfish to parent PHE.
اظهر المزيد [+] اقل [-]Projection of ship emissions and their impact on air quality in 2030 in Yangtze River delta, China النص الكامل
2020
Zhao, Junri | Zhang, Yan | Patton, Allison P. | Ma, Weichun | Kan, Haidong | Wu, Libo | Fung, Freda | Wang, Shuxiao | Ding, Dian | Walker, Katherine
China has been in the implementation phase of Domestic Ship Emission Control Areas (DECAs) regulation to reduce emissions of air pollutants from ships near populated areas since 2016. The Yangtze River Delta (YRD) is one of the busiest port clusters in the world, accounting for 11% of global seaborne cargo throughput, so future improvements in shipping emission controls may still be important in this region. To assess the impact of future ship emissions on air quality of coastal areas, this study evaluates emissions reductions and air quality in 2030 for three scenarios (business as usual, stricter regulations, and aspirational policies) representing increasing levels of control compared with a base year of 2015. We projected ship emissions in the region using a bottom-up approach developed in this study and based on the historical ship automatic identification system (AIS) activity data. We then predicted air quality across the YRD region in 2030 using the Community Multiscale Air Quality (CMAQ) model. The annual average contributions of ship emissions to ambient PM₂.₅ would decrease by 70.9%, 80.4%, and 86.2% relative to 2015 under the three scenarios, with the largest reductions of more than 4.1 μg/m³ near Shanghai Port under the aspirational scenario. Reductions in ship emissions generally led to lower levels of PM₂.₅, particularly in most of the coastal cities in the YRD. Compared with a business-as-usual approach the aspirational scenario reduced SO₂, NOₓ and PM₂.₅ concentrations from shipping by 71.8%, 61.1% and 52.5%, respectively. It was also more effective than the stricter regulation scenario, suggesting that the requirement to use 0.1% sulfur fuel within a 100Nm DECA would have additional benefits to ambient PM₂.₅ concentrations beyond 12Nm DECA area. This study provides evidence to inform deliberations on the potential air quality benefits of future control policies for ship emissions in China.
اظهر المزيد [+] اقل [-]Determination of bisphenol A and bisphenol S by a covalent organic framework electrochemical sensor النص الكامل
2020
Pang, Yue-Hong | Huang, Yu-Ying | Wang, Li | Shen, Xiao-Fang | Wang, Yi Ying
Bisphenol A (BPA) is a widely produced chemical that is mainly used as raw material for manufacturing plastic products. It is an endocrine disruptor and causes irreversible damage to the human body. Bisphenol S (BPS), an alternative to BPA, has low dose effects on toxicology and genotoxicity. Herein, we constructed a highly porous crystalline covalent organic framework (COF, CTpPa-2)-modified glassy carbon electrode (GCE) for the electrochemical sensing of BPA and BPS. The electrochemical properties of the CTpPa-2/GCE were characterized using galvanostatic charge-discharge, cyclic voltammetry and differential pulse voltammetry. The CTpPa-2/GCE exhibited remarkable electrocatalytic activity, and the electrochemical responses for BPA and BPS were found to be linear in the concentration ranges of 0.1–50 μM and 0.5–50 μM with detection limits of 0.02 μM and 0.09 μM (S/N = 3), respectively. Moreover, the fabricated sensor was utilized to determine BPA and BPS in bottle samples with recoveries of 87.0%–92.2% and migration rates of 13.2%–28.0%.
اظهر المزيد [+] اقل [-]Indoor exposure to per- and polyfluoroalkyl substances (PFAS) in the childcare environment النص الكامل
2020
Zheng, Guomao | Boor, Brandon E. | Schreder, Erika | Salamova, Amina
Per- and polyfluoroalkyl substances (PFAS) are widely used in stain-resistant carpets, rugs, and upholstery, as well as in waxes and cleaners, and are potential contaminants in the childcare environment. However, limited knowledge exists on the occurrence of PFAS in indoor environments, apart from residential homes. Here, we determined the occurrence and distribution of 37 neutral and ionic PFAS, including perfluoroalkyl carboxylates (PFCAs) perfluoroalkyl sulfonates (PFSAs), fluorotelomer alcohols (FTOHs), fluorotelomer sulfonates (FTSs), perfluorooctane sulfonamides and perfluorooctane sulfonamidoethanols (FOSAs/FOSEs), and fluorotelomer acrylates and fluorotelomer methacrylates (FTACs/FTMACs) in the childcare environment and estimated children’s exposure through dust ingestion and dermal absorption. We analyzed dust and nap mats, a commonly used item in many childcares, from eight facilities located in the United States. Twenty-eight PFAS were detected in dust with total PFAS concentrations (ΣPFAS) ranging from 8.1 to 3,700 ng/g and were dominated by the two neutral PFAS groups: ΣFTOH (n.d. – 3,100 ng/g) and ΣFOSA/FOSE (n.d. – 380 ng/g). The ionic PFAS were detected at lower concentrations and were dominated by 6:2 FTS and 8:2 FTS (median 12 and 5.8 ng/g, respectively). ΣPFAS concentrations in mats (1.6–600 ng/g) were generally an order of magnitude lower than in dust and were dominated by ΣFOSA/FOSE concentrations (n.d. – 220 ng/g). Daily intake of neutral PFAS in the childcare environment via dust ingestion was estimated at 0.20 ng/kg bw/day and accounted for 75% of the ΣPFAS intake. This higher exposure to neutral PFAS is concerning considering that many neutral PFAS are the precursors of toxic ionic PFAS, such as PFOA.
اظهر المزيد [+] اقل [-]Lobsters with pre-existing damage to their mechanosensory statocyst organs do not incur further damage from exposure to seismic air gun signals النص الكامل
2020
Day, Ryan D. | Fitzgibbon, Quinn P. | McCauley, Robert D. | Hartmann, Klaas | Semmens, Jayson M.
Staotcysts, the mechanosensory organs common to many marine invertebrates, have shown sensitivity to aquatic noise. Previously, rock lobsters (Jasus edwardsii) from a remote site with little exposure to anthropogenic noise incurred persistent damage to the statocyst and righting reflex following exposure to seismic air gun signals. Here, J. edwardsii collected from a site subject to high levels of anthropogenic noise were exposed to an equivalent seismic air gun signal regime as the previous study of noise-naïve lobsters. Following exposure, both control and exposed treatments were found to have damage to the statocyst equivalent to that of noise-naïve lobsters following seismic exposure, which led to the conclusion that the damage was pre-existing and not exacerbated by seismic exposure. The source of the damage in the lobsters in this study could not be ascertained, but the soundscape comparisons of the collection sites showed that the noisy site had a 5–10 dB greater level of noise, equivalent to a 3–10 times greater intensity, in the 10–700 Hz range than was found at the remote collection site. In addition to the lack of further damage following seismic exposure, no disruption to the righting reflex was observed. Indeed, compared to the noise naïve lobsters, the lobsters here demonstrated an ability to cope with or adapt to the mechanosensory damage, indicating a need for better understanding of the ecological impacts of the damage caused by low frequency noise on marine organisms. More broadly, this study raises historical exposure to noise as a previously unrecognised but vitally important consideration for studies of aquatic noise.
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