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[en] Highlights: • Chlorinated paraffins (CPs) were found ubiquitously in tree bark samples. • Wind patterns had little influence on CP profiles in the study region. • Theoretical air concentrations of CPs were used for source apportionment. • CP emissions from the production plant were influential at sites located 6 km away. • A combination of sources influenced the CP profiles at rural and urban-rural sites. Short-chain chlorinated paraffins (SCCPs) and medium-chain chlorinated paraffins (MCCPs) were measured in tree bark samples. These samples were collected around a chemical industrial park containing several chlorinated paraffin (CP) production plants, in a nearby city (Zhengzhou), and along a transect between the industrial park and city. Theoretical air concentrations were back-calculated from concentrations in bark using a predictive equation for estimating equilibrium bark-air partition coefficients. We developed this equation from a series of previously published Kbark-air measurements. Comparison of the normalized concentration profiles along south to north transects showed that wind played only a minor role in CP concentrations and profiles in the region. Three distinct source profiles were found in the complex source region. A fingerprint analysis technique was used to quantify the contribution of each source to the CP burden at various locations along the transect. We found that CP profiles at sites up to 6 km from the industrial park were strongly influenced by CP plant emissions, whereas the sites located in the rural zone and rural-urban interface were influenced by a mixture of CP plant emissions and the neighboring city.
[en] Highlights: • Silica NPs at environmental level induced the negligible embryonic teratogenicity. • Silica NPs at environmental level altered behavioral profiles determined by NBP. • NBP are more sensitive and effective than FET to determine sub-teratogenic toxicity. Larval zebrafish (Danio rerio) is not only an ideal vertebrate applied in Fish Embryos Toxicity (FET) test but also a well-accepted model in behavioral neurotoxicity research. By applying the commercial standard behavioral tracking system (Zebrabox), the locomotion profiles (neurobehavioral-phenomics) of larval zebrafish can be comprehensively monitored and systematically analyzed to probe ecotoxicological neurotoxicity of nano-pollutants at environmental relevant concentration level.
[en] Highlights: • Overall, Euphausia superba had higher metabolic activity than the myctophids. • Lower energy reserves content was found in E. superba. • Antioxidant defenses were, generally, lower in E. superba than in the myctophids. • E. superba had significantly lower mercury (Hg) concentrations than the myctophids. • No relationship was observed between antioxidant defenses and Hg concentrations. Indicators of oxidative stress and metabolic capacity are key factors in understanding the fitness of wild populations. In the present study, these factors were evaluated in the pelagic Southern Ocean taxa Antarctic krill (Euphausia superba) and myctophid fish (Electrona antarctica, Gymnoscopelus braueri and G. nicholsi) to establish a baseline record for future studies. Mercury (Hg) concentrations were also analysed to evaluate its potential impacts on species biochemical performance. E. superba had higher metabolic activity than most of the myctophid species, which may explain the comparatively lower energy reserves found in the former. The activity of antioxidant enzymes showed, generally, a lower level in E. superba than in the myctophid species. The lack of any relationship between Hg concentrations and organisms' antioxidant and biotransformation defence mechanisms indicate that levels of Hg accumulated in the studied species were not high enough to affect their biochemical processes adversely.
[en] Eight Cd-resistant bacteria were isolated from the soil. Based on the resistance and specific growth rate, one isolate from these was chosen. The 16S rRNA (rrs) gene sequence was used to assert this isolate belongs to the genus of Brevibacillus and closely related to Brevibacillus agri (B.agri) DSM 6348T (AB112716). The isolate was termed B.agri C15. The specific growth yields and the Cd-dependent fall in specific growth yield of B.agri C15 was determined under different concentrations of Cd. The current study provides a basis for isolation Cd resistant bacteria with maximum tolerable concentration (MTC) 15 mM Cd from a contaminated soil 490±50 μmolal Cd that could be suitable for a new Cd-bioremediation process; therefore, further studies are needed to investigate this possibility. (paper)
[en] Highlights: • Arsenic burdens were determined in Rhizoprionodon porosus from Brazil. • Sex-dependent hepatic and systemic As transport was observed. • Muscle As concentrations were over the maximum permissible limit set in Brazil. • Calculated THQ indicates risks concerning shark consumption. • The calculated TCR was lower than the threshold for cancer development. Although shark meat is consumed worldwide, elevated arsenic (As) concentrations have been increasingly reported. The Caribbean sharpnose shark (Rhizoprionodon porosus) is a widely consumed fishing resource in Brazil, with scarce information on As burdens to date. Herein, commercial-sized juvenile Caribbean sharpnose sharks from Rio de Janeiro (Brazil) were assessed in this regard, presenting significantly higher hepatic As concentrations in males (8.24 ± 1.20 mg kg-1 wet weight; n = 12) compared to females (6.59 ± 1.87 mg kg-1 w.w.; n = 8), and a positive correlation (r = 0.74) was noted between female muscle and liver As concentrations, indicating systemic inter-tissue transport not evidenced in males. Arsenic concentrations were over the maximum permissible As limit established in Brazilian legislation for seafood and calculated Target Hazard Quotients suggest consumption risks, although cancer risks were not evidenced. Therefore, Public Health concerns with regard to Caribbean sharpnose shark As burdens deserve careful attention.
[en] Highlights: • Five stages of Pb input are divided in the CYSM during 1928–2008. • Aeolian Pb from China’s fossil fuel combustion leads to Pb enrichment in the CYSM. • Atmospheric deposition accounts for 34–43% of the Pb in the CYSM since late 1960s. • Energy consumption and restructuring impact the Pb isotopic ratios. • Pb isotopic ratios may be a potential proxy for the shift of energy consumption. Anthropogenic activities have increased lead (Pb) emissions and impacted their spatiotemporal distributions in coastal seas. To quantify the increasing variability of Pb and identify the specific origins and their corresponding magnitudes, Pb and Pb isotopes are investigated in a well-placed sediment core covering the period of 1928–2008 in the Central Yellow Sea Mud (CYSM). The concentration of Pb varied from 27.17 μg/g to 37.30 μg/g upwardly along the core, with pronounced anthropogenic disturbance since the late 1960s. The Pb input history of the CYSM experienced five stages according to industrialization levels and Pb contamination, with relative pristine stages from 1928 to 1969 and human activity-impacted stages from 1969 to 2008. The 206Pb/207Pb ratio demonstrated an overall decreasing profile while the 208Pb/206Pb ratio displayed the reverse trend upwardly along the core, possibly due to the atmospheric delivery of anthropogenic Pb emissions from northern China. Furthermore, 208Pb/206Pb vs. 206Pb/207Pb shows certain linearity between natural sediment sources and anthropogenic emissions of Pb (atmospheric deposition); thus, atmospheric inputs account for 34–43% of the Pb in the sediment since Pb enrichment using the two-endmember mixing model. Moreover, the steep decrease in 206Pb/207Pb and rapid increase in 208Pb/206Pb since the 1970s suggest the introduction of leaded gasoline and the increasing proportionate consumption of gasoline relative to total energy consumption. The continuously decreasing 206Pb/207Pb ratio and increasing 208Pb/206Pb ratio since 2000 are the combined results of coal consumption, nonferrous smelting, and residual Pb contamination from leaded gasoline, which is quite distinctive from cases in North America and Europe. The relatively high 206Pb/207Pb and low 208Pb/206Pb ratios before 1969 represent the natural Pb isotopic signatures. Hence, Pb input is significantly affected by regional energy consumption and restructuring, and the Pb isotopic ratios may be a potential proxy for the shift in energy consumption.
[en] Highlights: • Microplastic distribution in the North Pacific transition region varies geographically. • Convergence in the nearshore area is a hotspot of floating plastic debris. • Small and transparent film was accumulated in the downstream of the Kuroshio Extension Bifurcation. • The concentration was comparable to that in the Great Pacific Garbage Patch. • Ubiquitous distribution of small and film-shaped plastics in the central Pacific is suggested. Floating plastic debris was investigated in the transition region in the North Pacific between 141°E and 165°W to understand its transportation process from Asian coast to central subtropical Pacific. Distribution was influenced primarily by the current system and the generation process of the high concentration area differed between the western and eastern areas. West of 180°, debris largely accumulated around nearshore convergent area and was transported by eddies and quasi-stationary jet from south to the subarctic region. The average was 15% higher than that previously reported in 1989, suggesting an increase in plastic debris in 30 years. East of 180°, debris concentrated in the calm water downstream of the Kuroshio Extension Bifurcation with considerably high concentration (505,032 ± 991,989 pieces km−2), due to the accumulation of small transparent film caused by calm weather conditions, suggesting a further investigation on small plastic (<1 mm) in the subsurface depth in the subtropical North Pacific.
[en] Highlights: • The study discovers a significant adverse impact of air pollution on both R&D input and output in China. • The empirical analysis is based on a panel data regression model using province-level data for the period 2007—2016. • The scales of annual R&D personnel, expenditures, and new patents all decline, in response to the increase in air pollution. • Air pollution is a considerable threat to innovation and technological progress in China. This study examines the impact of air pollution on research and development (R&D) in China on the basis of province-level data for the period 2007—2016. The study discovers a significant adverse impact of air pollution on both R&D input and output in China. The estimation results in this study are robust to the different indicators used to measure R&D input and output and control for possible endogeneity problems via the instrumental variable approach. According to our estimates, if the concentration of particulate matter with a diameter of 2.5 μm or less (PM2.5) increases by 1%, then the scales of annual R&D personnel, expenditures, and new patents will decline by 0.359%, 0.169%, and 0.293%, respectively. The findings indicate that air pollution is a considerable threat to innovation and technological progress in China.
[en] Few studies have explored the relationship between long-term exposure to particulate matter with an aerodynamic diameter of ≤2.5 μm (PM2.5) and osteoporotic fracture, particularly in high PM2.5 level areas. The aim of this study was to assess the association between long-term exposure to PM2.5 and osteoporotic fracture. We performed a matched case–control study of 16,175 participants obtained from a hospital registry during 2005–2014 in Taiwan. A major osteoporotic fracture was defined as a fracture of the spine, hip, proximal humerus, and forearm. We applied satellite-based spatiotemporal models with 1-km resolution to individually calculate the 1-year average PM2.5 concentration before the index date which was defined as the first visit date for the osteoporotic fracture. Logistic regression models with and without potential confounding factors were used to estimate odds ratios (OR) and 95% confidence intervals (CI) between PM2.5 and osteoporotic fracture, whereas a restricted cubic spline model was used to estimate the dose–response relationship. The sample's median age was 44.7 years (interquartile range: 30.7, 63.1 years). We observed that long-term PM2.5 exposure was associated with osteoporotic fracture, the OR was 1.12 (95% CI: 1.03, 1.22) per 10-μg/m3 increase in PM2.5 in women. In the dose-response association, the OR of osteoporotic fracture was significantly increased for PM2.5 exposures more than 41 μg/m3. We did not find a significant association between PM2.5 (per 10-μg/m3 increase) and osteoporotic fracture among overall population (adjusted OR, 1.02 [95% CI, 0.97 to 1.08]) and men (adjusted OR, 0.94 [95% CI, 0.86 to 1.02]). The results of the stratified analysis showed that women were more sensitive to the adverse impact of PM2.5 that were men, and evidence was obtained of sex-based effect modification (P for interaction = 0.002). Our findings suggest that long-term exposure to PM2.5 is associated with osteoporotic fracture, particularly among women.
[en] Highlights: • Heart rate (HR) could be a good predictor of ventilation (VE). • We derived a novel equation for the relationship between HR and VE in China. • Laboratory VE results strongly correlated with data estimated by the model. • Wide inter-individual variabilities were identified using the regression equations. The health effects of air pollution are associated with the concentration of pollutants and ventilation (VE). VE is difficult to measure directly and has been predicted by heart rate (HR). However, it is unclear whether equations between HR and VE obtained from a laboratory cardiopulmonary exercise test (CPET) can be extended to external groups and there is still a gap in their relationship for a Chinese population.