Plastic pollution is a major global concern with several million microplastic particles entering every day freshwater ecosystems via wastewater discharge. Microplastic particles stimulate biofilm formation (plastisphere) throughout the water column and have the potential to affect microbial community structure if they accumulate in pelagic waters, especially enhancing the proliferation of biohazardous bacteria. To test this scenario, we simulated the inflow of treated wastewater into a temperate lake using a continuous culture system with a gradient of concentration of microplastic particles. We followed the effect of microplastics on the microbial community structure and on the occurrence of integrase 1 (int1), a marker associated with mobile genetic elements known as a proxy for anthropogenic effects on the spread of antimicrobial resistance genes. The abundance of int1 increased in the plastisphere with increasing microplastic particle concentration, but not in the water surrounding the microplastic particles. Likewise, the microbial community on microplastic was more similar to the original wastewater community with increasing microplastic concentrations. Our results show that microplastic particles indeed promote persistence of typical indicators of microbial anthropogenic pollution in natural waters, and substantiate that their removal from treated wastewater should be prioritised.

The occurrence of five groups of semivolatile organic compounds (SVOCs) (total of ∼120 distinct chemicals) was investigated in senior care facilities in the United States and in Portugal. Indoor settled dust samples were collected from fourteen facilities, and the concentrations of organophosphate esters (OPEs), brominated flame retardants (BFRs), polycyclic aromatic hydrocarbons (PAHs), organochlorine pesticides (OCPs), and polychlorinated biphenyls (PCBs) were measured in these samples. Overall, OPEs, PAHs, and BFRs were the most abundant, and OCPs and PCBs were the least abundant SVOC groups in dust collected from both U.S. and Portuguese facilities. ∑OPE, ∑PAH, and ∑BFR concentrations were significantly higher in U.S. facilities than those in Portuguese facilities (P < 0.001), while ∑OCP and ∑PCB concentrations were not different between the two countries (P < 0.05). The samples were collected from three different microenvironments, including bedrooms, living rooms, and corridors. ∑OPE, ∑PAH, and ∑BFR concentrations were up to five times higher in corridors compared to bedrooms and living rooms. ∑OCP and ∑PCB concentrations were overall higher in bedrooms and in living rooms and lower in corridors.

Breast cancer is the most frequent tumor in women worldwide, although well-established risk factors account for 53%–55% of cases. Therefore, other risk factors, including environmental exposures, may explain the remaining variation. Our objective was to assess the relationship between risk of breast cancer and residential proximity to industries, according to categories of industrial groups and specific pollutants released, in the context of a population-based multicase-control study of incident cancer carried out in Spain (MCC-Spain). Using the current residence of cases and controls, this study was restricted to small administrative divisions, including both breast cancer cases (452) and controls (1511) in the 10 geographical areas recruiting breast cancer cases. Distances were calculated from the respective woman's residences to the 116 industries located in the study area. We used logistic regression to estimate odds ratios (ORs) and 95% confidence intervals (95%CIs) for categories of distance (between 1 km and 3 km) to industrial plants, adjusting for matching variables and other confounders. Excess risk (OR; 95%CI) of breast cancer was found near industries overall (1.30; 1.00–1.69 at 3 km), particularly organic chemical industry (2.12; 1.20–3.76 at 2.5 km), food/beverage sector (1.87; 1.26–2.78 at 3 km), ceramic (4.71; 1.62–13.66 at 1.5 km), surface treatment with organic solvents (2.00; 1.23–3.24 at 3 km), and surface treatment of plastic and metals (1.51; 1.06–2.14 at 3 km). By pollutants, the excess risk (OR; 95%CI) was detected near industries releasing pesticides (2.09; 1.14–3.82 at 2 km), and dichloromethane (2.09; 1.28–3.40 at 3 km). Our results suggest a possible increased risk of breast cancer in women living near specific industrial plants and support the need for more detailed exposure assessment of certain agents released by these plants.

The temporal and spatial trends in sediment of 22 poly- and perfluorinated (PFAS) compounds were investigated in the southern Great Lakes Erie and Ontario as well as Lake St. Clair. Surface concentrations measured by Ponar grab samples indicated a trend for greater concentrations near to urban sites. Mean concentrations ∑22PFAS were 15.6, 18.2 and 19 ng g−1 dm for Lakes St. Clair, Erie and Ontario, respectively. Perfluoro-n-butanoic acid (PFBA) and Perfluoro-n-hexanoic acid (PFHxA) were frequently determined in surface sediment and upper core samples indicating a shift in use patterns. Where PFBA was identified it was at relatively great concentrations typically >10 ng g−1 dm. However as PFBA and PFHxA are less likely to bind to sediment they may be indicative of pore water concentrations Sedimentation rates between Lake Erie and Lake Ontario differ greatly with greater rates observed in Lake Erie. In Lake Ontario, in general concentrations of PFAS observed in core samples closely follow the increase in use along with an observable change due to regulation implementation in the 1970s for water protection. However some of the more water soluble PFAS were observed in deeper core layers than the time of production could account for, indicating potential diffusion within the sediment. Given the greater sedimentation rates in Lake Erie, it was hoped to observe in greater resolution changes since the mid-1990s. However, though some decrease was observed at some locations the results are not clear. Many cores in Lake Erie had clearly observable gas voids, indicative of gas ebullition activity due to biogenic production, there were also observable mussel beds that could indicate mixing by bioturbation of core layers.

Ecological effects of atmospheric nitrogen (N) and sulfur (S) deposition on two hardwood forest sites in the eastern United States were simulated in the context of a changing climate using the dynamic coupled biogeochemical/ecological model chain ForSAFE-Veg. The sites are a mixed oak forest in Shenandoah National Park, Virginia (Piney River) and a mixed oak-sugar maple forest in Great Smoky Mountains National Park, Tennessee (Cosby Creek). The sites have received relatively high levels of both S and N deposition and the climate has warmed over the past half century or longer. The model was used to evaluate the composition of the understory plant communities, the alignment between plant species niche preferences and ambient conditions, and estimate changes in relative species abundances as reflected by plant cover under various scenarios of future atmospheric N and S deposition and climate change. The main driver of ecological effects was soil solution N concentration. Results of this research suggested that future climate change might compromise the capacity for the forests to sustain habitat suitability. However, vegetation results should be considered preliminary until further model validation can be performed. With expected future climate change, preliminary estimates suggest that sustained future N deposition above 7.4 and 5.0 kg N/ha/yr is expected to decrease contemporary habitat suitability for indicator plant species located at Piney River and Cosby Creek, respectively.

Even though the Amazon region is widely studied, there is still a gap regarding Cr exposure and its risk to human health. The objectives of this study were to 1) determine Cr concentrations in seven chemical fractions and 6 particle sizes in Amazon soils, 2) quantify hexavalent Cr (CrVI) concentrations using an alkaline extraction, 3) determine the oral and lung bioaccessible Cr, and 4) assess Cr exposure risks based on total and bioaccessible Cr in soils. The total Cr in both A (0–20 cm) and B (80–100 cm) horizons was high at 2346 and 1864 mg kg⁻¹. However, sequential extraction indicated that available Cr fraction was low compared to total Cr, with Cr in the residual fraction being the highest (74–76%). There was little difference in total Cr concentrations among particle sizes. Hexavalent Cr concentration was also low, averaging 0.72 and 2.05 mg kg⁻¹ in A and B horizon. In addition, both gastrointestinal (21–22 mg kg⁻¹) and lung (0.95–1.25 mg kg⁻¹) bioaccessible Cr were low (<1.2%). The low bioavailability of soil Cr and its uniform distribution in different particle sizes indicated that Cr was probably of geogenic origin. Exposure based on total Cr resulted in daily intake > the oral reference dose for children, but not when using CrVI or bioaccessible Cr. The data indicated that it is important to consider both Cr speciation and bioaccessibility when evaluating risk from Cr in Amazon soils.

Studies have showed the increasing environmental and public health risks of toxic emissions from natural gas and oil mining, which have become even worse as fracking is becoming a dominant approach in current natural gas extraction. However, governments and communities often overlook the serious air pollutants from oil and gas mining, which are often quantified lower than the significant levels of adverse health effects. Therefore, we are facing a challenging dilemma: how could we clearly understand the potential risks of air toxics from natural gas and oil mining.This short study aims at the design and application of simple and robust methods to enhance and improve current understanding of the becoming worse toxic air emissions from natural gas and oil mining as fracking is becoming the major approach. Two simple ratios, the min-to-national-average and the max-to-national-average, are designed and applied to each type of air pollutants in a natural gas and oil mining region. The two ratios directly indicate how significantly high a type of air pollutant could be due to natural gas and oil mining by comparing it to the national average records, although it may not reach the significant risks of adverse health effects according to current risk screening methods. The min-to-national-average and the max-to-national-average ratios can be used as a direct and powerful method to describe the significance of air pollution by comparing it to the national average. The two ratios are easy to use for governments, stakeholders, and the public to pay enough attention on the air pollutants from natural gas and oil mining. The two ratios can also be thematically mapped at sampled sites for spatial monitoring, but spatial mitigation and analysis of environmental and health risks need other measurements of environmental and demographic characteristics across a natural gas and oil mining area.

A long-lasting high particulate matter (PM) concentration episode persisted over East Asia from May 24 to June 3, 2014. The Nested Air Quality Prediction Model System (NAQPMS) was used to investigate the mixing of dust and anthropogenic pollutants during this episode. Comparison of observations revealed that the NAQPMS successfully reproduced the time series PM₂.₅ and PM₁₀ concentrations, as well as the nitrate and sulfate concentrations in fine (aerodynamic diameter ≤ 2.5 μm) and coarse mode (2.5 μm < aerodynamic diameter ≤ 10 μm). This episode originated from two dust events that occurred in the inland desert areas of Mongolia and China, and then the long-range transported dust and anthropogenic pollutants were trapped over the downwind region of East Asia for more than one week due to the blocked north Pacific subtropical high-pressure system over the east of Japan. The model results showed that mineral dust accounted for 53–83% of PM₁₀, and 39–67% of PM₂.₅ over five cities in East Asia during this episode. Sensitivity analysis indicated that the Qingdao and Seoul regions experienced dust and pollution twice, by direct transport from the dust source region and from dust detoured over the Shanghai area. The results of the NAQPMS model confirmed the importance of dust heterogeneous reactions (HRs) over East Asia. Simulated dust NO₃⁻ concentrations accounted for 75% and 84% of total NO₃⁻ in fine and coarse mode, respectively, in Fukuoka, Japan. The horizontal distribution of model results revealed that the ratio of dust NO₃⁻/dust concentration increased from about 1% over the Chinese land mass to a maximum of 8% and 6% respectively in fine and coarse mode over the ocean to the southeast of Japan, indicating that dust NO₃⁻ was mainly formed over the Yellow Sea and the East China Sea before reaching Japan.

Exposure to fine particulate matter (PM₂.₅) is one of the leading risk factors for the mortality and morbidity burden in India. Health benefit expected from mitigation of emissions from individual sectors is the key policy information to address this issue. Here we quantify the relative shares of four major year-round anthropogenic sources to ambient PM₂.₅ in India using a chemical transport model and estimate premature deaths that could have been avoided due to complete mitigation of emissions from these sources at state level. Population-weighted all-India averaged (±1σ) annual ambient PM₂.₅ exposures due to residential, transport, industrial and energy sectors in 2010 are estimated to be 26.2 ± 12.5, 3.8 ± 4.3, 5.5 ± 2.7 and 2.2 ± 2.3 μg m⁻³, respectively. Complete mitigation of emissions from the transport, industrial and energy sectors combined would avoid 92,380 (95% uncertainty interval (UI), 40,918–140,741) premature deaths annually, primarily at the urban hotspots. For the residential sector, this would result in avoiding 378,295 (95% UI, 175,002–575,293) premature deaths due to a reduction in ambient PM₂.₅ exposure in addition to the benefit of avoiding all premature deaths from household exposure. Bihar and Goa are expected to have the largest (289) and smallest (48) premature mortality burden per 100,000 population due to anthropogenic PM₂.₅ exposure. From policy perspective, controlling residential sources should be prioritized in view of the effectiveness of implementing mitigation measures and the expected larger health benefit at a regional scale. However, additional mitigation measures are advised at the urban hotspots to curb emissions from the other sectors to get maximum possible health benefit.

The origin of PM₂.₅ has long been the subject of debate and stable isotopic tools have been applied to decipher. In this study, weekly PM₂.₅ samples were simultaneously collected at an urban (Seoul) and rural (Baengnyeong Island) site in Korea from January 2014 through February 2016. The seasonal variation of isotopic species showed significant seasonal differences with sinusoidal variation. The isotopic results implied that isotope species from Baengnyeong were mostly originated from coal combustion during China's winter heating seasons, whereas in summer, the isotopic patterns observed that were more likely to be from marine. In Seoul, coal combustion related isotopic patterns increased during China's winter heating period while vehicle related isotopic patterns were dominated whole seasons by default. Therefore, aerosol formation was originated from long-range transported coal combustion-related NOₓ by vehicle-related NH₃ in Seoul. δN-NH₄⁺ in Seoul showed highly enriched ¹⁵N compositions in all seasons, indicating that NH₃ from vehicle emission is the important source of NH₄⁺ in PM₂.₅ in Seoul. In addition, Baengnyeong should be consistently considered as a key region for observing the changes of isotopic features depend on the contribution of individual emissions to the atmospheric as a result of the reduction of coal consumption in China.