Air pollutant levels depend on emissions but can also be affected by the meteorological situation. We examined air pollutant trends (PM₁₀, NO₂, O₃ and SO₂) in Slovenia, where in the past the main issue were SO₂ levels. Now, the population is still exposed to PM₁₀ and ozone levels that are above the recommended levels.Our goal was to assess if the levels of air pollutants were decreasing from 2002 to 2017 due to emission ceilings or were more influenced by changes in the meteorological situation. We modelled the relationship between levels, meteorological parameters, and seasonality and then used the models with the best estimated generalisation to adjust levels for meteorology. Models showed a significant relationship between meteorological parameters and PM₁₀, NO₂, and O₃ levels, but not SO₂. We analysed trends of raw and adjusted levels and compared them. Trends of PM₁₀ and SO₂ were decreasing at all locations for raw and adjusted data. The largest decrease was observed in SO₂ levels where the largest decrease in emissions occurred. Trends of NO₂ were also significant and negative at most locations. Levels of O₃ did not exhibit a significant trend at most locations.Results show that changes in the meteorological situation affected PM₁₀ levels the most, especially where the entire period (2002–2017) could be observed. There is strong empirical evidence that changes in meteorological parameters contributed to the decrease in PM₁₀ levels while the decrease in NO₂ and SO₂ levels can be attributed to emission ceilings.

In the present study, the daily dose in terms of particle surface area received by citizens living in five cities in Western countries, characterized by different lifestyle, culture, climate and built-up environment, was evaluated and compared. For this purpose, the exposure to sub-micron particle concentration levels of the population living in Barcelona (Spain), Cassino (Italy), Guilford (United Kingdom), Lund (Sweden), and Brisbane (Australia) was measured through a direct exposure assessment approach. In particular, measurements of the exposure at a personal scale were performed by volunteers (15 per each population) that used a personal particle counter for different days in order to obtain exposure data in microenvironments/activities they resided/performed. Non-smoking volunteers performing non-industrial jobs were considered in the study.Particle concentration data allowed obtaining the exposure of the population living in each city. Such data were combined in a Monte Carlo method with the time activity pattern data characteristics of each population and inhalation rate to obtain the most probable daily dose in term of particle surface area as a function of the population gender, age, and nationality.The highest daily dose was estimated for citizens living in Cassino and Guilford (>1000 mm²), whereas the lowest value was recognized for Lund citizens (around 100 mm²). Indoor air quality, and in particular cooking and eating activities, was recognized as the main influencing factor in terms of exposure (and thus dose) of the population: then confirming that lifestyle (e.g. time spent in cooking activities) strongly affect the daily dose of the population. On the contrary, a minor or negligible contribution of the outdoor microenvironments was documented.

The predicted long lag time between a decrease in atmospheric deposition and a measured response in vegetation has generally excluded the investigation of vegetation recovery from the impacts of atmospheric deposition. However, policy-makers require such evidence to assess whether policy decisions to reduce emissions will have a positive impact on habitats. Here we have shown that 40 years after the peak of SOₓ emissions, decreases in SOₓ are related to significant changes in species richness and cover in Scottish Calcareous, Mestrophic, Nardus and Wet grasslands. Using a survey of vegetation plots across Scotland, first carried out between 1958 and 1987 and resurveyed between 2012 and 2014, we test whether temporal changes in species richness and cover of bryophytes, Cyperaceae, forbs, Poaceae, and Juncaceae can be explained by changes in sulphur and nitrogen deposition, climate and/or grazing intensity, and whether these patterns differ between six grassland habitats: Acid, Calcareous, Lolium, Nardus, Mesotrophic and Wet grasslands. The results indicate that Calcareous, Mesotrophic, Nardus and Wet grasslands in Scotland are starting to recover from the UK peak of SOₓ deposition in the 1970's. A decline in the cover of grasses, an increase in cover of bryophytes and forbs and the development of a more diverse sward (a reversal of the impacts of increased SOₓ) was related to decreased SOₓ deposition. However there was no evidence of a recovery from SOₓ deposition in the Acid or Lolium grasslands. Despite a decline in NOₓ deposition between the two surveys we found no evidence of a reversal of the impacts of increased N deposition. The climate also changed significantly between the two surveys, becoming warmer and wetter. This change in climate was related to significant changes in both the cover and species richness of bryophytes, Cyperaceae, forbs, Poaceae and Juncaceae but the changes differed between habitats.

Mass concentrations of chemical compounds in both PM2.5 (particle aerodynamic diameter, Dp < 2.5 μm) and PM2.5-10 (2.5 < Dp < 10 μm), and acidity of aerosol particles were measured at an urban site in western Japan using a continuous dichotomous Aerosol Chemical Speciation Analyzer (ACSA-12) throughout 2014. Mass concentrations of both PM2.5 and sulfate had distinct seasonal variabilities with maxima in spring and winter, mostly due to long-range transport with the prevailing westerly wind. Mass concentration of nitrate in PM2.5 (fNO3) showed an obvious warm-season-low and cold-season-high pattern as a result of both gas-aerosol phase equilibrium processes under high temperature conditions as well as transport. Nitrate in PM2.5-10 (cNO3) increased during long-range transport of dust, implying the great importance of heterogeneous processes at the surface of coarse mode particles. In this study, Δ[H+] (derived from the difference in pH of extract liquid with/without sampling) was used to indicate the acidity of particles. We found that acidity of particles in PM2.5 (fΔH) was mostly positive with a maximum in August because of the large fraction of nitrate and sulfate. Acidity of particles in PM2.5-10 (cΔH) was negative in winter and spring due to presence of alkaline matter from crustal sources. This study highlights the great importance of anthropogenic pollutants on the acidity of particles in the western Pacific Ocean and further impact on the marine environment and climate.

The release of CeO2-bearing residues during the weathering of an acrylic stain enriched with CeO2 nanomaterial designed for wood protection (Nanobyk brand additive) was studied under two different scenarios: (i) a standard 12-weeks weathering protocol in climate chamber, that combined condensation, water spraying and UV–visible irradiation and (ii) an alternative accelerated 2-weeks leaching batch assay relying on the same weathering factors (water and UV), but with a higher intensity of radiation and immersion phases. Similar Ce released amounts were evidenced for both scenarios following two phases: one related to the removal of loosely bound material with a relatively limited release, and the other resulting from the degradation of the stain, where major release occurred. A non-linear evolution of the release with the UV dose was evidenced for the second phase. No stabilization of Ce emissions was reached at the end of the experiments. The two weathering tests led to different estimates of long-term Ce releases, and different degradations of the stain. Finally, the photo-degradations of the nanocomposite, the pure acrylic stains and the Nanobyk additive were compared. The incorporation of Nanobyk into the acrylic matrix significantly modified the response of the acrylic stain to weathering.

A limited but emerging body of evidence is suggestive for a beneficial association between contact with green spaces and glucose homeostasis in adults; however, such an evidence for children is scarce. We evaluated the association between time spent in green spaces and fasting blood glucose (FBG) levels and impaired fasting glucose (IFG, FBG≥110 mg/dL) in a population-based multicentric sample of 3844 Iranian schoolchildren aged 7–18 years (2015). Participants were instructed to report the average hours per week spent in green spaces separately during each season and in each type of green space (parks, woods/other natural green spaces, and private gardens/agricultural field) for a 12-month period preceding the interview. We developed linear and logistic mixed effects models with centre as random effect to evaluate the association of time spent in green spaces (separately for each type as well as all types together) with FBG and IFG, respectively, controlled for a wide range of covariates including household indicators of socioeconomic status. We observed inverse associations between time spent in green spaces, especially in natural green spaces, and FBG levels. Specifically, 1.83 h increase in the total time spent in green spaces was associated with −0.5 mg/dl (95% confidence intervals: −0.9, −0.1) change in FBG levels. We also observed reduced risk of IFG associated with time spent in green spaces; however, the association was statistically significant only for the time spent in natural green spaces. There were suggestions for stronger associations for those residing in urban areas and those from lower socioeconomic status groups; however, the interaction terms for socioeconomic status and urbanity were not statistically significant. Further longitudinal studies are required to replicate our findings in other settings with different climates and population susceptibilities.

Significant volumes of research over the past four decades has sought to elucidate the social, infrastructural, economic, and human health effects of climate change induced surface flooding. To date, epidemiological and public health studies of flooding events have focused on mental health effects, vector-borne diseases, and infectious enteric disease due to floodwater contact (i.e. typically low consumption rates). The inherent nature of groundwater (i.e. out of sight, out of mind) and the widely held belief that aquifers represent a pristine source of drinking water due to natural attenuation may represent the “perfect storm” causing direct consumption of relatively large volumes of surface flood-contaminated groundwater. Accordingly, the current study sought to systematically identify and synthesize all available peer-reviewed literature pertaining to the nexus between surface flooding, groundwater contamination and human gastroenteric outcomes. Just 14 relevant studies were found to have been published during the period 1980–2017, thus highlighting the fact that this potentially significant source of climate-related exposure to environmental infection has remained understudied to date. Studies differed significantly in terms of type and data reporting procedures, making it difficult to discern clear trends and patterns. Approximately 945 confirmed cases of flood-related enteric disease were examined across studies; these concurred with almost 10,000 suspected cases, equating to approximately 20 suspected cases per confirmed case. As such, no regional, national or global estimates are available for the human gastrointestinal health burden of flood-related groundwater contamination. In light of the demonstrable public health significance of the concurrent impacts of groundwater susceptibility and climate change exacerbation, strategies to increase awareness about potential sources of contamination and motivate precautionary behaviour (e.g. drinking water testing and treatment, supply interruptions) are necessary. Mainstreaming climate adaptation concerns into planning policies will also be necessary to reduce human exposure to waterborne sources of enteric infection.

Atmospheric pollution by polycyclic aromatic hydrocarbons (PAHs) has become a serious problem, especially in Asia, as PAHs can severely affect ecologically important mountainous areas. Using pine needles and mosses as bio-indicators, this study examined PAH pollution in a mountainous study area and evaluated the influence of transboundary PAHs. PAHs in urban areas were also evaluated for comparison. The study sites were alpine areas and urban areas (inland or coastal cities) across central Japan, in the easternmost part of Asia where atmospheric pollutants are transported from mainland Asia. The mean PAH concentrations of pine needles and mosses were 198.9 ± 184.2 ng g⁻¹ dry weight (dw) and 131.8 ± 60.7 ng g⁻¹ dw (mean ± SD), respectively. Pine needles preferentially accumulated PAHs with low molecular weights (LMW PAHs) and exhibited large differences in both PAH concentration and isomer ratios between alpine and urban sites. These differences can be explained by the strong influence of LMW PAHs emitted from domestic sources, which decreased and changed during transport from urban to alpine sites due to dry/wet deposition and photodegradation. In contrast, mosses accumulated a higher ratio of PAHs with high molecular weight (HMW PAHs). A comparison of isomer ratios showed that the PAH source for alpine moss was similar to that for northern coastal cities, which are typically influenced by long-transported PAHs from East Asia. Thus, these results indicate that alpine moss can also be strongly affected by the transboundary PAHs. It is likely that the uptake characteristics of moss, alpine climate, and alpine locations far from urban areas can strengthen the influence of transboundary pollution. Based on these results, the limitations and most effective use of bioindicators of PAH pollution for preserving alpine ecosystems are discussed.

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.

The bioremediation of historic industrial contaminated sites is a complex process. Co-contamination, often with lead which was commonly added to gasoline until 16 years ago is one of the biggest challenges affecting the clean-up of these sites. In this study, the effect of heavy metals, as co-contaminant, together with total petroleum hydrocarbons (TPH) is reported, in terms of remaining soil toxicity and the structure of the microbial communities. Contaminated soil samples from a relatively hot and dry climate in Western Australia were collected (n = 27). Analysis of soils showed the presence of both contaminants, TPHs and heavy metals. The Microtox test confirmed that their co-presence elevated the remaining ecotoxicity. Toxicity was correlated with the presence of lead, zinc and TPH (0.893, 0.599 and 0.488), respectively, assessed using Pearson Correlation coefficient factor. Next Generation Sequencing of soil bacterial 16S rRNA, revealed a lack of dominate genera; however, despite the variation in soil type, a few genera including Azospirillum spp. and Conexibacter were present in most soil samples (85% and 82% of all soils, respectively). Likewise, many genera of hydrocarbon-degrading bacteria were identified in all soil samples. Streptomyces spp. was presented in 93% of the samples with abundance between 7% and 40%. In contrast, Acinetobacter spp. was found in only one sample but was a dominant member of (45%) of the microbial community. In addition, some bacterial genera were correlated to the presence of the heavy metals, such as Geodermatophilus spp., Rhodovibrio spp. and Rubrobacter spp. which were correlated with copper, lead and zinc, respectively. This study concludes that TPH and heavy metal co-contamination significantly elevated the associated toxicity. This is an important consideration when carrying out risk assessment associated with natural attenuation. This study also improves knowledge about the dynamics of microbial communities in mixed contamination scenarios.