Given the lack of knowledge regarding climate change-chemical exposure interactions, it is vital to evaluate how these two drivers jointly impact aquatic species. Thus, for the first time, we aimed at investigating the combined effects of increased temperature, pCO2 and the synthetic progestin levonorgestrel on survival, growth, consumption rate and reproduction of the amphipod Gammarus locusta. For that, a full factorial design manipulating temperature [ambient temperature and warming (+4 °C)], pCO2 [normocapnia and hypercapnia (Δ pH 0.5 units)] and the progestin levonorgestrel (LNG: L1 – 10 ngLL−1 and L2 – 1000 ngLL−1, control – no progestin and solvent control – vehicle ethanol (0.01%)) was implemented for 21 days. G. locusta was strongly negatively affected by warming, experiencing higher mortality rates (50–80%) than in any other treatments. Instead, growth rates were significantly affected by interactions of LNG with temperature and pCO2. It was observed, in the short-term (7d) that under ambient temperature (18 °C) and hypercapnic conditions (pH 7.6), the LNG presence promoted the amphipod's growth, while in the medium-term (21d) this response was not observed. Relative consumption rates (RCRs), during the first week were higher than in the third week. Furthermore, in the first week, RCRs were negatively affected by higher temperature while in the third week, RCRs were negatively affected by acidification. Furthermore, it was observed a negative effect of higher temperature and acidification on G. locusta fecundity, contrarily to LNG. Concluding, the impact of increased temperature and pCO2 was clearly more adverse for the species than exposure to the synthetic progestin, however, some interactions between the progestin and the climate factors were observed. Thus, in a future scenario of global change, the presence of LNG (and other progestins alike) may modulate to a certain level the effects of climate drivers (and vice-versa) on the gammarids fitness and reproduction.

Nanosized particles (NPs), such as TiO₂, Silver, graphene NPs, nanoscale zero-valent iron, carbon nanotubes, etc., are increasingly used in industrial processes, and releases at production plants and from landfills are likely scenarios for the next years. As a consequence, appropriate procedures and tools to quantify the risks for human health associated to these releases are needed.The tiered approach of the standard ASTM procedure (ASTM-E2081-00) is today the most applied for human health risk assessment at sites contaminated by chemical substances, but it cannot be directly applied to nanoparticles: NP transport along migration pathways follows mechanisms significantly different from those of chemicals; moreover, also toxicity indicators (namely, reference dose and slope factor) are NP-specific. In this work a risk assessment approach modified for NPs is proposed, with a specific application at Tier 2 to migration in groundwater. The standard ASTM equations are modified to include NP-specific transport mechanisms. NPs in natural environments are typically characterized by a heterogeneous set of NPs having different size, shape, coating, etc. (all properties having a significant impact on both mobility and toxicity). To take into account this heterogeneity, the proposed approach divides the NP population into classes, each having specific transport and toxicity properties, and simulates them as independent species. The approach is finally applied to a test case simulating the release of heterogeneous Silver NPs from a landfill. The results show that taking into account the size-dependent mobility of the particles provides a more accurate result compared to the direct application of the standard ASTM procedure. In particular, the latter tends to underestimate the overall toxic risk associated to the nP release.

Avoidance behaviour offers a highly relevant information as it reveals the ability to avoid (or not) possible toxic compounds in the field, hence it provides information on reasons for the presence/absence in the field. The earthworm Eisenia fetida was used to study avoidance behaviour to four silver forms (three nanomaterials (NMs) and one salt) over four time points (24, 48, 72 and 96 h), using OECD standard soil. Avoidance behaviour depended on both exposure material and concentration, but in general changed little with exposure duration. Avoidance was highest for the salt (AgNO₃) for all exposure durations and showed a continuous higher avoidance with time (based on EC₅₀ values). The AgNMs avoidance was in the order NM300K<AgNM-non coated = AgNM- PVP coated. It was not possible to identify one soil solution fraction that correlated with EC₅₀ across materials.

This paper presents a detailed study on the indoor air pollution in the Jokahng Temple at Tibet Plateau, and its implication to human health. The mean concentrations of PM1.0 and PM2.5 were 435.0 ± 309.5 and 483.0 ± 284.9 μg/m3, respectively. The PM2.5 concentration exceeded the National Ambient Air Quality Standard (75 μg/m3) by 6.4 times. The size-segregated aerosols displayed a bimodal distribution. One peak was observed in the fine mode (0.4–2.1 μm) and the other peak appeared in the coarse mode (2.1–9.0 μm). The concentration of the total size-resolved PM was 794.3 ± 84.9 μg/m3. The mass fraction of coarse particles shared by 41.1%, apparently higher than that reported at low altitudes, probably due to incomplete combustion at Tibet Plateau with hypoxic atmospheric environment. The total concentration of polycyclic aromatic hydrocarbons (PAHs) was 331.2 ± 60.3 ng/m3, in which the concentration of benzo(a)pyrene (BaP) was 18.5 ± 4.3 ng/m3, over ten times higher than the maximum permissible risk value of 1 ng/m3 on account of carcinogenic potency of particulate PAHs through inhalation. PAHs exhibited a trimodal distribution, of which two peaks were observed in the fine mode and one peak in the coarse mode. With the aromatic rings increasing, the peak intensity increased in the fine mode. Na, Ca, Al, Mg and K dominated the elemental mass profiles, and metals displayed a bimodal distribution with a dominant peak in the coarse range. The total PAH deposition flux was 123.6 and 53.1 ng/h for adults and children, respectively. Coarse particles contributed most deposition flux in the head region, while fine particles contribute most deposition flux in the alveolar region. The increment lifetime cancer risk (ILCR) of PAHs ranaged at 10−5-10−4, indicating potential cancer risk to human health. The total deposition flux of metals was estimated at 1.4–13.2 ng/h. With the size increasing, deposition flux increased in the head region while decreased in the alveolar region. The highest ILCR of Cr and Ni were 4.9 × 10−5 and 1.5 × 10−6, respectively, exceeding the permissible risk of 10−6. The hazard quotient (HQ) of Fe (10−5-10−4) and Zn (10−6-10−5) were much lower than the safe level of 1.0, and thus they were not considered as a health concern.

Microplastics are widespread throughout aquatic environments. However, there is currently insufficient understanding of the factors influencing ingestion of microplastics by organisms, especially higher predators such as fish. In this study we link ingestion of microplastics by the roach Rutilus rutilus, within the non-tidal part of the River Thames, to exposure and physiological factors. Microplastics were found within the gut contents of roach from six out of seven sampling sites. Of sampled fish, 33% contained at least one microplastic particle. The majority of particles were fibres (75%), with fragments and films also seen (22.7% and 2.3% respectively). Polymers identified were polyethylene, polypropylene and polyester, in addition to a synthetic dye. The maximum number of ingested microplastic particles for individual fish was strongly correlated to exposure (based on distance from the source of the river). Additionally, at a given exposure, the size of fish correlated with the actual quantity of microplastics in the gut. Larger (mainly female) fish were more likely to ingest the maximum possible number of particles than smaller (mainly male) fish. This study is the first to show microplastic ingestion within freshwater fish in the UK and provides valuable new evidence of the factors influencing ingestion that can be used to inform future studies on exposure and hazard of microplastics to fish.

While increasing evidence suggested that PM₂.₅ is the most harmful fraction of the particle pollutants, the health effects of coarse particles (PM₁₀–₂.₅) have been inconclusive, especially on cerebrovascular diseases, we thus evaluated the effects of PM₁₀, PM₂.₅, and PM₁₀–₂.₅ on stroke mortality in six Chinese subtropical cities using generalized additive models. We also conducted random-effects meta-analyses to estimate the overall effects across the six cities. We found that PM₁₀, PM₂.₅, and PM₁₀₋₂.₅ were significantly associated with stroke mortality. Each 10 μg/m³ increase of PM₁₀, PM₂.₅ and PM₁₀₋₂.₅ (lag03) was associated with an increase of 1.88% (95% CI: 1.37%, 2.39%), 3.07% (95% CI: 2.35%, 3.79%), and 5.72% (95% CI: 3.82%, 7.65%) in overall stroke mortality. Using the World Health Organization's guideline as reference concentration, we estimated that 3.21% (95% CI: 1.65%, 3.01%) of stroke mortality (corresponding to 1743 stroke mortalities, 95% CI: 896, 1633) were attributed to PM₁₀, 5.57% (95% CI: 0.50%, 1.23%) stroke mortality (3019, 95% CI: 2286, 3777) were attributed to PM₂.₅, and 2.02% (95% CI: 1.85%, 3.08%) of stroke mortality (1097, 95% CI: 1005, 1673) could be attributed to PM₁₀₋₂.₅. Our analysis indicates that both PM₂.₅ and PM₁₀₋₂.₅ are important risk factors of stroke mortality and should be considered in the prevention and control of stroke in the study area.

Organic UV stabilizers and UV filters are applied to industrial materials and cosmetics worldwide. In plastics they prevent photo-induced degradation, while in cosmetics they protect human skin against harmful effects of UV radiation. This study reports on the occurrence and distribution of organic UV stabilizers and UV filters in the surface sediment of the Chinese Bohai and Yellow Seas for the first time. In total, 16 out of 21 analyzed substances were positively detected. Concentrations ranged from sub-ng/g dw to low ng/g dw. The highest concentration of 25 ng/g dw was found for octocrylene (OC) in the Laizhou Bay. In the study area, characteristic composition profiles could be identified. In Korea Bay, the dominating substances were OC and ethylhexyl salicylate (EHS). All other analytes were below their method quantification limit (MQL). Around the Shandong Peninsula, highest concentrations of benzotriazole derivatives were observed in this study with octrizole (UV-329) as the predominant compound, reaching concentrations of 6.09 ng/g dw. The distribution pattern of UV-329 and bumetrizole (UV-326) were related (Pearson correlation coefficient r > 0.98, p « 0.01 around the Shandong Peninsula), indicating an identical input pathway and similar environmental behavior.

The wide usage of hexachlorocyclohexanes (HCHs) as pesticides has caused soil pollution and adverse health effects through direct contact or bioaccumulation in the food chain. This study quantified major HCH isomers in farmland topsoils across China, and evaluated their correlations with microbial community structure, function, and abiotic variables (e.g., moisture, pH, and temperature). Recalcitrant β-HCH was more abundant than α-, γ-, and δ-HCHs, and α-HCH enantiomeric fractions (EF) were larger than 0.5, indicating preferential degradation of (−)-α-HCH. Sphingomonas was not only a predominant population (especially in samples collected in the south), but also a promising biomarker indicating total- and β-HCH residuals, and EF values of α-HCH. Soil moisture and temperature were among the most influential factors that structured the diversity and function of soil microbial communities. The results suggested that increasing soil moisture (in the range of 5–45%) would benefit the growth of HCH-degrading populations and the enrichment of HCH-degradation related pathways. Revealing the site-specific relationships between topsoil physical, chemical, and microbial properties will benefit the in situ bioremediation of farmlands with relatively low HCH residuals across the world.

Due to the activities inherent to medical care units, the hospital effluent released contains diverse contaminants such as tensoactives, disinfectants, metals, pharmaceutical products and chemical reagents, which are potentially toxic to the environment since they receive no treatment or are not effectively removed by such treatment before entering the drain. They are incorporated into municipal wastewater, eventually entering water bodies where they can have harmful effects on organisms and can result in ecological damage. To determine the toxicological risk induced by this type of eflluents, eight metals and 11 pharmaceuticals were quantified, in effluent from a hospital. Developmental effects, teratogenesis and oxidative stress induction were evaluated in two bioindicator species: Xenopus laevis and Lithobates catesbeianus. FETAX (frog embryo teratogenesis assay–Xenopus) was used to obtain the median lethal concentration (LC50), effective concentration inducing 50% malformation (EC50), teratogenic index (TI), minimum concentration to inhibit growth (MCIG), and the types of malformation induced. Twenty oocytes in midblastula transition were exposed to six concentrations of effluent (0.1, 0.3, 0.5, 0.7, 0.9, 1%) and negative and positive (6-aminonicotinamide) controls. After 96 h of exposure, diverse biomarkers of oxidative damage were evaluated: hydroperoxide content, lipid peroxidation, protein carbonyl content, and the antioxidant enzymes superoxide dismutase and catalase. TI was 3.8 in X. laevis and 4.0 in L. catesbeianus, both exceed the value in the FETAX protocol (1.2), indicating that this effluent is teratogenic to both species. Growth inhibition was induced as well as diverse malformation including microcephaly, cardiac and facial edema, eye malformations, and notochord, tail, fin and gut damage. Significant differences relative to the control group were observed in both species with all biomarkers. This hospital effluent contains contaminants which represents a toxic risk, since these substances are teratogenic to the bioindicators used. The mechanism of damage induction may be associated with oxidative stress.

Spatial and seasonal variations in nitrate contamination are a globally concern. While numerous studies have used δ¹⁵N-NO₃ and δ¹⁸O-NO₃ to elucidate the dominant sources of nitrate in groundwater, this approach has significant limitations due to the overlap of nitrate isotopic ranges and the occurrence of nitrate isotopic fractionation. This study quantitatively assessed the spatial and seasonal variations in the proportional contributions of nitrate sources from different land uses in the Tarom watershed in North-West Iran. To achieve this aim, orthogonal projection of the hydrochemical and isotopic dataset of the principal component analysis (PCA) as well as correlation coefficient matrix (Corr-PCA) were evaluated to reduce the dimensionality of the inter-correlated dataset. Next, a nitrate isotopic biplot accompanied with a Bayesian isotope mixing model (SIAR) were applied to specify the spatial and seasonal trends in the proportional contribution of three dominant sources of nitrate (fertilizers, animal manure and residential waste) in the watershed. Finally, in order to provide a sensitive framework for nitrate source appointment and overcome the associated limitations of dual nitrate isotope application, the integration of boron isotope (δ¹¹B) and strontium isotopic ratio (⁸⁷Sr/⁸⁶Sr) was introduced. The results revealed that the mean contribution of residential sewage increased (17%–27.5%), while the mean contribution of fertilizers decreased (28.3%–19%), from late spring to early autumn. Also, fertilizer was the highest contributor (42.1% ± 3.2) during late spring, especially in regions with more than 75% agricultural land. Meanwhile, the mean contribution of sewage was highest in early autumn (32.1% ± 2.8) in the areas with more than 20% residential land. These results were confirmed by coupled application of δ¹¹B and ⁸⁷Sr/⁸⁶Sr. This study provides a useful insight for environmental managers to verify groundwater pollution contributors and to better apply remedial solutions.