The effect of different Na concentrations on the fate of trace metals (Cd, Cu, Ni, Zn) in standard OECD soil was evaluated by performing soil leaching column experiments. Five Na concentrations added in synthetic irrigation water (0, 1, 5, 10, 50 mM) were studied in order to evaluate the fate of the metals contained in both the irrigation water leachate and the soil layer. In all experiments, metals mostly accumulated on the top soil layer (0–0.5 cm), at variable concentrations according to the Na content in the artificial irrigation water. Nevertheless, concentration peaks of metal contamination occurred at different sampling time in the soil leachates depending on the metal and on influent water sodicity. Peaks of metals in the leachate appeared simultaneously with the release of organic matter and/or release of Al, suggesting significant involvement of colloids in metals transport. Sodium concentration (10–50 mM) was demonstrated to highly reduce colloidal mobilization leading to the accumulation of more than 95% of the influent metal in the top soil layer. Conversely, low Na concentrations (1–5 mM) favored colloidal transport leading to the recovery of metals in the soil leachates.

A number of systematic reviews have investigated the association between air pollutants and health impacts, these mostly focus on morbidity and mortality from hospital data. Previously, no reviews focused solely on ambulance dispatch data. These data sets have excellent potential for environmental health research. For this review, publications up to April 2019 were identified using three main search categories covering: ambulance services including dispatches; air pollutants; and health outcomes. From 308 studies initially identified, 275 were excluded as they did not relate to ambulance service dispatches, did not report the air pollutant association, and/or did not study ambient air pollution. The main health outcomes in the remaining 33 studies were cardiac arrest (n = 14), cardiovascular (n = 11) and respiratory (n = 10) dispatches. Meta-analyses were performed to summarise pooled relative risk (RR) of pollutants: particulate matter less than 2.5 and 10 μm (PM₂.₅, PM₁₀), the fraction between PM₁₀ and PM₂.₅ (coarse) and suspended particulate matter (SPM) per 10 μg/m³ increase, carbon monoxide (CO) per 1 ppm increase and of sulphur dioxide (SO₂), nitrogen dioxide (NO₂), and ozone (O₃) per 10 ppb increment and ambulance dispatches. Statistically significant associations were found for ambulance dispatch data for all-respiratory and PM₂.₅ at 1.03 (95% CI:1.02–1.04) and at 1.10 (95% CI:1.00–1.21) for asthma and NO₂ associations. For dispatches with subsequent paramedic assessment for cardiac arrest with PM₂.₅, CO and coarse dispatches at 1.05 (95% CI:1.03–1.08), 1.10 (95% CI:1.02–1.18) and 1.04 (95% CI:1.01–1.06) respectively. For dispatches with subsequent physician diagnosis for all-respiratory and PM₂.₅ at 1.02 (95% CI:1.01–1.03). In conclusion, air pollution was significantly associated with an increase in ambulance dispatch data, including those for cardiac arrest, all-respiratory, and asthma dispatches. Ambulance services should plan accordingly during pollution events. Furthermore, efforts to improve air quality should lead to decreases in ambulance dispatches.

Current understanding of how environmental aging of microplastics contributes to their ecotoxicity is low. We investigated whether incubation of microplastics in waters with different organic load and toxic potential alters the toxicity of microplastics to crustacean Daphnia magna, fish embryos Danio rerio and plant Lemna minor. Polyethylene primary microplastics; specifically microbeads from facial scrub; were subjected to 3-weeks incubation in low affected spring water, river water, effluent from the municipal wastewater treatment plant (WWTP) and municipal landfill leachate. Primary microplastics had no acute effect on D. magna mobility and D. rerio embryos development. While high organic load wastewaters; WWTP effluent and landfill leachate; showed evident toxicity for D. magna and D. rerio embryos, microplastics aged in these wastewaters had no effect. This suggests that adsorption of pollutants from wastewaters to microplastic particles was not high enough to induce acute toxicity to D. magna and D. rerio. On the contrary, primary microplastics affected the root growth of L. minor. Interestingly, aging of microplastics in low organic-load waters mitigated the toxicity of microplastics for L. minor, while microplastics aged in high-organic load waters had the same adverse effect as primary microplastics. Partly, these effects can be explained by different extent of coating on microplastics in different water samples. This study suggests that aging of microplastics in wastewaters and natural waters did not significantly enhance the toxicity to selected test species, but further studies on plants may be of interest.

Epidemiological studies on the impact of outdoor temperature to human health have demonstrated the capability of humans to adapt to local climate. However, there is limited information on the association between indoor temperature and human health, despite people spending most of their time indoors. The problem stems from the lack of sufficient indoor temperature measurement in the population. To overcome this obstacle, this paper presents an indirect epidemiological approach to evaluate the impact of high indoor temperature on mortality. The relationships between indoor-outdoor temperatures in different climate zones identified in the literature were combined with the outdoor temperature-mortality curves of the same locations to obtain the local indoor minimum mortality temperatures (iMMT), the temperature at which mortality is lowest, which by implication is the temperature at which the population is most comfortable on average. We show that the iMMT varies and has a weak linear relationship with the distance to the equator, which provides evidence of human adaptation to local indoor temperatures. These findings reinforce the adaptive comfort theory, which states that people can adapt to local indoor environment and establish their thermal comfort. Recognising the human adaptability to local climate will direct flexible and optimized policy to protect public health against extreme temperature events. This will also help reduce energy consumption for regulating indoor temperature without compromising the occupants’ health.

Natural dissolved organic matter (DOM) produced in algal blooms and overgrowths of macrophyte changes the elimination and ecotoxicity of estrogens in freshwater lakes. The complexation of 17α-ethinylestradiol (EE2) and various DOMs, including the water- and sediment-derived DOMs from the algal-dominant zone in Lake Taihu (TW and TS, respectively) and the macrophyte-dominant zone in Poyang Lake (PW and PS, respectively), and the humic acid (HA), was investigated along with the subsequent effects on EE2 biodegradation. Dialysis equilibrium experiments showed that binding to DOM significantly decreased the freely soluble concentrations of EE2. The binding capacity of the five DOMs followed the order of PW < TW < PS ≈ TS < HA. A negative correlation was found between the organic-carbon-normalized sorption coefficient (logKDOC) and the absorption ratio (E₂/E₃) of DOM, indicating that the large sized, aromatic molecules were involved in the complexation. The reduced freely soluble concentrations of EE2 did not inhibit its biodegradation by an EE2-degrading strain, Rhodobacter blasticus. Conversely, the autochthonous-dominated water-derived DOMs stimulated a more extensive biodegradation of EE2 than the sediment-derived DOMs, and the existence of HA resulted in the smallest increase in EE2 biodegradation. The promoting effect was associated with the increased concentration, activity, and transforming rate of R. blasticus by the bioavailable components in DOM. The present study suggests that the significant impact of natural DOM should be fully considered when assessing the fate and ecological risks of estrogens in eutrophic waters.

3,3′-dichlorobiphenyl (PCB-11) is an emerging PCB congener widely detected in environmental samples and human serum, but its toxicity potential is poorly understood. We assessed the effects of three concentrations of PCB-11 on embryotoxicity and Aryl hydrocarbon receptor (Ahr) pathway interactions in zebrafish embryos (Danio rerio). Wildtype AB or transgenic Tg(gut:GFP) strain zebrafish embryos were exposed to static concentrations of PCB-11 (0, 0.2, 2, or 20 μM) from 24 to 96 h post fertilization (hpf), and gross morphology, Cytochrome P4501a (Cyp1a) activity, and liver development were assessed via microscopy. Ahr interactions were probed via co-exposures with PCB-126 or beta-naphthoflavone (BNF). Embryos exposed to 20 μM PCB-11 were also collected for PCB-11 body burden, qRT-PCR, RNAseq, and histology. Zebrafish exposed to 20 μM PCB-11 absorbed 0.18% PCB-11 per embryo at 28 hpf and 0.61% by 96 hpf, and their media retained 1.36% PCB-11 at 28 hpf and 0.84% at 96 hpf. This concentration did not affect gross morphology, but altered the transcription of xenobiotic metabolism and liver development genes, impeded liver development, and increased hepatocyte vacuole formation. In co-exposures, 20 μM PCB-11 prevented deformities caused by PCB-126 but exacerbated deformities in co-exposures with BNF. This study suggests that PCB-11 can affect liver development, act as a partial agonist/antagonist of the Ahr pathway, and act as an antagonist of Cyp1a activity to modify the toxicity of compounds that interact with the Ahr pathway.

An emission inventory of carbonyl sulfide (COS) from primary anthropogenic sources in China was compiled from 2010 to 2015. The national total emission was estimated at 174 Gg S yr⁻¹ in 2015, with an annually average sustainable growth rate of 7.2% from 2010 to 2015. Industrial sources, biomass burning, coal combustion, agricultural sources and vehicle exhaust contributed 68.2%, 22.0%, 6.1%, 2.2%, and 1.5%, respectively, of total COS emissions in 2015. Aluminum production, carbon black production, titania production, coke production, pulp and paper industry, were the main industrial sources of COS, with the emission about 118 Gg S yr⁻¹ COS in 2015, accounting for 98.5% of total direct emissions from the Chinese industry. The distribution of COS emissions in China showed significant differences at the provincial level. In Shandong and Xinjiang province, they were much bigger than other provinces, with total emissions of 31 and 15 Gg S yr⁻¹, respectively. Uncertainty analysis of COS emission inventories showed that the emission range was 70–267 Gg S yr⁻¹ at a 95% confidence interval. In this study, COS emissions in China were much higher than prior underestimated estimations, even for Asian and global emissions, which could be resolved part of missing sources in the global COS budget.

Parent polycyclic aromatic hydrocarbons (PPAHs) in the ambient air of the coastal cities near the Bohai and Yellow Seas were measured over a full year. The range and geometric average of total PPAH₂₉ (29 species) were 5.16-1.22 × 10³ and 118 ng/m³, respectively, with 77 ± 14% in a gaseous phase. The 16 priority components accounted for 90 ± 4% of the total mass concentration. The incremental life cancer risk (ILCR) via inhalation exposure to the PPAHs (3.17 × 10⁻⁴) was underestimated by 80%, as only the priority PPAHs were considered. The air concentrations of PPAHs in the Bohai Sea area were generally higher (p < 0.01) than those in the Yellow Sea area. A significant increase (p < 0.01) in the levels of PPAHs and large fractions of high molecular weight (HMW) components were observed in winter. Absorption by particulate organic carbon dominated in gas-particle partitioning of the PPAHs, and the seasonal variations in gas-particle partitioning of the low and moderate molecular weight compounds were more noticeable relative to the HMW species. In summer, significantly higher concentrations of PPAHs were found in the daytime than during nighttime, while the opposite case occurred in winter (p < 0.05). The positive matrix factorization (PMF) results indicated greater contributions of coal and biomass combustion to the PPAH emissions in the coastal cities of the Bohai Sea area compared with the Yellow Sea area. The burning of coal and biomass served as the main source of PPAHs in winter, while traffic exhaust was the dominant source in other seasons. The potential source contribution function (PSCF) revealed the important impacts of the external inputs on the local PPAHs via air mass transport. The contributions of the resolved emission sources to the ILCR were clearly different from those of the mass concentrations, indicating the necessity for source-oriented risk assessments.

Anthropogenic Pb emitted from East Asia, particularly China, is often long-range transported to the east by the prevailing westerlies. To characterize the geographical properties of varying atmospheric Pb concentrations by transboundary and domestic source(s)-related Pb in Korea, closely adjacent to China, the Al and Pb concentrations and the stable Pb isotopic composition were determined in the total suspended particles (TSP) collected at urban (IC), rural (TA), and remote background (JJ) sites in western Korea from August 2015 to October 2016. The annual average Pb concentrations were significantly higher in urban and rural areas (IC, 16.2 ng m⁻³ and TA, 11.1 ng m⁻³) than in remote area (JJ, 6.41 ng m⁻³), showing pronounced seasonal variations with relatively higher concentrations in winter and spring and lower concentrations in summer and autumn. Significantly high enrichment factors (EF) for Pb indicate that anthropogenic contributions are important for this toxic element in TSP. Coupling the Pb isotopic signatures with the air mass back trajectories identified the major potential source regions for individual samples. The results show that during winter, China was the dominant contributor, accounting for 92%, 82%, and 100% of the sampling periods at IC, TA, and JJ, respectively. The Chinese contribution decreased in summer and autumn, whereas the Korean contribution increased, according to the East Asian monsoon system. The Pb concentrations increased by 2.2 (IC), 1.2 (TA) and 1.4 (JJ) times when the Chinese contribution was dominant, compared to the Korea-dominant periods. The Pb isotopic systematics for the samples characterized by the dominant Korean contribution differed substantially between the three sites, implying that the relative importance of various domestic sources varied with geographical areas in western Korea.