Groundwater with elevated As concentrations is a global concern, and low-cost, high-efficiency removal technologies are necessary. Therefore, we have prepared three adsorbent FeMnLa-impregnated biochar composites (FMLBCs) for the efficient removal of As(III) from aqueous solutions and characterized them using a variety of techniques. We found that the efficiency of As(III) removal increased with increasing La content and that the removal mainly occurred via adsorption and oxidation. Moreover, the removal of As(III) by FMLBCs was rapid and was best fitted to a pseudo-second-order kinetic model. The adsorption isotherms were well described by the Langmuir equation, and the maximum As(III) adsorption capacity was 15.34 mg g⁻¹. These results highlight the significant potential of FMLBCs as adsorbents for As(III) removal from aqueous solutions.

Microbes in sediments contribute to nutrient release and play an important role in lake eutrophication. However, information about the profiles of functional genes and bacterial communities and the most important environmental factor affecting them in the sediments of eutrophic lake remains unrevealed. In this work, the real-time fluorescent quantitative polymerase chain reaction (qPCR) assay and 16S ribosomal RNA gene next generation sequencing analysis were used to explore the profiles of functional genes and bacterial communities in the sediments of Chaohu Lake. The selected 18 functional genes involved in C, N and P cycles were detected in most of samples. Seasonal variation and sediment variables were found to affect the profiles of functional genes and bacterial communities, and total nitrogen was the dominant environmental factor to drive the formation of bacterial community structure. Proteobacteria and Firmicutes were observed to be the two dominant phyla in the sediments with relative abundance ranging from 10.8% to 36.0% and 7.7%–46.7%, respectively. Three bacterial phyla, i.e., Actinobacteria, Proteobacteria, and Spirochaetes, were found to be significantly positively correlated with the C, N and P-cycle related functional genes. Bacterial community structure was the most important driver to shape the profiles of functional genes. Seasonal variation also influenced the co-occurrence patterns between functional genes and bacterial taxa as revealed by network analysis. The findings from this work facilitate a better understanding about the C, N, and P cycles in the sediments of eutrophic lakes.

Harbor porpoises (Phocoena phocoena) in the North and Baltic Seas are exposed to anthropogenic influences including acoustic stress and environmental contaminants. In order to evaluate immune responses in healthy and diseased harbor porpoise cells, cytokine expression analyses and lymphocyte proliferation assays, together with toxicological analyses were performed in stranded and bycaught animals as well as in animals kept in permanent human care. Severely diseased harbor porpoises showed a reduced proliferative capacity of peripheral blood lymphocytes together with diminished transcription of transforming growth factor-β and tumor necrosis factor-α compared to healthy controls. Toxicological analyses revealed accumulation of polychlorinated biphenyls (PCBs), dichlorodiphenyldichloroethylene (DDE), and dichlorodiphenyltrichloroethane (DDT) in harbor porpoise blood samples. Correlation analyses between blood organochlorine levels and immune parameters revealed no direct effects of xenobiotics upon lymphocyte proliferation or cytokine transcription, respectively. Results reveal an impaired function of peripheral blood leukocytes in severely diseased harbor porpoises, indicating immune exhaustion and increased disease susceptibility.

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.

Potential impacts of change in climate on Indian agriculture may be significantly adverse, if not disastrous. There are projections of potential loss in wheat yield due to the rise in daily minimum (Tmin) and maximum (Tmax) temperature, but only few researchers have considered the extent of such loss on a spatial scale. We therefore, systematically studied the effect of change in Tmax, Tmean (daily average temperature) and Tmin, solar radiation (Srad) and precipitation (RAIN) during wheat growing seasons (from 1986 to 2015) on wheat crop yield over five wheat growing zones across India, taking into account the effect modification by aerosol loading (in terms of aerosol optical depth, 2001–2015). We note that for the entire India, 1 °C rise in Tmean resulted a 7% decrease in wheat yield which varied disproportionately across the crop growing zones by a range of −9% (peninsular zone, PZ) to 4% (northern hills zone, NHZ). The effect of Tmean on wheat yield was identical to the marginal effect of Tmax and Tmin, while 1% increase in Srad enhance wheat yield by 4% for all India with small geographical variations (2–5%), except for the northern hill region (−4%). Rise in 1 °C Tmean exclusively during grain filling duration was noted positive for all the wheat growing regions (0–2%) except over central plain zone (−3%). When estimates of weather variables on wheat yield was combined with the estimated impact of aerosols on weather, the most significant impact was noted over the NHZ (−23%), which otherwise varied from −7% to −4%. Overall, the study brings out the conclusive evidence of negative impact of rising temperature on wheat yield across India, which we found spatially inconsistent and highly uncertain when integrated with the compounding effect of aerosols loading.

Large amounts of short chain and medium chain chlorinated paraffins (SCCPs and MCCPs) are released into the environment during production and usage. However, compared to SCCPs, there is a significant lack of attention for MCCPs. In this work, 83 air samples, collected between 2012 and 2015 from the Tibetan Plateau, were analyzed to investigate the airborne levels and distributions of MCCPs, further to evaluate their potential long-range transport behavior on the alpine area. The total air MCCP concentrations at Shergyla Mountain and Lhasa were between 50 and 690 pg/m3 and 800–6700 pg/m3, respectively. At Shergyla Mountain, MCCP concentrations in the air appeared an increasing trend with altitude, which indicated that MCCPs could potentially possess the ability of “mountain cold trapping”. C14 and C15 congener groups were the dominant homologue groups. The mountain contamination potential (MCP) of different congener groups is closely related to their equilibrium partitioning coefficients between octanol and air (KOA), and water and air (KWA). Increasing MCCPs levels might be a potential threat to the environment and human exposure.

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.

Prothioconazole (PTC) is a widely used triazolinthione fungicide with low toxicity and short residual period. However, its desulfurization metabolite, prothioconazole-desthio (PTC-d), is more persistent and has higher toxicity in terrestrial animals. In this study, the toxicokinetics (TK) and tissue distribution of PTC and PTC-d in Chinese lizards (Eremias argus) were measured following single oral dose (100 mg kg⁻¹ body weight) treatments. TK parameters indicated that PTC was more rapidly absorbed than PTC-d, as indicated by its shorter time to reach peak concentrations in most tissues. Furthermore, the relative bioavailability of PTC in lizards was lower than that of PTC-d. Compared with PTC, PTC-d preferentially accumulated in lizards, as reflected by longer half-life of PTC-d. During the distribution process, PTC-d generated in vivo was transported from other tissues and was deposited in the skin and tail, where PTC-d may be excreted by exuviation or tail detachment. Preferential enrichment of S-enantiomer of both PTC and PTC-d were observed in all tissues. Hepatic cytochrome P450 gene expression measurement revealed that cyp1a5 and cyp3a28 exhibited the strongest responses in both treatment groups. In addition, the opposite responses of cyp2k4 in different treatment groups may indicate that this enzyme caused differences in the rates of metabolism of the two chemicals. This study compared the TK profile of PTC and its desulfurization metabolite PTC-d in lizards and demonstrated that the desulfurization of PTC could increase its ecological risk due to the higher bioavailability and persistence of PTC-d.

The trophic balance of freshwater aquaculture activities has traditionally been monitored by chemical analysis of water; however, the parameters measured are usually characterized by high temporal variability. Aquatic mosses can be used as biomonitors as they integrate both continuous and episodic contamination events. Here we report, for the first time, a method for monitoring N enrichment in the surroundings of fish farms by measuring the N content and isotopic signal (δ15N) of transplanted living and devitalized specimens of the aquatic moss Fontinalis antipyretica. For this purpose, moss samples (“moss bags”) were exposed at increasing distances (10, 100, 300 and 1000 m) up- and downstream of the effluent discharge points of four trout farms, for 10 and 30 days. The low natural (background) variability in δ15N in upstream samples enabled detection of outlier values, caused by aquaculture discharges, at distances of 10 and 100 m downstream, especially in devitalized moss and after 10 days of exposure. However, the unexpectedly low N contents of moss samples exposed close to the discharge points complicates interpretation of the high levels of N forms detected by conventional physicochemical analysis of water. Although the mechanisms that modify N parameters in moss tissues were not clear, measurement of the isotopic signal δ15N in devitalized moss exposed for 10 days proved useful for monitoring the N pollution associated with intensive freshwater aquaculture.

Removal of toxic formaldehyde from environmental waters is crucial to maintain ecosystem sustainability and human health. In this work, MIL-100(Fe) as a heterogeneous Fenton-like photocatalyst was used for the treatment of formaldehyde-contaminated water. The MIL-100(Fe) was synthesized via a facile solvothermal method and fully characterized using different spectroscopic and microscopic techniques. Based on the results, the formation of highly porous, crystalline, and stable visible light-responsive MIL-100(Fe) was confirmed. The Fenton-like photocatalytic efficiency of the MIL-100(Fe) toward the degradation of formaldehyde was then studied under visible light irradiation. For this purpose, the effect of initial concentration of formaldehyde, photocatalyst dose, H₂O₂ concentration, solution pH, and contact time on the removal efficiency of the MIL-100(Fe) was investigated using central composite design. The obtained results showed that the removal efficiency of the MIL-100(Fe) is significantly affected by the initial concentration of formaldehyde. A second-order model with R² = 0.93 was developed for the system that was able to adequately predict the percentage removal of formaldehyde by the MIL-100(Fe) under different experimental conditions. According to the numerical optimization results, by using 1.13 g L⁻¹ photocatalyst and 0.055 mol L⁻¹ H₂O₂, 93% of formaldehyde can be removed after 119 min from an aqueous solution containing 700 mg L⁻¹ of formaldehyde at pH 6.54.