The widespread use of rare earth elements (REEs) in numerous sectors have resulted in their release into the environment. Existing knowledge about the effects of REEs were acquired mainly based on toxicity tests with aquatic organisms and a fixed exposure time, Here, the dynamic accumulation and toxicity of REEs (La, Ce, and Gd) in soil organism Enchytraeus crypticus were determined and modeled by a first-order one-compartment model and a time-toxicity logistic model, respectively. Generally, the accumulation and toxicity of REEs were both exposure level- and time-dependent. The overall uptake rate constants were 2.97, 2.48, and 2.38 L kg⁻¹d⁻¹ for La, Ce, and Gd, respectively. The corresponding elimination rate constants were 0.99, 0.78, and 0.56 d⁻¹, respectively. The worms exhibited faster uptake and elimination ability for light REEs (La and Ce) than for heavy REEs (Gd). For all three REEs, the LC50 values based on exposure concentrations decreased with time and reached ultimate values after approximately 10 d exposure. The estimated ultimate LC50 values (LC50∞) were 279, 334, and 358 mg L⁻¹ for Ce, Gd, and La, respectively. When expressed as body concentration, the LC50ᵢₙₜₑᵣ value was almost constant with time, demonstrating that internal body concentration could be a better indicator of dynamic toxicity of REEs than external dose. This study highlights that specific REE and exposure time should be taken into account in accurately assessing risk of REEs.

The sorption behaviour of three perfluoroalkyl substances (PFASs), namely perfluorooctane sulfonic acid (PFOS), perfluorooctanoic acid (PFOA) and perfluorohexane sulfonic acid (PFHxS), was determined on 28 tropical soils. Tropical soils are often highly weathered, richer in sesquioxides than temperate soils and may contain variable charge minerals. There are little data on sorption of PFASs in tropical soils. The highest Kd values were found for PFOS with mean values ranging from 0 to 31.6 L/kg. The Kd values for PFOA and PFHxS ranged from 0 to 4.9 L/kg and from 0 to 5.6 L/kg, respectively. While these values are in the range of literature sorption data, the average Kd values for PFOS and PFOA from the literature were 3.7 times and 3.6 times higher, respectively, than those measured in this study. Stepwise regression analysis did explain some of the variance, but with different explanatory variables for the different PFASs. The main soil properties explaining sorption for PFOS and PFOA were oxalate-extractable Al and pH, and for PFHxS was pH.

Many studies show that bisphenol A (BPA) is widespread in human breast milk. However, the occurrence of other bisphenol analogues (BPs), including bisphenol S (BPS), bisphenol F (BPF), and bisphenol AF (BPAF), in breast milk is still not well known. In this study, breast milk samples were collected from 190 women in Hangzhou, China, with the aims to characterize the occurrence of BPA, BPS, BPF, and BPAF in these samples and to investigate their effects on postnatal growth of infants through breast milk consumption. BPA (mean 2.5 ng/mL, range < LOD–15 ng/mL) was the most abundant BP in breast milk, followed by BPS (0.19 ng/mL, <LOD–1.3 ng/mL) and BPAF (0.092 ng/mL, <LOD–0.58 ng/mL). BPF was not detected in all breast milk samples. We firstly found that breast milk concentrations of BPA were negatively correlated with infant’s weight or length gain rate. Daily intakes (DIs) of BPs via the consumption of breast milk were calculated for infants, and the mean DI values were 531 ng/kg/day, 53 ng/kg/day, and 24 ng/kg/day for BPA, BPS, and BPAF, respectively. Overall, this study firstly demonstrats that the lactation exposure to BPA through breast milk consumption may affect the postnatal growth of infants.

The proportion of asthma patients with mild to moderate exacerbations is far greater than the number who experience episodes that are severe enough to require emergency room visits or hospital admission. However the routinely collected data from hospitals is absent in the past.To evaluate associations between short-term exposures to air pollutants and hospital outpatient visits for asthma in China.We obtained data for 143,057 asthma outpatient visits from the largest hospitals in 17 Chinese cities, between Jan 01 2013 and Dec 31 2015. We used daily concentrations of air pollutants measured by the China National Environmental Monitoring Centre. We used a time-stratified case-crossover design, and fitted conditional logistic regression models to determine the associations.Particulate matter ≤10μm in diameter (PM10) and nitrogen dioxide (NO2) were associated with increased risks of hospital outpatient visits for asthma on the same day, while the effects were delayed for particulate matter ≤2.5μm in diameter (PM2.5) and sulphur dioxide (SO2). For the cumulative effect model at lag05 days, 10 μg/m3 increase in air pollutants concentrations were correlated with hospital outpatient visits for asthma with odds ratios (ORs) and 95% confidence intervals 1.004 (1.000-1.008) for PM2.5, 1.005 (1.002-1.008) for PM10, 1.030 (1.021-1.040) for NO2, and 1.015 (1.008-1.021) for SO2. Almost one in nine (10.9%; 7.7, 13.9%) hospital outpatient visits for asthma were attributable to NO2.Short-term exposures to PM2.5, PM10, NO2 and SO2 were associated with hospital outpatient visits for asthma in China.

Compound-specific stable isotope analysis of micropollutants has become an established method for the qualitative and quantitative assessment of biodegradation in the field. However, many of environmental factors may have an influence on the observed isotope fractionation. Herein, we investigate the impact of substrate concentration on the observed enrichment factor derived from Rayleigh plot of batch laboratory experiments conducted to measure the atrazine carbon isotope fractionation of Rhizobium sp. CX-Z subjected to the different initial concentration level of atrazine. The Rayleigh plot (changes in bulk concentration vs. isotopic composition) derived from batch experiments shown divergence from the linear relation towards the end of degradation, confirming bioavailability of atrazine changed along with the decay of substrate concentration, consequently, influenced the isotope fractionation and lowered the observed enrichment factor. When microbial degradation is coupled to a mass transfer step limiting the bioavailability of substrate, the observed enrichment factor displays a dependence on initial atrazine concentration. Observed enrichment factors (ε) (absolute value) derived from the low concentration (i.e. 9.5 μM) are below 3.5‰ to the value of −5.4‰ determined at high bioavailability (membrane-free cells). The observed enrichment factor depended significantly on the atrazine concentration, indicating the concentration level and the bioavailability of a substrate in realistic environments should be considered during the assessment of microbial degradation or in situ bioremediation based on compound-specific stable isotope analysis (CSIA) method.

The novel coronavirus disease (COVID-19) is primarily respiratory in nature, and as such, there is interest in examining whether air pollution might contribute to disease susceptibility or outcome. We merged data on COVID-19 cumulative prevalence and fatality rates as of May 31, 2020 with 2014–2019 pollution data from the US Environmental Protection Agency Environmental Justice Screen (EJSCREEN), with control for state testing rates, population density, and population covariate data from the County Health Rankings. Pollution data included three types of air emission concentrations (particulate matter<2.5 μm (PM2.5), ozone and diesel particulate matter (DPM)), and four pollution source variables (proximity to traffic, National Priority List sites, Risk Management Plan (RMP) sites, and hazardous waste treatment, storage and disposal facilities (TSDFs)). Results of mixed model linear multiple regression analyses indicated that, controlling for covariates, COVID-19 prevalence and fatality rates were significantly associated with greater DPM. Proximity to TSDFs was associated to greater fatality rates, and proximity to RMPs was associated with greater prevalence rates. Results are consistent with previous research indicating that air pollution increases susceptibility to respiratory viral pathogens. Results should be interpreted cautiously given the ecological design, the time lag between exposure and outcome, and the uncertainties in measuring COVID-19 prevalence. Areas with worse prior air quality, especially higher concentrations of diesel exhaust, may be at greater COVID-19 risk, although further studies are needed to confirm these relationships.

Water management such as drainage for creating aerobic conditions is considered to be an adequate method for reducing the accumulation of arsenic (As) in rice grains; however, it is difficult to conduct drainage operations in some areas that experience a lengthy rainy season as well as in soils with poor drainage. In this regard, application of oxygen-releasing compounds (ORCs) may be an alternative method for maintaining aerobic conditions even under flooding in paddy soils. Therefore, a pot experiment was conducted to investigate the effects of application of an ORC, calcium peroxide (CaO₂), on the growth and accumulation of As in rice plants grown in As-contaminated paddy soils. The rice plants were grown in two soils with different characteristics and As levels, and all of the tested soils were treated with 0, 5, 10, and 20 g CaO₂ kg⁻¹. Results revealed that the concentration of As and the distribution of arsenite in the pore water of all tested soils was reduced by CaO₂ application. In addition, the grain yields increased and the concentration of inorganic As in brown rice decreased by 25–45% upon CaO₂ treatment of low-As-level soils (<16 mg kg⁻¹). However, the effect of CaO₂ application on the accumulation of inorganic As in brown rice in As-enriched soils (>78 mg kg⁻¹) could not found in this study, due to the rice plant suffered from serious As phytotoxicity. It suggests that CaO₂ amendment may be suitable for reducing the As concentration of rice grains grown in low-As-level paddy soils, but for As-enriched soils, the proposed CaO₂ application method is not feasible.

Several harbour activities cause negative environmental impacts in the harbours’ surrounding areas, namely the degradation of air quality. This paper intends to comprehensively review the status of the air quality measured in harbour areas. The published studies show a limited number of available air quality monitoring data in harbours areas, mostly located in Europe (71%). Measured concentrations of the main air pollutants were compiled and intercompared, for different countries worldwide allowing a large spatial representativeness. The higher NO₂ and PM₁₀ concentrations were found in Europe - ranging between 12 and 107 μg/m³ and 2–50 μg/m³, respectively, while the higher concentrations of PM₂.₅ were found in Asia (25–70 μg/m³). In addition, the lower levels of SO₂ monitored in recent years suggest that current mitigation strategies adopted across Europe were very efficient in promoting the reduction of SO₂ concentrations.Part of the reviewed studies also estimated the contributions from ship emissions to PM concentration through the application of source apportionment methods, with an average of 5–15%. In some specific harbour areas in Asia, ships can contribute up to 7–26% to the local fine particulate matter concentrations. This review confirms that emissions from the maritime transport sector should be considered as a significant source of particulate matter in harbour areas, since this pollutant concentrations are frequently exceeding the established standard legal limit values. Therefore, the results from this review boost the implementation of mitigation measures, aiming to reduce, in particular, particulate matter emissions.

Emerging evidence has shown that exposure to ambient fine particulate matter (PM₂.₅) is associated with hepatic lipid accumulation. However, the underlying mechanism is not fully characterized yet. Autonomous circadian clock in the liver plays a fundamental role in maintaining lipid metabolism homeostasis. In this study, we evaluated the effects of ambient PM₂.₅ exposure on the expression of hepatic circadian clock genes and expression rhythm of genes associated with lipid metabolism in mice liver. Male C57BL/6 mice were randomly assigned to ambient PM₂.₅ or filtered air for 10 weeks via a whole body exposure system. We found that the liver mass was reduced significantly at zeitgeber time (ZT) 8 in mice exposed to PM₂.₅ but not levels or circadian rhythm of hepatic triglycerides or free fatty acid (FFA). In addition, exposure to PM₂.₅ led to enhanced expression of bmal1 at ZT0/24, cry1 at ZT16 and rev-erbα at ZT4 and ZT8. Furthermore, the expression of pparα was enhanced in mice liver at ZT4 and ZT8 after PM₂.₅ exposure, with upregulation of pparα-mediated genes responsible for fatty acid transport and oxidation. Finally, the expression of rate-limiting enzymes for lipid synthesis was all significantly increased in the liver of PM₂.₅ exposed mice at ZT12. Therefore, the present study provides new perspectives for revealing the etiology of hepatic lipid metabolism abnormality from PM₂.₅-induced circadian rhythm disorder.