Carcinogenic and neurotoxic polybrominated diphenyl ethers (PBDEs) are environmentally ubiquitous and have been widely investigated. However, little is understood regarding their pollution status, sources, and potential risk to persons in public transportation microenvironments (PTMs). We collected 60 dust samples from PTMs and then selected four materials typical of bus interiors to determine the sources of PBDEs in dust using principal component analysis coupled with Mantel tests. We then evaluated the risk of PBDEs to public health using Monte Carlo simulations. We found that PBDE concentrations in dust were 2-fold higher in buses than at bus stops and that brominated diphenyl ether (BDE)-209 was the main pollutant. The number of buses that passed through a bust stop contributed to the extent of PBDE pollution, and the primary potential sources of PBDEs in dust were plastic handles and curtains inside buses; BDE-209 and BDE-154 were the main contributors of pollution. We found that health risk was 8-fold higher in toddlers than in adults and that the reference doses of PBDEs in dust were far below the United States Environmental Protection Agency limits. Our findings provide a scientific basis that may aid in preventing PBDE pollution and guiding related pollution management strategies in PTMs.

Straw and biochar amendments have been shown to increase soil organic carbon (SOC) stocks in arable land; however, their effects on hydrological fluxes of dissolved organic carbon (DOC), which may offset the benefits of C sequestration amounts remain uncertain. Therefore, we conducted a three-year field study that included four treatments (CK, control with no fertilizer; NPK, synthetic N fertilizer; RSDNPK, synthetic N fertilizer plus crop residues; BCNPK, synthetic N fertilizer plus biochar of crop straw) to investigate the effects of straw and biochar amendment on DOC losses through hydrological pathways of overland flow and interflow from a wheat-maize rotation system in the subtropical montane agricultural landscape. We detected substantial intra- and inter-annual variations in runoff discharge, DOC concentration, and DOC fluxes for both overland flow and interflow pathways, which were primarily attributed to variations in rainfall amount and intensity. On average, the DOC concentrations for interflow (2.98 mg C L⁻¹) were comparable with those for overland flow (2.71 mg C L⁻¹) throughout the three-year experiment. However, average annual DOC fluxes for interflow were approximately 2.60 times greater than those for overland flow, which probably related to higher runoff discharges of interflow than overland flow. Compared to the control, on average, the N fertilization treatments significantly decreased the annual DOC fluxes of overland flow and significantly increased annual DOC fluxes of interflow. Relative to the application of synthetic N fertilizer only, on average, crop straw amendment practice significantly increased annual DOC fluxes of interflow by 28.7%, while decreasing annual DOC fluxes of overland flow by 12.0%; in contrast, biochar amendment practice decreased annual DOC fluxes of interflow by 25.3% while increasing annual DOC fluxes of overland flow by 44.6%. Overall, considering both overland flow and interflow, crop straw amendment significantly increased hydrological DOC fluxes, whereas biochar had no significant effects on hydrological DOC fluxes throughout the three-year experiment. We conclude that crop straw incorporation strategies that aim to increase SOC stocks may enhance hydrological losses of DOC, thereby in turn offsetting its benefits in the subtropical montane agricultural landscapes.

Urban green spaces (UGSs) are often positively associated with the health of urban residents. However, UGSs may also have adverse health effects by releasing biogenic volatile organic compounds (BVOCs) and increasing the ambient concentrations of ozone (O₃) and secondary organic aerosols in urban areas. BVOC emissions from UGSs might be underestimated because of the lack of consideration of the UGS land-use type in urban areas. As such, in this study, we used a newly released satellite dataset, Sentinel-2, with a resolution of 10 m, to derive the classification distribution of UGSs and predict the UGS emissions of BVOCs in Beijing in 2019. The results showed that the annual emissions of BVOCs from UGSs were approximately 2.9 Gg C (95% confidence interval (CI): 2.4–3.3) in the six core districts, accounting for approximately 39% of the total UGS emissions in Beijing. Compared with the results based on Sentinel-2, the BVOC emissions might be underestimated by approximately 37% (95% CI: 11–63) using the commonly used satellite dataset. UGSs produced the highest BVOC emissions in summer (from June to August), accounting for 75.2% of the annual emissions. UGSs contributed the most to the O₃ formation potential in summer, accounting for 41.5% of the total. We could attribute a considerable amount of the O₃ concentration (27.0 μg m⁻³, 95% CI: 21.4–32.6) to the UGS BVOCs produced in the core districts of Beijing in July. The new BVOC emissions dataset based on Sentinel-2 vegetation information facilitates modeling studies on the formation of surface O₃ in urban areas and assessments of the impact of UGSs on public health.

Novel magnetic microcomposites consisting of graphene oxide and iron oxide was synthesized to immobilize metabolically versatile Paracoccus sp. MKU1 and Leucobacter sp. AA7 and tested for the simultaneous adsorption and enhanced biological detoxification of hexavalent chromium (Cr(VI)) from tannery wastewater. This study reports highest chromium adsorption of 272.6 mg/g and 179.3 mg/g with complete reduction of Cr(VI) to Cr(III) by the microcomposites of AA7 and MKU1 from wastewater in a bioreactor (10 L) at large-scale for first time in ex situ. Furthermore, both the microcomposites displayed an enhanced detoxification of tannery wastewater by reducing various physicochemical conditions such as ammonia, nitrate, TDS, fluoride, CaCO₃, Ca, Mg, NO₃ and SO₂ under the permissible limits. Use of electromagnetic device for magnetic microcomposites recovery from bioreactor yielded a maximum of 88% and 80.6% recovery for AA7 and MKU1, respectively. The rate of chromium recuperation achieved following desorption from the microcomposites of AA7 and MKU1 was 90.71% and 93.97%, respectively. Thus, the multifarious benefits including adsorption, metabolic detoxification, recovery, and recuperation by single functional microcomposites seems to be an intriguing and profitable approach for practicing in real-time operations to effectively remove heavy metals from the contaminated wastewater for environmental protection.

We investigated the competitive effects of different fractions of wastewater treatment plant effluent organic matter (EfOM) on adsorption of an organic micro pollutant (OMP), propranolol (PRO), in a fixed bed column packed with magnetic tyre char (MTC). The results showed that the presence of EfOM inhibited PRO adsorption in wastewater leading to decreased PRO adsorption capacity from 5.86 to 2.03 mg/g due to competitive effects and pore blockage by smaller EfOM fractions. Characterization of EfOM using size exclusion chromatography (LC-OCD) showed that the principal factor controlling EfOM adsorption was pore size distribution. Low molecular weight neutrals had the highest adsorption onto MTC while humic substances were the least interfering fraction. Effect of important parameters such as contact time, linear velocity and bed height/diameter ratio on MTC performance was studied in large-lab scale columns. Linear velocity and contact time were found to be effective in increasing adsorption capacity of PRO on MTC and delaying breakthrough time. Increase in linear velocity from 0.64 cm/min to 1.29 cm/min increased mass transfer and dispersion, resulting in considerable rise of adsorbed amount (5.86 mg/g to 22.58 mg/g) and increase in breakthrough time (15.8–62.7 h). Efficiency of non-equilibrium Hydrus model considering dispersion and mass transfer mechanism was demonstrated for real wastewater and scale up purposes. Ball milling for degradation of adsorbed PRO and regeneration of MTC resulted in 79% degradation of PRO was achieved after 5 h milling (550 rpm), while the addition of quartz sand increased the efficiency to 92%.

Testicular junctions are pivotal to male fertility and regulated by constituent proteins. Increasing evidence suggests that environmental chemicals, including bisphenol A (BPA), may impact these proteins, but whether the impacts persist for generations is not yet known. Here, we investigate the effect of BPA (a ubiquitous endocrine-disrupting chemical) on testis and sperm functions and whether the effects are transferred to subsequent generations. Male mice (F0) were exposed to corn oil (Control) or 5 or 50 mg BPA/kg body weight/day from 6 to 12 weeks of age. The F0 were mated with wild-type females to produce the first filial (F1) generation. F2 and F3 were produced using similar procedures. Our results showed that BPA doses decreased the levels of some junctional proteins partly via binding with estrogen receptors (ERα and Erβ), upregulation of p-ERK1/2, P85, p-JNK and activation of p38 mitogen-activated protein kinase signaling. Consequently, testicular histological abnormalities, disrupted spermatogenesis, decreased sperm count, and inability to fertilize eggs were observed in mice exposed to BPA. These effects were transferred to successive generations (F2), partly through DNA methylation, but mostly alleviated in F3 males. Our findings suggest that paternal exposure to chemicals promoting alteration of testicular junctional proteins and its transgenerational inheritance is a key component of the origin of male reproductive health problems.

Accelerating evidence of endocrine-related morbidity has raised alarm about the ubiquitous use of phthalates in the human environment, but studies have not directly evaluated mortality in relation to these exposures. To evaluate associations of phthalate exposure with mortality, and quantify attributable mortality and lost economic productivity in 2013–4 among 55–64 year olds. This nationally representative cohort study included 5303 adults aged 20 years or older who participated in the US National Health and Nutrition Examination Survey 2001–2010 and provided urine samples for phthalate metabolite measurements. Participants were linked to mortality data from survey date through December 31, 2015. Data analyses were conducted in July 2020. Mortality from all causes, cardiovascular disease, and cancer. Multivariable models identified increased mortality in relation to high-molecular weight (HMW) phthalate metabolites, especially those of di-2-ethylhexylphthalate (DEHP). Hazard ratios (HR) for continuous HMW and DEHP metabolites were 1.14 (95% CI 1.06–1.23) and 1.10 (95% CI 1.03–1.19), respectively, with consistently higher mortality in the third tertile (1.48, 95% CI 1.19–1.86; and 1.42, 95% CI 1.13–1.78). Cardiovascular mortality was significantly increased in relation to a prominent DEHP metabolite, mono-(2-ethyl-5-oxohexyl)phthalate. Extrapolating to the population of 55–64 year old Americans, we identified 90,761–107,283 attributable deaths and $39.9–47.1 billion in lost economic productivity. In a nationally representative sample, phthalate exposures were associated with all-cause and cardiovascular mortality, with societal costs approximating $39 billion/year or more. While further studies are needed to corroborate observations and identify mechanisms, regulatory action is urgently needed.

Deciphering the potential mechanism of chemical-induced toxicity enables us to alleviate the cellular and organismal dysfunction. The environmental presence of nonylphenol (endocrine disruptor) has a major health concern due to its widespread usage in our day-to-day life. The current study establishes a novel functional link among nonylphenol-induced oxidative stress, Heat shock protein 27 (Hsp27, member of stress protein family), and Ecdysone receptor (EcR, a nuclear receptor), which eventually coordinates the nonylphenol-induced sub-cellular and organismal level toxicity in a genetically tractable model Drosophila melanogaster. Drosophila larvae exposed to nonylphenol (0.05, 0.5 and 5.0 μg/mL) showed a significant decrease in Hsp27 and EcR mRNA levels in the midgut. In concurrence, reactive oxygen species (ROS) levels were increased with a corresponding decline in glutathione (GSH) level and Thioredoxin reductase (TrxR) activity. Increased lipid peroxidation (LPO), protein carbonyl (PC) contents, and cell death were also observed in a correlation with the nonylphenol concentrations. Sub-cellular toxicity poses a negative organismal response, which was evident by delayed larval development and reduced Drosophila emergence. Subsequently, a positive genetic correlation (p < 0.001) between EcR and Hsp27 revealed that nonylphenol-dependent EcR reduction is a possible link for the downregulation of Hsp27. Further, Hsp27 overexpression in midgut cells showed a reduction in nonylphenol-induced intracellular ROS, LPO, PC content, and cell death through the TrxR mediated regenerative pathway and reduced GSH level improving the organismal response to the nonylphenol exposure. Altogether, the study elucidates the potential EcR-Hsp27 molecular interactions in mitigating the nonylphenol-induced cellular and organismal toxicity.

Increasing levels of artificial light at night (ALAN) are a major threat to global biodiversity and can have negative impacts on a wide variety of organisms and their ecosystems. Nocturnal species such as bats are highly vulnerable to the detrimental effects of ALAN. A variety of lighting management strategies have been adopted to minimise the impacts of ALAN on wildlife, however relatively little is known about their effectiveness. Using an experimental approach, we provide the first evidence of negative impacts of part-night lighting (PNL) strategies on bats. Feeding activity of Myotis spp. was reduced along rivers exposed to PNL despite no reduction in overall bat activity. We also provide the first evidence of negative effects of PNL on both feeding and activity for Pipistrellus pipistrellus which has previously been recorded feeding under artificial light. Despite having considerable energy-saving benefits, we outline the potential negative impacts of PNL schemes for bats in riparian habitats. PNL are unlikely to provide desired conservation outcomes for bats, and can potentially fragment important foraging habitats leading to a breakdown of functional connectivity across the landscape. We highlight the potential dichotomy for strategies which attempt to simultaneously address climate change and biodiversity loss and recommend alternative management strategies to limit the impacts of ALAN on biodiversity.

The contamination of paddy soils is of great concern since it links to human health via food supply. Limited knowledge is available on PCB residue characteristics and the associated health risks in paddy soils under various environmental conditions. In this study, a soil sampling campaign was conducted in three typical paddy fields, i.e., Sanjiang Plain (SP), Taihu Plain (TP) and Hani Terrace (HT), crossing a transect of 4000 km in China. The concentrations of 29 quantified PCBs varied from 58.6 to 1930 pg/g in paddy soils, with samples at TP showing the highest burden. Tri-CBs were the major homologue group at SP and HT, whereas hexa-CBs at TP. Altitude, temperature, soil organic matter content and soil conductivity well explained the variations in PCB concentrations among sites. The homologue profiles of soil PCBs followed the fractionation theory. In addition, soil conductivity was found to be negatively correlated to low-chlorinated PCBs and positively to high-chlorinated congeners. Furthermore, the toxicities of soil PCBs and the exposure risks through rice intake were estimated. Higher toxicity equivalent quantities and hazard indexes were found at SP than TP and HT, with over one third of the samples displaying health risks. The results of this work highlight the necessity to better understand the occurrence characteristics and the associated health risks of PCBs in soils of rice-growing regions.