The combined contamination of brominated flame retardants (BFRs) and heavy metals in electronic waste (e-waste) recycling and disposal areas has been a serious concern owing to their environmental persistence and chronic toxicities. Ammonia oxidizers, e.g., ammonia-oxidizing archaea (AOA) and bacteria (AOB) play essential roles in nitrogen cycling and can serve as ideal indicators that reflect the changes in sediment health in response to environmental variables. There is currently very little information available on the combined toxic effects of BFRs and heavy metals on AOA and AOB communities. In this study, two typical e-waste pollutants, tetrabromobisphenol A (TBBPA) and copper (Cu), were selected as target contaminants to investigate the individual and combined effects of both pollutants on AOA and AOB communities in river sediments. Respective treatments of TBBPA (1, 10, and 20 mg/kg wet weight), Cu (100 mg/kg wet weight) and their combined treatments (weight ratios of 1:100, 1:10, and 1:5) were performed in laboratory experiments. High-throughput sequencing was applied to explore the response of ammonia oxidizers to TBBPA and Cu. The interaction types of TBBPA and Cu were calculated by the directional classification system to reveal the individual and combined toxicities of both contaminants to the ammonia oxidizers. On days 15 and 30, the dominant interaction type of TBBPA and Cu was synergistic (62.50%), and the combined contamination exacted selective pressure and inhibition on the AOB and AOA communities. On days 45 and 90, the interaction type shifted to be antagonistic (83.33%), with both the AOB and AOA communities gradually reaching stable population equilibria. The alteration of the interaction type is attributed to the elevated TBBPA/Cu tolerance as the incubation time increased. This study disclosed the interaction types of TBBPA and Cu in contaminated river sediments, and revealed that the combined effect could potentially manipulate AOB and AOA communities.

The fate of veterinary antibiotics (VAs) in soil environment is determined by the hydrophilic performance and solubility of VAs and the type of soil. In this study, sulfadiazine (SDZ) and chlortetracycline (CTC) were selected as target pollutants, and a batch sorption method was used to find out the single and sorption competitive behavior and mechanism of the target pollutants on loess soil. Kinetic studies showed the apparent sorption equilibrium was reached 0–6 h for CTC and 0–12 h for SDZ. The sorption kinetics of VAs on loess soil were fitted well with a pseudo-second order kinetic model. Sorption thermodynamic data indicated the isotherm sorption of both SDZ and CTC on loess soil was fitted well with Freundlich isothermal (R², 0.960–0.975) and linear models (R², 0.908–0.976). The sorption affinity of CTC (Kd, 290–1620 L/kg for CTC) was much greater than that of SDZ (Kd, 0.6–4.9 L/kg for SDZ). The results also suggest that SDZ may be easily mobilized or leached from loess soil at neutral and alkaline pH, while CTC may be easily mobilized or leached at neutral pH. The sorption of each single target pollutant on the outer layer complex decreased with increasing ionic strength. Higher initial concentrations resulted in greater sorption capacity of target pollutants on loess soil increased. The sorption capacities of CTC and SDZ in the mixed system were lower than the sorption capacity of each single system, showing a competitive sorption behavior of CTC and SDZ during the sorption process. Overall, CTC showed the highest sorption potential in loess soil, whereas SDZ showed a high leaching risk in loess soil. These findings contribute to understanding the fate of different VAs in loess in the natural environment.

Multiple types of persistent organic pollutants (POPs), such as polychlorinated biphenyls (PCBs), polychlorinated naphthalenes (PCNs), and hexachlorobenzene (HCB), can be unintentionally released from combustion or thermal industrial processes, which are speculated to be the main sources of these contaminants, as they were banned on production and use since several decades ago. In this study, concentrations and sources of 40 PCBs, 39 PCNs, and HCB were analyzed in air samples collected during the period 2012–2015 at a background site in east China. ΣPCBs, ΣPCNs, and HCB were in the range of 9–341 pg/m³, 6–143 pg/m³, and 14–522 pg/m³, respectively. Seasonal characteristics with high levels in winter and low levels in summer were observed for PCNs and HCB. PCBs also exhibited slightly higher levels in winter. Source apportionment was conducted, using polycyclic aromatic hydrocarbons (PAHs) as combustion sources indicator, combined with principal component analysis (PCA) and positive matrix factorization (PMF) model. The results indicated that the legacy of past produced and used commercial PCBs was the dominant contributor (∼56%) to the selected PCBs in the atmosphere in east China. PCNs were mainly emitted from combustion sources (∼64%), whereas HCB almost entirely originated from combustion process (>90%).

Chromium has been proven to be extremely phytotoxic. This study explored the impacts of increasing Cr(VI) exposure (up to 10 mg L⁻¹ K₂Cr₂O₇) on the growth and development of alfalfa plants and adaptation responses employed, in an environmentally relevant context. The threshold concentration of K₂Cr₂O₇ in irrigation water beyond which stress responses are initiated is 1 mg L⁻¹. Lower Cr(VI) exposure (0.5 mg L⁻¹ K₂Cr₂O₇) induced hormesis, evident through increased biomass and larger leaves, likely mediated by increased NO content (supported by elevated NR enzymatic activity and overexpression of NR and ndh genes). Elevated Cr(VI) exposure (5 and 10 mg L⁻¹ K₂Cr₂O₇) resulted in reduced biomass and smaller leaves, and lower levels of photosynthetic pigment (10 mg L⁻¹ K₂Cr₂O₇). Higher levels of lipid peroxidation, H₂O₂ and NO contents in these plants suggested nitro-oxidative stress. Stress responses included increased SOD and CAT enzymatic activities, further supported to some extent by MnSOD, FeSOD, Cu/ZnSOD and CAT transcripts levels. GST7 and GST17 gene expression patterns, as well as proline content, P5CS enzymatic activity and corresponding P5CS and P5CR gene expression levels emphasized the role of proline and GSTs in the adaptation responses. Results highlight the importance of managing Cr(VI) levels in irrigation water.

Microbiota associated with airborne particulate matter (PM) is an important indicator of indoor pollution as they can be pathogenic and cause serious health threats to the exposed occupants. Present study aimed to investigate the level of culturable microbes associated with PM and their toxicological characterization in urban and rural houses of Pune city. Highest concentration of bacterial aerosols observed to be associated with PM₁₀ size fraction in urban site (2136 ± 285 CFU/m³) whereas maximum fungal concentration has been measured in rural houses (1521 ± 302 CFU/m³). Predominantly found bacterial species were Bacillus sp., S. aureus, and Pseudomonas aeruginosa and fungal species were Aspergillus sp., Cladosporium sp., and Penicillium sp. in both urban and rural residential premises. Concentration of endotoxin measured using the kinetic Limulus Amebocyte Lysate assay exhibited that the level of endotoxin in both urban and rural sites are associated with household characteristics and the activities performed in indoor as well as outdoor. Cell free DTT assay confirmed the ability of these airborne microbes to induce the production of reactive oxygen species (ROS) varying along with the types of microorganisms. On exposure of A549 cells to airborne microbes, a significant decrease in cell viability was observed in terms of both necrosis and apoptosis pathway. Elevated production of nitric oxide (NO) and proinflammatory cytokines in epithelial cells and macrophages clearly suggest the inflammatory nature of these airborne microbes. Results derived from the present study demonstrated that the indoor air of urban and rural houses of Pune is contaminated in terms of microbial load. Therefore, attention should be paid to control the factors favoring the microbial growth in order to safeguard the health of exposed inhabitants.

Evidence suggests that residential greenness may be protective of high blood pressure, but there is scarcity of evidence on the associations between greenness around schools and blood pressure among children. We aimed to investigate this association in China. Our study included 9354 children from 62 schools in the Seven Northeastern Cities Study. Greenness around each child’s school was measured by NDVI (Normalized Difference Vegetation Index) and SAVI (Soil-Adjusted Vegetation Index). Particulate matter ≤ 1 μm (PM1) concentrations were estimated by spatiotemporal models and nitrogen dioxide (NO2) concentrations were collected from air monitoring stations. Associations between greenness and blood pressure were determined by generalized linear and logistic mixed-effect models. Mediation by air pollution was assessed using mediation analysis. Higher greenness was consistently associated with lower blood pressure. An increase of 0.1 in NDVI corresponded to a reduction in SBP of 1.39 mmHg (95% CI: 1.86, −0.93) and lower odds of hypertension (OR = 0.76, 95% CI: 0.69, 0.82). Stronger associations were observed in children with higher BMI. Ambient PM1 and NO2 mediated 33.0% and 10.9% of the association between greenness and SBP, respectively. In summary, greater greenness near schools had a beneficial effect on blood pressure, particularly in overweight or obese children in China. The associations might be partially mediated by air pollution. These results might have implications for policy makers to incorporate more green space for both aesthetic and health benefits.

In this work, three gastropods Patella vulgata, Osilinus turbinata, and Tahis clavigera, one echinoderm Parancetrotus lividus, one coelenterate Anemonia sulcata, and two seaweed Padina pavonica, and Cystoseira mediterranea were collected from three different marine areas of Sardinia in the Mediterranean sea and studied for heavy metals and metalloid content and accumulation trends.Inductively coupled plasma optical emission spectrometry (ICP-OES) was used for the determination of Al, AS, B, Ba, Be, Cd, Co, Cr, Cu, Fe, Hg, Mn, Mo, Ni, Pb, Sb, Se, Sn, Sr, Te, Ti, V and Zn in the selected samples. The results showed that gastropods were capable of accumulating Al, Ba, Cu, Fe, Sr, and Zn; seaweeds can better concentrate Al, Fe, and Zn than all other species. At the same time, echinoderms and coelenterate had limited ability to store specific metals, showing a much more homogeneous distribution. PCA analysis allowed us to discriminate among the sites and the species. Cala Zafferano was the area with the higher values of accumulation of all metals in all species as expected, considering its proximity to industrial sites. The results of the analysis showed clearly that heavy metal and metalloid accumulation was different for each species studied. Therefore, for a correct environmental assessment of a given area, a comprehensive approach is strongly recommended by exploiting the different properties of both accumulation and concentration of the metals by different aquatic species.

Forests in Mediterranean Europe including Portugal are highly susceptible to wildfires. Freshwaters are often exposed to post-wildfire contamination that contains several toxic substances, which may impose risk to freshwater organisms and ecosystem functions. However, knowledge on the impacts of post-wildfire runoffs from different origins on freshwater biota is scarce. In forest streams, invertebrate shredders have a major contribution to aquatic detrital-based food webs, by translocating energy and nutrients from plant-litter to higher trophic levels. We investigated the leaf consumption behaviour and the responses of oxidative and neuronal stress enzymatic biomarkers in the freshwater invertebrate shredder Allogamus ligonifer after short-term exposure (96 h) to post-wildfire runoff samples from Pinus and Eucalyptus plantation forests and stream water from a burnt catchment in Portugal. Chemical analyses indicated the presence of various metals and PAHs at considerable concentrations in all samples, although the levels were higher in the runoff samples from forests than in the stream water. The shredding activity was severely inhibited by exposure to increased concentrations of post-wildfire runoff samples from both forests. The dose-response patterns of enzymatic biomarkers suggest oxidative and neuronal stress in the shredders upon exposure to increasing concentrations of post-wildfire runoffs. The impacts were more pronounced for the runoffs from the burnt forests. Moreover, the response patterns suggest that the energy from the feeding activity of shredders might have contributed to alleviate the stress in A. ligonifer. Overall, the outcomes suggest that the post-wildfire contamination can induce sublethal effects on invertebrate shredders with impacts on key ecological processes in streams.

Bird guano and the faeces of marine mammals appear to be a significant yet undisclosed biotransporter of Endocrine Disrupting Compounds in the marine environment. The authors determined the concentration of bisphenol A (BPA), 4-tert-octylphenol (4-t-OP) and 4-nonylphenol (4-NP) removed from birds and seals in their droppings into the coastal zone of the Gulf of Gdansk (Southern Baltic Sea).The research was carried out on samples of bird guano collected during the breeding season and after in 2016 at nesting sites, as well as on faecal samples from grey seals (Halichoerus grypus grypus) living in the Seal Centre of the Marine Station in Hel between 2014 and 2018. Measurements were carried out using high performance chromatography with fluorescence detector. Results have shown that the presence of seabird habitats and grey seal colonies in the coastal zone of the Gulf of Gdansk can have an impact on the pollution of the seashore (beach sand, bottom sediment and surface seawater) with phenol derivatives. The concentrations of BPA, 4-t-OP and 4-NP ranged from 0.1 to 32.97 ng∙g⁻¹dw in sediment and beach sand, and from 0.23 to over 800 ng dm⁻³ in seawater. In the cases of bisphenol A and 4-tert-octylphenol safe concentration levels in the waters were exceeded. Bisphenol A concentrations were almost always found to be the highest. This was also noted in bird guano and seal faeces, although it was found to be much higher in the seal faeces - average 10149.79 ng g⁻¹ dw, than in bird guano. An experiment conducted to assess BPA, 4-t-OP, 4-NP leaching from bird guano and seal faeces into seawater, also confirmed the importance of animal excrement in the circulation of these compounds in the marine ecosystem. The highest % of leaching related to BPA was noted at 20 °C and reached 84%. The lowest % of leaching was for 4-nonylphenol (44%).

Litter is omnipresent in the ocean where it can be ingested by marine biota. Although ingestion of microplastics (MPs) is abundantly reported, insights into how MP can influence predator-prey interactions currently limits our understanding of the ecological impact of MPs. Here we demonstrate trophic transfer of MPs from zooplankton to benthic filter feeders, through consumption of contaminated prey (i.e. prey with ingested MP). However, predation rates of contaminated prey were significantly lower as compared to predation rates of prey that had no MPs ingested. As filter feeder clearance rates were not affected by consumption of MPs, the lower predation rates of contaminated prey appear to be primarily explained by disruption in zooplankton swimming behaviour that reduces their filtration risk. This is the first study that shows how MPs can change predator-prey interactions that are involved in the coupling between the pelagic and seabed habitat.