Mining activity may cause heavy metal accumulation, which threatens human and animal health by their long-term persistence in the environment. This study aims to assess the impact of polymetallic pollution on chicken (Gallus domesticus) from old lead mining sites in northeast of Tunisia: Jebel Ressas (JR). Samples of soil and chickens were collected from five sites being ranked along a gradient of heavy metal contamination. Heavy metal loads were evaluated in soil samples and in chicken liver and kidney. Biochemical evaluation of oxidative stress parameters termed as Catalase (CAT), Glutathione-S-Transferase (GST), and Malondialdehydes (MDA) accumulation was monitored. Metallothionein protein level was assessed as a specific response to heavy metals. DNA alteration was achieved using MNi frequency in the investigated tissues. Finally, the evaluation of gene expression levels of CAT, GST, mt1, mt4, P53, bcl2, caspase3 and DNA-ligase was performed. Our data showed the highest loads of Cd, Cu, Zn and Pb in tissues of animals from site 3, being more pronounced in kidney. Biochemical data suggested a significant increase in antioxidant enzymes activities in all sites respect to control except in site 3 were CAT and GST were inhibited. DNA alteration was observed in all tissues being very pronounced in animals from site 3. Overall, transcriptomic data showed that genes involved in apoptosis were up-regulated in animals exposed to the most contaminated soils. Our data suggest that chicken and selected biomarkers offer a suitable model for biomonitoring assessment of heavy metals transfer through the food web in mining sites. Finally, the obtained results of heavy metals accumulation and related alterations should be carefully considered in view of the controversial relationship between distribution and toxicology of contaminants in exposed organisms.

Estuaries are often considered to be the filters of pollutants from the land-derived outflows of freshwater to open seawater. Oysters are efficient bioaccumulators of metals in the estuarine environment, however, little information is available on the long-term tissue variability of metals in a large dynamic estuary under complex urbanized and anthropogenic impacts. Thus, an eight-year biomonitoring study of metals (Ag, Cd, Cr, Cu, Ni, Pb, and Zn) in the oysters from 10 sites were carried out to reveal the highly spatial-temporal variations in the Pearl River Estuary (PRE) of China during 2011–2018. Cd, Cu, and Zn in oysters were significantly correlated with the dissolved metals in seawater. Geographically, Ag, Cd, and Cr were higher in the western sites, and Cu, Ni, and Zn were higher in the eastern sites. High seasonal variations of Ag, Cu, and Zn were found in the wet season. The calculated annual change rates (vc) of Cd, Cu, Zn, Ag, Pb, Ni, and Cr in the oysters were −1.1, −45, −48, 0.338, −0.216, −2.2, and −2.8 μg/g/y, respectively. If such decreasing rates of vc (or natural logarithm rates v) were maintained, Cd, Cu, Zn, Pb, and Ni in oysters from PRE would be expected to recover to the national 50% concentrations in years 2022 (2024), 2045 (2079), 2073 (2110), 2021 (2023), and 2019 (2020), respectively. Long-term series observations of metals in organisms reflected the real bioavailability of metals, pollution status, and trends for environmental management and control in a large dynamic and contaminated estuary.

Soil contamination with cadmium (Cd) has become a serious problem, adversely affecting food safety and human health. Effective methods are urgently needed to alleviate toxicity of Cd in plants. In this study, a nine-week continuous pot experiments was conducted to explore the effectiveness of the different nano iron oxide (α-Fe₂O₃, γ-Fe₂O₃, Fe₃O₄) alone and combined with biochar in muskmelon grown on a Cd-contaminated soil. The antioxidant system, chlorophyll, soluble protein, other physiological indexes of muskmelon leaves and the distribution of Cd in matrix soil, leaves and fruit were detected. The results showed that Cd was readily absorbed by plants and caused oxidative stress on plants, while biochar, α-Fe₂O₃ nanoparticles (NPs) and their mixture group (BFe1 group) could significantly improve it. Specifically, the three treatments reduced the Cd content of the fruit by 19.51–78.86%, reduced the Cd content of leaves by 15.44–36.23% and 22.36–31.77% in weeks 3 and 5, respectively. For the activity of enzymes, three treatments decreased superoxide dismutase (SOD) activity and catalase (CAT) activity by 3.41–38.57% and 24.27–30.33% in week 7, respectively. So BFe1 group application immobilized Cd in soil and reduced Cd partitioning in the aboveground tissues. Overall the combination of biochar and α-Fe₂O₃ NPs can alleviate Cd toxicity in muskmelon and can protect human beings from Cd exposure.

Black-spotted frogs and bullfrogs from an e-waste polluted area were collected and examined for legacy and emerging organophosphorus flame retardants (PFRs) and plasticizers. Total concentrations of PFRs and plasticizers were 0.62–15 ng/g wet weight (ww) and 316–4904 ng/g ww in muscles, 2.2–59 ng/g ww and 127–5757 ng/g ww in eggs and gonads, and 1.2–15 ng/g ww and 51–1510 ng/g ww in oviducts, respectively. For muscle tissues, concentrations of ∑PFRs, triethyl phosphate, tris-(2-chloroethyl) phosphate, and tris-(chloro-2-propyl) phosphate were significantly higher in the males than females (p < 0.05). However, for reproductive tissues, eggs exhibited higher levels of those contaminants than gonads (p < 0.05). No significant sex difference in levels of plasticizers was observed in muscles. In contrast, levels for (2-ethylhexyl) phthalate, di-n-butyl phthalate, and di-iso-butyl phthalate in gonads were significantly higher than those in eggs (p < 0.05). Significantly negative linear correlations between maternal transfer ratios and log KOW were found in female frogs. Paternal transfer potentials were first significantly and positively correlated to log KOW (<6) and then decreased afterward in the males. These results indicated that parental transfer was answer for the sex-specific accumulation of PFRs and plasticizers in frogs.

On-road remote sensing technology measures the concentration ratios of pollutants over CO₂ in the exhaust plume in half a second when a vehicle passes by a measurement site, providing a rapid, non-intrusive and economic tool for vehicle emissions monitoring and control. A key assumption in such measurement is that the emission ratios are constant for a given plume. However, there is a lack of study on this assumption, whose validity could be affected by a number of factors, especially the engine operating conditions and turbulence. To guide the development of the next-generation remote sensing system, this study is conducted to investigate the effects of various factors on the emissions dispersion process in the vehicle near-wake region and their effects on remote sensing measurement. The emissions dispersion process is modelled using Large Eddy Simulation (LES). The studied factors include the height of the remote sensing beam, vehicle speed, acceleration and side wind. The results show that the measurable CO₂ and NO exhaust plumes are relatively short at 30 km/h cruising speed, indicating that a large percentage of remote sensing readings within the measurement duration (0.5 s) are below the sensor detection limit which would distort the derived emission ratio. In addition, the valid measurement region of NO/CO₂ emission ratio is even shorter than the measurable plume and is at the tailpipe height. The effect of vehicle speed (30–90 km/h) on the measurable plume length is insignificant. Under deceleration condition, the length of the valid NO/CO₂ measurement region is shorter than under cruising and acceleration conditions. Side winds from the far-tailpipe direction have a significant effect on remote sensing measurements. The implications of these findings are discussed and possible solutions to improve the accuracy of remote sensing measurement are proposed.

An increase in nutrient input may disturb the bacterioplankton communities in freshwater aquaculture ponds during the peak period of culture. Water samples were collected from ponds of three cultivated species. After the samples were filtered and total DNA was extracted, Illumina high-throughput sequencing was used to profile the spatiotemporal distributions in bacterioplankton communities, the belt diversity, and the influencing factors during this period of time. The results showed that Proteobacteria, Cyanobacteria, Bacteroidetes, and Actinobacteria were the dominant phyla. Biological differences in cultivated species were the main influencing factors that shaped bacterioplankton communities. Monthly variations and thermal stratification provided little and no contribution to bacterioplankton communities, respectively. CODmn, Chla, and TN were the most appropriate parameters to describe the environmental interpretation of bacterial ordinations, and CODmn was the predominant factor. In addition, the higher similarity between CODmn and Chla, shown by clustering analysis, indicated that the algae-bacteria symbiotic system may have an important role in material circulation in freshwater aquaculture pond water during the peak period of culture. The present study has helped to elucidate the biological characteristics of aquaculture tail water, and enriched the basic data provided by bacterioplankton studies.

Black carbon (BC) is a product of incomplete combustion of fossil fuels and vegetation. The compelling evidence has demonstrated that it has a close relationship with several respiratory and cardiovascular diseases. BC provides the reactive sites and surfaces to absorb various chemicals, such as polycyclic aromatic hydrocarbons (PAH). Naphthoquinone is a typical PAHs which was found in particulate matter (PM) and 1,4NQ-BC owned high oxidative potential and cytotoxicity. IL-33 is an alarmin which increases innate immunity through Th2 responses. It was reported that IL-33 was a potent inducer of pro-inflammatory cytokines, like IL-6. In our previous study, it was revealed that 1,4NQ-BC instilled intratracheally to mice could trigger the lung inflammation and stimulate the secretion of IL-33 in lung tissue. We found that IL-33 could induce inflammation in lung itself. When the macrophages were eliminated, the secretion of IL-33 was reduced and the pathological damage in the lung was relieved after exposure to 1,4NQ-BC. Both MAPK and PI3K/AKT signal pathways were involved in the process of IL-33 secretion and the lung inflammation induced by 1,4NQ-BC. The findings herein support the notion that after exposure to 1,4NQ-BC, the increased secretion of IL-33 was mainly derived from macrophages through both MAPK and PI3K/AKT signal pathways.

Pesticide exposure is regarded as a contributing factor to the high gross loss rates of managed colonies of Apis mellifera. Pesticides enter the hive through contaminated nectar and pollen carried by returning forager honey bees or placed in the hive by beekeepers when managing hive pests. We used an in vitro rearing method to characterize the effects of seven pesticides on developing brood subjected dietary exposure at worse-case environmental concentrations detected in wax and pollen. The pesticides tested included acaricides (amitraz, coumaphos, fluvalinate), insecticides (chlorpyrifos, imidacloprid), one fungicide (chlorothalonil), and one herbicide (glyphosate). The larvae were exposed chronically for six days of mimicking exposure during the entire larval feeding period, which is the worst possible scenario of larval exposure. Survival, duration of immature development, the weight of newly emerged adult, morphologies of the antenna and the hypopharyngeal gland, and gene expression were recorded. Survival of bees exposed to amitraz, coumaphos, fluvalinate, chlorpyrifos, and chlorothalonil was the most sensitive endpoint despite observed changes in many developmental and physiological parameters across the seven pesticides. Our findings suggest that pesticide exposure during larvae development may affect the survival and health of immature honey bees, thus contributing to overall colony stress or loss. Additionally, pesticide exposure altered gene expression of detoxification enzymes. However, the tested exposure scenario is unlikely to be representative of real-world conditions but emphasizes the importance of proper hive management to minimize pesticide contamination of the hive environment or simulates a future scenario of increased contamination.

Air pollution is one of the most important branches of environmental science as it affects human health, climate and ecosystems. Emissions of air pollutants from transport (vehicles and ships) in port cities strongly affect air quality at local scales, warranting for a combination of theoretical and experimental studies to identify pollution hotspots. The purpose of this paper is to provide a methodology for developing a hybrid emission inventory from transport sector for two port cities located respectively on the Northern Aegean islands of Chios and Lesvos. Emission inventories were constructed for the year 2014 based on top-down and bottom-up approaches. Official data from local authorities and survey results were used for the calculation of emissions. Traffic emissions were spatially allocated to the road network based on population data and hourly traffic counts, and distributed over time (on an hourly basis) with the use of local temporal coefficients.Regarding carbon monoxide road emissions, the highest quantities are mainly emitted by Passenger Cars (43%,32% in Chios and Lesvos respectively) while for PM₁₀ emissions, trucks have the largest share (66% in Chios and 86% in Lesvos). The pollutants that are emitted in greater quantities from the ships at the ports of Mytilene and Chios are NOₓ, followed by SO₂ and CO. Most of the ship emissions in the ports occur by the ships at berth, as they remain berthed for hours whereas maneuvering lasts 15–20 min. As for the daily contribution of the two transport sources to the pollution profile of Mytilene, road emissions are higher for almost all pollutants. However, the contribution of ship emissions is not negligible, especially during the touristic period when marine traffic increases and emissions close to the port area become more important than those from road transport.

CH₄ oxidation in landfill cover soils plays a significant role in mitigating CH₄ release to the atmosphere. Oxygen availability and the presence of co-contaminants are potentially important factors affecting CH₄ oxidation rate and the fate of CH₄-derived carbon. In this study, microbial populations that oxidize CH₄ and the subsequent conversion of CH₄-derived carbon into CO₂, soil organic C and biomass C were investigated in landfill cover soils at two O₂ tensions, i.e., O₂ concentrations of 21% (“sufficient”) and 2.5% (“limited”) with and without toluene. CH₄-derived carbon was primarily converted into CO₂ and soil organic C in the landfill cover soils, accounting for more than 80% of CH₄ oxidized. Under the O₂-sufficient condition, 52.9%–59.6% of CH₄-derived carbon was converted into CO₂ (CECO₂₋C), and 29.1%–39.3% was converted into soil organic C (CEₒᵣgₐₙᵢc₋C). A higher CEₒᵣgₐₙᵢc₋C and lower CECO₂₋C occurred in the O₂-limited environment, relative to the O₂-sufficient condition. With the addition of toluene, the carbon conversion efficiency of CH₄ into biomass C and organic C increased slightly, especially in the O₂-limited environment. A more complex microbial network was involved in CH₄ assimilation in the O₂-limited environment than under the O₂-sufficient condition. DNA-based stable isotope probing of the community with ¹³CH₄ revealed that Methylocaldum and Methylosarcina had a higher relative growth rate than other type I methanotrophs in the landfill cover soils, especially at the low O₂ concentration, while Methylosinus was more abundant in the treatment with both the high O₂ concentration and toluene. These results indicated that O₂-limited environments could prompt more CH₄-derived carbon to be deposited into soils in the form of biomass C and organic C, thereby enhancing the contribution of CH₄-derived carbon to soil community biomass and functionality of landfill cover soils (i.e. reduction of CO₂ emission).