Mercury (Hg) has a complex atmospheric transformation cycle and acts as a global pollutant. Size-specific particle bound mercury (PBM) was implemented in different functional (industrial, urban and suburban) areas in Shanghai, China. The total concentration of 13-staged PBM (rang of 0.01–18.0 μm) varied of 99.0–611 pg/m3, with an average value of 318 ± 144 pg/m3. The Gaoqiao petrochemical industry (GQPI) site showed the highest concentrations, whereas the suburban Shanghai Jiao Tong University (SJTU) displayed the lowest. The PBM in nucleation, accumulation and coarse modes were 7.63–96.7, 69.5–455, and 9.43–176 pg/m3, respectively, and the fractions of 0.56–1.00 and 0.32–0.56 μm were the two most abundant. Both OC and EC displayed unimodal distribution patterns (peak of 0.56–1.00 μm) at GQPI, while bimodal distributions were observed at urban and suburban sites. Statistically positive correlations between the overall PBM and the corresponding PM and carbonaceous compounds (r = 0.38–0.54, p < 0.01), indicating their similar origins and OC/EC enhanced gaseous mercury forming PBM. The gas–particle partition model predicted gaseous oxidized mercury (GOM) were 253 ± 133, 237 ± 122, and 257 ± 144 pg/m3 for GQPI, SAES and SJTU, respectively. The particle proportions of divalent mercury in the fraction of 0.32–1.00 μm were substantial (>80%), but smaller (<50%) for nucleation and coarse modes. The fraction of 9.90–18.00 μm occupied nearly 50% of the overall dry deposition fluxes of mercury. These finding highlight the emissions from different mercury and OC/EC origins, caused different size-specific distributions of PBM, which further affect their gas-particle partitioning and dry deposition of mercury species.

Bisphenols and triclosan (TCS) are widely used in consumer products. However, knowledge on human exposure to these anthropogenic chemicals has remained limited in China, especially for children. In this study, concentrations of seven bisphenols and TCS were determined in 283 urine samples collected from South China children aged between 3 and 11 years old. Bisphenol A (BPA), bisphenol S (BPS) and TCS were frequently detected in urine samples, with a detection rate of 93%, 89%, and 95%, respectively. Urinary concentrations of Σ7BPs (the sum concentrations of the seven bisphenols) ranged from 0.43 to 31.5 μg/L, with a median value of 0.91 μg/L, while TCS concentrations ranged from < limit of quantification to 21.9 μg/L (median: 0.21 μg/L). BPA was the predominant analogue (median: 0.35 μg/L), accounting for 49.8% of Σ7BPs. The urinary BPA concentrations in children from Guangzhou were significantly greater than those from Shenzhen. Correlation analysis suggested that multiple exposure sources to South China children likely existed for BPA, BPS, and TCS. Age, but not gender, was negatively associated with urinary residues of BPA and BPS (p < 0.05) and positively with TCS concentrations (p < 0.05). The estimated daily intake of Σ7BPs (23.9 ng/kg bw/day) or TCS (5.63 ng/kg bw/day) was below the tolerant reference dose of BPA, indicating no considerable health hazard to South China children.

At present, the majority of investigations concerning nanotoxicology in the nematode C. elegans address short-term effects. While this approach allows for the identification of uptake pathways, exposition and acute toxicity, nanoparticle-organism interactions that manifest later in the adult life of C. elegans are missed. Here we show that a microhabitat composed of liquid S-medium and live bacteria in microtiter wells prolongs C. elegans longevity and is optimally suited to monitor chronic eNP-effects over the entire life span (about 34 days) of the nematode. Silver (Ag) nanoparticles reduced C. elegans life span in concentrations ≥10 μg/mL, whereas nano ZnO and CeO₂ (1–160 μg/mL) had no effect on longevity. Monitoring of locomotion behaviors throughout the entire life span of C. elegans showed that Ag NPs accelerate the age-associated decline of swimming and increase of uncoordinated movements at concentrations of ≥10 μg/mL, whereas neuromuscular defects did not occur in response to ZnO and CeO₂ NPs. By means of a fluorescing reporter worm expressing tryptophan hydroxylase-1::DsRed Ag NP-induced behavioral defects were correlated to axonal protein aggregation and neurodegeneration in single serotonergic HSN as well as sensory ADF neurons. Notably, serotonergic ADF neurons represented a sensitive target for Ag NPs in comparison to GABAergic neurons that showed no signs of degeneration under the same conditions. We conclude that due to its analogy to the jellylike boom culture of C. elegans on microbe-rich rotting plant material liquid S-medium culture in spatially confined microtiter wells represents a relevant as well as practical tool for comparative identification of age-resolved nanoparticle effects and vulnerabilities in a significant target organism. Consistent with this, specifically middle-aged nematodes showed premature neuromuscular defects after Ag NP-exposure.

The widespread adoption of genetically modified, glyphosate-tolerant corn and soybean varieties in US crop production has led to a dramatic increase in glyphosate usage. Though present at or below regulatory limits currently set for human foodstuffs, the concentration of glyphosate in companion animal feed is currently unknown. In the present study, 18 commercial companion animal feeds from eight manufacturers were analyzed for glyphosate residues using ELISA. Every product contained detectable glyphosate residues in the range of 7.83 × 10¹–2.14 × 10³ μg kg⁻¹ dry weight, with the average and medians being 3.57 × 10² and 1.98 × 10² μg kg⁻¹ respectively. Three products were tested for within-bag variation and six were tested for lot to lot variation. Little within-bag variation was found, but the concentration of glyphosate varied by lot in half of the products tested. Glyphosate concentration was significantly correlated with crude fiber content, but not crude fat or crude protein. Average daily intakes by animals consuming feeds containing the median glyphosate concentration are estimated to result in exposures that are 0.68–2.5% of the Allowable Daily Intake (ADI) for humans in the US and EU, which are 1750 and 500 μg kg⁻¹ respectively. Consumption of the most contaminated feed, however, would result in exposure to 7.3% and 25% of the above ADIs, though the relevance of such an exposure to companion animals is currently unknown.Companion animal feeds contained 7.83 × 10¹–2.14 × 10³ μg kg⁻¹ glyphosate which is likely to result in pet exposure that is 4–12 times higher than that of humans on a per Kg basis.

The concentrations of Cd, Cr and Pb in soil samples and As, Cd, Cr and Pb in plant specimens were analyzed in an arid area in central Iran. Plants were categorized into desert-adapted (Haloxylon ammodendron, Atraphaxis spinosa and Artemisia persica) and non-desert species. It was found that the trace element (TE) accumulating potential of the desert species (Haloxylon ammodendron and Artemisia persica) with a mean value of 0.1 mg kg⁻¹ for Cd was significantly higher than that of the majority of the non-desert species with an average of 0.05 mg kg⁻¹. Artemisia also had a high As accumulating capability with a mean level of 0.8 mg kg⁻¹ in comparison with an average of 0.2 mg kg⁻¹ for most of the other plant species. The mean values of Cr and Pb in Haloxylon ammodendron and Artemisia persica were 5 and 3 mg kg⁻¹, respectively. Among the desert-adapted plants, Atraphaxis proved to be a species with high Cr and Pb accumulating potential, as well. The geoaccumulation index and the overall pollution scores indicated that the highest environmental risk was related to Cd. Different statistical analyses were used to study the spatial patterns of soil Cd and their connections with pollution sources. The variogram was estimated using a classical approach (weighted least squares) and was compared with that of the posterior summaries that resulted from the Bayesian technique, which lay within the 95% Bayesian credible quantile intervals (BIC) of posterior parameter distributions. The prediction of cadmium values at un-sampled locations was implemented by multi-Gaussian kriging and sequential Gaussian simulation methods. The prediction maps showed that the region most contaminated by Cd was the north-eastern part of the study area, which was linked to mining activities, while agricultural influence contributed less in this respect.

Benzene series (BTEX) pollutants which are generated by traffic can deposit (build-up) on urban road surfaces. When they are washed-off by stormwater runoff, BTEX are toxic to ecological and human health if the stormwater is reused. To understand the risk posed by BTEX, it is essential to have an in-depth investigation on BTEX build-up, one of the most important stormwater pollutant processes. This study analysed the relationship between BTEX build-up and BTEX build-up's influential factors. The outcomes confirmed an important role of climatic factors (particularly temperature) on influencing BTEX build-up. This has not been considered in previous stormwater studies although this has been widely focused in atmospheric pollution. BTEX build-up loads were generally higher and the variability was low in dry seasons with low temperature such as winter and spring. Additionally, the influence of temperature on BTEX build-up on urban road surfaces is more important in the case of larger particles (such as >75 μm) than smaller particles. The study also showed that petrol station areas have a potential to export stormwater runoff with high BTEX concentrations, compared to typical urban roads. This is particularly applicable in winter and spring. These outcomes can provide useful guidance to improving stormwater quality modelling approaches, especially relevant to estimation of BTEX concentrations in the stormwater.

Communities resident in urban areas located near active volcanoes can experience volcanic ash exposures during, and following, an eruption, in addition to sustained exposures to high concentrations of anthropogenic air pollutants (e.g., vehicle exhaust emissions). Inhalation of anthropogenic pollution is known to cause the onset of, or exacerbate, respiratory and cardiovascular diseases. It is further postulated similar exposure to volcanic ash can also affect such disease states. Understanding of the impact of combined exposure of volcanic ash and anthropogenic pollution to human health, however, remains limited.The aim of this study was to assess the biological impact of combined exposure to respirable volcanic ash (from Soufrière Hills volcano (SHV), Montserrat and Chaitén volcano (ChV), Chile; representing different magmatic compositions and eruption styles) and freshly-generated complete exhaust from a gasoline vehicle. A multicellular human lung model (an epithelial cell-layer composed of A549 alveolar type II-like cells complemented with human blood monocyte-derived macrophages and dendritic cells cultured at the air-liquid interface) was exposed to diluted exhaust (1:10) continuously for 6 h, followed by immediate exposure to the ash as a dry powder (0.54 ± 0.19 μg/cm2 and 0.39 ± 0.09 μg/cm2 for SHV and ChV ash, respectively). After an 18 h incubation, cells were exposed again for 6 h to diluted exhaust, and a final 18 h incubation (at 37 °C and 5% CO2). Cell cultures were then assessed for cytotoxic, oxidative stress and (pro-)inflammatory responses.Results indicate that, at all tested (sub-lethal) concentrations, co-exposures with both ash samples induced no significant expression of genes associated with oxidative stress (HMOX1, NQO1) or production of (pro-)inflammatory markers (IL-1β, IL-8, TNF-α) at the gene and protein levels. In summary, considering the employed experimental conditions, combined exposure of volcanic ash and gasoline vehicle exhaust has a limited short-term biological impact to an advanced lung cell in vitro model.

Although hexachlorobutadiene (HCBD) has been listed as a persistent organic pollutant (POP) under Annexes A and C of the Stockholm Convention, information about its unintentional production and emission is still very limited. We estimated the historical unintentional production and emission of HCBD during 1992–2016 in China based on aggregated activity data and emission functions. The unintentional production of HCBD increased from 60.8 (95% confidence interval, 38.2–88.5) MT/yr to 2871.5 (2234.2–3530.0) MT/yr during 1992–2016, representing an average annual growth rate of 17.4%. The main unintentional source of HCBD changed from carbon tetrachloride to trichloroethylene production during this period. We estimated that China's cumulative emissions of HCBD were 8211.3 (6131.5–10,579.5) MT during the same period. HCBD consumption and the chlorinated hydrocarbon production sector were the major contributors to total HCBD emissions. Owing to the long-range transport capability of HCBD (8784 km), such high emissions in China may cause adverse effects in other regions.

Di-2-ethylhexyl phthalate (DEHP) has been widely used as a plasticizer in industry. DEHP can cause testicular atrophy, yet the exact mechanism remains unclear. In this study, male mice were intragastrically (i.g.) administered with 0, 100, 200 or 400 mg DEHP/kg/day for 21 days. We found that DEHP caused disintegration of the germinal epithelium and decreased sperm density in the epididymis. Furthermore, there was a significant increase in the levels of cleaved Caspase-8, cleaved Caspase-3 and Bax proteins and a decrease in Bcl2 protein. The results indicated that DEHP could induce apoptosis of the testis tissue. Meanwhile, DEHP significantly induced autophagy in the testis tissues with increases in LC3-II, Atg5 and Beclin-1 proteins. The serum testosterone concentration decreased in the DEHP-treated group, implying that DEHP might lead to Leydig cell damage. Furthermore, oxidative stress was induced by DEHP in the testis. To further investigate the potential mechanism, mouse TM3 Leydig cells were treated with 0–80 μM DEHP for 48 h. DEHP significantly inhibited cell viability and induced cell apoptosis. Oxidative stress was involved in DEHP-induced apoptosis as N-Acetyl-L-cysteine (NAC), an inhibitor of oxidative stress, could rescue the inhibition of cell viability and induction of apoptosis by DEHP. Similar to the in vivo findings, DEHP could also induce cell autophagy. However, inhibition of autophagy by 3-Methyladenine (3-MA) significantly increased cell viability and inhibited apoptosis. Taken together, oxidative stress was involved in DEHP-induced apoptosis and autophagy of mouse TM3 Leydig cells, and autophagy might play a cytotoxic role in DEHP-induced cell apoptosis.

The clean-up effort that is occurring across the region affected by the 2011 Fukushima Daiichi Nuclear Power Plant accident is unprecedented in its magnitude as well as the financial cost that will eventually result. A major component of this remediation is the stripping of large volumes of material from the land surface, depositing this into large waste storage bags before placing these 1 cubic meter bags into specially constructed stores across Fukushima Prefecture.In this work, using an unmanned aerial vehicle to perform radiological surveys of a site, the time-resolved distribution of contamination during the construction of one of these waste storage sites was assessed. The results indicated that radioactive material was progressively leaching from the store into the surrounding environment. A subsequent survey of the site conducted eight months later revealed that in response to this survey and remedial actions, the contamination issue once existing on this site had been successfully resolved. Such results highlight the potential of low-altitude unmanned aerial systems to easily and rapidly assess site-wide changes over time – providing highly-visual results; therefore, permitting for prompt remedial actions to be undertaken as required.Use of UAV radiation mapping and airborne photogrammetry to produce a time-resolved assessment of remediation efforts within a Fukushima temporary storage facility.