Cytochrome P450 1A2 (CYP1A2) is an enzyme involved in the metabolic activation of certain carcinogens, and inducible by toxic substrates. To date, few studies have investigated in vivo CYP1A2 induction in humans and its relationship to polycylic aromatic hydrocarbons (PAHs) like benzo(a)pyrene (BaP). Non-smoking healthy male coke-oven workers (n = 30) were recruited as ‘exposure’ group, and non-smoking healthy office workers in the same city (n = 10) were selected as ‘control’ group, to test whether high inhalation exposure to PAHs can induce CYP1A2 activity in human livers. Significantly higher inhalation exposure of PAHs were found among the exposure group compared to the control. Inhalation BaP exposure concentration in the exposure group was more than 30 times higher than the control group (p < 0.001). However, the exposure group did not exhale significant higher levels of ¹³CO2/¹²CO2 in breath samples (p = 0.81), and no significant relationship was found between the inhaled BaP concentration and the ¹³CO2/¹²CO2 ratio (p = 0.91). A significant association was found between the ¹³CO2/¹²CO2 exhalation and dietary BaP intake level. Hepatic CYP1A2 activity/induction level was not effected by inhaled BaP but was altered by ingestion of BaP.

Mangroves are complex and dynamic ecosystems highly dependent on diverse microbial activities. In the last decades, these ecosystems have been exposed to and affected by diverse human activities, such as waste disposal and accidental oil spills. Complex microbial communities inhabiting the soil and sediment of mangroves comprise microorganisms that have developed mechanisms to adapt to organic and inorganic contaminants. The resistance of these microbes to contaminants is an attractive property and also the reason why soil and sediment living microorganisms and their enzymes have been considered promising for environmental detoxification. The aim of the present study was to identify active microbial genes in heavy metals, i.e., Cu, Zn, Cd, Pb and Hg, and antibiotic resistomes of polluted and pristine mangrove sediments through the comparative analysis of metatranscriptome data. The concentration of the heavy metals Zn, Cr, Pb, Cu, Ni, Cd, and Hg and abundance of genes and transcripts involved in resistance to toxic compounds (the cobalt-zinc-cadmium resistance protein complex; the cobalt-zinc-cadmium resistance protein CzcA and the cation efflux system protein CusA) have been closely associated with sites impacted with petroleum, sludge and other urban waste. The taxonomic profiling of metatranscriptome sequences suggests that members of Gammaproteobacteria and Deltaproteobacteria classes contribute to the detoxification of the polluted soil. Desulfobacterium autotrophicum was the most abundant microorganism in the oil-impacted site and displayed specific functions related to heavy metal resistance, potentially playing a key role in the successful persistence of the microbial community of this site.

This study classifies urban environments into types characterized by different exposure to environmental risk factors measured by general sense of discomfort and Heart Rate Variability (HRV). We hypothesize that a set of environmental factors (micro-climatic, CO, noise and individual heart rate) that were measured simultaneously in random locations can provide a better understanding of the distribution of human exposure to environmental loads throughout the urban space than results calculated based on measurements from close fixed stations. We measured micro-climatic and thermal load, CO and noise, individual Heart Rate, Subjective Social Load and Sense of Discomfort (SD) were tested by questionnaire survey.The results demonstrate significant differences in exposure to environmental factors among 8 types of urban environments. It appears that noise and social load are the more significant environmental factors to enhance health risks and general sense of discomfort.

The rapid growth of the production of electrical and electronic products has meant an equally rapid growth in the amount of electronic waste (e-waste), much of which is illegally imported to India, for disposal presenting a serious environmental challenge. The environmental impact during e-waste recycling was investigated and metal as well as other pollutants [e.g. polybrominated diphenyl ethers (PBDEs), polychlorinated biphenyls (PCBs)] were found in excessive levels in soil, water and other habitats. The most e-waste is dealt with as general or crudely often by open burning, acid baths, with recovery of only a few materials of value. As resulted of these process; dioxins, furans, and heavy metals are released and harmful to the surrounding environment, engaged workers, and also residents inhabiting near the sites. The informal e-waste sectors are growing rapidly in the developing countries over than in the developed countries because of cheapest labor cost and week legislations systems. It has been confirmed that contaminates are moving through the food chain via root plant translocation system, to the human body thereby threatening human health. We have suggested some possible solution toward in which plants and microbes combine to remediate highly contaminated sites.

High levels of polychlorinated dibenzo-p-dioxins (PCDDs) and polychlorinated dibenzofurans (PCDFs) were detected in free-range eggs, and these levels reached a concentration of 29.84 ± 7.45 pg of WHO-TEQ/g of fat. This value exceeded the EU maximum permitted level of 2.5 pg of WHO-TEQ/g of fat for PCDD/F congeners by twelve-fold. A chemical analysis (HRGC-HRMS) revealed elevated amounts of OCDD, OCDF, HxCDD, HpCDD and HpCDF. During the investigation, samples of feed, soil, wall scrapings, wooden ceiling of the henhouse and tissues from laying hens were examined for dioxin contents (30 samples altogether). The long and complicated investigation found that the source of dioxins in the poultry farm was pentachlorophenol-treated wood, which was used as structural components in the 40-year-old farm building adapted to a henhouse. The wooden building material contained PCDD/Fs at a concentration of 3922.60 ± 560.93 pg of WHO-TEQ/g and 11.0 ± 2.8 μg/kg of PCP. The potential risk associated with dioxin intake was characterized by comparing the theoretically calculated weekly and monthly intakes with the toxicological reference values (TRVs), namely the Tolerable Weekly Intake (TWI) and Provisional Tolerable Monthly Intake (PTMI) values of 14 pg of WHO-TEQ/kg of bw and 70 pg of WHO-TEQ/kg of bw, respectively. The intake of dioxins estimated for high egg consumers (approximately 5–6 eggs/week) exceeded the TWI and PTMI values, which may pose a risk of delayed adverse health effects. The estimated dose of PCDD/Fs and DL-PCBs for children consuming 5 eggs per week exceeded the TWI by as much as 450% because of their nearly 5-fold-lower body weight. Although the dioxin intake estimated for the average consumption of eggs in the general population did not exceed any of the TRVs applied (58.7% TWI and 51.1% PTMI), such a situation should be considered unacceptable from a public health perspective because eggs are not the only source of these contaminants.

Arsenic is a non-threshold carcinogenic metalloid. Thus, human exposure should be minimised, e.g. by chemically stabilizing As in soil. Since iron is a potential As immobiliser, it was investigated whether root iron plaque, formed under aerobic conditions, affects As uptake, metabolism and distribution in Lupinus albus plants. White lupin plants were cultivated in a continuously aerated hydroponic culture containing Fe/EDDHA or FeSO4 and exposed to arsenate (5 or 20 μM). Only FeSO4 induced surficial iron plaque in roots. LA-ICP-MS analysis accomplished on root sections corroborated the association of As to this surficial Fe. Additionally, As(V) was the predominant species in FeSO4-treated roots, suggesting less efficient As uptake in the presence of iron plaque. Fe/EDDHA-exposed roots neither showed such surficial FeAs co-localisation nor As(V) accumulation; in contrast As(III) was the predominant species in root tissue. Furthermore, FeSO4-treated plants showed reduced shoot-to-root As ratios, which were >10-fold lower compared to Fe/EDDHA treatment. Our results highlight the role of an iron plaque formed in roots of white lupin under aerobic conditions on As immobilisation. These findings, to our knowledge, have not been addressed before for this plant and have potential implications on soil remediation (phytostabilisation) and food security (minimising As in crops).

Increasing trace metal pollution in river sediment poses a significant threat to watershed ecosystem health. Identifying potential sources of sediment metals and apportioning their contributions are of key importance for proposing prevention and control strategies of river pollution. In this study, three advanced multivariate receptor models, factor analysis with nonnegative constraints (FA-NNC), positive matrix factorization (PMF), and multivariate curve resolution weighted-alternating least-squares (MCR-WALS), were comparatively employed for source apportionment of trace metals in river sediments and applied to the Le'an River, a main tributary of Poyang Lake which is the largest freshwater lake in China. The pollution assessment with contamination factor and geoaccumulation index suggested that the river sediments in Le'an River were contaminated severely by trace metals due to human activities. With the three apportionment tools, similar source profiles of trace metals in sediments were extracted. Especially, the MCR-WALS and PMF models produced essentially the same results. Comparatively speaking, the weighted schemes might give better solutions than the unweighted FA-NNC because the uncertainty information of environmental data was considered by PMF and MCR-WALS. Anthropogenic sources were apportioned as the most important pollution sources influencing the sediment metals in Le'an River with contributions of about 90%. Among them, copper tailings occupied the largest contribution (38.4–42.2%), followed by mining wastewater (29.0–33.5%), and agricultural activities (18.2–18.7%). To protect the ecosystem of Le'an River and Poyang Lake, special attention should be paid to the discharges of mining wastewater and the leachates of copper tailing ponds in that region.

In this work, source pollution tracing of the sediments of the Danube River and its tributaries in Serbia was performed using sterol ratios. Improved liquid chromatography-tandem mass spectrometry method, which enabled complete chromatographic separation of four analytes with identical fragmentation reactions (epicoprostanol, coprostanol, epicholestanol and cholestanol), was applied for the determination of steroid compounds (hormones, human/animal and plant sterols). A widespread occurrence of sterols was identified in all analyzed samples, whereas the only detected hormones were mestranol and 17α-estradiol. A human-sourced sewage marker coprostanol was detected at the highest concentration (up to 1939 ng g−1). The ratios between the key sterol biomarkers, as well as the percentage of coprostanol relative to the total sterol amount, were applied with the aim of selecting the most reliable for distinction between human-sourced pollution and the sterols originated from the natural sources in river sediments. The coprostanol/(cholesterol + cholestanol) and coprostanol/epicoprostanol ratios do not distinguish between human and natural sources of sterols in the river sediments in Serbia. The most reliable sterol ratios for the sewage pollution assessment of river sediments in the studied area were found to be coprostanol/(coprostanol + cholestanol), coprostanol/cholesterol and epicoprostanol/coprostanol. For the majority of sediments, human-derived pollution was determined. Two sediment samples were identified as influenced by a combination of human and natural biogenic sources.

Methylmercury (MeHg), a neurotoxin, is a global concern because of its potential risk to human and ecological health. Elevated mercury (Hg) concentrations were recently reported in the Tibetan Plateau (TP) due to increasing Hg input from distant regions, yet little is known about MeHg production and distribution in the terrestrial ecosystems of the TP. Here, we report longitudinal occurrence of MeHg and the factors regulating net MeHg production in 23 grassland sites from eastern to western TP. The soil MeHg content varied from 0.002 to 0.058 ng g−1, with different distribution patterns between the eastern and western TP. There was a positive correlation between the MeHg concentration and the longitude after 90 °E, which is similar to the distribution patterns of the total mercury (THg), water and organic carbon in this region. Average MeHg concentration in topsoil is generally higher than that in subsoil. Our results show that MeHg concentration in soils of the TP is directly affected by soil water, potential microbial methylators and THg, while indirectly regulated by soil organic carbon through the microbial community and the longitude-dependent precipitation through soil water. Our study suggests that soil water is the most important driver regulating net MeHg production in the grasslands of the TP. These findings have important implications for unraveling the mechanism of net production of MeHg in high-altitude environments.

As one of the most notorious atmospheric pollutants, NOx not only promotes the formation of ozone but also has adverse health effects on humans. It is therefore of great importance to study the sources of NOx and its effects on human health. The Comprehensive Air Quality Model (CAMx) modeling system and ozone source apportionment technology (OSAT) were used to study the contribution of NOx from different emission sources over southern China. The results indicate that heavy duty diesel vehicles (HDDVs) and industrial point sources are the two major local NOx sources, accounting for 30.8% and 18.5% of local NOx sources, respectively. In Hong Kong, marine emissions contributed around 43.4% of local NOx in 2011. Regional transport is another important source of this pollutant, especially in February and November, and it can contribute over 30% of ambient NOx on average. Power plant point emission is an significant regional source in Zhuhai, Zhongshan and Foshan. The total emission sources are estimated to cause 2119 (0–4405) respiratory deaths and 991 (0–2281) lung cancer deaths due to long-term exposure to NOx in the Pearl River Delta region. Our results suggest that local governments should combine their efforts and vigorously promote further reduction of NOx emissions, especially for those sources that make a substantial contribution to NOx emissions and affect human health: HDDV, LDGV, industrial point sources and marine sources.