A regional investigation in the Youxian prefecture, southern China, was conducted to analyze the impact of environmental factors including soil properties and irrigation in conjunction with the use of fertilizers on the accumulation of Cd in vegetables. The Cd transfer potential from soil to vegetable was provided by the plant uptake factor (PUF), which varied by three orders of magnitude and was described by a Gaussian distribution model. The soil pH, content of soil organic matter (SOM), concentrations of Zn in the soil, pH of irrigation water and nitrogenous fertilizers contributed significantly to the PUF variations. A path model analysis, however, revealed the principal control of the PUF values resulted from the soil pH, soil Zn concentrations and SOM. Transfer functions were developed using the total soil Cd concentrations, soil pH, and SOM. They explained 56% of the variance for all samples irrespective of the vegetable genotypes. The transfer functions predicted the probability of exceeding China food safety standard concentrations for Cd in four major consumable vegetables under different soil conditions. Poor production practices in the study area involved usage of soil with pH values ≤ 5.5, especially for the cultivation of Raphanus sativus L., even with soil Cd concentrations below the China soil quality standard. We found the soil standard Cd concentrations for cultivating vegetables was not strict enough for strongly acidic (pH ≤ 5.5) and SOM-poor (SOM ≤ 10 g kg−1) soils present in southern China. It is thus necessary to address the effect of environmental variables to generate a suitable Cd threshold for cultivated soils.

A total of 21 surface sediments collected from the Yellow River Estuary, China were analyzed for 40 kinds of polybrominated diphenyl ethers (PBDEs) using gas chromatography-mass spectrometry (GC–MS). Their levels, spatial distribution, congener profiles and possible sources were investigated. Only ten congeners were detected in the sediments. The total concentrations of the lower brominated BDEs (∑PBDEslow, PBDEs excluding BDE 209) and BDE 209 ranged from 0.482 ng/g to 1.07 ng/g and 1.16–5.40 ng/g, with an average value of 0.690 and 2.79 ng/g, respectively, which were both at the low end of the global contamination level. The congener profiles were dominated by BDE 209, with the average value accounting for 79.2% of the total PBDEs in the sediment samples. Among the nine lower brominated BDE congeners, BDE 47, 99 and 183 had high abundances. Although the commercial Penta/Octa-BDE products have been banned in most countries, the residual commercial Penta/Octa/Deca-BDE products and the debromination of highly brominated BDE compounds such as BDE 209 were still found to be the possible sources for the trace level of PBDEs in the present study area. In spite of the gradual removal of the commercial PBDEs in the world, the present research results further suggested that scientific attention should not be reduced on the issue of environmental contamination caused by these outdated chemical compounds.

The sensitivity of a source apportionment model to mobile source profiles was examined to determine the impact of using non-local mobile source profiles in chemical mass balance (CMB) models. We examined the impact of USA and Chinese mobile source profiles on source apportionment results in St. Louis, Missouri, and Beijing. The results showed that the use of non-local mobile source profiles did not impact the model apportionment results for vegetative detritus and biomass burning, but other primary source contributions were influenced by the use of non-local source profiles. Secondary organic carbon (SOC) contributions estimated by the CMB models with local and non-local profiles were compared to estimate of SOC from the EC tracer method and were found to be consistent with little bias. The results also showed that it is feasible to use the USA mobile profiles in China while model results were biased by using Chinese mobile profiles in the USA. Monthly and annual average concentrations of molecular markers in the source apportionment model showed lower sensitivity to source profiles than daily measurements, which has implications to the design of source apportionment studies.

Mercury (Hg) is recognized as a dangerous contaminant due to its bioaccumulation and biomagnification within trophic levels, leading to serious health risks to aquatic biota. Therefore, there is an urgent need to unravel the mechanisms underlying the toxicity of Hg. To this aim, a metabolomics approach based on protonic nuclear magnetic resonance (1H NMR), coupled with chemometrics, was performed on the gills of wild golden grey mullets L. aurata living in an Hg-polluted area in Ria de Aveiro (Portugal). Gills were selected as target organ due to their direct and continuous interaction with the surrounding environment. As a consequence of accumulated inorganic Hg and methylmercury, severe changes in the gill metabolome were observed, indicating a compromised health status of mullets. Numerous metabolites, i.e. amino acids, osmolytes, carbohydrates, and nucleotides, were identified as potential biomarkers of Hg toxicity in fish gills. Specifically, decrease of taurine and glycerophosphocholine, along with increased creatine level, suggested Hg interference with the ion-osmoregulatory processes. The rise of lactate indicated anaerobic metabolism enhancement. Moreover, the increased levels of amino acids suggested the occurrence of protein catabolism, further supported by the augmented alanine, involved in nitrogenous waste excretion. Increased level of isobutyrate, a marker of anoxia, was suggestive of onset of hypoxic stress at the Hg contaminated site. Moreover, the concomitant reduction in glycerophosphocholine and phosphocholine reflected the occurrence of membrane repair processes. Finally, perturbation in antioxidant defence system was revealed by the depletion in glutathione and its constituent amino acids. All these data were also compared to the differential Hg-induced metabolic responses previously observed in liver of the same mullets (Brandão et al., 2015). Overall, the environmental metabolomics approach demonstrated its effectiveness in the evaluation of Hg toxicity mechanisms in wild fish under realistic environmental conditions, uncovering tissue-specificities regarding Hg toxic effects namely in gills and liver.

To assess pollution levels of major inorganic nitrogen species and their atmospheric deposition input to sensitive ecosystems in Sichuan Basin, southwest China, ambient concentrations of oxidized (NOy ∼ NO2, HNO3, NO3−) and reduced (NHx = NH3, NH4+) nitrogen species were collected at two urban sites during four one-month periods, each in a different season from July 2014 to April 2015. Estimated annual mean concentration of NOy was 20.3 and 13.5 μg N m−3 in Chengdu and Wanzhou, respectively, and NHx was 16.9 and 13.6 μg N m−3, respectively. Back trajectory cluster analysis indicated that high levels of NOy and NHx in Chengdu were mainly caused by local emissions while those in Wanzhou were caused by both the local emissions and long-range transport of pollutants. On annual basis, NO2 contributed the most to NOy, followed by NO3− and HNO3, accounting for 87.5%, 10.5% and 2.0%, respectively, of NOy in Chengdu, and 91.4%, 6.9% and 1.7%, respectively, in Wanzhou. NH3 was the predominant contributor to NHx, contributing 65.6% and 72.2% in Chengdu and Wanzhou, respectively. Dry deposition fluxes were estimated using the inferential method with measured ambient concentrations and modelled dry deposition velocities. The total inorganic nitrogen dry deposition flux was estimated to be 21.4 and 8.5 kg N ha−1 yr−1, with 44.3% and 41.4% from NOy in Chengdu and Wanzhou, respectively. NO2 and NH3 each contributed about 80% of NOy and NHx dry deposition, respectively. Wet deposition was only collected in Wanzhou, where the annual wet deposition of NO3− and NH4+ was 4.5 and 15.7 kg N ha−1 yr−1, respectively. The total wet plus dry deposition was 28.7 kg N ha−1 yr−1 in Wanzhou with 72.2% from reduced nitrogen. Therefore, controlling NH3 emissions from agricultural, traffic, waste containers and sewage system sources would be effective to reduce the total nitrogen deposition in the Sichuan Basin area.

The level of phthalate esters (PAEs) alone is not considered to be a sufficient indicator of PAE pollution due to the quick metabolism of PAEs in the biota. The primary metabolites of PAEs, monoalkyl phthalate esters (MPEs), may also be an important indicator. However, PAE metabolism has scarcely been documented in wild marine organisms. We analysed five PAEs [dimethyl phthalate (DMP), diethyl phthalate (DEP), di-n-butyl phthalate (DBP), di(2-ethylhexyl) phthalate (DEHP), and di-n-octyl phthalate (DNOP)] and their corresponding MPEs [mono-methyl phthalate (MMP), mono-ethyl phthalate (MEP), mono-n-butyl phthalate (MBP), mono-2-ethylhexyl phthalate (MEHP), and mono-n-octyl phthalate (MNOP)] in 95 wild aquatic marine samples (including fish, prawns and molluscs) collected from the Yangtze River Delta area of the East China Sea. The species-dependent distribution of these compounds was associated with the food habits, living patterns and trophic levels of the biota. Slightly higher levels of hydrophobic PAEs (DBP and DEHP, logKOW 4.27 and 7.33, respectively) were observed in fish species consuming benthic organisms or in demersal fish species, suggesting the importance of benthic organisms and sediment. Trophic dilution of both PAEs and MPEs implies further metabolic transformation at higher trophic levels. MPE tissue distributions in fish demonstrate that the highest concentrations were always observed in bile. Metabolism via the kidney and gill is a probable main way for the relatively less hydrophobic MPEs (logKOW = <4.73, from MMP to MEHP), whereas metabolism via the liver is likely the main way for the most hydrophobic MNOP (logKOW 5.22). Generally, higher detection frequencies of MPEs were observed than those of parent PAEs. Significant liner correlations were observed between the levels of short-branched (carbon atom per chain = <4) MPEs and the sum of PAEs and MPEs (n = 95, p < 0.01), demonstrating that short-branched MPEs can be used as biomarkers of exposure to quantitatively reflect parent PAE contamination in wild marine organisms.

The current study extends our previous findings concerning the sensitivity of Lymantria dispar larvae to cadmium in light of ecotoxicological risk assessment. Here we report the results of the comet assay performed for the first time on this species. We examined the chronic effects of two cadmium concentrations (50 and 100 μg Cd/g dry food) on DNA integrity and haemocyte viability, as well as on fitness-related traits (larval mass and development duration parameters). All parameters were assessed individually and then used to calculate the integrated biomarker response (IBR) index. Egg-masses of L. dispar were collected from two locations in Serbia - the uncontaminated Homolje mountains and a metal-polluted area near Bor copper mines, smelter and refinery. Distinctive patterns in the response of these populations to cadmium exposure were noticed. In haemocytes of larvae from the pollution-free location both cadmium treatments increased the level of DNA damage, although in a similar range. Haemocyte viability and larval mass were reduced, while duration of the fourth instar and total development time were prolonged in a concentration-dependent manner. Cadmium tolerance was noticeable in the population from the metal-contaminated site at all organizational levels. Nevertheless, haemocyte viability in that population was reduced by the stronger treatment. Haemocyte viability was recognized as a promising biomarker due to the evident response of both populations to dietary cadmium. Genotoxicity, fitness-related traits and the IBR index could be used for biomonitoring of sensitive populations not previously exposed to metals.

The formaldehyde (FA) is a crosslinking agent that reacts with cellular macromolecules such as proteins, nucleic acids and molecules with low molecular weight such as amino acids, and it has been linked to inflammatory processes and oxidative stress. This study aimed to analyze the oxidative effects on pulmonary inflammatory response in Fischer rats exposed to different concentrations of FA. Twenty-eight Fischer rats were divided into 4 groups (N = 7). The control group (CG) was exposed to ambient air and three groups were exposed to different concentrations of FA: 1% (FA1%), 5% (FA5%) and 10% (FA10%). In the Bronchoalveolar Lavage Fluid (BALF), the exposure to a concentration of 10% promoted the increase of inflammatory cells compared to CG. There was also an increase of macrophages and lymphocytes in FA10% and lymphocytes in FA5% compared to CG. The activity of NADPH oxidase in the blood had been higher in FA5% and FA10% compared to CG. The activity of superoxide dismutase enzyme (SOD) had an increase in FA5% and the activity of the catalase enzyme (CAT) showed an increase in FA1% compared to CG. As for the glutathione system, there was an increase in total glutathione (tGSH), reduced glutathione (GSH) and oxidized glutathione (GSSG) in FA5% compared to CG. The reduced/oxidized glutathione ratio (GSH/GSSG) had a decrease in FA5% compared to CG. There was an increase in lipid peroxidation compared to all groups and the protein carbonyl formation in FA10% compared to CG. We also observed an increase in CCL2 and CCL5 chemokines in the treatment groups compared to CG and in serum there was an increase in CCL2, CCL3 and CCL5 compared to CG. Our results point out to the potential of formaldehyde in promoting airway injury by increasing the inflammatory process as well as by the redox imbalance.

The effluents from wastewater treatment plants have been recognized as a significant environmental reservoir of antibiotics and antibiotic resistance genes (ARGs). Reclaimed water irrigation (RWI) is increasingly used as a practical solution for combating water scarcity in arid and semiarid regions, however, impacts of RWI on the patterns of ARGs and the soil bacterial community remain unclear. Here, we used high-throughput quantitative PCR and terminal restriction fragment length polymorphism techniques to compare the diversity, abundance and composition of a broad-spectrum of ARGs and total bacteria in 12 urban parks with and without RWI in Victoria, Australia. A total of 40 unique ARGs were detected across all park soils, with genes conferring resistance to β-lactam being the most prevalent ARG type. The total numbers and the fold changes of the detected ARGs were significantly increased by RWI, and marked shifts in ARG patterns were also observed in urban parks with RWI compared to those without RWI. The changes in ARG patterns were paralleled by a significant effect of RWI on the bacterial community structure and a co-occurrence pattern of the detected ARG types. There were significant and positive correlations between the fold changes of the integrase intI1 gene and two β-lactam resistance genes (KPC and IMP-2 groups), but no significant impacts of RWI on the abundances of intI1 and the transposase tnpA gene were found, indicating that RWI did not improve the potential for horizontal gene transfer of soil ARGs. Taken together, our findings suggested that irrigation of urban parks with reclaimed water could influence the abundance, diversity, and compositions of a wide variety of soil ARGs of clinical relevance.Irrigation of urban parks with treated wastewater significantly increased the abundance and diversity of various antibiotic resistance genes, but did not significantly enhance their potential for horizontal gene transfer.

Recently it became known that Volkswagen Group has been cheating with emission tests for diesel engines over the last six years, resulting in on-road emissions vastly exceeding legal standards for nitrogen oxides in Europe and the United States. Here, we provide an estimate of the public health consequences caused by this fraud. From 2009 to 2015, approximately nine million fraudulent Volkswagen cars, as sold in Europe and the US, emitted a cumulative amount of 526 ktonnes of nitrogen oxides more than was legally allowed. These fraudulent emissions are associated with 45 thousand disability-adjusted life years (DALYs) and a value of life lost of at least 39 billion US dollars, which is approximately 5.3 times larger than the 7.3 billion US dollars that Volkswagen Group has set aside to cover worldwide costs related to the diesel emissions scandal.