Two areas in central-southern Italy Land of Fires in Campania and Valley of Sacco river in Lazio are known to be contaminated sites, the first due to illegal fly-tipping and toxic fires, and the second due to an intensive industrial exploitation done by no-scruple companies and crooked public administration offices with dramatic consequences for environment and resident people. The work is intended to contribute to Human BioMonitoring (HBM) studies conducted in these areas on healthy young male population by a semiconductor gas sensor array trained by SPME-GC/MS. Human semen, blood and urine were investigated. The fingerprinting of the Volatile Organic Compounds (VOCs) by a gas sensors system allowed to discriminate the different contamination of the two areas and was able to predict the chemical concentration of several VOCs identified by GC/MS.

Rare earth elements (REE) have become essential in high- and green-technologies. Their increasing use lead to the release of anthropogenic REE into the environment including aquatic systems. The limited data available on the aquatic ecotoxicology of REE indicate their biological effects are highly dependent on their speciation, posing challenges for a reliable environmental risk assessment (ERA). The current study assessed the influence of speciation on the toxicity of neodymium (Nd), gadolinium (Gd) and ytterbium (Yb) in the Daphnia magna mobility inhibition test (ISO 6341:2012). REE toxicity was assessed individually and in ternary mixture, in the absence and presence of dissolved organic matter (DOM). Speciation was predicted by modeling and REE bioaccumulation by D. magna was measured to better understand the relationship between REE speciation and toxicity. DOM decreased significantly the toxicity of Nd, Gd and the mixture towards this freshwater crustacean. This was explained by a lower REE bioaccumulation in the presence of DOM due to REE-DOM complexation, which reduced REE bioavailability. DOM effects on Yb toxicity and bioaccumulation were limited because of Yb precipitation. We show that the way of expressing EC50 values (based on nominal, measured or predicted REE concentrations in solution) drastically changed REE toxicity assessment and that these changes were influenced by REE speciation. This study demonstrates for the first time that REE speciation, and especially REE-DOM complexation, significantly influences REE bioaccumulation and toxicity towards D. magna. Our results have implications for the subsequent ERA of REE.

The adsorption of hydrophobic organic compounds (HOCs) by microplastics (MPs) has attracted great attention in recent years. However, the ultimate environmental fate of the HOCs sorbed on MPs (HOCs-MPs) is poorly understood. In this work, we investigated the potential influence of the biotransformation process on the environmental fate of phenanthrene (PHE, a model HOC) sorbed on MPs (PHE-MPs) under the existence of humic acid (HA, the main ingredient of dissolved organic matter (DOM)) in the aquatic environment. The results indicated that the adsorption behavior of PHE on MPs decreased its bioavailability and thus inhibited its biotransformation efficiency. However, HA significantly promoted the biodegradation rate and percentage of PHE-MPs. This was probably because HA improved the desorption of PHE from MPs, which promoted the acquisition of PHE by bacteria from the aqueous phase. Further, HA dramatically increased the bacterial community diversity and richness and altered the community composition. The richness of some PHE-degrading bacteria, such as Methylobacillus and Sphingomonas, significantly increased, which may also be an important factor for promoting PHE biodegradation. Molecular ecological network analysis implied that HA enhanced the modularity and complexity of bacterial interaction networks, which was beneficial to maintaining the functional stability of the consortium QY1. Besides, HA decreased the cytotoxicity of functional microbes induced by HOCs-MPs. This work broadens our knowledge of the environmental fate of HOCs-MPs and interactions of MPs, HOCs, DOMs and functional microbial consortiums in aqueous environments.

The low value of nitrogen use efficiency (NUE) (around 30%) of crop production in China highlights the necessity to adopt reasonable N managements in national scale. After the implementation of ‘National Soil Testing and Formulated Fertilization’ program in 2005, many field experiments have reported an increase of NUE for crop productions in China. This has prompted discussion regarding the extent to which NUE in crop production has been improved. Here, we analyzed the temporal and spatial changes in NUE (crop N uptake/total N input) and cumulative synthetic and non-synthetic N fertilizer recovery efficiency of crop production in China during 1980–2014, and evaluated the relationship between NUE and economic growth (purchasing power parity, PPP) at national and provincial scale. The results showed that the overall NUE of crop production in China clearly increased from 35 to 42% during 2003–2014, and an increase in NUE was further evidenced by increases in cumulative recovery efficiency of both synthetic and non-synthetic N fertilizer. The relationship between NUE and PPP can be described by an environmental Kuznets curve at the national scale, with NUE first decreasing then increasing with PPP. However, this relationship exhibited large spatial variation: 1) In economically developed (e.g., Guangdong and Zhejiang) and undeveloped provinces (e.g., Yunnan and Guizhou), NUE generally decreased and then remained at low levels (20–35%) as PPP increased. 2) In major agricultural provinces with high (e.g., Shandong and Jiangsu) or intermediate levels (e.g., Hunan and Hebei) of economic development, a pronounced increasing trend in NUE with PPP was observed. These results highlight the necessity of developing region-oriented N management strategies to further increase the NUE of crop production in China, particularly in the economically developed and undeveloped provinces.

Many researches mention the need to identify the land-based sources of riverine macrolitter but few field data on litter amount, composition and sources are available in the scientific literature. Describing macrolitter hotspot dynamics would actually allow a better estimation of fluxes in the receiving environments and a better identification of the more appropriate mitigation strategies. This study provides new insights in roadway macrolitter production rates, typologies and input sources (i.e. deliberate or accidental). The macrolitter from an 800 m portion of a highly frequented roadway (around 90,000 vehicles per day) was collected during almost one year. Typologies were defined using the OSPAR/TGML classification. Results show high annual loads of macrolitter (42.8 kg/yr/ha), suggesting significant contributions of the road runoff to the litter fluxes in urban stormwater. Over the course of a year, 88.5 kg of debris were collected, including 53.2 kg (60%) of plastic debris. In total, 36,439 items were characterized, of which 84% were plastics. The macrodebris collected present a low diversity of components with Top 10 items accounting for 92% by count and a majority of small and lightweight items like plastic fragments (31%) or cigarette butts (18%). Input sources were estimated for 43% of the mass collected in which 37.2% were deliberately littered and 62.8% were accidental leaks, illustrating a major contribution of uncovered trucks and unsecured loads. The accumulation rates show a linear correlation with the road traffic. Such data are of prime interest since they enable to determine the potential contribution of road traffic to plastic fluxes to the environment.

The association between polycyclic aromatic hydrocarbons (PAHs) exposure and hearing loss is rarely assessed. We aimed to evaluate the relationship of polycyclic aromatic hydrocarbons (PAHs) exposure and hearing loss among US adults and adolescents, and to explore the mediating role of systemic inflammation in the associations. Participants from the National health and Nutrition Examination Surveys (NHANES, 2001–2016) were included. Multiple logistic regression models were used to explore the associations between PAH metabolites and hearing loss. A total of 4200 adults and 1337 adolescents were included in the present analysis. For adults, we found positive association between urinary PAH metabolites and hearing loss, including total, speech-frequency and high-frequency hearing loss. The odds ratios (ORs) and 95% confidence intervals (CIs) for each one-unit increase in the log-transformed level of 3-Hydroxyfluorene (3-OHFlu), 2-Hydroxyfluorene (2-OHFlu) and 2 & 3-Hydroxyphenanthrene (2&3-OHPh) with total hearing loss were 1.17 (1.04–1.31), 1.24 (1.07–1.43), and 1.18 (1.03–1.37), respectively. For adolescents, urinary PAH metabolites were positively associated with total and speech-frequency hearing loss, not with high-frequency. The ORs and 95% CIs for each one-unit increase in the log-transformed level of 3-OHFlu, 2-OHFlu and total urinary PAH metabolites with total hearing loss were 1.34 (1.06–1.68), 1.48 (1.13–1.93), and 1.33 (1.04–1.72), respectively. Each one-unit increase in the log-transformed level 2-OHFlu (β = 0.112, 95%CI = 0.018–0.206) and 2&3-OHPh (β = 0.145, 95%CI = 0.037–0.253) were positively associated with C-reactive protein (CRP) among adolescents, but not among adults. No mediating effect for CRP on the association of urinary PAH metabolites with hearing loss was found (all P > 0.05). 3-OHFlu and 2-OHFlu are associated with increased prevalence of hearing loss among adults and adolescents. Systemic inflammation does not mediate the associations. Further studies should be conducted to verify the results.

Once in the aquatic ecosystems, nanoplastics (NPls) can interact with other contaminants acting as vectors of transport and altering their toxicological effects towards organisms. Thus, the present study aims to investigate how polystyrene NPls (44 nm) interact with the herbicide phenmedipham (PHE) and affect its toxicity to zebrafish embryos. Single exposures to 0, 0.015, 0.15, 1.5, 15 and 150 mg/L NPls and 0.02, 0.2, 2 and 20 mg/L PHE were performed. Embryos were also exposed to the binominal combinations: 0.015 mg/L NPls + 2 mg/L PHE, 0.015 mg/L NPls + 20 mg/L PHE, 1.5 mg/L NPls + 2 mg/L PHE and 1.5 mg/L NPls + 20 mg/L PHE. Due to the low solubility of PHE in water, a solvent control was performed (0.01% acetone). PHE was quantified. Mortality, heartbeat and hatching rate, malformations appearance, locomotor behavior and biomarkers related to oxidative stress, neurotransmission and energy budgets were analyzed. During 96 h, NPls and PHE single and combined exposures did not affect embryos development. After 120 h, NPls induced hyperactivity and PHE induced hypoactivity. After 96 h, NPls increased catalase activity and PHE increased glutathione S-transferases activity. On the combination 0.015 mg/L NPls + 20 mg/L PHE, hyperactivity behavior was found, similar to 0.015 mg/L NPls, and cholinesterase activity was inhibited. Additionally, the combination 1.5 mg/L NPls + 20 mg/L PHE increased both catalase and glutathione S-transferases activities. The combination NPls with PHE affected more biochemical endpoints than the single exposures, showing the higher effect of the binominal combinations. Dissimilar interactions effects – no interaction, synergism and antagonism – between NPls and PHE were found. The current study shows that the effects of NPls on bioavailability and toxicity of other contaminants (e.g. PHE) cannot be ignored during the assessment of NPls environmental behavior and risks.

The high antibiotic resistance gene (ARGs) contents in livestock manure pose a potential risk to environment and human health. The heap composting with an ambient temperature and thermophilic composting are two methods for converting livestock manure into fertilizer. This study investigated the variations in ARGs and mobile genetic elements (MGEs) and revealed potential mechanisms for ARGs removal using the two composting methods. The ARGs abundance were enriched by 44-fold in heap composting, among them, the macrolide-resistance genes increased significantly. On the contrary, the ARGs were removed by 92% in thermophilic composting, among them, tetracycline-resistance genes decreased by 97%. The bacterial hosts of ARGs were associated with the variations of ARGs and MGEs. The tetO was correlated with the most diverse bacteria in heap composting, and Bacteroidetes was the major host bacteria. While tetT was correlated with the most diverse bacteria in thermophilic composting, and Proteobacteria was the major host bacteria. Structural equation models showed that the enrichment of ARGs in heap composting was mainly correlated with bacterial communities, whereas, the removal of ARGs in thermophilic composting was directly affect by MGEs. Composting temperature directly affected the variations in ARGs. Higher and lower temperatures significantly decreased and increased, respectively, ARGs and MGEs abundance levels.

The seasonal variation, spatial distribution, and ecological risks of thirteen organophosphate pesticides (OPPs) were studied in the Sundays and Swartkops estuaries in South Africa. Ten pesticides were detected in surface water samples from both estuaries, while all OPPs were detected in sediments. The highest concentration of OPPs (18.8 μg pyrazophos L⁻¹) was detected in surface water samples from Swartkops Estuary, while 48.7 μg phosalone kg⁻¹ dw was the highest in sediments collected from Sundays Estuary. There was no clear seasonal pattern in OPPs occurrence in surface water from both systems. However, their occurrence in sediments was in the following order: winter > autumn > summer > spring, perhaps indicating major pesticide input in the winter seasons. Results from ecological risk assessment showed that pyraclofos and chlorpyrifos (CHL) in surface water from both systems are respectively likely to cause high acute and chronic toxicity to fish (risk quotient – RQ > 1). For sediments of both estuaries, the highest acute and chronic RQs for fish were calculated for isazophos and CHL respectively. The majority of the detected OPPs in sediments posed potential high risks to Daphnia magna from both systems. These results suggest that these aquatic organisms (fish, and Daphnia), if present in the studied estuaries, can develop certain forms of abnormalities due to OPP exposure. To this end, proper measures should be taken to reduce OPP input into the estuarine systems.

This study examined the effect of tetracycline addition on arsenic (As) mobilization and biotransformation in two contrasting soils (upland soil and paddy soil) under flooded conditions. The soils with added tetracycline (0–50 mg kg⁻¹) were incubated for 30 days, and soil properties and microbial functional genes over time were quantified. Tetracycline significantly promoted As reduction and As release into porewater in both soils. The enhancement had resulted from an increase in the concentration of dissolved organic carbon and a decrease in soil redox potential. Tetracycline also increased the abundances of As-reducing genes (arsC and arrA) and the relative abundances of As-reducing bacteria Streptomyces, Bacillus, Burkholderia, Clostridium and Rhodococcus, all of which have been found resistant to tetracycline. These genera play a key part in stimulating As reduction in the presence of tetracycline. The study indicated the significance of tetracycline in the biochemical behavior of As in flooded soils and provided new insights into the potential effects of tetracycline on the quality and safety of agricultural products in the future.