Human exposure to organic contaminants is widespread. Many of these contaminants show adverse health effects on human population. Human biomonitoring (HBM) follows the levels and the distribution of biomarkers of exposure (BoE), but it is usually done in a targeted manner. Suspect and non-targeted screening (SS/NTS) tend to find BoE in an agnostic way, without preselection of compounds, and include finding evidence of exposure to predicted, unpredicted known and unknown chemicals. This study describes the application of high-resolution mass spectrometry (HRMS)-based SS/NTS workflow for revealing organic contaminants in urine of a cohort of 200 children from Slovenia, aged 6–9 years. The children originated from two regions, urban and rural, and the latter were sampled in two time periods, summer and winter. We tentatively identified 74 BoE at the confidence levels of 2 and 3. These BoE belong to several classes of pharmaceuticals, personal care products, plasticizers and plastic related products, volatile organic compounds, nicotine, caffeine and pesticides. The risk of three pesticides, atrazine, amitraz and diazinon is of particular concern since their use was limited in the EU. Among BoE we tentatively identified compounds that have not yet been monitored in HBM schemes and demonstrate limited exposure data, such as bisphenol G, polyethylene glycols and their ethers. Furthermore, 7 compounds with unknown use and sources of exposure were tentatively identified, either indicating the entry of new chemicals into the market, or their metabolites and transformation products. Interestingly, several BoE showed location and time dependency. Globally, this study presents high-throughput approach to SS/NTS for HBM. The results shed a light on the exposure of Slovenian children and raise questions on potential adverse health effects of such mixtures on this vulnerable population.

Wastewater reclamation and reuse for agriculture have attracted a great deal of interest, due to water stress caused by rapid increase in human population and agricultural water demand as well as climate change. However, the application of treated wastewater for irrigation can lead to the accumulation of pharmaceuticals and personal care products (PPCPs) in the agricultural crops, grazing animals, and consequently to human dietary exposure. In this study, a model was developed to simulate the fate of five PPCPs; triclosan (TCS), carbamazepine (CBZ), naproxen (NPX), gemfibrozil (GFB), and fluoxetine (FXT) during wastewater reuse for agriculture, and potential human dietary exposure and health risk. In a reclaimed wastewater-irrigated grazing farm growing alfalfa, it took 100–535 days for PPCPs to achieve the steady-state concentrations of 1.43 × 10⁻⁶, 4.73 × 10⁻⁵, 1.17 × 10⁻⁶, 1.53 × 10⁻⁵, and 7.38 × 10⁻⁶ mg/kg for TCS, CBZ, NPX, GFB, and FXT in soils, respectively. The accumulated concentration of PPCPs in the plant (alfalfa) and grazing animals (beef) ranged 2.86 × 10⁻⁷− 4.02 × 10⁻³ and 4.39 × 10⁻¹⁵− 6.27 × 10⁻⁷ mg/kg, respectively. Human dietary exposure to these compounds through beef consumption was calculated to be 1.67 × 10⁻¹⁸− 1.74 × 10⁻¹⁰ mg/kg bodyweight/d, much lower than the acceptable daily intake (ADI). Similar results were obtained for a ‘typical’ reclaimed wastewater irrigated farm based on the typical setup using our model. Screening analysis showed that PPCPs with relatively high LogD value and lower ratios of degradation rate (in soils) to plant uptake have a greater potential to be transferred to humans and cause potential health risks. We established a modeling method for evaluating the fate and human health effects of PPCPs in reclaimed wastewater reuse for the agricultural system and developed an index for screening PPCPs with high potential to accumulate in agricultural products. The model and findings are valuable for managing water reuse for irrigation and mitigating the harmful effects of PPCPs.

Different scientific reports suggested link between exposure to radiofrequency radiation (RF) from mobile communications and induction of reactive oxygen species (ROS) and DNA damage while other studies have not found such a link. However, the available studies are not directly comparable because they were performed at different parameters of exposure, including carrier frequency of RF signal, which was shown to be a critical for appearance of the RF effects. For the first time, we comparatively analyzed genotoxic effects of UMTS signals at different frequency channels used by 3G mobile phones (1923, 1947.47, and 1977 MHz). Genotoxicity was examined in human lymphocytes exposed to RF for 1 h and 3 h using complimentary endpoints such as induction of ROS by imaging flow cytometry, DNA damage by alkaline comet assay, mutations in TP53 gene by RSM assay, preleukemic fusion genes (PFG) by RT-qPCR, and apoptosis by flow cytometry. No effects of RF exposure on ROS, apoptosis, PFG, and mutations in TP53 gene were revealed regardless the UMTS frequency while inhibition of a bulk RNA expression was found. On the other hand, we found relatively small but statistically significant induction of DNA damage in dependence on UMTS frequency channel with maximal effect at 1977.0 MHz. Our data support a notion that each specific signal used in mobile communication should be tested in specially designed experiments to rule out that prolonged exposure to RF from mobile communication would induce genotoxic effects and affect the health of human population.

Using multivariate statistical analysis, the study evaluated anthropogenic sources of river water contamination and their relationships with river water quality in the Haicheng River basin near to the Liaodong Bay in Northeast China. The results showed that nitrogen (N) and phosphorous (P) were identified as the main pollutants in the river water by factor analysis. Human population and elevational gradient were all significantly correlated with N, P, and other water quality variables in correlation analysis and explained chemical oxygen demand (COD), N, and P variables from 23.9% (TN) to 53.1% (NH3+-N) of the total variances in regression analysis, indicating that population and its distribution were all responsible for river contaminations, especially for COD, N, and P contaminations. The excessive applications of fertilizers and pesticides were all positively correlated with nitrogen variables and nitrogen pollution factor in correlation analysis, suggesting that agricultural activities were contributed to the river nitrogen pollution. Due to inadequate or lack wastewater treatment facilities, huge amounts of domestic sewage and industrial effluents were released into the river, becoming the predominant anthropogenic sources for the river water deterioration of COD, N, and P. Multivariate statistical analysis provided useful tools to correlate sources of contamination with water quality data. This approach will provide a better management for river pollution control in a human-driven river ecosystem.

Coastal zone is of great importance in the provision of various valuable ecosystem services. However, it is also sensitive and vulnerable to environmental changes due to high human populations and interactions between the land and ocean. Major threats of pollution from over enrichment of nutrients, increasing metals and persistent organic pollutants (POPs), and climate change have led to severe ecological degradation in the coastal zone, while few studies have focused on the combined impacts of pollution and climate change on the coastal ecosystems at the global level. A global overview of nutrients, metals, POPs, and major environmental changes due to climate change and their impacts on coastal ecosystems was carried out in this study. Coasts of the Eastern Atlantic and Western Pacific were hotspots of concentrations of several pollutants, and mostly affected by warming climate. These hotspots shared the same features of large populations, heavy industry and (semi-) closed sea. Estimation of coastal ocean capital, integrated management of land-ocean interaction in the coastal zone, enhancement of integrated global observation system, and coastal ecosystem-based management can play effective roles in promoting sustainable management of coastal marine ecosystems. Enhanced management from the perspective of mitigating pollution and climate change was proposed.

Polycyclic aromatic hydrocarbons (PAHs) are a category of over 100 various chemicals released from numerous combustion sources. The ubiquity and toxicity of PAHs have posed high health risks on human populations. This study aims to examine the long-term trends of atmospheric PAHs at the national-level in the U.S., and evaluate their cancer risks. Daily concentrations of PAHs measured at 169 monitoring stations between 1990 and 2014 were obtained from the U.S. Environmental Protection Agency's Air Quality System. Temporal trends were examined using generalized linear model with generalized estimating equations. Random-effects analysis of variance was performed to explore variance between regions, sites, years, and months with a hierarchical structure. Source categories were identified using diagnostic ratios. National population level cancer risks were estimated using the relative potency factors and inhalation unit risk method. Ambient PAH concentrations displayed an overall downward trend (6–9% annual reduction) in urban areas, but not in rural areas. Seasonal and weekday/weekend effects were significant. Urban concentrations were twice of the rural level. The between-site variation outweighed the temporal variation, indicating large spatial heterogeneity. The predominant PAH sources were from traffic and non-traffic related fuel combustions with a dominant contribution from diesel emissions. The average excess lifetime cancer risk was estimated to be 9.3 ± 30.1 × 10−6 (GM: 4.2 × 10−6) from exposure to ten carcinogenic PAHs. This is the first comprehensive study of the spatiotemporal trends of ambient PAHs at the U.S. national level. The results indicate that future efforts aimed to reduce PAH exposures should focus on diesel emission controls and extending the geographic coverage of air monitoring.

Trees remove air pollutants through dry deposition processes depending upon forest structure, meteorology, and air quality that vary across space and time. Employing nationally available forest, weather, air pollution and human population data for 2010, computer simulations were performed for deciduous and evergreen trees with varying leaf area index for rural and urban areas in every county in the conterminous United States. The results populated a national database of annual air pollutant removal, concentration changes, and reductions in adverse health incidences and costs for NO2, O3, PM2.5 and SO2. The developed database enabled a first order approximation of air quality and associated human health benefits provided by trees with any forest configurations anywhere in the conterminous United States over time.Comprehensive national database of tree effects on air quality and human health in the United States was developed.

Since early 1980s, chemical pollution has become a serious environmental problem in rapidly developing China. This study reviewed the policy and legal framework for monitoring and management of chemical pollutants in China, with reference to the relevant experience in other jurisdictions. Although efforts in environmental monitoring of chemical contamination have been substantially increased over the last decade, China is lagging behind in terms of nationwide monitoring of chemical contamination in human population, and standardization of sampling and analytical protocols. While actively participating in various international treaties and conventions related to pollution control, China also has a very comprehensive set of environmental laws and policies. These include the newly enacted legislation on the control of new chemicals (i.e., China REACH) and the development of a set of National Environmental Standards. In addition to environmental education, these new measures will further enhance the control of chemical pollutants and facilitate effective law enforcement.

Chlorinated polyfluoroalkyl ether sulfonates (Cl-PFESAs), are ubiquitous alternatives to perfluorooctane sulfonate (PFOS), a widely used poly- and perfluoroalkyl substance (PFAS). Despite in vivo and in vitro evidence of metabolic toxicity, no study has explored associations of Cl-PFESAs concentrations with metabolic syndrome (MetS) in a human population. To help address this data gap, we quantified 32 PFAS, including 2 PFOS alternative Cl-PFESAs (6:2 and 8:2 Cl-PFESAs) in serum from 1228 adults participating in the cross-sectional Isomers of C8 Health Project in China study. The odds ratios (ORs) and 95% confidence intervals (CIs) of MetS and its various components were estimated using individual PFAS as a continuous or categorical predictor in multivariate regression models. The association between the overall mixture of PFAS and MetS was examined using probit Bayesian Kernel Machine Regression (BKMR-P). Greater serum PFAS concentrations were associated with higher odds of MetS and demonstrated a statistically significant dose-response trend (P for trend < 0.001). For example, each ln-unit (ng/mL) increase in serum 6:2 Cl-PFESA was associated with a higher prevalence of MetS (OR = 1.52, 95% CI: 1.25, 1.85). MetS was also 2.26 (95% CI: 1.59, 3.23) times more common in the highest quartile of serum 6:2 Cl-PFESA concentration than the lowest, and particularly high among women (OR = 6.41, 95% CI: 3.65, 11.24). The BKMR-P analysis showed a positive association between the overall mixture of measured PFAS and the odds of MetS, but was only limited to women. While our results suggest that exposure to Cl-PFESAs was associated with MetS, additional longitudinal studies are needed to more definitively address the potential health concerns of these PFOS alternatives.

Toxic metals have been linked to a range of adverse health effects in freshwater organisms. However, for higher vertebrates, there is little understanding of the large-scale drivers of exposure. We quantified toxic metal/semi-metal concentrations in a sentinel freshwater top predator, the Eurasian otter (Lutra lutra), across England and Wales, and determined how this varied with key natural and anthropogenic factors. We related liver concentrations in 278 otters that died between 2006 and 2017 to habitat biogeochemistry, proximity to point source contamination and to biological characteristics (length, sex, condition). Evidence for any positive association with putative anthropogenic sources (mining, human population, known discharges) was weak or lacking in nearly all cases, with the exception of a positive association between lead and human population density. Despite concerns that burgeoning use of nanosilver in consumer products might increase silver concentrations in waste waters, there was no increase over time. Spatial variation in soil/sediment pH, precipitation, and soil calcium oxide are indicated as significant predictors of metal concentrations in otters (higher cadmium and silver in areas with lower pH and higher rainfall, and higher chromium and lead in areas of lower calcium oxide). Liver chromium and nickel concentrations declined significantly over time (Cr 0.030 ± 1.2 to 0.015 ± 1.3 μg/g dry weight, Ni 0.0038 ± 1.2 to 0.00068 ± 1.5 μg/g, between 2006–2009 and 2014–2017), but other metals showed no temporal change. Biotic associations were important, with age related accumulation indicated for mercury and cadmium (as well as interactions with body condition). Our results suggest that larger-scale geochemical and hydrological processes are important in determining metal exposure in otters, and we provide an indication of risk factors that may be of relevance for freshwater vertebrates in other countries with well-developed water pollution management.