China's economy has grown significantly and concomitantly so has the demand for home and personal care (HPC) products. The detection of chemicals used in HPC products is increasing in profile as China strives to improve its environmental management. China is developing robust exposure models for use in regulatory risk-based assessments of chemicals, including those chemicals used in HPC products. Accurate estimates of chemical emissions play an important role within this. A methodology is presented to derive spatially refined emissions from demographic and economic indicators with large variations in emissions calculated, showing product usage being higher in East and South China. The less affordable a product, the greater the influence per capita Gross Domestic Product has on the product distribution. Lastly, more spatially resolved input data highlights greater variation of product use. Linking product sales data with population density increased the observed variability in absolute usage distribution of HPC products at the county > province > regional > country scale.

Hexabromocyclododecanes (HBCDs) have been considered candidate persistent organic pollutants, however, environmental data on their presence in China, a major world market, are limited. In this study, airborne particle-bound HBCDs in Shanghai, China were quantified with liquid chromatography–tandem mass spectrometry, and their total concentrations varied from 3.21 to 123 pg/m³. The industrial area showed about three times higher HBCD levels than the urban areas. Gamma-HBCD dominated in particle-associated HBCDs in the industrial area, while α-HBCD was the major diastereomer of the urban areas, which is quite different from the pattern of technical products. Besides α-, β- and γ-HBCDs, δ-HBCD was also detected in all samples (0.09–6.31 pg/m³), while no ɛ-HBCD was found. Airborne β- and γ-HBCDs were racemic in most studied areas due to their chiral signatures showing no significant difference from commercial mixture. Fractions of (+)-α-HBCD (0.417–0.467), however, suggested the enrichment of (−)-α-HBCD and the involvement of enantioselective bioprocesses.

Mercury loads in tropical estuaries are largely controlled by the rainfall regime that may cause biodilution due to increased amounts of organic matter (both live and non-living) in the system. Top predators, as Trichiurus lepturus, reflect the changing mercury bioavailability situations in their muscle tissues. In this work two variables [fish weight (g) and monthly total rainfall (mm)] are presented as being important predictors of total mercury concentration (T-Hg) in fish muscle. These important explanatory variables were identified by a Weibull Regression model, which best fit the dataset. A predictive model using readily available variables as rainfall is important, and can be applied for human and ecological health assessments and decisions. The main contribution will be to further protect vulnerable groups as pregnant women and children. Nature conservation directives could also improve by considering monitoring sample designs that include this hypothesis, helping to establish complete and detailed mercury contamination scenarios.

Despite considerable progress in ecotoxicology, it has become clear that this discipline cannot answer its central questions, such as, “What are the effects of toxicants on biodiversity?” and “How the ecosystem functions and services are affected by the toxicants?”. We argue that if such questions are to be answered, a paradigm shift is needed. The current bottom-up approach of ecotoxicology that implies the use of small-scale experiments to predict effects on the entire ecosystems and landscapes should be merged with a top-down macroecological approach that is directly focused on ecological effects at large spatial scales and consider ecological systems as integral entities. Analysis of the existing methods in ecotoxicology, ecology, and environmental chemistry shows that such integration is currently possible. Therefore, we conclude that to tackle the current pressing challenges, ecotoxicology has to progress using both the bottom-up and top-down approaches, similar to digging a tunnel from both ends at once.

In agroecosystems, organisms may regularly be exposed to anthropogenic stressors, e.g. pesticides. Species' sensitivity to stress depends on toxicity, life-history, and landscape structure. We developed an individual-based model of an isopod, Asellus aquaticus, to explore how timing of stress events affects population dynamics in a seasonal environment. Furthermore, we tested the relevance of habitat connectivity and spatial distribution of stress for the recovery of a local and total population. The simulation results indicated that population recovery is mainly driven by reproductive periods. Furthermore, high habitat connectivity led to faster recovery both for local and total populations. However, effects of landscape structure disappeared for homogeneously stressed populations, where local survivors increased recovery rate. Finally, local populations recovered faster, implying that assessing recovery in the field needs careful consideration of spatial scale for sampling. We emphasize the need for a coherent definition of recovery for more relevant ecosystem risk assessment and management.

Warm season (May–October) chloride concentrations were assessed in stream habitats of freshwater mussel species at risk in southern Ontario, Canada. Significant increases in concentrations were observed at 96% of 24 long-term (1975–2009) monitoring sites. Concentrations were described as a function of road density indicating an anthropogenic source of chloride. Linear regression showed that 36% of the variation of concentrations was explained by road salt use by the provincial transportation ministry. Results suggest that long-term road salt use and retention is contributing to a gradual increase in baseline chloride concentrations in at risk mussel habitats. Exposure of sensitive mussel larvae (glochidia) to increasing chloride concentrations may affect recruitment to at risk mussel populations.

High levels of polybrominated diphenyl ethers (PBDEs) have been extensively reported in urban areas and at e-waste recycling sites in coastal China. However, data are scarce in northern China and are not available in rural areas at all. In addition, it is often believed that air concentrations in rural areas are lower than those in urban areas without distinguishing rural residential areas and open fields. In this study, air samples were collected at 17 sites covering urban and rural (residential and open field) areas in northern China using active samplers. With BDE-209 dominated in all congeners, the average concentrations of BDE-209 (41 ± 72 pg/m³) and other 13 PBDEs (16 ± 12 pg/m³) were significantly lower than those found in south China, such as in Guangzhou or Hong Kong. On average, the total PBDE concentrations at the urban sites were 2.2 and 2.9 times of those at the rural residential and field sites, respectively.

Environmental contamination by arsenic constitutes a problem in many countries, and its accumulation in food crops may pose health complications for humans. Reactive oxygen species (ROS) and reactive nitrogen species (RNS) are involved at various levels in the mechanism of responding to environmental stress in higher plants. Using Arabidopsis seedlings exposed to different arsenate concentrations, physiological and biochemical parameters were analyzed to determine the status of ROS and RNS metabolisms. Arsenate provoked a significant reduction in growth parameters and an increase in lipid oxidation. These changes were accompanied by an alteration in antioxidative enzymes and the nitric oxide (NO) metabolism, with a significant increase in NO content, S-nitrosoglutathione reductase (GSNOR) activity and protein tyrosine nitration as well as a concomitant reduction in glutathione and S-nitrosoglutathione (GSNO) content. Our results indicate that 500 μM arsenate (AsV) causes nitro-oxidative stress in Arabidopsis, being the glutathione reductase and the GSNOR activities clearly affected.

Root crops, carrot and celeriac, were exposed to atmospheric deposition in a polluted versus reference area. An effect was observed on the As, Cd and Pb concentrations of the leaves and the storage organs. The concentrations in the whole storage organs correlated well with atmospheric deposition, which shows that they even could be used for biomonitoring. Nevertheless, leaves remain much more appropriate. The results revealed also a significant increase of the As and Cd concentration in the consumable part of the storage organs as a function of their atmospheric deposition. As such the experiments allowed deriving regression equations, useful for modeling the atmospheric impact of trace elements on the edible parts of root crops. For Pb, however, there was hardly any significant impact on the inner parts of the storage organs and as such the transfer of Pb in the food chain through root crops can be considered to be negligible.

The aim of the present study was to improve the cause–effect relationship between toxicant exposure and chironomid mouthpart deformities, by linking induction of mouthpart deformities to contaminated field sediments, metal mixtures and a mutagenic polycyclic aromatic compound metabolite (acridone). Mouthpart deformities in Chironomus riparius larvae were induced by both the heavy metal mixture and by acridone. A clear correlation between metal concentrations in the sediment and deformities incidence was only observed when the contaminated field sediments were left out of the analysis, probably because these natural sediments contained other toxic compounds, which could be responsible for a higher incidence of deformities than predicted by the measured metal concentrations only. The present study clearly improved the cause–effect relationship between toxicant exposure and the induction of mouthpart deformities. It is concluded that the incidence of mouthpart deformities may better reflect the potential toxicity of contaminated sediments than chemical analysis.