Bioturbation alters the properties of sediments and modifies contaminant bioavailability to benthic organisms. These naturally occurring disturbances are seldom considered during the assessment of sediment quality. We investigated how the presence (High bioturbation) and absence (Low bioturbation) of a strongly bioturbating amphipod within three different sediments influenced metal bioavailability, survival and bioaccumulation of metals to the bivalve Tellina deltoidalis. The concentrations of dissolved copper decreased and manganese increased with increased bioturbation. For copper a strong correlation was observed between increased bivalve survival (53–100%) and dissolved concentrations in the overlying water. Increased bioturbation intensity resulted in greater tissue concentrations for chromium and zinc in some test sediments. Overall, the results highlight the strong influence that the natural bioturbation activities from one organism may have on the risk contaminants pose to other organisms within the local environment. The characterisation of field-based exposure conditions concerning the biotic or abiotic resuspension of sediments and the rate of attenuation of released contaminants through dilution or readsorption may enable laboratory-based bioassay designs to be adapted to better match those of the assessed environment.

Elevated nitrogen (N) deposition impacts the structure and functioning of heathland ecosystems across Europe. Calluna plants under high N-inputs are very sensitive to secondary stress factors, including defoliation attacks by the heather beetle. These attacks result in serious damage or death of Calluna, its rapid replacement by grasses, and the subsequent loss of heathland. We know very little about the mechanisms that control the populations and trigger outbreaks of the heather beetle, impeding proper management measures to mitigate the damage. We investigated the effects of N deposition on the relationships between the heather beetle, its host plant, and two arthropod predators at building (rejuvenated through fire) and mature heathlands. The study combines field manipulation experiments simulating a range of N deposition rates (0, 1, 2, 5 g N m−2 year−1 for 2 years, and 5.6 g N m−2 year−1 for 10 years), and food-choice laboratory experiments testing the preferences of adults and larvae of the heather beetle for N-treated Calluna plants, and the preferences of predators for larvae grown on plants with different N-content. The larvae of the heather beetle achieved the highest abundances after the long-term (10-year) addition of N at mature Calluna plots in the field. Contrary to the adults, the larvae foraged preferentially on the most N-rich Calluna shoots under laboratory conditions. Predators showed no aggregative numerical responses to the accumulation of heather beetle larvae at high N-input experimental plots. During the feeding trials, predators consumed a small number of larvae, both in total and per individual, and systematically avoided eating the larvae reared on high-N Calluna shoots. Our study showed that the most severe defoliation damage by the heather beetle is inflicted at the larval stage under prolonged availability of high-N inputs, and that arthropod predators might not act as effective regulators of the beetle's populations.

Road tunnels act like large laboratories; they provide an excellent environment to quantify atmospheric particles emission factors from exhaust and non-exhaust sources due to their known boundary conditions. Current work compares the High Volume, Dichotomous Stacked Filter Unit and Partisol Air Sampler for coarse, PM10 and PM2.5 particle concentration measurement and found that they do not differ significantly (p = 95%). PM2.5 fraction contributes 66% of PM10 proportions and significantly influenced by traffic (turbulence) and meteorological conditions. Mass emission factors for PM10 varies from 21.3 ± 1.9 to 28.8 ± 3.4 mg/vkm and composed of Motorcycle (0.0003–0.001 mg/vkm), Cars (26.1–33.4 mg/vkm), LDVs (2.4–3.0 mg/vkm), HDVs (2.2–2.8 mg/vkm) and Buses (0.1 mg/vkm). Based on Lawrence et al. (2013), source apportionment modelling, the PM10 emission of brake wear (3.8–4.4 mg/vkm), petrol exhaust (3.9–4.5 mg/vkm), diesel exhaust (7.2–8.3 mg/vkm), re-suspension (9–10.4 mg/vkm), road surface wear (3.9–4.5 mg/vkm), and unexplained (7.2 mg/vkm) were also calculated. The current study determined that the combined non-exhaust fleet PM10 emission factor (16.7–19.3 mg/vkm) are higher than the combined exhaust emission factor (11.1–12.8 mg/vkm). Thus, highlight the significance of non-exhaust emissions and the need for legislation and abatement strategies to reduce their contributions to ambient PM concentrations.

Exposure to particulate matter (PM) pollution in cities and urban canyons can be harmful to the exposed population. However, the underlying mechanisms that lead to health effects are not yet elucidated. It is postulated that exposure to repeated, small, environmentally relevant concentrations can affect lung homeostasis. This study examines the impact of repeated exposures to urban PM on mouse lungs with focus on inflammatory and oxidative stress parameters. Aqueous extracts from collected urban PM were administered to mice by 5 repeated intra-tracheal instillations (IT). Multiple exposures, led to an increase in cytokine levels in both bronchoalveolar lavage fluid and in the blood serum, indicating a systemic reaction. Lung mRNA levels of antioxidant/phase II detoxifying enzymes decreased by exposure to the PM extract, but not when metals were removed by chelation. Finally, disruption of lung tissue oxidant-inflammatory/defense balance was evidenced by increased levels of lipid and protein oxidation. Unlike response to a single IT exposure to the same dose and source of extract, multiple exposures result in lung oxidative damage and a systemic inflammatory reaction. These could be attributed to compromised capacity to activate the protective Nrf2 tissue defense system. It is suggested that water-soluble metals present in urban PM, potentially from break and tire wear, may constitute major drivers of the pulmonary and systemic responses to multiple exposure to urban PM.

Polybrominated diphenyl ethers (PBDEs) are persistent and toxic organic pollutants, causing hazardous to ecosystems and human health but are difficult to remove from contaminated environments. The mechanism and kinetics of a Chlorella isolate to remove BDE-47 were investigated. This species isolated from the influent of wastewater treatment plants in Hong Kong was PBDE tolerant. More than 80% of BDE-47 was removed in short- and long-term experiments lasting 1 h and 7 days, respectively. The dominant removal process was adsorption on cell surfaces, with 73% of the spiked BDE-47 removed within five minutes of exposure. As the exposure prolonged, the adsorption became saturated. BDE-47 on cell surfaces was then gradually taken up into cells. At the end of the 7-day exposure, 17% of the spiked BDE-47 was within cells, while 27% was metabolized. Four metabolites, including BDE-28, 6-OH- and 5-OH-BDE-47, and 6-MeO-BDE-47, were produced from the debromination, hydroxylation and methoxylation of BDE-47. The removal kinetics of BDE-47 by freshwater microalgae could be explained by the multi-compartmental adsorption-uptake-metabolism model developed in this study.

Biosolids are extensively used in agriculture as fertilizers while offering a practical solution for waste disposal. Many pharmaceutical and personal care products (PPCPs), such as triclosan and triclocarban, are enriched in biosolids. Biosolid amendment changes soil physicochemical properties, which may in turn alter the persistence of PPCPs and hence the risk for secondary contamination such as plant uptake. To delineate the effect of biosolids on PPCPs persistence, triclosan and triclocarban were used as model compounds in this study and their sorption (Kd) and persistence (t1/2) were determined in different soils before and after biosolid amendment. Biosolids consistently increased sorption of triclosan and triclocarban in soil. The Kd of triclosan increased by 3.9–21 times following amendment of a sandy loam soil with biosolids at 2–10%. The persistence of both compounds was prolonged, with t1/2 of triclosan increasing from 10 d in the unamended soil to 63 d after biosolid amendment at 10%. The relationship between t1/2 and Kd was further examined through a meta-analysis using data from this study and all relevant published studies. A significant linear relationship between t1/2 and Kd was observed for triclosan (r2 = 0.69, p < 0.01) and triclocarban (r2 = 0.38, p < 0.05) in biosolid-amended soils. On the average, when biosolid amendment increased by 1%, t1/2 of triclosan was prolonged by 7.5 d, while t1/2 of triclocarban was extended by 4.7 d. Therefore, biosolid amendment greatly enhances persistence of triclosan and triclocarban, likely due to enhanced sorption or decreased chemical bioavailability. This finding highlights the importance to consider the effect of biosolids when evaluating the environmental risks of these and other biosolid-borne PPCPs.

Adsorption of aromatic compounds, including polycyclic aromatic hydrocarbons, nitrobenzenes, phenols, and anilines, on a bamboo biochar produced at 700 °C (Ba700) was investigated with the mechanism discussion by isotherm fitting using the Polanyi-theory based Dubinin–Ashtakhov (DA) model. Correlations of adsorption capacity (Q0) of organic compounds with their molecular sizes and melting points, as well as correlations of adsorption affinity (E) with their solvatochromic parameters (i.e., π* and αm), on the biochar, were developed and indicating that adsorption is captured by the pore filling mechanism and derived from the hydrophobic effects of organic compounds and the forming of π-π electron donor-acceptor (EDA) interactions and hydrogen bonding interactions of organic molecules with surface sites of the biochar. The effects of organic molecular sizes and melting points on adsorption capacity are ascribed to the molecular sieving effect and the packing efficiency of the organic molecules in the biochar pores, respectively. These correlations can be used to quantitatively estimate the adsorption of organic compounds on biochars from their commonly physicochemical properties including solvatochromic parameters, melting points and molecular cross-sectional area. The prediction using these correlations is important for assessing the unknown adsorption behaviors of new organic compounds and also helpful to guide the surface modification of biochars and make targeted selection in the environmental applications of biochars as adsorbents.

China has been embracing rapid motorization since the 1990s, and vehicles have become one of the major sources of air pollution problems. Since the late 1990s, thanks to the international experience, China has adopted comprehensive control measures to mitigate vehicle emissions. This study employs a local emission model (EMBEV) to assess China's first fifteen-year (1998–2013) efforts in controlling vehicles emissions. Our results show that China's total annual vehicle emissions in 2013 were 4.16 million tons (Mt) of HC, 27.4 Mt of CO, 7.72 Mt of NOX, and 0.37 Mt of PM2.5, respectively. Although vehicle emissions are substantially reduced relative to the without control scenarios, we still observe significantly higher emission density in East China than in developed countries with longer histories of vehicle emission control. This study further informs China's policy-makers of the prominent challenges to control vehicle emissions in the future. First, unlike other major air pollutants, total NOX emissions have rapidly increased due to a surge of diesel trucks and the postponed China IV standard nationwide. Simultaneous implementation of fuel quality improvements and vehicle-engine emission standards will be of great importance to alleviate NOX emissions for diesel fleets. Second, the enforcement of increasingly stringent standards should include strict oversight of type-approval conformity, in-use complacence and durability, which would help reduce gross emitters of PM2.5 that are considerable among in-use diesel fleets at the present. Third, this study reveals higher HC emissions than previous results and indicates evaporative emissions may have been underestimated. Considering that China's overall vehicle ownership is far from saturation, persistent efforts are required through economic tools, traffic management and emissions regulations to lower vehicle-use intensity and limit both exhaust and evaporative emissions. Furthermore, in light of the complex technology for emerging new energy vehicles, their real-world emissions need to be adequately evaluated before massive promotion.

Discharge of antimicrobial residues and resistant bacteria in hospital effluents is supposed to have strong impacts on the spread of antibiotic resistant bacteria in the environment. This study aimed to characterize the effluents of the Gabriel Montpied teaching hospital, Clermont-Ferrand, France, by simultaneously measuring the concentration of ciprofloxacin and of biological indicators resistant to this molecule in biofilms formed in the hospital effluent and by comparing these data to ciprofloxacin consumption and resistant bacterial isolates of the hospital. Determination of the measured environmental concentration of ciprofloxacin by spot sampling and polar organic chemical integrative (POCIS) sampling over 2 weeks, and comparison with predicted environmental concentrations produced a hazard quotient >1, indicating a potential ecotoxicological risk. A negative impact was also observed with whole hospital effluent samples using the Tetrahymena pyriformis biological model.During the same period, biofilms were formed within the hospital effluent, and analysis of ciprofloxacin-resistant isolates indicated that Gamma-Proteobacteria were numerous, predominantly Aeromonadaceae (69.56%) and Enterobacteriaceae (22.61%). Among the 115 isolates collected, plasmid-mediated fluoroquinolone-resistant genes were detected, with mostly aac(6′)-lb-cr and qnrS. In addition, 60% of the isolates were resistant to up to six antibiotics, including molecules mostly used in the hospital (aminosides and third-generation cephalosporins).In parallel, 1247 bacteria isolated from hospitalized patients and resistant to at least one of the fluoroquinolones were collected. Only 5 of the 14 species identified in the effluent biofilm were also found in the clinical isolates, but PFGE typing of the Gram-negative isolates found in both compartments showed there was no clonality among the strains.Altogether, these data confirm the role of hospital loads as sources of pollution for wastewater and question the role of environmental biofilms communities as efficient shelters for hospital-released resistance genes.

Ontario is Canada’s provincial leader in wind energy, with over 4000 MW of installed capacity supplying approximately five percent of the province’s electricity demand. Wind energy is now one of the fastest-growing sources of renewable power in Canada and many other countries. However, its possible negative impact on population health, as a new source of environmental noise, has raised concerns for people living in proximity to wind turbines (WTs). The aims of this study were to assess the effect of individual differences and annoyance on the self-reported general health and health-related quality of life (QOL) of nearby residents, using a pre- and post-exposure design. Prospective cohort data were collected before and after WT operations, from the individuals (n = 43) in Ontario, Canada. General health and QOL metrics were measured using standard scales, such as SF12, life satisfaction scales developed by Diener (SWLS) and the Canadian Community Health Survey (CCHS-SWL). The mean values for the Mental Component Score of SF12 (p = 0.002), SWLS (p < 0.001), and CCHS-SWL (p = 0.044) significantly worsened after WT operation for those participants who had a negative attitude to WTs, who voiced concerns about property devaluation, and/or who reported being visually or noise annoyed.