Microplastics (MPs) represent a matter of growing concern for the marine environment. Their ingestion has been documented in several species worldwide, but the impact of specific anthropogenic activities remains largely unexplored. In this study, MPs were characterized in different benthic fish sampled after 2.5 years of huge engineering operations for the parbuckling project on the Costa Concordia wreck at Giglio Island. Fish collected in proximity of the wreck showed a high ingestion of microplastics compared to both fish from a control area and values reported worldwide. Also the elevated percentage of nylon, polypropylene lines and the presence of polystyrene are quite unusual for marine organisms sampled in natural field conditions, thus supporting the possible relationship of ingested microplastics with maritime operations during wreck removal. On the other hand, the use of transplanted mussels revealed a lower frequency of ingested MPs, and did not discriminate differences between the wreck and the control area. Some variations were observed in terms of typology and size of particles between surface- and bottom-caged mussels highlighting the influence of a different distribution of MPs along the water column. In conclusion, this study demonstrated that MPs pollution in the area of Costa Concordia was more evident on benthonic environment than on seawater column, providing novel insights on the possibility of using appropriate sentinel organisms for monitoring specific anthropogenic sources of MPs pollution in the marine environment.

The concentration and spatial distribution of microplastics in the Bay of Brest (Brittany, France) was investigated in two surveys. Surface water and sediment were sampled at nine locations in areas characterized by contrasting anthropic pressures, riverine influences or water mixing. Microplastics were categorized by their polymer type and size class. Microplastic contamination in surface water and sediment was dominated by polyethylene fragments (PE, 53–67%) followed by polypropylene (PP, 16–30%) and polystyrene (PS, 16–17%) microparticles. The presence of buoyant microplastics (PE, PP and PS) in sediment suggests the existence of physical and/or biological processes leading to vertical transfer of lightweight microplastics in the bay. In sediment (upper 5 cm), the percentage of particles identified by Raman micro-spectroscopy was lower (41%) than in surface water (79%) and may explain the apparent low concentration observed in this matrix (0.97 ± 2.08 MP kg−1 dry sediment). Mean microplastic concentration was 0.24 ± 0.35 MP m−3 in surface water. We suggest that the observed spatial MP distribution is related to proximity to urbanized areas and to hydrodynamics in the bay. A particle dispersal model was used to study the influence of hydrodynamics on surface microplastic distribution. The outputs of the model showed the presence of a transitional convergence zone in the centre of the bay during flood tide, where floating debris coming from the northern and southern parts of the bay tends to accumulate before being expelled from the bay. Further modelling work and observations integrating (i) the complex vertical motion of microplastics, and (ii) their point sources is required to better understand the fate of microplastics in such a complex coastal ecosystem.

The effects of wastewater irrigation and sewage sludge on the dissipation behavior of the fungicide benalaxyl and its primary metabolite benalaxyl acid in soil were studied on an enantiomeric level during a 148-day exposure experiment. Chiral separation and analysis of the two pairs of enantiomers were achieved using HPLC-MS/MS with a chiralpak IC chiral column. Benalaxyl decreased with half-life of 16.1 days in soil under tap water irrigation with preferential residue of S-benalaxyl. Benalaxyl acid was formed with great preference of R-enantiomer before 21 days while enriched in S-enantiomer afterwards. The degradation of benalaxyl was restrained by both wastewater and treated wastewater irrigation, but the enantioselectivity in S-benalaxyl residue was enhanced. Benalaxyl acid was also formed with similar enantioselectivity as in tap water irrigation. Sewage sludge could accelerate benalaxyl degradation with shorter half-life. Surprisingly, the enantioselectivity with preference degradation of S-enantiomer in sewage sludge was opposite to that in soil. More benalaxyl acid was generated with EF values always lower than 0.5 and remained longer in sewage sludge than in soil. A sterilization experiment indicated that the conversion of benalaxyl to benalaxyl acid and the enantioselectivity were determined by the microorganisms in soil or sewage sludge. Farming practices like wastewater irrigation and sewage sludge application might not only influence the fate of pesticide, but also the enantioselectivity of chiral pesticide enantiomers and thus the risks of pesticide residues posed to the environment.

Overburden and tailings materials from oil sands production were used as construction materials as part of a novel attempt to create a self-sustaining, peat accumulating fen-upland ecosystem. To evaluate the potential for elemental release from the construction materials, total elemental concentrations in the tailings sand, petroleum coke and peat used to construct a fen ecosystem were determined using microwave-assisted acid digestions and compared to a leaching experiment conducted under environmentally-relevant conditions. A comparison of solid phase to aqueous Na, Ca, S and Mg concentrations showed they were highly leachable in the materials. Given that the concentrations of these elements can affect plant community structure, it is important to understand their leachability and mobility as they migrate between materials used to construct the system. To that end, a mass balance of aqueous Na, Ca, S and Mg was conducted based on leaching experiments and materials analysis coupled with existing data from the constructed system. The data indicate that there is a large pool of leachable Na, Ca, S and Mg in the system, estimated at 27 t of Na, 14 t of Ca, 37.3 t of S and 8.8 t of Mg. Since recharge mainly drives the fen-upland system water regime, and discharge in the fen, evapo-accumulation of these solutes on the surface may occur.

Silvopastoral systems aim to enhance economic, cultural and social principles by sustainably combining forest management with agriculture. In these typically high-nitrogen (N) environments, plant species selection can profoundly influence N fluxes. For grazed pastures, plants may be exposed to urine patches that have received the equivalent of up to 1000 kg N ha−1. We aimed to determine the growth and N fluxes in three potential trees that may be used in silvopastoral systems: L. scoparium, K. robusta and P. radiata. Plants were grown in a greenhouse lysimeter experiment, with controlled irrigation and temperature and exposed to N at rates of 200 kg ha−1 equiv. for 15 weeks, followed by the addition of 800 kg ha−1 N equiv, to simulate a urine patch. Urea produced a positive growth response of all plant species. Treatments containing L. scoparium and K. robusta leached lower amounts of nitrate (NO3−) (2 kg ha−1 NO3−) compared to P. radiata (53 kg ha−1). Measurements of N2O over 20 days after the application of 800 kg N ha−1 indicated an inhibitory effect of L. scoparium and K. robusta on denitrification, hence loss of N via N2O. Both L. scoparium and K. robusta demonstrated that they have potential to reduce N-losses in silvopastural systems, while producing valuable biomass.

In this study, total mercury (THg) and methylmercury (MeHg) concentrations in muscles (leg and breast), organs (intestine, heart, stomach, liver) and blood were investigated for backyard chickens, ducks and geese of the Wanshan Mercury Mine, China. THg in poultry meat products range from 7.9 to 3917.1 ng/g, most of which exceeded the Chinese national standard limit for THg in meat (50 ng/g). Elevated MeHg concentrations (0.4–62.8 ng/g) were also observed in meat products, suggesting that poultry meat can be an important human MeHg exposure source. Ducks and geese showed higher Hg levels than chickens. For all poultry species, the highest Hg concentrations were observed in liver (THg: 23.2–3917.1 ng/g; MeHg: 7.1–62.8 ng/g) and blood (THg: 12.3–338.0 ng/g; MeHg: 1.4–17.6 ng/g). We estimated the Hg burdens in chickens (THg: 15.3–238.1 μg; MeHg: 2.2–15.6 μg), ducks (THg: 15.3–238.1 μg; MeHg: 3.5–14.7 μg) and geese (THg: 83.8–93.4 μg; MeHg: 15.4–29.7 μg). To not exceed the daily intake limit for THg (34.2 μg/day) and MeHg (6 μg/day), we suggested that the maximum amount (g) for chicken leg, breast, heart, stomach, intestine, liver, and blood should be 1384, 1498, 2315, 1214, 1081, 257, and 717, respectively; the maximum amount (g) for duck leg, breast, heart, stomach, intestine, liver, and blood should be 750, 1041, 986, 858, 752, 134, and 573, respectively; and the maximum amount (g) for goose leg, breast, heart, stomach, intestine, liver, and blood should be 941, 1051, 1040, 1131, 964, 137, and 562, respectively.

Benzene is a well-known occupational and environmental toxicant associated with cytopenia, which is characterized by a disorder in the peripheral blood cell counts. However, no effective preventive strategy has been developed yet to tackle the exposure to benzene in daily life. The aim of this study was to evaluate the protective effects of diallyl trisulfide (DATS) on benzene-induced haematopoietic damage and to reveal its potential mechanisms of action. In our study, male Sprague-Dawley rats were divided into six groups. Rats were administered with benzene (1.3 g/kg BW by gavage) to establish the benzene poisoning model, while the DATS treatment groups were treated with benzene plus DATS (15 mg/kg, 30 mg/kg, 45 mg/kg, respectively, by gavage) for 28 days. Our results demonstrated that the counts of peripheral blood WBC and RBC decreased to 31.0% and 79.2%, respectively, in the benzene poisoning model group compared to the control. However, blood cell counts were restored by DATS treatment (30 mg/kg, 45 mg/kg). The apoptosis rates of peripheral blood mononuclear cells (PBMCs) and bone marrow cells (BMCs) were increased to 274% and 284%, respectively, following benzene exposure. Furthermore, expression levels of Bcl-2, PI3K and p-Akt were downregulated and those of Bax were upregulated in both cell types. Moreover, the oxidative parameters (oxygen species, malonaldehyde) were significantly increased, while the non-enzymatic GSH/GSSG ratios and the activities of enzymatic antioxidants (superoxide dismutase, glutathione peroxidase and catalase) were decreased. Interestingly, DATS treatment can restore the WBC number by 267.1% and 304.8% while RBC number by 108.6% and 117.7% in 30,45 mg/k DATS treated groups. In summary, we demonstrated that benzene-induced cytopenia was related to the apoptosis of PBMCs and BMCs, and DATS treatment could prevent benzene-induced cytopenia by suppressing oxidative stress-mediated cell apoptosis via the PI3K/Akt pathway.

Probabilistic environmental quality criteria for Naphthalene (Nap), Phenanthrene (Phe), Fluoranthene (Flu), Pyrene (Pyr), Triclosan (TCS), Tributyltin (TBT), Chlorpyrifos (CPY), Diuron (DUR), γ-Hexaclorocyclohexane (γ-HCH), Bisphenol A (BPA) and 4-Nonylphenol (4-NP) were derived from acute toxicity data using saltwater species representative of marine ecosystems, including algae, mollusks, crustaceans, echinoderms and chordates. Preferably, data concerns sublethal endpoints and early life stages from bioassays conducted in our laboratory, but the data set was completed with a broad literature survey. The Water Quality Criteria (WQC) obtained for TBT (7.1·10⁻³ μg L⁻¹) and CPY (6.6· 10⁻³ μg L⁻¹) were orders of magnitude lower than those obtained for PAHs (ranging from 3.75 to 45.2 μg L⁻¹), BPA (27.7 μg L⁻¹), TCS (8.66 μg L⁻¹) and 4-NP (1.52 μg L⁻¹). Critical values for DUR and HCH were 0.1 and 0.057 μg L⁻¹ respectively. Within this context, non-selective toxicants could be quantitatively defined as those showing a maximum variability in toxicity thresholds (TT) of 3 orders of magnitude across the whole range of marine diversity, and a cumulative distribution of the TT fitting to a single log-logistic curve, while for selective toxicants variability was consistently found to span 5 orders of magnitude and the TT distribution showed a bimodal pattern. For the latter, protective WQC must be derived taking into account the SSD of the sensitive taxa only.

In epidemiological studies on the toxic effects of prenatal exposure to hexachlorobenzene (HCB), researchers report HCB concentrations, either as wet-weight or per lipid weight basis, in matrices like breast milk, and maternal and cord blood. Conversion of exposures across matrices is needed for comparisons of concentrations and dose effect across cohorts. Using data from a birth cohort study in eastern Slovakia, we derived the maternal blood to cord blood HCB concentration ratio utilizing measured concentrations in 1027 paired maternal and cord blood samples, on a per-lipid basis. In addition to data from the Slovak study, the maternal milk to maternal serum ratio was summarized from 23 published studies on partitioning of HCB between human milk lipid and blood lipid. We identified two distinct groups of milk:blood ratios, those ≤0.45 and those ≥0.85. We assumed that using partition ratios ≤0.45 will underestimate HCB exposure estimates. Taking into account this precautionary measure, we suggest a conversion ratio of 1.21, which is the median of the 16 ratios identified in our literature review. We consider our estimate as conservative and providing appropriate safety in risk analysis.

Environmental low-dose melamine exposure has been associated with urolithiasis risk in adults, but it is unclear if this exposure can cause early renal damage. This cross-sectional study investigated the association of this exposure and early renal damage in patients with calcium urolithiasis. We recruited patients diagnosed with upper urinary tract calcium urolithiasis from three hospitals in southwestern Taiwan between November 2010 and January 2015. All patients completed a structured questionnaire and provided one-spot urine samples for the measurement of melamine level and markers of early renal injury, including N-acetyl b-d-glucosaminidase (NAG), β2-microglobulin (β2-MG), and microalbumin. We used urinary melamine levels as an indicator of environmental melamine exposure. A total of 309 patients (mean age of 54.7 ± 12.8 years) were studied. Median urinary melamine level (μg/mmol Cr) was 1.26 (interquartile range 0.48–3.29). A significant and positive correlation was found between urinary melamine concentration and urinary NAG levels (Spearman correlation coefficient, r = 0.157, p = 0.006, n = 309). With urinary melamine levels categorized into quartiles, multivariate regression results showed the same relationship, particularly in those with first stone episode. In this group, patients with the highest quartile of urinary melamine concentration had a 3.95-fold risk (95% confidence interval = 1.43–10.94) of high NAG levels (dichotomized by median), compared to the lowest quartile after adjustment. No association was found between urinary melamine concentration and urinary microalbumin levels. In conclusion, urinary melamine is significantly associated with urinary marker of early renal tubular injury, NAG, in urolithiasis patients, especially ones with first stone episode.