Selenium (Se) is an essential micronutrient for animals with a relatively narrow margin between essentiality and toxicity. To evaluate Se removal efficiency by a constructed wetland treatment system and its potential eco-risk, a floating-leaved macrophyte system was constructed, consisting of three main trophic levels. Over 21-d treatment, water Se concentration was gradually reduced by 40.40%, while 24.03% and 74.41% of the removed Se were found in the plant Nymphoides sp. and sediment, respectively. Among plant tissues, roots accumulated the highest Se level, although the greatest total Se was found in stems, followed by leaves, roots and rhizomes. X-ray absorption spectroscopy revealed that 82.65% of the absorbed selenite by the plants was biotransformed to other forms, as organo-Se species accounted for 45.38% of the Se retained in the sediment, which was primarily responsible for the entry of Se into the detritus food chain. The proportion of organo-Se compounds increased with trophic levels from sediments to fish, indicating, instead of direct uptake of selenite, the food chain transfer and biotransformation of Se may serve as a key exposure route for Se in aquatic organisms. When exposed to organo-Se compounds, i.e., SeCys and SeMet, the plants, shrimp and fish tended to accumulate more Se. However, the greater trophic transfer factor was obtained for selenate, leading to higher Se levels accumulated in fish. Overall, in addition to key mechanisms involved in Se removal, our research also provides a much better understanding of the potential eco-risk that may be posed by the floating-leaved plant system for bioremediation of Se via food chain transfer and biotransformation, paving the way for a low eco-toxic treatment system for Se remediation.

Lipophilic marine algal toxins (LMATs) pose a potential threat to the health of marine shellfish consumers and marine breeding industries. In this study, LMATs in dissolved phases (DP) and particulate phases (PP) in the seawater of Jiaozhou Bay were accurately determined over four seasons to understand their composition, level, phase partitioning, spatiotemporal variation, and potential sources in aquatic environments of a typical semi-closed mariculture bay. Various LMATs, such as okadaic acid (OA), dinophysistoxin-1 (DTX1), dinophysistoxin-2 (DTX2), gymnodimine (GYM), 13-desmethyl spirolide C (SPX1), pectenotoxin-2 (PTX2), pectenotoxin-2 seco acid (PTX2 SA), and pectenotoxin-11 (PTX11), were detected in DP and PP; of these, OA and PTX2 were the dominant LMATs in DP and PP, respectively. The average proportion of ΣLMATs in DP (97.5%) was significantly higher than that in PP (2.5%), which indicates that LMATs are predominantly partitioned into DP. The total concentrations of LMATs in DP ranged from 4.16 ng/L to 23.19 ng/L (mean, 13.35 ng/L) over four seasons. The highest levels of LMATs in DP and PP were found in summer (mean, 16.71 ng/L) and spring, respectively, while the maximum variety of LMATs was found in autumn. This result suggests that seasonal changes could influence the composition, concentration, and phase partitioning of LMATs in aquatic environments of a coastal semi-closed mariculture bay. ΣLMAT concentrations were higher in the western region than in the eastern region of the bay, where shellfish may have a greater risk of exposure. Dinophysis acuminata, Dinophysis fortii, and Prorocentrum minimum were the potential sources of LMATs in the aquaculture seawater. Overall, various LMATs occurred in the semi-closed mariculture bay, and the persistence and bioavailability of these toxins in aquaculture seawater should be determined in future research.

Sclerotinia stem rot (SSR), a soil-borne plant disease, cause the yield loss of oilseed rape. Selenium (Se), a beneficial element of plant, improves plant resistance to pathogens, and regulates microbial communities in soil. Soil microbial communities has been identified to play an important role in plant health. We studied whether the changes in soil microbiome under influence of Se associated with oilseed rape health. SSR disease incidence of oilseed rape and soil biochemical properties were investigated in Enshi district, “The World Capital of Selenium”, and soil bacterial and fungal communities were analyzed by 16S rRNA and ITS sequencing, respectively. Results showed that Se had a strong effect on SSR incidence, and disease incidence inversely related with plant Se concentration. Besides, soil Se enhanced the microbiome diversities and the relative abundance of PGPR (plant growth promoting rhizobacteria), such as Bryobacter, Nitrospirae, Rhizobiales, Xanthobacteraceae, Nitrosomonadaceae and Basidiomycota. Furthermore, Soil Se decreased the relative abundance of pathogenic fungi, such as Olpidium, Armillaria, Coniosporium, Microbotryomycetes and Chytridiomycetes. Additionally, Se increased nitrogen metabolism, carbohydrate metabolism and cell processes related functional profiles in soil. The enrichment of Se in plants and improvement of soil microbial community were related to increased plant resistance to pathogen infection. These findings suggested that Se has potential to be developed as an ecological fungicide for biological control of SSR.

Conjunctivitis has hazardous effects on patients’ quality of life through influencing school performance, work productivity, and daily activities such as driving. However, limited evidence is available on the contributory role of air pollution on conjunctivitis, particularly in China.We obtained data of 81,351 conjunctivitis outpatients from the largest comprehensive hospitals of four cities, China, between Jan 1, 2013 and Dec 31, 2014. Data on air pollutants, including particulate matter ≤2.5 μm in diameter (PM₂.₅), particulate matter ≤10 μm in diameter (PM₁₀), nitrogen dioxide (NO₂), ozone (O₃) and sulphur dioxide (SO₂) were collected from China National Environmental Monitoring Centre. Conjunctivitis outpatient visits were linked with air pollution concentrations by the visiting dates. A time-stratified case-crossover design with conditional logistic regression model was used to examine the effect of short-term exposure to air pollution on conjunctivitis outpatient visits.We found that the associations between air pollutants (per 10 μg/m³ increase) and hospital outpatient visits for asthma were [odds ratios (ORs) and 95% confidence intervals]: 1.004(1.002–1.007) for PM₂.₅, 1.004 (1.002–1.005) for PM₁₀, 1.012(1.005–1.020) for NO₂, 1.006 (1.001–1.011) for SO₂, and 1.007 (1.003–1.010) for O₃, respectively at lag0 day. Outpatients aged 35–64 years showed significant associations with exposure to PM₂.₅ (1.005, 1.001–1.010), PM₁₀ (1.005, 1.002–1.008), NO₂ (1.014, 1.003–1.026), and O₃ (1.005, 1.000–1.011), while those aged 15–34 years showed significant associations with exposure to O₃ (1.010, 1.004–1.017).Short-term exposure to air pollution has impacts on outpatient visits for conjunctivitis in China. This study suggests that improving air quality could protect eye health.

The concentrations of heavy metals and other components in road dust from a Polish coal mining district were investigated. The sample was split into eight size fractions ranging from <5 μm to 1–2 mm applying the combined classification procedure of dry sieving and air classification. For most elements, significantly higher concentrations were found in the finest size fractions. In combination with the mass fractions of the various size fractions the concentrations of the components were calculated for this road dust assuming different upper size limits. The results demonstrate the important influence of the upper size limit applied on the composition of road dust. An analysis of the composition of road dust by particle size, instead of analysing whole road dust samples, proves to have several advantages. On the one hand, a reliable comparison of the results with the concentration data available in the literature is possible and on the other hand, the results can be used in assessments, for example resuspension or wash-off by rainfall, which require different upper size limits.Upper size limit applied in road dust sampling significantly influences the results. Combined sieving and air classification sample preparation procedure allows flexible use of the results.

The effluent stream of the anaerobic digestion processes, the digestate, accommodates high residual organic content that needs to be further treated before discharge. Anaerobic treatment of digestate would not only reduce the residual organic compounds in digestate but also has a potential to capture the associated biogas. High-rate anaerobic reactor configurations can treat the waste streams using lower hydraulic retention times which requires less footprint opposed to the conventional completely stirred tank reactors. This study investigated the high-rate anaerobic treatment performance and the associated biogas capture from the digestate of a manure mixture composed of 90% laying hen and 10% cattle manures in fixed-film reactors. The results indicated that it was possible to reduce total chemical oxygen demand content of the digestate by 57–62% in 1.3–1.4 days of hydraulic retention time. The corresponding biogas yields obtained were in the range of 0.395–0.430 Lbiogas/g VSadded which were found to be comparable to many raw feedstocks. Moreover, significant total phosphorus reduction (36–47%) and greenhouse gas capture (over 14.5–18.1 tCO2e/d per m3 digestate) were also recorded in the anaerobic fixed-film reactors.

In the present work, we analyzed the concentration patterns of 20 Polycyclic Aromatic Hydrocarbons (PAHs) in 25 surface sediments and 11 sediment cores from the northern part of Taihu Lake, China. Three of the cores were dated based on ¹³⁷Cs activity for the deposition age of the sediment. The spatial distributions of the PAH concentrations show that the inflow rivers into Zhushan Bay and Meiliang Bay were the main pathway for PAHs and sediment input to the northern part of the lake. This results in substantially higher PAH concentrations (up to 5000 ng/g) and sedimentation rates (higher than the average of 3–4 mm/a) in the area close to the river outlets. In addition, results also show that PAH concentrations in the sediments considerably increased from the early 1960s, but the decreasing concentrations in the upper layers of the sediment could be attributed to the introduction of measures on environmental improvement from ca. 2000. There were both anthropogenic and biogenic origins of perylene in the lake sediments, which were distinguished based on spatial distribution patterns and also the concentration proportions of perylene to the sum of the 20 PAHs. In the cores collected close to river outlets, the concentration proportions of perylene typically range from 0.02 to 0.18 and there are significant positive linear correlations between the concentration of perylene and three anthropogenic PAHs (Benzo[a]pyrene, Benzo[e]pyrene, Pyrene), suggesting that perylene was dominated by anthropogenic input. However, the cores collected further away from the river outlets show the concentration proportions between 0.13 and 0.96, and present significant negative correlations or no correlations between perylene and the three PAHs, suggesting that perylene was mainly formed by biogenic activities. Furthermore, the different perylene sources accompanied with the location distributions imply that anthropogenic activities could inhibit its biogenic formation.

Storm water culverts are integral for U.S. public safety and welfare, and their mechanical failure can cause roadways to collapse. To repair these buried assets, ultraviolet (UV) light cured-in-place-pipes (CIPP) are being installed. Chemical emission and residual material left behind from the installation process was investigated in New York and Virginia, USA. Samples of an uncured resin tube and field-cured styrene-based resin CIPPs were collected and analyzed. Also collected were air and water samples before, during, and after installations. Chemicals were emitted into air because of the installation and curing processes. Particulates emitted into the air, water, and soil contained fiberglass, polymer, and contaminants, some of which are regulated by state-level water quality standards. The uncured resin tube contained more than 70 chemical compounds, and 19 were confirmed with analytical standards. Compounds included known and suspected carcinogens, endocrine disrupting compounds, hazardous air pollutants, and other compounds with little aquatic toxicity data available. Compounds (14 of 19 confirmed) were extracted from the newly installed CIPPs, and 11 were found in water samples. Aqueous styrene (2.31 mg/L), dibutyl phthalate (12.5 μg/L), and phenol (16.7 μg/L) levels exceeded the most stringent state water quality standards chosen in this study. Styrene was the only compound that was found to have exceed a 48 h aquatic toxicity threshold. Newly installed CIPPs contained a significant amount volatile material (1.0 to > 9.0 wt%). Recommendations provided can reduce chemical emission, as well as improve worksite and environmental protection practices. Recommended future research is also described.

Noise pollution in cities is mainly caused by the vehicular traffic but, depending on the place under assessment, it could be affected by the land use. For noise assessment and strategic noise mapping, the night period equivalent level (Lnight), which evaluates sleep disturbance, is one of the requirements of the European Directive 2002/49/EC to be presented for the equivalent time of one year. This research aims to find the influence of the land use in the weekdays stratification to improve the accuracy of the long-term noise level estimation for the night period. It is found that depending on the land use of the place under assessment, the weekdays temporal and spatial stratification could be affected by leisure activities. From a statistical analysis based on a clustering procedure of Lnight samples in 19 points, it is observed that both, temporal and spatial stratification depend on the intensity of the surrounding leisure activity, and not on traffic. Following these stratification criteria, a sampling method is presented that reduces by 47% the number of days needed to estimate the annual levels with respect to random sampling.