Few studies have reported the association between greenspace and academic performance at school level. We examined associations between both residential and school greenspace and individual school grades in German adolescents.German and maths grades from the latest school certificate, residential and school greenspace, and covariates were available for 1351 10 and 15 years old Munich children and 1078 Wesel children from two German birth cohorts – GINIplus and LISA. Residential and school greenspace was assessed by the Normalized Difference Vegetation Index (NDVI), tree cover, and (in Munich only) proportion of agricultural land, forest, and urban green space in 500-m and 1000-m circular buffers. Longitudinal associations between each exposure-outcome pair were assessed by logistic mixed effects models with person and school as random intercepts and adjusted for potential confounders.No associations were observed between any of the greenspace variables and grades in Wesel children. Several statistically significant associations were observed with German and maths grades in Munich children, however associations were inconsistent across sensitivity analyses.There is no evidence of an association of higher greenspace at residence, school or combined with improved academic performance in German adolescents from the GINIplus and LISA longitudinal studies.

Sulfide-rich tailings produced by mineral processing are prone to oxidation and cause many pollution problems in the surrounding environment; therefore, this issue has become a focus of attention. The Tongling Shuimuchong tailings reservoir contains a large amount of sulfide minerals, especially pyrrhotite and pyrite. This reservoir features obvious oxidation in the surface layer, and the slab is very hard. Mineralogical and environmental geochemical analyses were performed on tailings with different degrees of oxidation in the Shuimuchong tailings reservoir to investigate the influence of the formation of the hard oxidized layer on environmental pollution in the tailings pond. The samples were first subjected to particle-size analysis. The shallow tailings were mainly composed of medium particle; the proportions of coarse particle and fine tailings particles were equal; and the proportions of clay and silt were less than those of the other size fractions. Mineralogical analysis showed that pyrrhotite and pyrite were replaced by residual structures in the oxide layer. The secondary minerals goethite, hematite and jarosite were attached to the edges and fractures of sulfide minerals. The samples were geochemically analyzed to determine the total concentrations of 5 elements, the pH and the major anions. The maximum SO₄²⁻ concentrations of 33,970 and 32,749 mg/kg were observed at a depth of 40 cm in profiles 1 and 2, respectively. Metal sulfide mineral oxidation in the tailings lowered the pH of the materials to values less than 4. The concentration of HCO₃⁻ (122–635 mg/kg) in the tailings samples was very low, and the concentration of CO₃²⁻ was zero. As (53.2–133.7 mg/kg), Pb (24.2–307.5 mg/kg) and Hg (0.03–0.06 mg/kg) were concentrated in the highly oxidized layer at the surface; the Cd content (0.23–10.5 mg/kg) increased with decreasing oxidation degree of the tailings; and the Cr content (38.0–54.9 mg/kg) fluctuated around a certain value.

Data from National Health and Nutrition Examination Survey for 2013–2016 were used to compare observed levels of cadmium, lead, and total mercury in blood among US residents aged ≥12 years who were users of cigars, cigarettes, cigars and cigarettes, e-cigarettes and dual users of cigarettes and e-cigarettes. Total sample size available for analysis was 1139. Adjusted geometric means (AGM) among cigarette, cigar, e-cigarette, cigarette and cigar, and cigarette-e-cigarette users were comparable for blood cadmium lead, and total mercury. Cigar only users had lower AGM than cigar and cigarette users for total mercury (0.56 vs. 0.97 μg/L, p = 0.03). There is no evidence yet that can show concentrations of blood and urine cadmium, lead, and mercury among e-cigarette users are any different than among cigarette and/or dual users of cigarettes and e-cigarettes.

Heavy metal stress in soil accelerates the plant root exudation of organic ligands. The degradation of exudate ligands can be fundamental to controlling the complexation of heavy metals. However, this process remains poorly understood. Here, we investigated the relationship between the transformation of glycine, a representative amino acid exudate, and cadmium/lead mobility in soils. Two 48-h incubation experiments were conducted after glycine addition to the soils. Parameters related to glycine distribution and degradation, Cd/Pb mobility, and the formation of glycine-Cd complex were analyzed. Glycine addition gradually decreased the Cd and Pb mobility throughout the 48-h incubation. By the end of the experiment, the CaCl₂-extracted Cd and Pb concentrations decreased by 63.5% and 43.6%, respectively. The glycine mineralization was strong in the first 6 h, as indicated by a sharp decrease in CO₂ efflux rates from 10.04 ± 0.62 to 3.51 ± 0.07 mg C–CO₂ kg⁻¹ soil h⁻¹. The mineralization rates notably decreased after 6 h. The comparisons of dissolved organic carbon and hydrolyzable amino acid contents indicated that glycine mineralization in solution (95.6%) was much stronger than that in soil solids (49.3%). At the end of incubation, 0.22 mmol kg⁻¹ glycine remained in soil solids. The remaining glycine provided sufficient sorption sites for Cd²⁺ and Pb²⁺, resulting in enhanced metal fixation via complexation. Comparisons of zeta potentials supported the formation of the glycine-Cd complex. The Cd and Pb immobilization processes could be attributed to metal-glycine complex formation, sorption re-equilibrium, and glycine degradation. These findings emphasize that the biogeochemical processes of glycine, derived from root exudates or protein degradation products, increased the sorption of heavy metals to soils and thus reduced their toxicity to plants.

Pyrite weathering often occurs in nature and causes heavy metal ion pollution and acid mine drainage during the process. Humic acid (HA) is a critical natural organic material that can bind metal ions, thus affecting metal transfer and transformation. In this work, in situ electrochemical techniques combined with spectroscopic analysis were adopted to investigate the interfacial processes involved in pyrite weathering with/without HA. The results showed that the pyrite weathering mechanism with/without HA is FeS₂ → Fe²⁺ + 2S⁰ + 2e⁻. The presence of HA did not change the pyrite weathering mechanism, but HA adsorbs on the pyrite surface and inhibits the further transformation of sulfur. Furthermore, HA and Fe(II) ions can form complex at 45.0 °C. Increased concentration of HA, decreased HA solution acidity or decreased environmental temperature would all weaken the pyrite weathering, for the above conditions cause pyrite weathering to have a larger resistance of the double layer and a larger passive film resistance. Pyrite will release 73.7 g m⁻²·y⁻¹ Fe²⁺ to solution at pH 4.5, and the amount decreases to 36.8 g m⁻²·y⁻¹ in the presence of 100 mg/L HA. This study provides an in situ electrochemical method for the assessment of pyrite weathering.

The performance, nitrogen removal rate, microbial enzymatic activity and extracellular polymeric substances (EPS) of activated sludge were assessed under nickel (Ni(II)) stress. The organic matter and NH₄⁺-N removal efficiencies were stable at less than 10 mg/L Ni(II) and subsequently decreased with the increment of Ni(II) concentration from 10 to 30 mg/L. The specific oxygen uptake rate and dehydrogenase activity kept stable at less than 5 mg/L Ni(II) and then declined at 5–30 mg/L Ni(II). Both specific ammonia-oxidizing rate (SAOR) and specific nitrite-oxidizing rate (SNOR) decreased with the increment of Ni(II) concentration. The changing trends of ammonia monooxygenase and nitrite oxidoreductase activities were matched those of SAOR and SNOR, respectively. The nitrite-reducing rate and nitrate-reducing rate illustrated a similar variation tendency to the nitrite reductase activity and nitrate reductase activity, respectively. Ni(II) impacted on the production, chemical composition and functional group of EPS. The relation between the sludge volume index and the EPS production exhibited a better linear function with a negative slope, demonstrating that Ni(II) improved the sludge settleability despite of the increase of EPS production.

Elemental concentrations of ambient aerosols are commonly sampled over 12–24 h, and the low time resolution puts a great limit on current understanding about the temporal variations and source apportionment based on receptor models. In this work, hourly-resolved concentrations of eighteen elements in PM₂.₅ at an urban site in Nanjing, a megacity in Yangtze River Delta of east China, were obtained by using a Xact 625 ambient metals monitor from 12/12/2016 to 12/31/2017. The influence of traffic activities was clearly reflected by the spikes of crustal elements (e.g., Fe, Ca, and Si) in the morning rush hour, and the firework burning and sandstorm events during the sampling periods were tracked by sharp enrichment of Ba, K and Fe, Ca, Si, Ti in PM₂.₅, respectively. To evaluate the advantage of hourly-resolved elements data in identifying impacts from specific emission sources, positive matrix factorization (PMF) analysis was performed with the 1-h data set (PMF₁₋ₕ) and 23-h averaged data (PMF₂₃₋ₕ), respectively. The 4- and 6-factor PMF₂₃₋ₕ solutions had similar factor profiles and consistent factor contributions as the corresponding PMF₁₋ₕ solutions. However, due to the limit in inter-sample variability, PMF analysis with 23-h average data misclassified some major (e.g., K, Fe, Zn, Ca, and Si) and trace (e.g., Pb) elements in factor profiles, resulting in different absolute factor contributions between PMF₂₃₋ₕ and PMF₁₋ₕ solutions. These results suggested the use of high time-resolved data to obtain valid and robust source apportionment results.

Population growth, urbanization, environmental conditions and rapid development have caused particulate matter (PM) levels to rise above all national and international health standards during the last two decades in many South-East Asian countries. These PM levels needs to be reduced urgently as they increase the risk of cardiovascular and respiratory health problems for millions of people. Plants have shown to efficiently reduce PM in the air by accumulation on their leaves. In order to investigate which plant species accumulate most PM, we screened 49 common plant species for their PM accumulation capacity in one of the tropical cities with the highest PM concentrations of the world, Hanoi (Vietnam). Using this subset of plants, we tested if certain leaf characteristics (leaf hydrophilicity, stomatal densities and the specific leaf area) can predict the PM accumulation efficiency of plant species. Our results show that the PM accumulation capacity varies substantially among species and that Muntingia calabura accumulated most PM in our subset of plants. We observed that plants with hydrophilic leaves, a low specific leaf area and a high abaxial stomatal density accumulated significantly more PM. Plants with these characteristics should be preferred by urban architects to reduce PM levels in tropical environments.

The dissipation of famoxadone as well as the behaviour of its metabolites in environmental samples such as water and soil is a major concern. In this study, the dissipation of the target compound in both matrices was carried out applying an analytical method based on ultra-high performance liquid chromatography coupled to Orbitrap mass spectrometry (UHPLC-Orbitrap-MS). The dissipation of famoxadone was monitored over a period of 100 days after the plant protection product, Equation Pro®, was administered to the target matrices. This study was performed at two doses, normal and double in the case of soils and fivefold instead of double dose in water. The concentration of famoxadone steadily decreased during the monitoring period in both matrices. Half-life (DT₅₀) values were lower than 30 days in most cases except for loam soils, for which it was 35 days. Therefore, persistence of this pesticide in both matrices was low. Famoxadone metabolites such as IN-KF015 ((5RS)-5-methyl-5-(4-phenoxyphenyl)-1,3- oxazolidine-2,4-dione) and IN-JS940 ((2RS)-2-hydroxy-2-(4- phenoxyphenyl)propanoic acid) were detected in both matrices and their concentration increased while the concentration of the parent compound decreased. Metabolite IN-JS940 was the compound detected at highest concentration for both matrices. In water the maximum concentration was 20% of the initial famoxadone content and in soils it was 50% of initial famoxadone content. In addition, another metabolite, IN-MN467 ((5RS)-5-methyl-3-[(2-nitrophenyl)amino]- 5-(4-phenoxyphenyl)-1,3-oxazolidine-2,4-dione), was detected in soils, following the same behaviour as the other metabolites. These results provided ample information about the behaviour of metabolites and the necessity of knowing their toxicity in both matrices in order to detect possible risks for living beings.

Rapid development of Bohai and Yellow Sea Economic Rim has led to the concern of emerging contamination of marine environments. This study investigated the spatial distribution of antibiotic resistance genes (ARGs) in Bohai and Yellow Sea areas. A large scale sampling from Bohai Sea, Yellow Sea and the major cities along the coastline from the mouth of Yalu River to the Yangtze River was performed. The spatial distribution of target ARGs based on the absolute abundances was in the trend of river water ≈ coastal water > the Bohai Sea > the Yellow Sea, inshore > offshore and inner bay > bay mouth. The total absolute abundances of selected ARGs in the coastal waters (1.23 × 10⁴–3.94 × 10⁵ copies/mL) were about 1–4 orders of magnitude higher than those in the sea (21.1–8.00 × 10³ copies/mL). The abundances of ARGs fluctuated greatly in the Yellow Sea and the coastal areas. Sulfonamide resistance genes hold the highest abundances in the Bohai and Yellow Sea (up to 2.13 × 10³ copies/mL of sul1 and 6.23 × 10³ copies/mL of sul2), followed by tetracycline and quinolone resistance genes, while qnrA hold the highest abundances in coastal areas (up to 3.66 × 10⁵ copies/mL). The distribution coefficients of target genes between sediments and corresponding water samples were more than 1.0 in the majority of different aquatic systems. According to the principle component analysis and redundancy analysis, water samples collected from the sea clustered together while those from the coastal zone and rivers were separated. Ammonium and nitrate played important roles in the distribution and variation of ARGs. Co-occurrence network analysis revealed that the potential multi-antibiotics resistant bacteria were detected with higher abundances in the Yellow Sea than in the Bohai Sea. These observations provided a comprehensive new insight into the pollution status of ARGs in the Bohai and Yellow Sea areas.