Atrazine has been used on Chinese farmlands for a long time and over a wide range. The concentration of atrazine (1.86–1100 mg kg⁻¹) has exceeded the allowable limit in the soil (1.0 mg kg⁻¹), and concern is increasing about the potential harm to farmland soil. Four treatments (AT₀, AT₆, AT₁₀, AT₁₆) were established to reveal the effects of the long-term application of atrazine on soil health. The results showed a nonlinear regulation of the atrazine residue concentrations in the four treatments. The highest concentration of atrazine residue was in AT₆, at 167 mg kg⁻¹, and the lowest concentration of atrazine residue was in AT₁₆, at 102 mg kg⁻¹, but there was no significant difference between AT₁₀ and AT₁₆. The soil urease activity decreased significantly with the increase in the years of atrazine application, the saccharase and cellulase activities in the AT₆ were significantly higher than those observed in the other three treatments, the catalase activity gradually decreased with the increase in atrazine application years, and the activity in AT₆ was significantly higher than that in AT₁₆. A total of 238 genera were identified by Illumina MiSeq sequencing, and 28 dominant genera were screened. Atrazine significantly increased the relative abundance of Actinobacteria and contributed to the relative abundance of Rubrobacter, Blastococcus, Promicromonospora, Jiangella, Psychroglaciecola and Acetobacteraceae_uncultured, which exhibited significantly higher abundance in AT₁₆ than in AT₀. Although there were atrazine-degrading bacteria in the soil, and the atrazine residue decreased with the increase in application years, the concentration of the atrazine residue was still nearly 100 times higher than the allowable limit in the soil, which is a great threat to the soil health.

Mosaic loss of chromosome Y (mLOY) is the most common structure somatic event that related to increased risks of various diseases and mortality. Environmental pollution and genetic susceptibility were important contributors to mLOY. We aimed to explore the associations of polycyclic aromatic hydrocarbons (PAHs) exposure, as well as their joint effects with age, smoking, and genetic variants on peripheral blood mLOY. A total of 1005 male coke-oven workers were included in this study and their internal PAHs exposure levels of 10 urinary PAH metabolites and plasma benzo[a]pyrene-r-7,t-8,t-9,c-10-tetrahydotetrol-albumin (BPDE-Alb) adducts were measured. mLOY was defined by the median log R ratio(mLRR) of 1480 probes in male-specific region of chromosome-Y from genotyping array. We found that the PAHs exposure levels were linearly associated with mLOY. A 10-fold increase in urinary 1-hydroxynaphthalene (1-OHNa), 1-hydroxyphenanthrene (1-OHPh), 2-OHPh, 1-hydroxypyrene (1-OHP), ΣOH-PAHs, and plasma BPDE-Alb adducts could generate 0.0111, 0.0085, 0.0069, 0.0103, 0.0134, and 0.0152 decrease in mLRR-Y, respectively. Additionally, mLOY accelerated with age, smoking pack-years, and TCL1A rs1122138-C allele, and we observed the most severe mLOY among subjects carrying more than 3 of the above risk factors. Our results revealed the linear dose-effect associations between PAHs exposure and mLOY. Elder male smokers carrying rs1122138CC genotype were the most susceptible subpopulations to mLOY, who should be given protections for PAHs exposure induced chromosome-Y aberration.

Rapid urbanization is a global phenomenon that is increasingly exposing organisms to novel stressors. These novel stressors can affect diverse aspects of organismal function, including development of condition-dependent ornaments, which play critical roles in social and sexual selection. We investigated the relationship between metal pollution, proximity to roads, and carotenoid- and melanin-based plumage coloration in a common songbird, the great tit (Parus major). We studied populations located across a well-characterized metal pollution gradient and surrounded by roadway networks. Metal exposure and road-associated pollution could reduce carotenoid-based pigmentation by inducing oxidative stress or affecting habitat quality, but metals could also enhance melanin-based pigmentation, through effects on melanogenesis and testosterone concentrations. Using a large sample size (N > 500), we found that birds residing close to a point source for metals had reduced ultraviolet chroma, a component of carotenoid-based pigmentation. Moreover, birds with high feather metal concentrations had lower carotenoid chroma, hue, and ultraviolet chroma, with effects modified by age class. Birds residing closer to roads also had lower carotenoid chroma and hue. Melanin-based pigmentation showed high between-year repeatability, and no association with anthropogenic pollution. Results suggest that carotenoid-, but not melanin-, based pigmentation is negatively affected by multiple anthropogenic stressors. We are the first to demonstrate a negative association between roads and a plumage-based signaling trait, which could have important implications for sexual signaling dynamics in urban landscapes.

The effects of dike construction on the geomorphology and sedimentary processes of tidal flats were investigated using high-precision topographic profiling, short cores, and unmanned aviation vehicle (UAV)-assisted photogrammetry to understand their adverse consequences on the benthic ecosystem. Tidal flats at the south of Shinsi Island near one of the two sluice gates of the Saemangeum dike, display prominent morphologic features known as shelly sand ridges or cheniers (sensu Otvos, 2000) that have migrated landward about 5 m in a year. The tidal flats were dominated by erosion from winter to spring and by deposition during the remainder of the year except for the periods of heavy precipitation when tidal drainage channels became larger and deeper by headward erosion. With overall coarser-grained surface sediments, the presence of actively migrating wave-built cheniers are in stark contrast to muddy tidal flats with a monotonous morphology before the completion of the Saemangeum dike in 2006. Southeasterly waves reflected from the dike during winter to spring when north to northwesterly winds prevail account for the wave-induced onshore sediment transport and rapid morphologic changes in the tidal flats despite their location protected from offshore waves. The diversity and biomass of major macrofauna species tend to increase during rapid erosion and decrease during rapid deposition, highlighting the anthropogenic effect of dike-induced physical disturbance on the benthic ecosystem in the otherwise sheltered tidal flats.

The emergence of organophosphorus flame retardants and the efficient removal from aquatic environments have aroused increasing concerns. The Urea functionalized Fe₃O₄@LDH (Urea-Fe₃O₄@LDH) was prepared and used to adsorb triphenyl phosphate (tphp) for the first time. The tphp adsorption capacity was up to 589 mg g⁻¹, and the adsorption rate reached 49.9 mg g⁻¹ min⁻¹. Moreover, the influences of various environmental factors (pH, ionic strength and organic matter) on the tphp adsorption on the Urea-Fe₃O₄@LDH were investigated. The initial pH of the solution significantly affected the tphp adsorption, whereas the ionic strength and HA slightly affected the adsorption. The main adsorption mechanism was attributed to electrostatic interaction and π-π interaction. We believe that urea is one of excellent functional groups for the tphp adsorption removal and the materials with urea groups as the adsorbents exhibit good prospects in the future.

The present study investigated the effects of dietary iron (Fe) exposure on physiological performance and homeostatic regulation of trace metals during development (5–28 days post-fertilization; dpf) in zebrafish (Danio rerio). The results demonstrated that whole body Fe content was increased in 14 dpf larvae fed a high Fe diet. Cumulative mortality was also significantly elevated during exposure to the high Fe diet. Using droplet digital PCR, we observed that high Fe-exposed larvae exhibited an increase in mRNA levels of the Fe-storage protein ferritin, which appeared to be associated with the elevated level of whole body Fe content. Further, the results indicated that dietary Fe exposure induced transient changes in the mRNA expression levels of various metal transporters, including the iron transporter dmt1, and the zinc transporters zip8 and zip14. The expression of the epithelial Ca²⁺ channels (i.e., ecac) was also found to increase by high dietary Fe. Overall, our findings suggest that larval fish during the early nutritional transition period are sensitive to the effects of dietary Fe.

In Dhaka, Bangladesh, fine particulate matter (PM₂.₅) air pollution shows strong seasonal trends, with significantly higher mean concentrations during winter than during the monsoon (winter = 178.1 μg/m³ vs. monsoon = 30.2 μg/m³). Large-scale open burning of post-harvest agricultural waste across the Indo-Gangetic Plain is a major source of PM₂.₅ air pollution in northern India during the non-monsoon period. This study evaluates the extent to which the seasonal differences in PM₂.₅ pollution concentrations in Dhaka are accounted for by biomass-burning vs. fossil-fuel combustion sources. To assess this, an index was developed based on elemental potassium (K) as a marker for biomass particulate matter, after adjusting for soil-associated K contributions. Alternatively, particulate sulfur was employed as a tracer index for fossil-fuel combustion PM₂.₅. By simultaneously regressing total PM₂.₅ on S and adjusted K, the PM₂.₅ mass for each day was apportioned into: 1) fossil-fuels combustion associated PM₂.₅; 2) biomass-burning associated PM₂.₅; and, 3) all other PM₂.₅. The results indicated that fossil-fuel combustion contributed 21.6% (19.5 μg/m³), while biomass contributed 40.2% (36.3 μg/m³) of overall average PM₂.₅ from September 2013 to December 2017. However, the mean source contributions varied by season: PM₂.₅ in Dhaka during the monsoon season was dominated by fossil-fuels sources (44.3%), whereas PM₂.₅ mass was dominated by biomass-burning (41.4%) during the remainder of the year. The contribution to PM₂.₅ and each of its source components by transport of pollution into Dhaka during non-monsoon time was also evaluated by: 1) Conditional bivariate (CBPF) and pollution rose plots; 2) Concentration weighted trajectories (CWT), and; 3) NASA satellite photos to identify aerosol loading and fire locations on high pollution days. The collective evidence indicates that, while the air pollution in Dhaka is contributed to by both local and transboundary sources, the highest pollution days were dominated by biomass-related PM₂.₅, during periods of crop-burning in the Indo-Gangetic Plain.

Manganese (Mn) is an essential trace element, but an excess or accumulation can be toxic. Until now, few studies have examined the effects of maternal Mn level on the risk of spontaneous preterm birth (SPB). The aims of this study were to examine the association between maternal Mn level and the risk of SPB at the early stage of pregnancy, and investigate whether this association was modified by single nucleotide polymorphisms (SNPs) in genes of superoxide dismutase (SOD) and catalase (CAT). We conducted a nested case-control study in three maternal and child health care hospitals in Shanxi province, China, from December 2009 to December 2013. From an overall cohort of 4229 women, 528 were included in our study, including 147 cases of SPB and 381 controls. Maternal blood samples were collected during 4–22 gestational weeks. The maternal serum concentrations of Mn was measured using inductively coupled plasma–mass spectrometry. We found the maternal Mn concentration in the case group (median: 1.55 ng/mL) was significantly higher than that in the control group (median: 1.27 ng/mL). Compared to the lowest level, the SPB risk was significantly increased to 1.44 (95%CI: 0.60–3.43), 2.42 (95%CI: 1.06–5.55) and 2.46 (95%CI: 1.08–5.62) respectively for the second, third and fourth quartiles in first trimester, but not significant in second trimester or overall. When exposure to a high Mn level, women who with AA (6.36, 95%CI: 1.57–25.71) and AG (3.04, 95%CI: 1.59–5.80) of rs2758352, with CC (2.34, 95%CI: 1.31–4.18) of rs699473, and with GG (2.26, 95%CI: 1.22–4.16) of rs769214 were more likely to develop a SPB, but not among women with other genotypes. In conclusion, high maternal serum Mn level is associated with the increased SPB risk in first trimester, and the association is modified by maternal SNPs of SOD2, SOD3 and CAT.

In this study, the positive matrix factorization (PMF) source apportionment model was employed to quantify the contributions of airport activities to particle number concentrations (PNCs) at Amsterdam Schiphol. Time-resolved particle number size distributions in parallel with the concentrations of auxiliary variables, including gaseous pollutants (NOₓ and CO), black carbon, PM₂.₅ mass, and number of arrivals/departures were measured for 32 sampling days over a 6-month period near Schiphol airport to be used in the model. PMF results revealed that airport activities, cumulatively, accounted for around 79.3% of PNCs and our model segregated them into three major groups: (i) aircraft departures, (ii) aircraft arrivals, and (iii) ground service equipment (GSE) (with some contributions of local road traffic, mostly from airport parking lots). Aircraft departures and aircraft arrivals showed mode diameters <20 nm and contributed, respectively, to 46.1% and 26.7% of PNCs. The factor GSE/local road traffic, with a mode diameter of around 60–80 nm, accounted for 6.5% of the PNCs. Road traffic related mainly to the surrounding freeways was characterized with a mode diameter of 30–40 nm; this factor contributed to 18.0% of PNCs although its absolute PNCs was comparable with that of areas heavily impacted by traffic emissions. Lastly, urban background with a mode diameter at 150–225 nm, had a minimal contribution (2.7%) to PNCs while dominating the particle volume/mass concentrations with a contribution of 58.2%. These findings illustrate the dominant role of the airport activities in ambient PNCs in the surrounding areas. More importantly, the quantification of the contributions of different airport activities to PNCs is a useful tool to better control and limit the increased PNCs near the airports that could adversely impact the health of the adjacent urban communities.

This study forms the first basic assessment of microphytobenthos (MPB) dynamics in micro-estuaries and micro-outlets in southern Africa. It examines MPB community responses to environmental variables and further investigates MPB composition qualitatively across different micro-estuaries and micro-outlets over four seasons in a warm temperate region of the subcontinent. Combinations of multivariate analyses were used to explore similarities and differences in MPB communities between systems. Human-induced catchment changes between microsystems ranged from no alteration (rating 0; mostly micro-outlets) to extreme modification (rating 5; mostly micro-estuaries). Two hundred and sixty-seven MPB taxa were identified within all the microsystems, with 247 and 230 MPB taxa being observed in the micro-estuaries and micro-outlets, respectively. The MPB communities differed slightly in terms of microsystem types and seasons, but no significant differences were observed. Multivariate analyses (i.e. Boosted Regression Trees, Canonical Correspondence Analysis) showed that water column variables were significant and important in structuring MPB communities, with soluble reactive phosphorus, sediment pH, turbidity, ammonium and temperature being documented as key drivers. The MPB community composition clearly reflected the influence of catchment anthropogenic activities on species composition and structure. Moderately modified catchments resulted in MPB community structure variation among water bodies in relationship to land use and salinity gradients. The study found that; (i) by virtue of their size, microsystems and their catchments are likely to be particularly vulnerable to anthropogenic pressures when compared to systems of larger size; (ii) a typical impacted state may reflect reduced environmental heterogeneity which, compared to larger systems, may be achieved over much shorter time periods (following a particular event) or under much less intensive impacts; and (iii) the response in terms of MPB structure may predictably reflect a concomitant change from a complex community dynamic (structure and spatio-temporal attributes) to one that approaches a homogeneous structure (poor spatial zonation, strong taxonomic dominance, low species diversity).