Perfluoroalkyl acids (PFAAs) are widely present in human blood, and have many toxic effects on humans. However, effects of PFAA exposure on the risk of rheumatic immune diseases are limited. In the present study, occurrence of 7 PFAAs, including perfluorooctane sulfonate (PFOS), perfluorooctanoic acid (PFOA), perfluorononanoate (PFNA), perfluorodecanoate (PFDA), perfluoroundecanoate (PFUnA), perfluorododecanoate (PFDoA), and perfluorotrdecanoate (PFTrA), were measured in serum samples from 156 healthy people (controls) and 156 rheumatoid arthritis (RA) cases living in Hangzhou, China. We also investigated the relationships among cumulative PFAA levels in serum, some immune markers, and the incidence of RA. The results showed that PFOA (6.1 and 11.8 ng/mL) had the highest mean serum concentrations, followed by PFOS (3.2 and 3.4 ng/mL) and PFDA (0.86 and 2.6 ng/mL), in both controls and RA cases. Cumulative exposure to PFOA in the study population were positively correlated with the levels of rheumatoid factors (rₛ = 0.69, p < 0.01) and anti-cyclic citrullinated peptide antibody (rₛ = 0.56, p < 0.05). Moreover, significant associations of PFOA concentrations with odds ratios (OR) of RA (OR = 1.998, confidence interval (CI): 1.623, 2.361, p = 0.01) were found by adjusting for various covariates. The crude and adjusted OR for RA was respective 1.385 (95% CI: 1.270, 1.510, p = 0.04) and 1.381 (95% CI: 0.972, 1.658, p = 0.06) for a unit increase in serum PFOS levels, but the adjusted results were not significant. Overall, this case-control study found that human serum PFOA concentrations were positively correlated with RF and ACPA levels.

The terrain effect on atmospheric environment is poorly understood in particular for the polluted region with underlying complex topography. Therefore, this study targeted the Sichuan Basin (SCB), a deep basin with severe PM₂.₅ pollution enclosed by the eastern Tibetan Plateau (TP), Yunnan-Guizhou Plateaus (YGP) and mountains over Southwest China, and we investigated the terrain effect on seasonal PM₂.₅ distribution and the meteorological mechanism based on the WRF-Chem simulation with stuffing the basin topography. It is characterized that the three-dimensional distribution of topography-induced PM₂.₅ concentrations over the SCB with the seasonal shift of regional PM₂.₅ averages from approximately 30 μg m⁻³ in summer to 90 μg m⁻³ in winter at surface layer and from summertime 10 μg m⁻³ to wintertime 30 μg m⁻³ in the lower free troposphere. Such basin-forced PM₂.₅ changes presented the vertically monotonical declines concentrated within the lower troposphere below 3.6 km in spring, 2.3 km in summer, 2.6 km in autumn and 4.8 km in winter. Impacts of deep basin aggravated PM₂.₅ accumulation within the SCB and transport toward the surrounding plateaus contributing approximately 50–90% to PM₂.₅ levels over the regions of eastern TP and northern YGP. In the SCB, atmospheric thermal structure in the lower troposphere could build a vertical convergence layer between the boundary layer and free troposphere, acting as a lid inhibiting air diffusion, which was regulated by the terrain effects on interactions of westerlies and Asian monsoons, especially the wintertime strong warm lid deteriorating air pollution in the SCB. Furthermore, warm and humid air conditions within the basin prompted sulfur oxidation ratio by +0.02 and nitrogen oxidation ratio by +0.22 effectively producing the secondary PM₂.₅ in atmospheric environment.

To investigate the chemical components, sources, and interactions of particulate matter (PM) and volatile organic compounds (VOCs), a field campaign was implemented during the spring of 2018 in nine cities in northwestern (NW) China. PM was mainly contributed by organic matter and water-soluble inorganic ions (41% for PM₁₀ and approximately 60% for PM₂.₅ and PM₁). Two typical haze patterns were observed: anthropogenic pollution type (AP-type), wherein contributions of sulfate, nitrate, and ammonium (SNA) increased, and dust pollution type (DP-type), wherein contributions of Ca²⁺ increased and SNA decreased. Source appointment suggested that regional sources contributed close to half to PM₂.₅ pollution (40% for AP-type and 50% for DP-type). Thus, sources from regional transport are also important for haze and dust pollution. The ranking of VOC concentrations was methanol > acetaldehyde > formic acid + ethanol > acetone. Compared with other cities, there are higher oxygenated VOCs (OVOCs) and lower aromatics in NW China. The relationships between VOCs and PM were discussed. The dominating secondary organic aerosols (SOA) formation potential precursors were C₁₀–aromatics, xylene, and styrene under low–nitrogen oxide (NOx) conditions, and benzene, C₁₀–aromatics, and toluene dominated under high–NOx conditions. The quadratic polynomial was the most suitable fitting model for their correlation, and the results suggested that VOC oxidations explained 6.1–10.8% and 9.9–20.7% of SOA formation under high–NOx and low–NOx conditions, respectively.

We apply a tracer model linked with a 3D circulation model to simulate transport and fate of water-soluble persistent substances in the Black Sea that do not bioaccumulate to a considerable extent. The model uses specified degradation time and identical concentrations in the rivers to build a correlation between average concentration in the basin and half-life (DT50). The average concentration in certain sub-regions of the Black Sea can be estimated using an exponential dependence of DT50, if DT50 and concentration in rivers are known. Averaging is performed on the simulations from 2000 to 2019 with real atmospheric forcing and river runoff. A well-defined seasonal cycle is evident for the average shelf concentration, while the average concentration in the deep region does not show a pronounced seasonal cycle or inter-annual variations. With the help of the existing observational data, we estimate DT50 and concentration in the rivers for carbamazepine, sulfamethoxazole and terbuthylazine. Atrazine and simazine are believed to have accumulated in the basin for a long time due to their widespread use in the past and the slow rate of degradation in the marine environment.

Biosolids containing per- and polyfluoroalkyl substances (PFAS) could contaminate the receiving environments once they are land applied. In this study, we evaluated the feasibility of controlling the bioavailability of PFAS in biosolids to timothy-grass through stabilization or mobilization approaches. Stabilization was accomplished by adding a sorbent (i.e. granular activated carbon (GAC), RemBind, biochar) to biosolids, while mobilization was achieved by adding a surfactant, sodium dodecyl sulphate (SDS), to biosolids. The results showed that the ΣPFAS concentration in grass shoots grown in biosolids amended soil treated by GAC or RemBind at 2% was only 2.77% and 3.35% of the ΣPFAS concentration detected in shoots grown in biosolids amended soil without a sorbent, respectively, indicating the effectiveness of GAC and RemBind for stabilizing PFAS and reduce their bioavailability. On the other hand, mobilization by adding SDS to biosolids at a dose range of 10–100 mg/kg significantly increased the plant uptake of ΣPFAS by 15.48%–108.57%. Thus, mobilization by adding SDS could be a valuable approach for enhancing the PFAS removal if phytoremediation is applied. Moreover, higher rate of PFAS uptake took place after grass cutting was observed in this study. Thus, proper mowing and regrowth of timothy-grass could lead to efficient and cost-effective removal of PFAS from biosolids amended soil through phytoremediation and leave the site clean to be used for other purposes.

Polyhalogenated polycyclic aromatic hydrocarbons (HPAHs) represent a major environmental concern due to their persistency and toxicity. Among them, mono-halogenated (HNs) and halomethyl naphthalenes (HMNs) are not well-studied, and the toxicity of many HNs to fishes has not been reported. In this study, we exposed zebrafish (Danio rerio) embryos to naphthalene and five HNs at concentrations ranging from 0.25 to 2.0 mg L⁻¹ to assess acute toxicities and developmental effects. Among them, 2-bromomethyl naphthalene (2-BMN) produced moderate lethal effects (96-h LC₅₀ = 1.4 mg L⁻¹) and significantly reduced hatchability. Abnormal phenotypes, including pericardial edema, spine curvature, and shortened body length, were also induced by 2-BMN (96-h EC₅₀ = 0.45 mg L⁻¹). Treatments of 0.5–2.0 mg L⁻¹ 2-BMN evoked cardiac malformations via significant down-regulation of the cacna1c gene, which codes the voltage-dependent calcium channel, at 72 hpf and up-regulation of the nppa gene, responsible for the expression of natriuretic peptides, at 96 hpf in zebrafish. One presumable toxic photo-dissociated metabolite of 2-BMN, the 2-naphthylmethyl radical, may be responsible for the toxic effect on zebrafish embryos. HPAHs must be monitored and managed due to their adverse effects on living organisms at low concentrations.

In China, PM₂.₅ pollution has caused extensive death and economic loss. Thus, an accurate assessment of the spatial distribution of these losses is crucial for delineating priority areas for air pollution control in China. In this study, we assessed the PM₂.₅ exposure-related health effects according to the integrated exposure risk function and non-linear power law (NLP) function in 338 prefecture-level cities in China by utilizing online monitoring data and the PM₂.₅ Hindcast Database (PHD). Our results revealed no significant difference between the monitoring data and PHD (p value = 0.66 > 0.05). The number of deaths caused by PM₂.₅-related Stroke (cerebrovascular disease), ischemic heart disease, chronic obstructive pulmonary disease, and lung cancer at the national level estimated through the NLP function was 0.27 million (95% CI: 0.06–0.50), 0.23 million (95% CI: 0.08–0.38), 0.31 million (95% CI: 0.04–0.57), and 0.31 million (95% CI: 0.16–0.40), respectively. The total economic cost at the national level in 2016 was approximately US$80.25 billion (95% CI: 24.46–132.25). Based on a comparison of Z statistics, we propose that the evaluation results obtained using the NLP function and monitoring data are accurate. Additionally, according to scenario simulations, Beijing, Chongqing, Tianjin, and other cities should be priority areas for PM₂.₅ pollution control to achieve considerable health benefits. Our statistics can help improve the accuracy of PM₂.₅-related health effect assessments in China.

Lichens play an important role in the biogeochemical cycling of mercury (Hg) and are commonly used as indicators of Hg enrichment in remote and anthropogenically impacted environments. To assess their capacity for Hg uptake and accumulation, we determined the concentration of gaseous elemental mercury (GEM) in air and the concentration of total Hg (THg) in transplanted thalli of two lichen species. Lichen transplants and passive air samplers (PASs) were concurrently deployed, side by side, at 10 sites within an abandoned mining area, characterized by large gradients in atmospheric Hg contamination. Highly variable time-weighted GEM concentrations determined by the PASs, ranging from 17 to 4,200 ng/m³, were mirrored by generally high Hg concentrations in transplanted thalli of both Xanthoria parietina (174–8,800 ng/g) and Evernia prunastri (143–5,500 ng/g). Hg concentrations in the two species co-varied linearly indicating about 60% greater Hg accumulation in X. parietina than in E. prunastri. Whereas Hg uptake in the fruticose E. prunastri increased linearly with GEM, a power law equation with a fractional exponent described the uptake in the foliose X. parietina. Extrapolating the relationships observed here to higher GEM levels yielded concentrations in lichen that agree very well with those measured in an earlier fumigation experiment performed under laboratory-controlled conditions. The uptake model of X. parietina was further verified by correctly estimating GEM concentrations from the THg measured in autochthonous thalli collected from the urban area adjacent to the mine site. Passive sampling can effectively provide time-weighted data of suitable spatial resolution to quantitatively describe GEM assimilation by lichens. Therefore, the combined use of passive sampling and lichen transplants can contribute to a more comprehensive understanding of the role of lichens, and potentially also of other cryptogams, in the deposition of atmospheric Hg to terrestrial ecosystems.

The attachment and colonization process of microorganisms on a carrier is an interdisciplinary research field. Through a series of physical, chemical, and biological actions, the microorganisms can eventually reproduce on the carrier. This article introduces biofilm start-up and its applications, and explores the current issues to look forward to future development directions. Firstly, the mechanism of microbial film formation is analyzed from the microbial community colonization and reproduction process. Secondly, when analyzing the factors influencing microbial membrane formation, the effect of microbial properties (e.g., genes, proteins, lipids) and external conditions (i.e., carrier, operating environment, and regulation mechanism among microbial communities) were discussed in depth. Aimed at exploring the mechanisms and influencing factors of biofilm start-up, this article proposes the application measures to strengthen this process. Finally, the problems encountered and the future development direction of the technology are analyzed and prospected.