Results about relative changes of N-cycling genes revealed that the variations of N-cycling genes in oil-addition treatments were related to sediment types but not crude oil concentrations, and the genes in HB were more sensitive to crude oil than SY. Network analysis of N-cycling genes found that crude oil decreased the complexity of N-cycling gene networks in SY, while increased complexity in HB, and led to more competition among N-cycling microbes. Our findings help to look into the effects of crude oil on key N-cycling processes, and improve the understanding of the interactions among N-cycling under crude oil contamination. There is solid evidence that haze pollution threatens human health owing to the abiotic pollutants it contains. However, the characteristics of airborne bacterial communities in indoor and outdoor environments exhibiting haze occurrence are still unknown. Thus, we examined variations in both indoor and outdoor airborne bacterial communities in Beijing from December 9-27, 2016, a period which included three haze events. The outdoor airborne bacterial communities were clustered into two main groups (Groups I and II), and they shifted between two typical bacterial communities regardless of the haze event. The Chao1, Shannon, and phylogenetic diversity indexes and abundance of dominant classes changed significantly, as did airborne bacterial community type. The indoor airborne bacterial community closely tracked the outdoor bacterial community type, forming two obvious groups supported by Adonis analysis, changes in dominant classes, and bacterial diversity compared to the outdoor group. Furthermore, we found that the airborne bacterial community type could affect the morbidity of respiratory diseases. Daily pneumonia cases were significantly higher in Group I (p = 0.035), whereas daily amygdalitis cases were significantly higher in Group II (p = 0.025). Interestingly, the enriched classes in the indoor environment were quite different from those in the typical airborne bacterial community environment, except for Clostridia, which had significantly higher abundance in both indoor environments. In conclusion, we found that the two indoor and outdoor airborne bacterial community types changed independently of haze events, and the special airborne bacterial community type was closely related to the incidence of pneumonia in the heavy haze season. Although perfluoroalkyl substances (PFASs) are ubiquitous in the Arctic, their dominant pathways to the Arctic remain unclear. Most modeling studies support major oceanic transport for PFASs in the Arctic seawater, but this conclusion contradicts the rapid response of PFASs to global emissions in some biota species. Sediments, which act as important PFAS sinks for seawater and potential PFAS source to the benthic food web, are important for interpreting the fate of PFASs in the Arctic. Here we investigate the occurrence of 9 PFASs in one core (1945-2014) and 29 surface sediments from the Bering Sea to the western Arctic. Total PFAS concentrations (0.06-1.73 ng/g dw) in surface sediments were dominated by perfluorooctane sulfonate (PFOS), perfluorononanoic acid (PFNA) and perfluorobutyl sulfonate (PFBS), with higher levels in the Bering Sea slope and the northeast Chukchi Sea. Historical trends in PFASs varied among individuals, with PFOS declining in the early 2000s while PFNA showing an increasing up-core trend. Analysis of positive matrix factorization model identified that the major PFAS sources in the sediment core were dominated by the atmospheric oxidation of consumer use of PFOS precursor-based products (45.0%), while the oceanic transport of fluoropolymer manufacture of polyvinylidene fluoride (mainly PFNA) exhibited an increasing trend over time, becoming dominant in surface sediments (42.8%). Besides, local input of possible aqueous fire-fighting foams (mainly PFOS and PFBS) also acted as an important source currently (30.1%) and historically (34.9%). check details Our study revealed that the pathways of PFASs in Arctic sediments varied greatly for individuals and the conclusion of PFOS originating from mainly atmospheric oxidation was different from seawater modeling results. This, together with the high possibility of sediments as direct source to Arctic food web (supported by similar PFAS compositions and temporal variations), help provide additional evidence regarding PFAS pathways to the Arctic. Electronic waste (e-waste) dismantling is an important source of flame retardant emissions, and may have potentially adverse effects on surrounding area. This study investigated their influence on the surrounding area and the human health risks after an industrial park was built in 2015 and environmentally friendly technologies were introduced at an e-waste dismantling site in South China. The concentrations of flame retardants, including polybrominated diphenyl ethers (PBDEs), polybromobenzenes (PBBzs), Dechlorane plus (DP), and organophosphate esters (OPEs), in the soils were measured. The results showed that soil contamination was greater in the industrial park than in the surrounding area. The PBDE concentrations were the highest with BDE209, a daca-BDE, being the dominant congener, followed by OPEs, where triphenyl phosphate levels were the highest. Furthermore, triphenyl phosphate can be used as an indicator of flame retardant emissions during e-waste dismantling in this region. The fanti value of DP was stable at around 0.75. The principal component analysis showed that direct emission was the major source of pollutants in the industrial park. The direct emission proportion decreased in the surrounding area, but migration and transformation increased. None of the chemicals posed a non-carcinogenic risks to children and adults via oral uptake or dermal contact when the absorption factors of the chemicals were included in the estimation. However, the total hazard quotients for children were close to a unit in the industrial park, of which, the PBDE and OPE proportions accounted for 84.2% and 15.8% of the total, respectively. However, the PBBz and DP percentages were negligible. Therefore, PBDEs and OPEs should be given more attention in the future.