To assess heavy metal pollution and human health risk, a total of 28 topsoil samples were collected during four seasons from seven agricultural soil sites near a famous smelter in Jiyuan, China. The maximum concentrations of Cd, Pb, Hg, As, Zn, Cu, Ni, and Cr were 26.00, 2601.00, 3.29, 65.00, 410.00, 156.30, 54.80, and 73.60 mg kg⁻¹, respectively. Compared with the sampling site nearest to the smelter, the concentrations of six metals at the farthest site were decreased significantly (P < 0.05). All sites were heavily contaminated, with Nemerow index (P) >3.0, and all sites had very high ecological risks related to Cd and Hg. The non-carcinogenic risk for children (based on combined exposure to the eight metals) was above the safety level. The carcinogenic risk of As for adults (8.98 × 10^–6) and children (1.49 × 10^–5) exceeded the acceptable level (1 × 10^–6). Results suggest a serious health risk in the polluted areas, particularly for children. Abbreviation Cd: Cadmium; Pb: Lead; Hg: Mercury; As: Arsenic; Zn: Zinc; Cu: Copper; Ni: Nickel; Cr: Chromium; P: Nemerow index; RI: Potential ecological risk index; E_i: Monomial potential ecological risk of a specific heavy metal; HI: non-carcinogenic hazard index; CR: Carcinogenic risk; TN: Total nitrogen; TP: Total phosphorus; OM: Organic matter; MC: Moisture content; ADD: Average daily dose

Antibiotics in breeding industry can enter the environment through multiple pathways, thus accelerating the emergence and spread of antibiotic resistance genes (ARGs), among which aerosol transmission is easily achieved and often overlooked. To elucidate the role of aerosols in this situation, the present study investigated the distribution characteristics of 107 ARG subtypes (targeting to eight different ARG types) and nine mobile genetic elements (MGEs) and bacterial community in animal (chicken cloaca), environment (aerosols) and human (nasopharynx) of a chicken farm (n = 42) in Henan Province. In total, 116 ARG subtypes and MGEs were identified in the poultry farm. The total bacterial concentration of aerosols inside the chicken house (3.117 × 10⁴ CFU/m³) exceeded the corresponding limit. The microbial communities in the samples of cloaca swab (C) and the workers' nasopharyngeal swab (N) were closer, while the abundance distribution of ARGs/ MGEs in cloacal swab (C) and aerosol (AI) in chicken house were much similar. There were certain consistency of the microbial community structure and the distribution of ARGs among the three groups of chicken cloaca, air aerosol, and workers' nasopharynx. Our results highlighted that animal breeding does have a certain impact on the surrounding environment and human, and aerosols play an important role in this process.

The increase in the antimicrobial resistance (AMR) of Staphylococcus aureus (S. aureus) has become a global public health concern. This study globally monitored the large-scale longitudinal trend of AMR in S. aureus and examined the various human and environmental climate factors that influence the occurrence and spread of AMR in S. aureus, which might provide valuable data to support the development of a global surveillance system for S. aureus AMR and provide a theoretical basis for coordinated actions to control the emergence and development of AMR from multiple perspectives. There was a significantly positive correlation between the number of antibiotic resistance genes (ARGs) in S. aureus and the collection year, with a sharp increase in ARGs over time. The number of ARGs in S. aureus genomes significantly increased each decade, with the average number of ARGs per genome rising from 10.37 ± 3.55 before 1990 to 12.75 ± 4.04 after 2010, suggesting a growing problem of S. aureus AMR. The Spearman correlation results indicated that the human development index (HDI), antibiotic consumption, and mobile genetic elements (MGEs) were significantly associated with the AMR of S. aureus, and these factors played a crucial role in the emergence and development of S. aureus AMR. The results of structural equation modeling showed that the HDI significantly promoted an increase in antibiotic consumption, thereby indirectly enhancing the AMR of S. aureus. Antibiotic consumption also indirectly facilitated the progression of AMR in S. aureus through its impact on MGEs. The results of restricted cubic spline and generalized linear models showed that climate change also played a significant role in the progression of S. aureus AMR. In summary, this study provides a theoretical framework for monitoring the longitudinal trend of ARGs in S. aureus isolates and examining the possible influencing variables of ARGs in these isolates.

The nasopharynx is a key niche of the upper respiratory tract which contains many commensal bacteria and potential pathogens. Dysbiosis of the nasopharyngeal (NP) microbiota is associated with a variety of respiratory diseases. Little is known about NP flora in healthy youth, nor about its relationship with environmental factors. We characterized NP microbiota using the 16S rRNA gene sequencing method, and compared microbial composition from subjects sampled in Spring and Fall when exposed to different environmental factors. Results showed that beta diversity was significantly different. Phyla Acidobacteria, Gemmatimonadetes, and genus Symbiobacterium were positively associated with PM_2.5. Genera Streptococcus, Prevotella, and [Prevotella] were positively correlated with temperature (T). Ozone (O₃) was associated with these floras for exposure that occurred 30 days prior to collection. These preliminary data suggest that the change in environmental factors between spring and fall can influence the composition of the NP microbiota, characterized by a significant correlation to specific taxa. These changes in NP microbiota might be a potential risk factor for respiratory disease.