Risk Assessment Of Human Exposure Research Articles

Characteristics and risk assessments of mercury pollution in a county region undergoing industrialization in northeastern China: a case study in Gongzhuling

Mercury pollution in emerging industrial zones and surrounding areas, especially in industrial concentration areas, has attracted much attention. So as to clarify the characteristics of Hg in the environment in China’s small and medium-sized industrial emerging and surrounding areas, central urban area of Gongzhuling, a traditional agricultural town with a high degree of industrialization in northeast Changchun industrial base, is taken as the scope. Geological accumulation trin (Igeo) was used to study the degree of soil mercury contamination in Gongzhuling area, latent Er (ecological risk) trin was used to appraise the Er of soil Hg in the study area, and non-carcinogenic risk assessment of mercury in soil using human exposure risk assessment model. The results showed that 34% of soil samples had higher Hg content than the background value of the province’s soil (0.04 mg kg−1). The Igeo results showed that Hg pollution rate of soil in study area was 9% (index >0). In conclusion, the level of soil Hg pollution in Gongzhuling area was low, and the pollution area is mainly concentrated in the northwestern part of the study range. The highest and lowest Er values of soil Hg from the study sample were 2.23 and 214.83, and 24% of the samples had Er > 40, that means they pose a moderate or higher potential ecological risk, and most of these points are located in the northeast of the study range. The main route of human exposure to Hg is oral ingestion. The HQ (non-carcinogenic risk index) and HI (total non-carcinogenic risk value) of soil mercury were both much less than 1, it indicates that the present level of soil Hg in the study range does not pose a threat to local adult health for the time being. This study provides reference for other urban pollution risk assessment, and further defines the direction of future work.

Occurrence and human exposure risk of antibiotic resistance genes in tillage soils of dryland regions: A case study of northern Ningxia Plain, China

Agricultural soils are important source and sink of antibiotic resistance genes (ARGs). However, little is known about the fate of ARGs in dryland soils, while its human exposure risks were seriously overlooked. Taking the northern Ningxia Plain as a case, this study explored the occurrence of ARGs and its relationship with mobile genetic elements (MGEs), pathogens, and environmental factors. Furthermore, the concentrations of airborne ARGs by soil wind erosion and the human exposure doses of soil ARGs were evaluated. The results showed the abundances of different regions ranged from 4.0 × 105 to 1.6 × 106 copies/g. Soil ARGs are driven by MGEs, but multiply impacted by soil properties, nutrition, and bacterial community. Vibrio metschnikovii, Acinetobacter schindleri, and Serratia marcescens are potential pathogenic hosts for ARGs. Further exploration revealed the concentration of ARGs loaded in dust by soil wind erosion reached more than 105 copies/m3, which were even higher than those found in sewage treatment plants and hospitals. Skin contact is the primary route of ARGs exposure, with a maximum dose of 24071.33 copies/kg/d, which is largely attributed to ARGs loaded in dust. This study bridged the gap on ARGs in dryland soils, and provided reference for human exposure risk assessment of soil ARGs.

Polystyrene nanoplastics accelerate atherosclerosis: Unraveling the impact on smooth muscle cells through KIF15-mediated migration

Microplastics and nanoplastics (MNPs) originating from plastic pollution pose potential threats to cardiovascular health, with prior studies linking MNPs to atherosclerosis. Our earlier research elucidated how nanoplastics enhance macrophages' phagocytic activity, leading to the formation of foam cells and an elevated risk of atherosclerosis. However, the specific influence of MNPs on smooth muscle cells (SMCs) in the context of MNP-induced atherosclerosis remains poorly understood. In this study, ApoE knockout (ApoE-/-) male mice with a high-fat diet were orally exposed to environmentally realistic concentrations of 2.5–250 mg/kg polystyrene nanoplastics (PS-NPs, 50 nm) for consecutive 19 weeks. Cardiovascular toxicity was comprehensively assessed through histopathological, transcriptomic, and proteomic analyses, while mechanisms underlying this toxicity were explored through in vitro studies. Herein, hematoxylin and eosin staining revealed accelerated atherosclerotic plaque development in ApoE-/- mice exposed to PS-NPs. Multi-omics analysis identified kinesin family member 15 (KIF15) as a pivotal target molecule. Both in vitro and in vivo experiments affirmed the specific upregulation of KIF15 in mouse aortic SMCs exposed to PS-NPs. Furthermore, in vitro experiments demonstrated that PS-NPs can promote the migration ability of MOVAS cells. Knockdown of Kif15 revealed its role in reducing MOVAS cell migration, with subsequent exposure to PS-NPs reversing the increased migration ability. This suggests that PS-NPs promote SMC migration by upregulating KIF15, and the migration of SMCs is closely associated with atherosclerosis outcomes. This study significantly advances our understanding of MNP-induced cardiovascular toxicity, providing valuable insights for risk assessment of human MNP exposure.

Bioaccumulation of legacy and emerging per- and polyfluoroalkyl substances in hydroponic lettuce and risk assessment for human exposure

Reclaimed water for irrigation or hydroponic cultivation provides exposure pathways for per- and polyfluoroalkyl substances (PFAS) to enter the human food chain. This study employed hydroponic methods to investigate the behavior of legacy PFAS and emerging chlorinated polyfluoroalkyl ether sulfonic acids (Cl-PFESAs) in lettuce grown under environment-related exposure levels and assessed the human exposure risks from consuming contaminated lettuce. Overall, PFAS in lettuce were concentration-dependent, with long-chain PFAS tending to accumulate in roots and short-chain PFAS accumulating more in shoots. The enrichment of PFAS in lettuce was jointly influenced by their chain length and polar functional groups. Specifically, the root concentration factors (RCFs) of PFAS generally increased with increasing chain length, and RCF values of most perfluoroalkanesulfonic acids (PFSAs) were significantly higher than those of perfluoroalkyl carboxylic acids (PFCAs) with the same chain length (p < 0.01), while the translocation factors (TFs) exhibited opposite trends. RCF values of perfluorooctane sulfonate (PFOS) and its alternatives, Cl-PFESAs, were ranked as follows: 8:2 Cl-PFESA (mean: 139) > 6:2 Cl-PFESA (28.6) > PFOS (25.7), which was attributed to the increased molecular size and hydrophobicity resulting from the insertion of ether bonds and additional CF2 in 8:2 Cl-PFESA. Notably, TF value of 8:2 Cl-PFESA (mean: 0.007) was the smallest among all PFAS, indicating 8:2 Cl-PFESA was difficult to transfer to nutritional compartments. Adults and children would exceed the most conservative health-based reference dose (RfD) by consuming approximately 15.9–148 g and 7.92–74.0 g of contaminated lettuce per day, implying high health risks.

The level, human exposure, and health risk assessment of acrylamide in chips and breakfast cereals: A study from Türkiye

The aim of this study is to determine the acrylamide levels of corn chips, potato chips and breakfast cereals and to evaluate the acrylamide exposure level resulting from the consumption of these foods in terms of health risks. Firstly, the acrylamide levels of corn chips (n=19), potato chips (n=11), and breakfast cereals (n=20) were determined by liquid chromatography-tandem mass spectrometry. Then, the dietary acrylamide exposure resulting from chips and breakfast cereals consumption was calculated. Finally, dietary acrylamide exposure, target hazard quotient, the lifetime carcinogenic risk, and the margin of exposure approach values were calculated. The mean acrylamide levels of corn chips, potato chips, and breakfast cereals were 317±12, 3578±546, and 138±14 µg/kg, respectively. The mean acrylamide level of all chips was 1513±1876 µg/kg. The mean daily acrylamide exposure from the consumption of corn chips, potato chips, and breakfast cereals was calculated as 0.11±0.10, 1.28±0.58, and 0.08±0.06 µg/kg bw/day, respectively. The target hazard quotient values of acrylamide exposure from the consumption of corn chips, potato chips (except ketchup-flavored potato chips), and breakfast cereals are less than 1. However, the level of acrylamide exposure from the consumption of a total of 13 food samples−2 from corn chips, 10 from potato chips, and 1 from breakfast cereals−reaches alarming levels in terms of carcinogenic health risks. It is required that consumers reduce the frequency and amount of consumption of chips and breakfast cereals, especially potato chips. The results can serve as a guide for reducing exposure to acrylamide through chips and breakfast cereals consumption.

Detection of Ochratoxin A and Human Exposure Risk Assessment in Rasa roxburghii by SPE-UHPLC-MS/MS

Detection of Ochratoxin A and Human Exposure Risk Assessment in <em>Rasa roxburghii</em> by SPE-UHPLC-MS/MS

Per- and polyfluoroalkyl substances in Chinese commercially available red swamp crayfish (Procambarus clarkii): Implications for human exposure and health risk assessment

The extensive utilization of per- and polyfluoroalkyl substances (PFASs) has led to their pervasive presence in the environment, resulting in contamination of aquatic products. Prolonged exposure to PFASs has been linked to direct hepatic and renal damage, along with the induction of oxidative stress, contributing to a spectrum of chronic ailments. Despite the recent surge in popularity of red swamp crayfish as a culinary delicacy in China, studies addressing PFASs' exposure and associated health risks from their consumption remain scarce. To address this gap, our study investigated the PFASs’ content in 85 paired edible tissue samples sourced from the five primary red swamp crayfish breeding provinces in China. The health risks associated with dietary exposure were also assessed. Our findings revealed widespread detection of PFASs in crayfish samples, with short-chain perfluoroalkyl carboxylic acids (PFCAs) exhibiting the highest concentrations. Notably, the total PFAS concentration in the hepatopancreas (median: 160 ng/g) significantly exceeded that in muscle tissue (5.95 ng/g), as did the concentration of every single substance. The hazard quotient of perfluorohexanesulfonic acid (PFHxS) via consuming crayfish during peak season exceeded 1. In this case, a potential total non-cancer health risk of PFASs, which is mainly from the hepatopancreas and associated with PFHxS, is also observed (hazard index>1). Thus, it is recommended to avoid consuming the hepatopancreas of red swamp crayfish. Greater attention should be paid to governance technology innovation and regulatory measure strengthening for short-chain PFASs.

Restricted-Access Media Column Switching Online Solid-Phase Extraction UHPLC-MS/MS for the Determination of Seven Type B Trichothecenes in Whole-Grain Preprocessed Foods and Human Exposure Risk Assessment.

With increasing health awareness and the accelerating pace of life, whole-grain prepared foods have gained popularity due to their health benefits and convenience. However, the potential risk of type B trichothecene toxins has also increased, and these mycotoxins in such foods are rarely regulated. In this study, a quantitative method combining a single-valve dual-column automatic online solid-phase extraction system with ultra-high-performance liquid chromatography-tandem mass spectrometry (UHPLC-MS/MS) was developed for the first time using restricted-access media columns. This method can simultaneously determine trace residues of seven type B trichothecenes within 15 min. The method is convenient, sensitive (limit of detection and quantification of 0.05-0.6 μg/kg and 0.15-2 μg/kg, respectively), accurate (recovery rates of 90.3%-106.6%, relative standard deviation < 4.3%), and robust (>1000 times). The established method was applied to 160 prepared food samples of eight categories sold in China. At least one toxin was detected in 70% of the samples. Whole-wheat dumpling wrappers had the highest contamination rate (95%) and the highest total content of type B trichothecenes in a single sample (2077.3 μg/kg). Exposure risk assessment indicated that the contamination of whole-grain prepared foods has been underestimated. The total health risk index of whole-wheat dumpling wrappers, which are susceptible to deoxynivalenol, reached 136.41%, posing a significant threat to human health. Effective measures urgently need to be taken to control this risk.

P-Phenylenediamine Derivatives in Tap Water: Implications for Human Exposure

Human exposure to p-phenylenediamine derivatives (PPDs) may induce hepatotoxicity and altered glycolipid metabolism. Recent studies have demonstrated the wide presence of PPDs in environmental matrixes. However, until now, the occurrence of PPDs in tap water has not been well known. This study analyzed nine PPDs in tap water collected from Hangzhou and Taizhou, China. The results showed that seven PPDs were detected in tap water samples from Hangzhou (n = 131), with the concentration of total detected PPDs ranging from 0.29 to 7.9 ng/L (mean: 1.6 ng/L). N-(1, 3-dimethylbutyl)-N′-phenyl-p-phenylenediamine (6PPD; mean: 0.79 ng/L, &lt;LOD−5.7 ng/L) was the predominant PPD in tap water from Hangzhou, followed by N, N′-di-2-butyl-p-phenylenediamine (44PD; 0.39 ng/L, &lt;LOD−2.2 ng/L) and N-isopropyl-N′-phenyl-1, 4-phenylenediamine (IPPD; 0.31 ng/L, &lt;LOD−1.4 ng/L). Five PPDs were detected in tap water collected from Taizhou (n = 30). N-phenyl-N′-cyclohexyl-p-phenylenediamine (CPPD; mean: 1.0 ng/L, &lt;LOD−4.2 ng/L) was the predominant PPD in tap water from Taizhou, followed by 6PPD (0.93 ng/L, &lt;LOD−2.6 ng/L) and 44PD (0.78 ng/L, &lt;LOD−1.8 ng/L). The mean daily intake (DI) of PPDs for adults and children in Hangzhou was estimated to be 4.9–24 and 6.4–32 pg/kg bw/day, respectively. Meanwhile, the mean DI of PPDs for adults and children living in Taizhou was 11–31 and 14–40 pg/kg bw/day, respectively. To our knowledge, this study provides the first data on the occurrence of PPDs in tap water, which is vital for human exposure risk assessment.

Characteristics of microplastics in the atmosphere of Anyang City.

In order to clarify the characteristics of microplastics in the atmosphere of Anyang city, TSP, PM10, and PM2.5 samples are collected when the ambient air quality is good, slightly polluted, and severely polluted. After pretreatment, the physical and chemical characteristics are observed and identified by using stereomicroscope and micro-infrared spectrometer. The results show that the average abundance of microplastics is 0.19 items/m3, 0.26 items/m3, and 0.42 items/m3, respectively, when the ambient air quality is good, light pollution, and heavy pollution in Anyang City. It can be seen that with the decline of ambient air quality, the average abundance of microplastics in TSP, PM2.5, and PM10 gradually increases. The black fiber strip microplastics account for about 80% of the total TSP, PM2.5, and PM10 in the ambient air of Anyang City, followed by yellow flake and black granular microplastics and a small amount of green, red, and blue fiber strip microplastics. AQI has a good correlation with the abundance of microplastics in TSP, PM10, and PM2.5, and the maximum microplastic trapping effect could be obtained according to the sampling method of PM2.5 in the ambient air. The main components of microplastics are cellophane, followed by PET and EVA. The explorations of human respiratory exposure risk assessment show that with the increase of AQI, the daily intake of microplastics in adults also increased. At high levels of pollution, the human body breathes an average of 222 ± 5 microplastics per day.

Presence of carbazole and polyhalogenated carbazoles in human urine

Exposure to carbazole (CZ) and polyhalogenated carbazoles (PHCZs) may pose a threat to human health, owing to their potential dioxin-like toxicity. Until now, the presence of these chemicals in the human urine from the general population is still unclear. Human urine samples (n = 210) were taken from the general population in Quzhou, China in this study, and were analyzed for CZ and 14 PHCZs. CZ and nine PHCZs were detected in collected human urine. CZ (detection frequency 100 %), 3-chlorocarbazole (3-CCZ; 88 %), 3,6-dichlorocarbzole (36-CCZ; 84 %), and 3-bromocarbazole (3-BCZ; 80 %) were more frequently detected. Among detected PHCZs, 3-CCZ (mean 0.49 ng/mL, < LOD–4.3 ng/mL) had comparatively higher urinary levels, followed by 3-BCZ (0.30 ng/L, < LOD–1.9 ng/mL) and 36-CCZ (0.20 ng/L, < LOD–1.4 ng/mL). Urinary concentrations of CZ in male participants (1.3 ± 0.26 ng/mL) were significantly (p < 0.05) higher than that in female participants (0.92 ± 0.24 ng/mL). No obvious trend in urinary concentrations with the age of participants was found for CZ and detected PHCZs. The mean daily excretion was found highest for CZ (31 ng/kg bw/day), followed by 3-CCZ (19 ng/kg bw/day) and 3-BCZ (8.5 ng/kg bw/day). This study provides the first data, to our knowledge, on the presence and levels of CZ and PHCZs in human urine, which is necessary for conducting the human exposure risk assessment.

Combined exposure of nano-titanium dioxide and polystyrene nanoplastics exacerbate oxidative stress-induced liver injury in mice by regulating the Keap-1/Nrf2/ARE pathway.

It is well known that polystyrene nanoplastics (PS-NaP) and nano-titanium dioxide (TiO2 NPs) are frequently co-appeared in daily life and can cause liver injury when they accumulate in the liver. Nonetheless, the combined toxicological impacts and potential molecular mechanisms of PS-NaP and TiO2 NPs in the hepatic system have not been revealed. Thus, we conducted experiments on C57BL/6 mice exposed to PS-NaP or/and TiO2 NPs for 4 weeks. The findings suggested that PS-NaP and TiO2 NPs co-exposed significantly altered the hepatic function parameters, levels of antioxidant-related enzymes and genes expression of Keap-1/Nrf2/ARE signaling pathway, as well as significantly increased the hepatic Ti contents, aggravated hepatic pathological and oxidative stress (OS) damage compared with individual exposure to PS-NaP or TiO2 NPs. Using N-Acetyl-L-cysteine (NAC), an OS inhibitor, we further demonstrated that OS played a pivotal role in coexposure-induced liver injury. NAC reduced the levels of OS in mice, which mitigated co-exposure-induced liver injury. Taken together, we proposed that PS-NaP and TiO2 NPs co-exposed activated the Keap-1, then inhibited the recognition of Nrf2 and ARE, consequently exacerbated liver injury. These findings shed light on the co-toxicity and potential mechanism of nanoplastics and nanoparticles, which informed the risk assessment of human exposure to environmental pollutants.

Health risk assessment for human mercury exposure from Cinnabaris-containing Baizi Yangxin Pills in healthy volunteers Po administration

BackgroundCinnabaris (α-HgS), a mineral traditional Chinese material medica, has been used in combination with other herbs manifesting some definite therapeutic effects for thousands of years. But the currently reported mercury poisoning incidents raised the doubts about the safety of Cinnabaris-containing traditional Chinese medicines (TCMs). Baizi Yangxin Pills (BZYXP) is a Cinnabaris-containing TCM widely used in clinical practice. This study evaluated the health risk of mercury exposure from BZYXP in healthy volunteers based on the total mercury and mercury species analysis of blood and urine after single and multiple doses of BZYXP. MethodsBlood pharmacokinetics and urinary excretion studies of mercury were compared between single (9 g, once daily) and multiple doses (9 g, twice daily, continued for 7 days) of BZYXP. The whole blood and urine samples were collected at the specific points or periods after the administration of BZYXP. The total mercury and mercury species in blood and urine samples were determined by cold vapor-atomic fluorescence spectrometry (CV-AFS) and HPLC-CV-AFS, respectively. ResultsThe mercury was excreted slowly and accumulated obviously after continuous exposure of BZYXP. Moreover, the well-known neurotoxin methylmercury (MeHg) was detected in blood samples after 7 days’ administration of BZYXP. In the urine samples, only Hg(II) was detected. Therefore, long-term use of BZYXP will cause mercury poisoning due to mercury's high accumulative properties and MeHg formation. ConclusionCinnabaris-containing TCMs such as BZYXP should be restricted to cases in which alternatives are available, and the blood mercury species profile should be monitored during the long-term clinical medication.

Environmental bisphenol A disrupts methylation of steroidogenic genes in the ovary of Paradise threadfin Polynemus paradiseus via abnormal DNA methylation: Implications for human exposure and health risk assessment

Bisphenol A, endocrine-disrupting chemicals (EDCs) impacting disease development via epigenetic modifications, is crucial in transcriptional regulation. However, ecotoxicology's limited exploration of epigenetics prompted our study's objective: examining the extended exposure of riverine Bisphenol A (BPA), a potent EDC, on DNA methylation during female paradise threadfin (Polynemus paradiseus) reproductive maturation. Assessing BPA contamination in riverine water, we collected fish samples from two locations with distinct contamination levels. In the highly contaminated region (Hc), we observed elevated DNA methylation in aromatase (7.5-fold), 20β-HSD (3-fold), and FSHR (2-fold) genes. Hormone receptor investigation highlighted an escalating connection between transcriptional hyper-methylation and contamination levels. Additionally, our study revealed a positive correlation between oocyte growth and global DNA methylation, suggesting BPA's potential to modify DNA methylation in female paradise threadfins. This effect likely occurs through changes in hormone receptor expression, persisting throughout oocyte maturation. Notably, our research, the first of its kind in estuarine areas, confirmed BPA contamination in paradise threadfins, raising concerns about potential health risks for humans.

Biomonitoring and risk assessment of human exposure to triazole fungicides

Risk assessment and biomarkers were evaluated in volunteers exposed to triazole fungicides in southern Minas Gerais, Brazil. Volunteers were divided into two groups: occupationally and environmentally exposed to pesticides (n = 140) and those unexposed (n = 50) from urban areas. Urine samples were analyzed by GC-MS for triazoles, and samples from men and women in the exposed group were quantified. Groups were further stratified by sex to evaluate the biomarkers results. Oxidative stress was indicated by biomarker analysis for occupationally exposed men with elevated malondialdehyde levels and reduced superoxide dismutase and catalase activity (p < 0.0001). Bile acid levels were also elevated in the exposed group (p < 0.0001). Biomarkers in this study suggest recent, reversible changes due to pesticide exposure. Liver enzyme levels showed no significant differences. The highest Estimated Daily Intake for epoxiconazole ranged from 0.534 to 6.31 μg/kg-bw/day for men and 0.657–8.77 μg/kg-bw/day for women in the exposed group. Considering the highest detected urinary triazole value, the calculated Hazard Quotient for epoxiconazole was 0.789 for men and 1.1 for women. Results indicate a health risk associated with environmental triazole exposure, highlighting the importance of biomonitoring in risk assessment to prevent intoxication and assist in mitigating adverse health effects from chronic pesticide exposure.

Multiple pesticide residues and risk assessment of Dendrobium officinale Kimura et Migo: a three-year investigation.

Dendrobium officinale Kimura et Migo (D. officinale) is a traditional Chinese medicine homologous to food, and its safety has attracted considerable attention. Pesticide residues are critical indicators for evaluating the safety of D. officinale. This study investigated the levels of 130 pesticides in 137 stem samples and 82 leaf samples from five main production areas of D. officinale in Zhejiang Province, along with the associated risk of dietary exposure for the population between 2019 and 2021. Forty-five pesticides were detected in 171 samples, of which pyraclostrobin had the highest detection frequency. Multiple residues were detected in 52.56% of the stem samples and 54.88% of the leaf samples, and one stem sample contained up to 18 pesticides. Here, the level of difenoconazole in three samples (two stem samples and one leaf sample) was higher than the maximum residue limit (MRL) in China. Considering the possible health risks related to pesticide residues, a risk assessment of human exposure to pesticides via the intake of D. officinale stems and leaves was evaluated, indicating negligible short-term, long-term, and cumulative risks to human health. However, considering the high detection rate of unregistered pesticides, the supplementation of pesticide registration information on D. officinale should be expedited, and MRLs should be established to ensure food and drug safety.

Occurrence and human exposure risk assessment of brominated and organophosphate flame retardants in indoor dust in Ha Noi, Viet Nam

Occurrence and human exposure risk assessment of brominated and organophosphate flame retardants in indoor dust in Ha Noi, Viet Nam

Human exposure risk assessment for infectious diseases due to temperature and air pollution: an overview of reviews.

Air pollution and global temperature change are expected to affect infectious diseases. Air pollution usually causes inflammatory response and disrupts immune defense system, while temperature mainly exacerbates the effect of vectors on humans. Yet to date overview of systematic reviews assessing the exposure risk of air pollutants and temperature on infectious diseases is unavailable. This article aims to fill this research gap. PubMed, Embase, the Cochrane Library, Web of Science, and the Cumulative Index to Nursing and Allied Health Literature were searched. Systematic reviews and meta-analyses investigated the exposure risk of pollutants or temperature on infectious diseases were included. Two investigators screened literature, extracted data and performed the risk of bias assessments independently. A total of 23 articles met the inclusion criteria, which 3 (13%) were "low" quality and 20 (87%) were "critically low" quality. COVID-19 morbidity was associated with long-term exposure PM2.5 (RR = 1.056 per 1 [Formula: see text], 95% CI: 1.039-1.072) and NO2 (RR = 1.042 per 1 [Formula: see text], 95% CI: 1.017-1.068). In addition, for each 1°C increase in temperature, the morbidity risk of dengue increased 13% (RR = 1.130 per 1°C, 95% CI: 1.120-1.150), infectious diarrhea increased 8% (RR = 1.080 per 1°C, 95% CI: 1.050-1.200), and hand, foot and mouth disease (HFMD) increased 5% (RR = 1.050 per 1°C, 95% CI: 1.020-1.080). In conclusion, PM2.5 and NO2 increased the risk of COVID-19 and temperatures were associated with dengue, infectious diarrhoea and HFMD morbidity. Moreover, the exposure risk of temperature on COVID-19 was recommended to be further explored.

Distribution, Respiratory Exposure, and Traceability of Atmospheric Microplastics in Yichang City

As an emerging environmental pollutant, microplastics have attracted much attention, but the sources and health hazards of atmospheric microplastics (AMPs) remain unclear. In order to explore the distribution characteristics, assess the risk of human respiratory exposure, and analyze the sources of AMPs in different functional areas of Yichang City, AMPs samples from 16 observation points were collected and analyzed, and the HYSPLIT model was used. The results showed that the main shapes of AMPs in Yichang City were fiber, fragment, and film, and six colors were observed including transparent, red, black, green, yellow, and purple. The smallest size was 10.42 μm, and the largest was 4761.42 μm. The deposition flux of AMPs was (4400±474) n·(m2·d)-1. The types of APMs were polyester fiber (PET), acrylonitrile-butadiene-styrene copolymer (ABS), polyamide (PA), rubber (Rubber), polyethylene (PE), cellulose acetate (CA), and polyacrylonitrile (PAN). The order of the subsidence flux in each functional area was as follows:urban residential area>agricultural production area>landfill>chemical industrial park>town residential area. The human respiratory exposure risk assessment models showed that the daily intake of AMPs (EDI) for adults and children in urban residential areas was higher than in town residential areas. The atmospheric backward trajectory simulation showed that the AMPs in the districts and counties of Yichang City mainly came from the surrounding areas via short-distance transportation. This study provided basic data support for the research on AMPs in the middle reaches of the Yangtze River and was of great significance for the traceability and health risk research of AMPs pollution.

Antimicrobial resistant Escherichia coli prevalence in freshwaters in Belgium and human exposure risk assessment

The objective of this work was to evaluate the antimicrobial resistant (AR) E. coli prevalence in recreational waters in Belgium and to assess the exposure risk for bathers. Nine stations were sampled during the 2021 bathing season. A total of 912 E. coli strains were isolated and tested by the disk diffusion method in accordance with EUCAST recommendations, including Extended-Spectrum Beta-Lactamase (ESBL) production. AR E. coli were counted at each bathing sites, 24% of strains were resistant to at least one antibiotic and 6% were Multi-Drug Resistant (MDR). A Multiple Antibiotic Resistance (MAR) index was calculated to compare the bathing sites. The Lesse river had the highest MAR index as well as the highest E. coli absolute abundance and the largest number of ESBL-producing E. coli. Conversely, the 3 lakes showed lower E. coli contamination levels and AR rates. A human health risk assessment of exposure to AR E. coli, based on the calculation of measured prevalence, was performed considering four different dose-response model scenarios. The human health risk (Pd) ranged from 10−9 to 0.183 (children). The exposure probabilities were low, except for scenario 3 (E. coli O157:H7), which is the most severe.