The mother-offspring transfer of chlorothalonil through human breast milk: A multi-city cross-sectional study.

4-Hydroxychlorothalonil (4-OH CHT), the main metabolite of chlorothalonil and the most widely used fungicide, has been frequently detected in human samples during monitoring. 4-OH CHT may exhibit higher toxicity and persistence in the environment compared to its prototype. In this study, a total of 540 paired serum and breast milk samples from pregnant women in three provinces in China were monitored for contaminant residues. 4-OH CHT was analyzed in the samples using ultra high-performance liquid chromatography - high-resolution mass spectrometry with a detection limit of 20 ng/L. The study investigated the effects of demographic factors, such as BMI, region of residence, and education level, on the levels of 4-OH CHT residues in serum and breast milk. Among the three provinces, the highest median concentration of 4-OH CHT in serum samples was observed in Hebei (1.04 × 103 ng/L), while the highest median concentration of 4-OH CHT in breast milk samples was observed in Hubei and Guangdong (491 ng/L). Multiple linear regression was used to investigate the significant positive correlation between 4-OH CHT in serum and breast milk (p = 0.000) after adjusting for personal characteristics. Based on this, the study further explored the influencing factors of transfer efficiencies (TEs) in conjunction with the individual TEs and the personal characteristics of the participants. Our results demonstrated that the age of the volunteers and their exercise habits had an effect on TEs, but further studies are needed to determine whether exercise leads to an increase in TEs.

Rediscovery of Lycodongammiei (Blanford, 1878) (Serpentes, Colubridae) in Xizang, China, with comments on its systematic position.

Lycodongammiei (Blanford, 1878), a rarely encountered species of Asian snake, is characterized by ambiguous systematics and biology. Based on a sole specimen of L.gammiei rediscovered in southeastern Xizang, China, we conduct a detailed morphological examination and description, and investigate the systematic position of this species. Morphologically, the newly collected specimen is closely aligned with specimens previously described. Mitochondrial DNA-based phylogenetic analyses reveal that L.gammiei constitutes an independent evolutionary lineage, forming a clade with L.fasciatus (Anderson, 1879), L.gongshan Vogel & Luo, 2011, L.butleri Boulenger, 1900, and L.cavernicolus Grismer, Quah, Anuar, Muin, Wood & Nor, 2014. The closest genetic distance between L.gammiei and its congeners was 10.2%. The discovery of L.gammiei in Medog County, China, signifies an eastward expansion of its known geographical distribution.

Bayesian analysis of physiologically based toxicokinetic (PBTK) modeling for pentachlorophenol exposure in pregnant women.

Pentachlorophenol (PCP) is a persistent organic compound that is widely present in the environment. The estimation of internal exposure levels for a given external exposure using toxicokinetic models is key to the human health risk assessment of PCP. The present study developed a physiologically based multicompartmental pharmacokinetic (PBTK) model to describe and predict the behavior of pentachlorophenol (PCP) in an organism. The model consists of stomach, intestines, adipose tissue, kidneys and fast- and poorly perfused tissues that are interconnected via blood circulation. We constructed a PBTK model of PCP in rats and extrapolated it to human dietary PCP exposure. The toxicokinetic data of PCP in human tissues and excreta were obtained from the published literature. Based on the collected PCP dietary survey and internal exposure data of pregnant women in Shanghai, Bayesian statistical analysis was performed for the model using Markov chain Monte Carlo (MCMC) simulation. The posterior distributions of the sensitive parameters were estimated, and the model was parameter optimized and validated using the pregnant women's test dataset. The results showed that the root mean square error (RMSE) improved 37.3% compared to the original model, and a systematic literature search revealed that the optimized model achieved acceptable prediction results for other datasets in China. A PCP metabolism model based on the exposure characteristics of pregnant women in China was constructed in the present study. The model provides a theoretical basis for the study of PCP toxicity and risk assessment.

Spatial ecology and microhabitat selection of the nocturnal pitviper Viridovipera stejnegeri (Squamata: Viperidae) in relation to prey.

Habitat is fundamental for facilitating various life activities in animals, for instance, snakes procure essential energy for survival and reproduction by selecting ambush microhabitats. While there has been extensive research on the selection of microhabitat for feeding in terrestrial and aquatic snakes, little is known about arboreal snakes. In the present study, we analyzed the ambush microhabitat preferences of Viridovipera stejnegeri, a widely distributed Asian pitviper in China, conducted association analysis between snake microhabitat and prey microhabitat and abundance to determine the ro5le of microhabitat selection in feeding. Employing random forest analysis and habitat selection functions, we further constructed a predictive framework for assessing the probability of ambush site selection by V. stejnegeri. Our results revealed that V. stejnegeri exhibited a distinct microhabitat preference for ambush prey. Among the 13 environmental factors assessed, V. stejnegeri showed pronounced preferences towards 12 of these factors, including climatic factors, geographical factors, and vegetation factors. Furthermore, although the preferences of V. stejnegeri overlapped substantially with those of its prey across multiple habitat factors, food abundance shows no significant association with various habitat factors of V. stejnegeri, and does not have significant predictive effect on habitat selection of V. stejnegeri. Therefore, we infer that V. stejnegeri does not preferentially select microhabitats with the highest food abundance, which does not support the hypothesis that "snakes select habitats based on the spatial distribution of prey abundance." By analyzing the characteristics of vegetation, geography, and climate, we conclude that V. stejnegeri tends to choose microhabitats with better ambush conditions to increase attack success rate, thereby achieving the optimal feeding success rate at the microhabitat scale, which is in line with the predictions of optimal foraging theory. This study provides new insights into the predation ecology and habitat selection of snakes.

Genomic analysis reveals deep population divergence in the water snake Trimerodytes percarinatus (Serpentes, Natricidae).

Although several phylogeographic studies of Asian snakes have been conducted, most have focused on pitvipers, with non-venomous snakes, such as colubrids or natricids, remaining poorly studied. The Chinese keelback water snake (Trimerodytes percarinatus Boulenger) is a widespread, semiaquatic, non-venomous species occurring in China and southeastern Asia. Based on mitochondrial DNA (mtDNA) and single nucleotide polymorphism (SNP) data, we explored the population genetic structure, genetic diversity, and evolutionary history of this species. MtDNA-based phylogenetic analysis showed that T. percarinatus was composed of five highly supported and geographically structured lineages. SNP-based phylogenetic analysis, principal component analysis, and population structure analysis consistently revealed four distinct, geographically non-overlapping lineages, which was different from the mtDNA-based analysis in topology. Estimation of divergence dates and ancestral area of origin suggest that T. percarinatus originated ~12.68 million years ago (95% highest posterior density: 10.36-15.96 Mya) in a region covering southwestern China and Vietnam. Intraspecific divergence may have been triggered by the Qinghai-Xizang Plateau uplift. Population demographics and ecological niche modeling indicated that the effective population size fluctuated during 0.5 Mya and 0.002 Mya. Based on the data collected here, we also comment on the intraspecific taxonomy of T. percarinatus and question the validity of the subspecies T. p. suriki.

Liquid crystal monomers (LCMs) in indoor residential dust from Beijing, China: occurrence and human exposure.

Liquid crystal monomers (LCMs) are widely used in electronic devices and emerging as an environmental pollutant, while their occurrence in indoor environments is still less studied. In this study, 32 out of 37 target LCMs were detected in indoor residential dust samples (n = 112) from Beijing, China. Concentrations of Σ32LCMs ranged from 17.8 to 197 ng/g, with a median value of 54.7 ng/g. Fluorinated biphenyls and analogs (FBAs) and cyanobiphenyls and analogs (CBAs), with median concentrations of 22.8 and 15.9 ng/g, respectively, were the main kinds of LCMs. Although 32 LCMs can be detected, four monomers with the highest contamination levels contributed to almost 70% of the total LCMs. Spearman correlation analysis found significant correlations among some monomers, which indicated that they might share similar sources in the residential environment. Estimated daily intakes (EDIs) of LCMs via indoor dust for Beijing residents were calculated, and the results showed that dust ingestion and dermal contact were both main intake pathways to LCMs, and younger people may face higher exposure to LCMs. A comparison to the results of China's total diet study showed that EDIs of LCMs via food consumption might be higher than that via dust intake, while health risks caused by exposure of LCMs for the general population, both through food and dust, were insignificant at present.

Molecular phylogeny reveals cryptic diversity in Sibynophis from China (Serpentes: Sibynophiidae).

The elucidation of species diversity and distribution is critical within the fields of evolution, genetics, and conservation. The genus Sibynophis contains rare snakes that have historically received little attention. In this study, we conducted comprehensive sampling and use both mitochondrial and nuclear genetic markers to explore Sibynophis species diversity within China. Our findings revealed that S. c. miyiensis should be considered synonymous with S. c. grahami, and S. c. grahami should be gave a specific rank as S. grahami. In addition, we discovered S. triangularis was new to China and Myanmar. Based on the specimens and molecular phylogeny results, we redefined the species distribution boundaries of each Chinese species.

A Nationwide Survey and Risk Assessment of Ethyl Carbamate Exposure Due to Daily Intake of Alcoholic Beverages in the Chinese General Population.

Ethyl carbamate (EC) is carcinogenic, and, in China, oral intake of EC mainly occurs as a result of the consumption of alcoholic beverages. To obtain the latest EC intake and risk analysis results for the general population in China, the China National Center for Food Safety Risk Assessment (CFSA) conducted the sixth total diet study (TDS) as a platform to analyze EC contents and exposure due to the intake of alcoholic beverages. A total of 100 sites in 24 provinces were involved in the collection and preparation of alcohol mixture samples for the sixth TDS. There were 261 different types of alcohol collected across the country, based on local dietary menus and consumption survey results. Ultimately, each province prepared a mixed sample by mixing their respective samples according to the percentage of local consumption. The EC levels of these twenty-four mixed samples were determined using our well-validated gas chromatography-mass spectrometry (GC-MS) method. The values ranged from 1.0 µg/kg to 33.8 µg/kg, with 10.1 µg/kg being the mean. China's EC daily intake ranged from 0.001 ng/kg bw/d to 24.56 ng/kg bw/d, with a mean of 3.23 ng/kg bw/d. According to the margin of exposure (MOE), virtually safe dose (VSD), and T25 risk assessments of the carcinogenicity of EC, the mean lifetime cancer risk for the Chinese population was 9.8 × 104, 1.5 × 10-7, and 8.6 × 10-8, respectively. These data show that the carcinogenicity of EC in the general Chinese population due to alcoholic intake is essentially minimal.

Genomic evidence sheds new light on phylogeny of Rhabdophis nuchalis (sensu lato) complex (Serpentes: Natricidae).

Stable taxonomy and robust phylogeny are essential for the evolution and conservation of organisms. The Rhabdophis nuchalis (sensu lato) complex presently contains three species (R. nuchalis, R. chiwen, R. pentasupralabialis). Although several studies have explored the diversity and phylogeography of this group, certain issues related to systematics and taxonomy remain unresolved. Here, based on genome-wide data, including single nucleotide polymorphisms (SNPs) generated from ddRAD-seq and mitochondrial DNA (mtDNA), we re-evaluated the phylogenetic relationships and cryptic diversity of this species group. Our results are generally consistent with previous studies but provide some new insights. Phylogenetic relationship reconstruction based on SNPs and mtDNA revealed that three species in the R. nuchalis (sensu lato) complex did not form a monophyly but each species is well supported as monophyletic lineage in SNP-based analyses. Population structure analyses showed genetic admixture between several species pairs. Additionally, the population in eastern Yunnan, China, was identified as a potential cryptic species and thus described as a new species based on morphological data. From our results and previous studies, we redefined the distribution boundary for each species in the R. nuchalis (sensu lato) species complex.

Concentrations, Profiles, and Health Risks of Organic Ultraviolet Filters in Eight Food Categories Determined through the Sixth Chinese Total Diet Study.

Ultraviolet (UV) filters are emerging contaminants that have been found in high concentrations in human tissues. Food intake is generally considered to be the primary route of human exposure to contaminants. In this study, 184 composite food samples, prepared from 4268 individual samples in eight categories collected from 23 Chinese provinces for the sixth Chinese total diet study, were analyzed. The total and median UV filter concentrations in food samples were 1.5-68.3 and 7.9 ng/g wet weight, respectively. The highest median concentrations were found in decreasing order in meat, cereals, and legumes. In total, 15 UV filters were analyzed. 2-Ethylhexyl salicylate, homosalate, and 2-ethylhexyl-4-methoxycinnamate were dominant and made median contributions of 34.1%, 22.6%, and 14.5%, respectively, and 2-(2H-benzotriazol-2-yl)-4,6-di-tert-pentylphenol contributed the median of 0.03%, of the total UV filter concentrations. The estimated total daily UV filter intake in animal-origin foods and total UV filter concentration in human milk from the same province were significantly correlated (r = 0.44, p < 0.05). Predicted absorption, distribution, metabolism, and elimination properties led to 10 UV filters being prioritized as most likely to be retained in human tissues. The prioritization results and toxicity assessments indicated that octocrylene and 2-ethylhexyl-4-methoxycinnamate have stronger effects in vivo and therefore require more attention than others.

A Comparison of Clinical Characteristics of Infections with SARS-CoV-2 Omicron Subvariants BF.7.14 and BA.5.2.48 - China, October-December 2022.

What is already known about this topic?: Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) continues to evolve, the clinical manifestations resulting from different SARS-CoV-2 variants may demonstrate significant variation. What is added by this report?: We conducted a comparative analysis of the clinical features associated with SARS-CoV-2 Omicron subvariants BF.7.14 and BA.5.2.48 infections. The results of our study indicate that there are no substantial differences in clinical manifestations, duration of illness, healthcare-seeking behaviors, or treatment between these two subvariants. What are the implications for public health practice?: Timely identification of alterations in the clinical spectrum is crucial for researchers and healthcare practitioners in order to enhance their comprehension of clinical manifestations, as well as the progression of SARS-CoV-2. Furthermore, this information is beneficial for policymakers in the process of revising and implementing appropriate countermeasures.

Monosodium Glutamate Intake and Risk Assessment in China Nationwide, and a Comparative Analysis Worldwide.

The sixth Total Diet Study (TDS) of China included a countrywide study to assess the health effects of MSG (monosodium glutamate). MSG detection, consumption analysis, and risk assessment were conducted on 168 samples from seven food categories of the most typical Chinese daily diet. The highest value of MSG in the daily diet of the Chinese population was 8.63 g/kg. An MSG intake of 17.63 mg/kg bw/d for the general population of China was obtained from content measurements combined with food consumption, while the data from the apparent consumption survey alone gave 40.20 mg/kg bw/d. The apparent consumption did not consider the loss of MSG during food cooking, resulting in an overestimate. To offer a global perspective, MSG content, food category contributions, and ingestion levels across nations were summarized and thoroughly investigated. A realistic, logical, and precise risk assessment protocol for MSG daily intake was developed in this article.

Comprehensive evaluation of perchlorate dietary exposure and health risks for Chinese adult males and breastfed infants.

Perchlorate is an environmental contaminant that has both natural and anthropogenic sources. Widespread contamination of various foods with perchlorate can be caused by water, soil, and fertilizer. Because of concerns about the health effects of perchlorate, attention has focused on its occurrence in food and potential human exposure. In this study, the dietary exposures of Chinese adult males and breastfed infants to perchlorate were evaluated using data from the sixth China Total Diet Study and the third National Breast Milk Monitoring Program conducted between 2016 and 2019. In the sixth China Total Diet Study, perchlorate was detected in 94.8 % of composite dietary samples (n = 288) from 24 provinces in China, while for the third National Breast Milk Monitoring, perchlorate was found in 100 % of pooled breast milk samples (n = 100) collected from 100 cities/counties in China. Vegetables were found to be the main source of dietary exposure for Chinese adult males. Furthermore, the concentrations in breast milk between urban (n = 34, mean: 38.6 µg/L) and rural (n = 66, mean: 59.0 µg/L) regions from 100 cities/counties in China were not significantly different. On average, the estimated daily intake of Chinese adult males (18-45 years) to perchlorate was 0.449 µg/kg bw/day, while that for breastfed infants (0-24 months) was 3.21-5.43 µg/kg bw/day. The exposure to perchlorate in breastfed infants was almost 10-fold greater than that of Chinese adult males.

Genomic Analysis and Antimicrobial Resistance of Campylobacter jejuni Isolated from Diarrheal Patients - Beijing Municipality, China, 2019-2021.

Introduction: Campylobacter jejuni (C. jejuni) is the leading cause of human bacterial gastroenteritis worldwide and has a major impact on global public health. The objective of the present study was to conduct whole genome sequencing (WGS) to determine the genetic diversity, virulence factors, and determinants of antimicrobial resistance of C. jejuni during a 3-year surveillance period in Beijing, China. Methods: A total of 184 clinical isolates were obtained from sentinel hospital surveillance between 2019 and 2021. Antimicrobial susceptibility testing was conducted using the agar dilution method. WGS was employed to characterize the 184 C. jejuni strains. Results: Multilocus sequence typing analysis revealed high genetic diversity among the 184 C. jejuni strains, identifying 71 sequence types (STs) and 19 clonal complexes (CCs). The most prevalent ST was ST760 (6.5%), and the most common CC was CC21 (24.5%), consisting of 11 STs. High resistance rates were observed for ciprofloxacin (76.6%), nalidixic acid (76.1%), and tetracycline (71.2%). A total of 77 C. jejuni isolates (41.8%) exhibited multidrug resistance with 43 resistance patterns. Virulome analysis disclosed the differential distribution of virulence factors related to adherence, colonization, chemotaxis, as well as lipo-oligosaccharide and capsular polysaccharide biosynthesis. Resistome analysis demonstrated widespread resistance to quinolones and tetracycline, but low rates of macrolides resistance. The phylogeny, based on whole genome single nucleotide polymorphisms, indicated a high degree of clonality and grouped the C. jejuni strains into six clades. Closely related isolates that were part of a genetic cluster mostly shared a homogenous clonal complex. Conclusions: The present study emphasizes the rising resistance to quinolones and tetracycline, as well as the virulence potential and diverse genotypes identified among C. jejuni strains isolated from diarrheal patients in Beijing.

Dietary Intake of Multiple Nutrient Elements and Associated Health Effects in the Chinese General Population from a Total Diet Study.

Nutrient elements are essential for human health. The intake of nutrient elements (Na, K, Ca, Mg, P, Mn, Fe, Zn, Cu, Se, Mo, and Cr) in the general Chinese population was comprehensively evaluated via a recent total diet study (2016-2019), covering more than two-thirds of the total population. The contents of nutrient elements in 288 composite dietary samples were determined by ICP-MS. The dietary sources, regional distribution, the relationship with the earth's crust, dietary intake, and health effects were discussed. Plant foods were the main source of both macro-elements and trace elements, accounting for 68-96% of total intake. Trace elements in food were compatible with their abundance in the earth's crust. Na intake reduced by 1/4 over the last decade but was still high. The average intake of Ca, Mg, Zn, and Se did not reach the health guidance values, while the average intake of K, P, Mn, Fe, Cu, Mo, and Cr fell within a reasonable range. No element exceeded the UL. However, an imbalance was identified in the dietary Na/K ratio and Ca/P ratio. This paper provides a most recent and national-representative assessment of nutrient element intake, indicating the significance of salt reduction and dietary structure optimization for the population.

Chronic Health Risk for Chinese Adults and Breastfed Infants on Dietary Exposure to Chlorothalonil and Its Main Metabolite.

This study presents the first nationwide study on the chronic health risks of chlorothalonil and its metabolite (4-OH-chlorothalonil) for Chinese adults and breastfed infants via dietary intake. The determination of chlorothalonil and 4-OH-chlorothalonil in dietary samples was accomplished by cold-induced liquid-liquid extraction using liquid chromatography─high-resolution mass spectrometry. Chlorothalonil and 4-OH-chlorothalonil were detected in 43.1 and 46.1% of total dietary samples, respectively, while only 4-OH-chlorothalonil was detected in 100% of breast milk samples. Chlorothalonil and 4-OH-chlorothalonil residues in dietary samples of Northwest China and Shandong regions were higher in comparison to those of other regions. No correlation between 4-OH-chlorothalonil residues in breast milk and adult daily dietary intake to total chlorothalonil indicates the presence of other exposure routes besides dietary exposure. Furthermore, a residue analysis of 4-OH-chlorothalonil in breast milk between urban and rural areas in all sampling locales showed no statistical difference (p > 0.05). The findings of this study reveal that the chronic health risks caused by dietary exposure to chlorothalonil and 4-OH-chlorothalonil are low for Chinese adults and breastfed infants.

Epidemiological features, genomic characteristics, and origin tracing of the COVID-19 outbreaks in Beijing from January to September 2022.

Different variants of severe acute respiratory syndrome coronavirus 2 have been discovered globally. At present, the Omicron variant has been extensively circulated worldwide. There have been several outbreaks of the Omicron variant in China. Here, we investigated the epidemiologic, genetic characteristics, and origin-tracing data of the outbreaks of COVID-19 in Beijing from January to September 2022. During this time, 19 outbreaks occurred in Beijing, with the infected cases ranging from 2 to 2230. Two concern variants were detected, with eight genotypes. Based on origin tracing analysis, two outbreaks were from the cold-chain transmission and three from items contaminated by humans. Imported cases have caused other outbreaks. Our study provided a detailed analysis of Beijing's outbreaks and valuable information to control the outbreak's spread.

Polychlorinated dibenzo-p-dioxins and dibenzofurans and dioxin-like polychlorinated biphenyls in human milk from national human breast milk monitoring in 2016-2019 in China.

Human breast milk monitoring programs were recommended to be carried out to assess human body burden to persistent organic pollutants and their temporal trends. Thus, we conducted a national survey during the period of 2016-2019 to determine PCDD/Fs and dl-PCBs in human breast milk from China. The total TEQ amounts in the upper bound (UB) was in the range of 1.97 to 15.1 pg TEQ g-1 fat with a geometric mean (GM) of 4.50 pg TEQ g-1 fat. 2,3,4,7,8-PeCDF, 1,2,3,7,8-PeCDD, and PCB-126 were more predominant contributors with the percentage contribution of 34.2 %, 17.9 %, and 17.4 %, respectively. By comparison with our previous monitoring results, the total TEQ in breast milk sample of the present study is statistically lower than that in 2011 with a reduction of 16.9 % in the average (p < 0.05), and comparable to that in 2007. The estimated GM of dietary intake of total TEQ for the breastfed was 25.4 pg TEQ kg-1 body weight day-1 that was higher than that of the adult. It is therefore worthy to make more efforts to reduce amounts of PCDD/Fs and dl-PCBs in breast milk and to continue monitoring to further observe if the amount of these chemicals continue to decrease.

Penetration of Perfluorooctanesulfonate Isomers and Their Alternatives from Maternal Blood to Milk and Its Associations with Chemical Properties and Milk Primary Components.

Perfluorooctanesulfonate (PFOS) and its alternatives, including chlorinated polyfluorinated ether sulfonates (Cl-PFESAs), are mainly detected per- and polyfluoroalkyl substances (PFAS) in human samples such as milk. However, the mechanism of their blood to milk transfer was not well studied. Here, 145 paired maternal serum and human milk samples were analyzed for six PFOS isomers and Cl-PFESAs to evaluate the transfer efficiency from maternal serum to human milk (TEHM/MS). Besides physicochemical properties, this study for the first time evaluated the influencing effects of the primary components in human milk (carbohydrate, lipid, and protein) on TEHM/MS of PFAS. No significant association was observed between TEHM/MS and the albumin binding affinity of the compounds (p = 0.601), but TEHM/MS was significantly negatively correlated with the logarithmic octanol-water partition coefficients (r2 = 0.853, p = 0.001), the logarithmic membrane-water partition coefficients (r2 = 0.679, p = 0.012), and the carbohydrate contents in human milk. The effect of carbohydrate was further confirmed using in vitro tests. The negative associations between TEHM/MS and hydrophobicity, membrane passive permeability, and the carbohydrate content in human milk consistently indicated that passive diffusion through the paracellular route might be the main transfer pathway for PFOS and Cl-PFESAs from blood to milk in humans.