Acute Effects of Exposure to Fine Particulate Matter and Its Constituents on Sex Hormone Among Postmenopausal Women — Beijing, Tianjin, and Hebei PLADs, China, 2018–2019

   A groundbreaking study has revealed a significant link between short-term exposure to fine particulate matter (PM2.5) and its components, and elevated sex hormone levels, particularly estradiol, in postmenopausal women. Utilizing data from over 1,000 participants in the highly polluted Beijing-Tianjin-Hebei region of China, this research marks a pivotal step in understanding the nuanced effects of air pollution on hormonal health beyond reproductive age. The study identified specific inorganic elements within PM2.5 — such as silver, arsenic, cadmium, mercury, lead, antimony, selenium, tin, thallium, and zinc — as key contributors to the increase in estradiol levels, suggesting a novel risk factor for hormone imbalance in postmenopausal women. These findings underscore the urgent need for interventions to mitigate air pollution exposure, particularly among vulnerable demographics. By highlighting the potential of PM2.5 to act as a xenobiotic that disrupts hormone levels, this research provides a critical foundation for future public health strategies aimed at reducing the adverse health impacts of air pollution on an often-overlooked population segment.

   For more information: https://weekly.chinacdc.cn/en/article/doi/10.46234/ccdcw2024.049

Antimicrobial Resistance Analysis and Whole-Genome Sequencing of Salmonella Isolates from Environmental Sewage — Guangzhou City, Guangdong Province, China, 2022–2023

   A recent study conducted in Guangzhou, China, highlights the alarming rise in antimicrobial resistance among two emerging Salmonella serotypes, S.1,4,[5],12:i:- and S. Rissen, isolated from untreated environmental sewage. Analyzing 35 S.1,4,[5],12:i:- and S. Rissen isolates, researchers utilized whole-genome sequencing to identify 183 antimicrobial resistance genes (ARGs), including the rare plasmid-mediated colistin resistance gene mcr-3.1. The study's findings reveal a high prevalence of multidrug resistance (MDR), with S.1,4,[5],12:i:- showing notable resistance to commonly used antibiotics such as ampicillin, streptomycin, and tetracycline, while S. Rissen isolates displayed 100% resistance to the same drugs. Both serotypes were sensitive to other critical antibiotics, suggesting potential treatment options. The research underscores the need for comprehensive strategies integrating surveillance, clinical management, and public health interventions to combat the spread of drug-resistant pathogens. By highlighting the genetic relationships and resistance patterns of these Salmonella strains, the study provides essential insights for informing epidemiological data, improving clinical practices, and developing effective public health strategies on both domestic and international scales.

   For more information: https://weekly.chinacdc.cn/en/article/doi/10.46234/ccdcw2024.050

Molybdenum Concentration and the Risk of Spontaneous Preterm Birth: A Nested Case-Control Study — Beijing Municipality, China, 2018–2020

   A recent study conducted within the Beijing Birth Cohort Study framework analyzed the link between maternal plasma Molybdenum (Mo) levels during pregnancy and the risk of spontaneous preterm births (SPB), which constitute 60–70% of all preterm births and are a significant cause of neonatal fatalities. The nested case-control study included 236 women who experienced SPB and 236 who gave birth after 37 weeks, with plasma samples collected during the first and third trimesters. Findings revealed that higher maternal Mo concentrations in the first trimester were significantly associated with an increased risk of SPB, with an odds ratio (OR) of 2.074 for Mo levels ≥2.584 ng/mL, adjusted for maternal age, ethnicity, pre-pregnancy body mass index (PPBMI), parity, mode of delivery, education, and income levels. The study highlights the need for awareness around Mo consumption and environmental exposure during early pregnancy due to its potential contribution to SPB risk. Given the lack of a defined reference range for blood Mo concentrations in pregnant women across various regions, the findings underscore the importance of vigilant monitoring of Mo levels during pregnancy, especially in areas with high Mo exposure. This study adds to the growing body of evidence on the impact of environmental and dietary factors on pregnancy outcomes and emphasizes the need for further research to clarify the mechanisms by which Mo affects SPB risk.

   For more information: https://weekly.chinacdc.cn/en/article/doi/10.46234/ccdcw2024.051

The Relationship Between the Atmospheric Environment and Road Traffic Fatalities — Shandong Province, China, 2012–2021

   A comprehensive study spanning from 2012 to 2021 in Shandong Province, China, underscores the significant impact of atmospheric conditions on road traffic fatalities, which totaled 163,863 cases. Correlational analysis revealed a positive association between road traffic deaths and both daily average and maximum temperatures, as well as with specific pollutants like particulate matter and nitrogen dioxide (NO2). Interestingly, while daily accumulated precipitation generally reduced fatalities, relative humidity increased pedestrian fatalities. Ridge regression analysis further elucidated these relationships, demonstrating that factors such as maximum wind speed and certain air pollutants (PM2.5, PM10, SO2, and NO2) either positively or negatively correlated with fatality rates across different victim subgroups. The findings highlight the intricate dynamics between weather conditions, air pollution, and road safety, suggesting that improved atmospheric environmental management and meteorological warning systems could significantly lower road traffic fatality rates. This research contributes valuable insights towards developing targeted interventions and policies aimed at enhancing road safety under varying atmospheric conditions.

   For more information: https://weekly.chinacdc.cn/en/article/doi/10.46234/ccdcw2024.052

Analysis and Monitoring of Indoor Radon Concentrations of 37 Kindergartens — Beijing Municipality, China, 2023

   A comprehensive study monitoring indoor radon levels across 37 kindergartens in Beijing has identified that nearly one-fifth (18.9%) exceeded the 100 Bq/m3 level considered relatively high for new buildings. Radar surveillance points were strategically placed in children’s play areas, sleeping quarters, and administrative offices to record varying levels of radon concentration on different floors, revealing the highest concentration on the ground floor. Despite all sites being below China’s current maximum indoor radon limit of 300 Bq/m3 for older buildings, these findings are concerning given children’s increased vulnerability to radon-induced carcinogenic effects due to their developing physiology and higher respiratory rates relative to their body weight. The study emphasizes the urgent need for focused radon control measures and tailored standards in educational settings to mitigate health risks to young children. Reinforcing the importance of this issue, radon’s link to lung cancer and potential association with childhood leukemia necessitates regular reassessment of radon levels and the adoption of targeted mitigation strategies in kindergartens. The study advocates for the establishment of a stringent national standard for regulating indoor radon concentrations in kindergartens to ensure a safer environment for the well-being of children.

   For more information: https://weekly.chinacdc.cn/en/article/doi/10.46234/ccdcw2024.053