The Tijuana River’s polluted waters don’t just contaminate Southern California’s beaches – they also release toxic gases and aerosols that travel far beyond the riverbanks, threatening the health of nearby communities, according to a new study. The Tijuana River Valley, straddling the US-Mexico border, faces a severe and worsening pollution crisis as untreated sewage, industrial waste, and toxic runoff flow into the Pacific, causing prolonged beach closures and persistent environmental health risks. While most concern has centered on direct contact with contaminated water, mounting evidence shows pollutants can aerosolize, becoming airborne and dispersing far beyond the riverbanks. This overlooked pathway means communities may face greater exposure through inhalation than through direct contact with contaminated water. With over half the global population living near waterways, understanding the impact of water pollution on air quality is an urgent yet understudied public health priority.

 

Building on previous research that traced airborne bacteria and chemical pollutants near the mouth of the Tijuana River in San Diego, California, and guided by community reports of foul odors and health symptoms of those who live near the river, Benjamin Rico and colleagues identified a turbulent stretch of the river as a likely hotspot for gas and aerosol emissions. This prompted the authors to use a mobile air quality lab to measure hydrogen sulfide (H₂S) – a toxic gas produced by the breakdown of sewage – as an airborne tracer of water pollution. They found that the record high dry-season flows of 2024 led to a significant spike in H₂S emissions, with nighttime peaks reaching 4500 parts per billion (ppb) – thousands of times above typical urban levels (<1 ppb). According to Rico et al., the findings highlight the impact that turbulent portions of contaminated rivers have on regional air quality. Because existing air quality models omit emissions from polluted rivers and estuaries, incorporating these pathways is critical for accurately predicting health impacts, addressing inhalation risks, and guiding mitigation. Moreover, the exceedingly high H₂S concentrations confirmed the validity of long-dismissed community observations, highlighting the disproportionate burden borne by marginalized communities. “Sustained monitoring, coordinated cross-border efforts, and leadership from federal, state, and local authorities are crucial to finally provide the protection and justice long denied to communities affected by this ongoing environmental and public health crisis,” Rico et al. write.

 

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When genetic testing reveals a rare DNA mutation, doctors and patients are frequently left in the dark about what it actually means. Now, researchers at the Icahn School of Medicine at Mount Sinai have developed a powerful new way to determine whether a patient with a mutation is likely to actually develop disease, a concept known in genetics as penetrance. The team set out to solve this problem using artificial intelligence (AI) and routine lab tests like cholesterol, blood counts, and kidney function. Details of the findings were reported in the August 28 online issue of Science. Their new method combines machine learning with electronic health records to offer a more accurate, data-driven view of genetic risk.

 

For African American patients undergoing mastectomy, the risk of complications and the postoperative appearance of the breast are among the important drivers of preferences about breast reconstruction, reports a study in the September issue of Plastic and Reconstructive Surgery®, the official medical journal of the American Society of Plastic Surgeons (ASPS). The journal is published in the Lippincott portfolio by Wolters Kluwer.

Metabolic health before and during pregnancy may have a bigger influence on risks for mother and baby than simply controlling weight gain. Data from a recent paper by Pennington Biomedical researchers indicates that pregnant women with metabolically unhealthy obesity were more likely to develop gestational diabetes than those who were metabolically healthy. The paper, “Metabolic Health and Heterogenous Outcomes of Prenatal Interventions: A Secondary Analysis of a Randomized Clinical Trial,” was published in the Journal of American Medical Association.