Joe Brown’s research is largely focused on water contamination and its impact on public health. He travels to communities around the world measuring microbes in each environment to gather exposure data and determines what it means for the health and safety of residents. In a recent trip to India, Brown found aerosolized Giardia and Salmonella, pathogens not normally known to be transmitted via air. This discovery creates a new challenge in environmental engineering, one where microbes associated with water and sanitation are transmitted via the air (aerosols), potentially leading to new pathways of disease transmission.
When Joe Brown went to India last summer, he was hoping to collect samples that could help answer some questions he’d been thinking about for a while. His years studying sanitation and global health had given him the idea that the open sewers and overflowing latrines common in the dense cities of the developing world could be linked with disease through an unusual mechanism: airborne transmission of pathogens.
Acidic sulfur emissions from power plants have been rapidly declining over the past decade, and the neutralizing base – ammonia – is emitted from a different source, and has not declined. This has led many atmospheric scientists to assume that the ambient sulfate particles we all breathe are becoming less acidic and therefore less toxic. But a new study shows this intuitive expectation hasn’t happened, at least not in the Southeast United States, where the remaining sulfate particles appear to be as acidic as ever.