Contaminants such as bacteria, viruses and chemical compounds in polluted coastal waters transfer to the atmosphere in sea spray aerosol formed by breaking waves and bursting bubbles.
Researchers from Scripps Institution of Oceanography at UC San Diego studied the impact of untreated sewage being diverted into the Tijuana River, which lies on the US-Mexico border, and flows into the ocean in south Imperial Beach in San Diego.
“We’ve shown that up to three-quarters of the bacteria that you breathe in at Imperial Beach are coming from aerosolisation of raw sewage in the surf zone,” said lead researcher Kim Prather.
“Coastal water pollution has been traditionally considered just a waterborne problem. People worry about swimming and surfing in it but not about breathing it in, even though the aerosols can travel long distances and expose many more people than those just at the beach or in the water.”
The team sampled coastal aerosols at Imperial Beach and...