River Pollution Can Become Airborne Via Sea Spray, Study Finds
Why in the news
A paper in Science Advances links dirty rivers to air quality: chemicals in untreated river water can leave the sea surface as aerosols that people inhale.
Key facts
- Site: Tijuana River (Mexico into the Pacific), studied by California scientists from January to March 2020.
- Method: daily seawater samples and air filtered on quartz-fibre filters at five spots along 35 km of coast.
- 12 compounds tracked: octinoxate (sunscreen), dibenzylamine (tyre additive), methamphetamine, other drugs, biocides and benzoylecgonine (sewage marker).
| Finding | Result |
|---|---|
| Higher in river-affected seawater | 10 of 12 compounds |
| Dirtiest aerosols | Sites beside the river |
| Emission per km of coast | About 1 kg octinoxate, 100 g methamphetamine |
Concerns and India link
- Long-term inhalation risks are unquantified, notably for fisherfolk and marginalised coastal groups.
- The Yamuna, Ganga and Mithi are heavily polluted; Mumbai, Chennai and Kolkata may face similar exposure.
- An environmental justice issue: the poor bear more of the burden.
Exam angle
- Journal: Science Advances; river: Tijuana; sewage proxy: benzoylecgonine.