A new study has identified the shipping industry as the primary contributor to lead pollution in Goa's air, raising serious concerns about environmental and public health. Researchers from the School of Environmental Studies at Jadavpur University report that oil used by ships accounts for 32 to 34 percent of airborne lead in the state, making it the single largest human-made source of this toxic metal.
Study Details and Findings
The study, titled 'Lead isotopes and trace metal signatures reveal shipping-derived atmospheric pollution in coastal Goa' and published in the Science Direct Journal, analyzed fine air particles known as PM10 and PM2.5. These particles are small enough to enter the lungs and bloodstream. By examining their chemical composition, researchers traced pollution back to its sources. Alongside ships, vehicles were found to contribute significantly, not only through exhaust fumes but also from the wear and tear of tires and brakes. Additionally, the burning of waste adds more harmful particles to the air.
Role of Casino Vessels
The researchers also highlighted the role of casino vessels operating on the Mandovi River, stating that they add to pollution in an already stressed ecosystem. According to Reshmi Das, a UGC assistant professor at the university, these vessels increase sewage and solid waste in the river. She also raised concerns about air quality inside casino boats, particularly where hookah or shisha is used.
Das explained, "Hookah smoke is not filtered clean by water. The CDC notes that the charcoal used to heat hookah tobacco produces high levels of carbon monoxide, metals, and cancer-causing chemicals. Hookah smoke still contains nicotine, tar, and heavy metals after passing through water. Shisha contains heavy metals, including lead, arsenic, and chromium, which are inhaled during a session. The toxic smoke produced by burning tobacco and charcoal carries these heavy metals into the body. Hookah users have shown significantly higher levels of lead in their blood and urine."
Das collaborated with PhD scholars Iravati Ray, Jariya Kayee, and Aditi Majumdar from Nanyang Technological University in Singapore and Chulalongkorn University in Bangkok, Thailand, on this research.
Broader Environmental Issues
However, the study makes clear that casinos are only part of a larger problem. Untreated sewage from homes, restaurants, and commercial establishments continues to flow into the river, while urban wastewater carries microplastics into coastal waters. Pollution from mining activities and risks linked to oil spills and tanker traffic further add to the environmental burden, Das said.
The impact of this combined pollution is already visible in marine life. Researchers point to metal accumulation in edible shellfish, the presence of microplastics in fish, and declining nutritional quality of seafood. "For ecosystems, that means contamination moves across air, water, sediment, and food webs; for people, the likely concern is multi-pathway exposure through inhalation plus seafood consumption and water contact," Das added.
This overlapping exposure, experts say, makes the situation particularly concerning for both ecosystems and human health.
