Panaji: A new study has found that the shipping industry is the biggest contributor to lead pollution in Goa’s air, raising concerns about environmental and public health. Researchers from the School of Environmental Studies, Jadavpur University, report that oil used by ships accounts for 32–34% of airborne lead in the state, making it the single largest human-made source of this toxic metal.The study, titled ‘Lead isotopes and trace metal signatures reveal shipping-derived atmospheric pollution in coastal Goa’ and published in the Science Direct Journal, analysed fine air particles known as PM10 and PM2.5. These are tiny enough to enter the lungs and bloodstream. By examining their chemical composition, the researchers were able to trace pollution back to its sources. Along with ships, vehicles were found to contribute significantly—not just through exhaust fumes but also from the wear and tear of tyres and brakes—while burning waste adds more harmful particles to the air.The researchers also highlighted the role of casino vessels operating on the Mandovi river, saying they add to pollution in an already stressed ecosystem. According to the University’s UGC assistant professor, Reshmi Das, these vessels increase sewage and solid waste in the river. She also raised concerns about air quality inside casino boats, especially where hookah or shisha is used.“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, and that 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 said.Das, along with PhD scholars Iravati Ray, Jariya Kayee and Aditi Majumdar from Nanyang Technological University, Singapore, and Chulalongkorn University, Bangkok, Thailand, worked on the research.However, the study makes it 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 adds 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 said.This overlapping exposure, experts say, makes the situation particularly concerning for both ecosystems and human health.
