PANAJI
The beaches in Goa have emerged as some of the most contaminated along India’s western coastline, with significantly high levels of toxic hydrocarbons found on microplastics, according to a study by the National Institute of Oceanography (NIO).
The study, which analysed samples from 14 beaches along the Eastern Arabian Sea coast covering Maharashtra, Goa and Karnataka, found that “the concentrations of 16 Polycyclic Aromatic Hydrocarbons (PAHs) in pellets were 1.9–29,500 ng/g in Goa,” the highest among the regions studied.
In comparison, the study noted that levels ranged between 0.6–22,900 ng/g in Mumbai and 0.8–21,400 ng/g in Karnataka, placing Goa at the upper end of contamination.
The study is been undertaken by scientists including P Gupta, M Saha, C Rathore, V Suneel, J de Boer and A Garg.
Explaining the findings, the study stated that “pellets consistently exhibited higher PAH loads, likely due to their smaller size, greater surface area, and prolonged environmental exposure,” making them more effective carriers of toxic pollutants.
For microplastic fragments, Goa recorded moderate contamination levels, with “16 PAHs ranging from 1–1,500 ng/g”, lower than Karnataka but higher than Mumbai, indicating differing pollution behaviour across microplastic types.
The researchers observed that “4–6 ring PAHs dominated”, pointing to high-temperature processes such as combustion. The study further added that “diagnostic ratios indicated a combination of pyrolytic, petroleum spills, and combustion activities,” highlighting multiple human-induced pollution sources along the coast.
The study raised concern over ecological risks, noting that “PAH was higher than TEL (threshold effect level) and ERL (effects range low), indicating a probable occasional biological impact.” However, it clarified that ‘lower PAH levels than PEL and ERM suggest no significant adverse effects on marine or human ecosystems’ at present.
Despite this, the study warned of emerging risks, stating that microplastics act as “effective sorbents for hydrophobic compounds” and can serve as carriers transporting pollutants across marine environments.
With Goa recording some of the highest PAH loads, the findings are significant for the State’s coastal health, especially given its dependence on tourism and fisheries.
The study concludes with a cautionary note, raising “urgent questions on how far these invisible threats can disperse, and what their long-term implications are for coastal ecosystems and public health,” signalling the need for closer monitoring and pollution control along Goa’s shoreline.
