Municipal trash dumped at an open landfill in Thailand risks filling a nearby tributary of the Mekong river with plastic waste whenever it is rainy or windy. Along India’s Ganges river, small sachets that used to wrap chewing tobacco are abundant, but are difficult to collect and dispose. A United Nations study tracing the origins of plastic pollution has identified key leakage hotspots in Asia. Plugging these gaps require not just broad-based bans on certain plastic products, but also policies that target sources of plastic pollution specific to each region, say researchers.
The UN study found that some top plastic leakage hot spots are illegal dump sites, including one along Thailand’s Mun river which feeds into the Mekong. Slums or smaller cities near waterways, with poor waste collection systems, pose another risk. Plastic waste from upstream also tends to accumulate in ports and piers.
Microplastics were also abundant in the Mekong and Ganges rivers, with all but three of 39 samples of water contaminated. The tiny substances come from a variety of products, including exfoliants in beauty creams. Water from downstream locations like the Vietnamese city of Can Tho contained significantly more microplastics. Yet the source of some 80 per cent of the microplastics could not be determined. Researchers said there was a need to build up a database of products from which microplastic trash originated.
Source: Straits Times
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