Plastic transport in a complex confluence of the Mekong River in Cambodia

December 6, 2021


Plastic transport in a complex confluence of the Mekong River in Cambodia


Charlotte J Haberstroh, Mauricio E Arias, Zhewen Yin, Ty Sok and Michael C Wang




Charlotte J Haberstroh et al 2021 Environ. Res. Lett. 16 095009


Field data on plastic pollution is extremely limited in Southeast Asian rivers. Here we present the
first field measurements of plastic transport in the Mekong, based on a comprehensive monitoring
campaign during the monsoon season in the confluence of the Mekong, Tonle Sap, and Bassac
rivers around Cambodia’s capital (Phnom Penh). For improved accuracy in the estimation of
plastic loads and distribution, we combined Neuston net multipoint cross-sectional water
sampling with acoustic Doppler current profiler high resolution measurements. During the wet
season, around 2.03 × 105 kg d −1 of plastic were released from Phnom Penh into the Mekong,
equivalent to 89 g −1
, or 42% of all plastic waste generated in the city. Most plastic mass
moved downstream at the surface. A smaller portion of plastics is mixed deep into the water
column, potentially retained in the rivers, breaking down and resuspending over time. Overall,
plastic waste from Phnom Penh and transported by the Mekong is a significant contribution to
Southeast Asia’s plastic release into the ocean. This pollution represents a crucial risk to people in
the region, as their livelihoods depend on fisheries from these water bodies.