Research on microplastics must be harmonized. Therefore, we thoroughly evaluated in the Association of Southeast Asian Nations (ASEAN) region, addressing challenges and priorities in protocol harmonization and microplastics research promotion. Of the 615 papers searched by the Web of Science, 164 were used for this systematic review. The number of ASEAN research articles has increased over time. Examination of research protocols in various sampling environments revealed several challenges: 1) Disparities in access to sampling locations affect the research extent; 2) Outdated protocols and limited access to technologies such as FTIR (Fourier-transform infrared) spectroscopy result in less harmonized and potentially lower-quality data; and 3) Insufficiently detailed methods and QA/QC information hampers comparability. We offer procedure updates to overcome these limitations and cover environmental microplastic study gaps. Other countries in the Global South may encounter similar challenges, making this review a valuable contribution to advancing global microplastics research and fostering international collaboration.
Southeast (SE) Asia is a highly biodiverse region, yet it is also estimated to cumulatively contribute a third of the total global marine plastic pollution. This threat is known to have adverse impacts on marine megafauna, however, understanding of its impacts has recently been highlighted as a priority for research in the region. To address this knowledge gap, a structured literature review was conducted for species of cartilaginous fishes, marine mammals, marine reptiles, and seabirds present in SE Asia, collating cases on a global scale to allow for comparison, coupled with a regional expert elicitation to gather additional published and grey literature cases which would have been omitted during the structured literature review. Of the 380 marine megafauna species present in SE Asia, but also studied elsewhere, we found that 9.1 % and 4.5 % of all publications documenting plastic entanglement (n = 55) and ingestion (n = 291) were conducted in SE Asian countries. At the species level, published cases of entanglement from SE Asian countries were available for 10 % or less of species within each taxonomic group. Additionally, published ingestion cases were available primarily for marine mammals and were lacking entirely for seabirds in the region. The regional expert elicitation led to entanglement and ingestion cases from SE Asian countries being documented in 10 and 15 additional species respectively, highlighting the utility of a broader approach to data synthesis. While the scale of the plastic pollution in SE Asia is of particular concern for marine ecosystems, knowledge of its interactions and impacts on marine megafauna lags behind other areas of the world, even after the inclusion of a regional expert elicitation. Additional funding to help collate baseline data are critically needed to inform policy and solutions towards limiting the interactions of marine megafauna and plastic pollution in SE Asia.