Abstract:
Mangrove-associated coastal wetlands are
increasingly recognised internationally as sites of
microplastic accumulation, yet the extent to which this
has been documented for Sri Lanka has not been
established. This review synthesises literature published
between 2015 and 2025 on the occurrence, characteristics,
distribution, methodologies, and ecological implications
of microplastics in Sri Lankan mangrove-associated
ecosystems, distinguishing mangrove-specific studies
(sampling within a mangrove stand) from mangrove-
associated studies (sampling in nearby lagoons, estuaries,
or coastal habitats). Literature was identified through
accessible search platforms, institutional repositories,
and publicly available peer-reviewed publications;
because subscription databases were not directly queried,
the review is a structured literature review rather than a
full systematic PRISMA review, and its coverage should
not be read as exhaustive. Only three mangrove-specific
studies were found, concentrated in Negombo Lagoon
and five southern sites, while nine mangrove-associated
studies document microplastics in nearby lagoons, water,
sediment, and biota; four further coastal studies are
retained only as national context. Fibers and fragments
dominate reported particle shapes, and no Sri Lankan
study has sampled biota within a mangrove stand or
measured physical or chemical effects beyond ingestion.
The most pressing gaps relate to geographical coverage,
standardised reporting units, and field-based evidence of
ecological effect. Overall, the evidence demonstrates
documented contamination and, in lagoon biota,
documented ingestion, but not demonstrated ecological
damage within Sri Lankan mangroves; closing this gap
requires standardised, geographically distributed
sampling conducted directly within mangrove stands.
