Abstract:
Microplastic (MP) pollution is often referred to as the invisible threat of our era due
to its minute size. Microplastics are defined as plastic particles less than 5 mm in size
and can be transported across various ecosystems, including the atmosphere. They
also have the potential for bioaccumulation and biomagnification within food chains.
This study investigates microplastic pollution in Bolgoda Lake and examine the
temporal variation of microplastics during the wet and dry seasons. Fifteen water
samples were collected from randomly selected different locations across the lake
during both seasons, with duplicates taken to ensure accuracy. A total of 25 liters of
water were filtered using a 300 µm sieve, and the residue was collected for analysis.
This residue underwent a digestion process followed by density separation. The
extracted microplastics were then observed using a stereo microscope. The results
indicated that the wet season exhibited a higher abundance of microplastics compared
to the dry season. The concentration of microplastics in surface water was higher
during the wet season (372 ± 143 MPs/m³) than in the dry season (252 ± 198
MPs/m³). In both seasons, microfibers were the predominant type of microplastic
observed. Regarding color distribution, the microplastics observed during the wet
season followed this order: Black > Red > Blue > Transparent > Green > Yellow >
White. A similar pattern was found during the dry season, with the order being: Black
> Red > Blue > Green > Transparent > Yellow > White. Results further indicated that
areas near urban development recorded a higher abundance of microplastics
compared to more isolated regions. This study highlights that Bolgoda Lake exhibits
the highest concentration of microplastics in its surface waters. These findings
provide crucial baseline data for understanding the sources, threats, and seasonal
distribution of microplastic pollution in Bolgoda Lake and provide valuable insights
for policymakers, researchers, and local communities.
