0
Article ? AI-assigned paper type based on the abstract. Classification may not be perfect — flag errors using the feedback button. Tier 2 ? Original research — experimental, observational, or case-control study. Direct primary evidence. Sign in to save

Spatio-Temporal Dynamics of Microplastic Pollution in Water, Sediment, and Plankton of Ambattur Lake, India: Implications for Aquatic Health Risks

Journal of Environmental Risk Impact and Claims 2026
Janani Sridhar, Madhavi Mookkan, Saiyad Musthafa Mohamed, Balu Alagar Venmathi Maran, Sruthy Shini, Muruganandam Muthiah, Anupama Vijay

Summary

Scientists studying an Indian lake found that tiny plastic bits (microplastics) are steadily building up year after year in the water, mud, and even the tiny organisms that fish eat—getting worse after rainy season washes more plastic in. While the total amount of plastic seemed low by traditional measures, a closer look at the specific plastic types revealed a much higher toxicity risk than expected, since some plastics break down into more harmful chemicals than others. This matters because these plastics enter the food chain through plankton, potentially working their way up to fish and eventually the people who eat them—suggesting we need smarter pollution tracking that

Study Type Environmental

Beyond addressing the abundance of microplastics (MPs) in freshwater ecosystems, this study focuses on significant polymer-specific toxicity risks, a dimension often overlooked in previous assessments. This research examines the spatiotemporal distribution of MPs in water, sediment, and plankton from Ambattur Lake, Tamil Nadu, India. The two-year cumulative average of MPs was 117.5 ± 21.3 MPs/L in water, 144.3 ± 28.6 MPs/kg in sediments, and 78.1 ± 12.6 MPs/m³ in plankton, with a 20–25% increase in overall burden in the second year, revealing a progressive accumulation of MPs. Seasonal patterns showed monsoonal influx with peak post-monsoon deposition due to intensified catchment runoff and resuspension. Fragments were predominant, primarily in blue and black. ATR-FTIR confirmed the presence of polyethylene terephthalate in water, nylon in sediments, and polyethylene and polypropylene in plankton, reflecting varied human-induced contributions. While the Pollution Load Index (PLI: 0.02–2.83) suggested minimal contamination, the Polymer Hazard Index (PHI: 3381.1; Hazard Level V) indicated significant risk due to polymer toxicity. Principal Component Analysis (56.1% variance) revealed a distinct shift from fiber-dominated pre-monsoon profiles to runoff-driven fragment clusters in the monsoon and post-monsoon phases, providing a visual link between hydrological events and polymer-specific toxicity risks. This study provides novel evidence on MP accretion in inland reservoirs and plankton communities, demonstrating that hazard-weighted risk assessment is critical for designing localized mitigation strategies, such as catchment filtration and discharge regulations, to safeguard the ecological integrity of urban freshwater ecosystems.

Share this paper