http://irgu.unigoa.ac.in/drs/handle/unigoa/5627 Tue, 07 Apr 2026 11:46:23 GMT 2026-04-07T11:46:23Z http://irgu.unigoa.ac.in/drs/handle/unigoa/7807 Assessment of microplastic contamination and associated risks in agricultural soils: a case study along the National Highway-66, Goa, India Chodankar, R.; Kalangutkar, N.G. Agricultural soils near major transportation corridors increasingly act as repositories for anthropogenic debris, yet the dynamics of this contamination in tropical paddy fields remain under-researched. This study investigates the abundance, morpho-chemical characteristics, and calculated ecological risks of microplastics in paddy field soils along National Highway 66 in Goa, India. Using Raman spectroscopy, scanning electron microscopy-energy dispersive X-ray spectroscopy (SEM-EDS), and standardized hazard indices, microplastic contamination was found to be ubiquitous, with concentrations ranging from 250 to 423 MP/kg (mean: 336.7 plus-minus 55.47 MP/kg). Population density and proximity to urban centers were key drivers of accumulation, with low-lying paddy regions functioning as depositional sinks for pollutants transported via runoff. Morphological analysis revealed a predominance of fibers (63 percent) and fine-sized particles (0.1-0.063 mm), indicating high potential for soil mobility. Polypropylene (51.85 percent) and polycarbonate (17.59 percent) were the dominant polymers identified. Notably, while the study area is traffic-influenced, tire-wear particles were not detected within the analytical range of the Raman technique employed, with the profile instead reflecting agricultural and consumer-related inputs. SEM analysis highlighted extensive surface weathering, while elemental profiling confirmed the adsorption of heavy metals (Pb, Cu, Fe), establishing these particles as active vectors for contaminants. Ecological risk assessments using the Polymer Hazard Index (PHI), Pollution Load Index (PLI), and Potential Ecological Risk Index (PERI) demonstrated a disconnect between abundance and hazard. These findings suggest that mitigation must prioritize hazard-weighted assessment over simple abundance monitoring to protect agricultural soil health. Thu, 01 Jan 2026 00:00:00 GMT http://irgu.unigoa.ac.in/drs/handle/unigoa/7807 2026-01-01T00:00:00Z http://irgu.unigoa.ac.in/drs/handle/unigoa/7773 Life cycle assessment of whiteleg shrimp farming in earthen vs. HDPE-lined ponds in India Mayekar, T.S.; Paramesha, V.; Sreekanth, G.B.; Rivonker, C.U.; Parveen Kumar Whiteleg shrimp (Penaeus vannamei) farming has expanded rapidly worldwide, contributing significantly to global seafood supply. However, concerns remain about its environmental impacts, particularly in India-a major exporter with diverse production systems. High-Density Polyethylene (HDPE)-lined ponds and earthen ponds are widely used, but their comparative environmental performance has not been comprehensively evaluated. This study aimed to quantify and compare the environmental impacts of intensive HDPE-lined and semi-intensive earthen pond shrimp farming systems along India's west coast. A cradle-to-farm-gate Life Cycle Assessment (LCA) was conducted using SimaPro software and the ReCiPe 2016 Midpoint method. Primary data were collected from 20 farms and one hatchery, covering seed production, feed use, and energy consumption. Environmental impacts were assessed across multiple categories, including Global Warming Potential (GWP), Terrestrial Acidification Potential (AC), and Marine Eutrophication Potential (EU). Results showed that HDPE-lined ponds had significantly higher GWP (369.04 vs. 268.06 kg CO sub(2) eq) and AC (1.20 vs. 0.94 kg SO sub(2) eq) per tonne of shrimp compared to earthen ponds, but lower EU (0.03 vs. 0.05 kg N eq). Seed production, electricity use, and feed emerged as the primary contributors to environmental impacts. Findings suggest that transitioning from HDPE-lined to earthen pond systems, adopting renewable energy sources such as solar aeration, and replacing fishmeal with plant-based alternatives could substantially improve the sustainability of Indian shrimp aquaculture. Wed, 01 Jan 2025 00:00:00 GMT http://irgu.unigoa.ac.in/drs/handle/unigoa/7773 2025-01-01T00:00:00Z http://irgu.unigoa.ac.in/drs/handle/unigoa/7770 Microplastics in sediment of the tropical (Mandovi) estuary, India: Physical pollutant and vectors of metals Mahato, V.; Nasnodkar, M.R. Microplastics have emerged as pervasive pollutants in marine environments, originating from the degradation of larger plastic debris and direct inputs from anthropogenic sources. Their small size, persistent nature and low density enable wide dispersion via coastal currents, leading to accumulation in estuarine sediments through hydrodynamic processes. The present study investigated abundance, spatial distribution, and pollution levels of microplastics in surface sediment of the Mandovi Estuary, Goa, with particular emphasis on their role in metal adsorption. Fiber-type was the predominant shape ranging from 53.02 percent - 94.61 percent of microplastics in sediment contributed mainly from fishing activities and cloth cleaning waste. Among polymer types, polyethylene (PE) was consistently dominant and present across all sampling stations (M1-M8), whereas polypropylene (PP) was restricted to station M5, indicating localized input sources. The prevalence and severity of fiber pollution were validated through the Coefficient of Microplastic Impact (CMPI), revealing maximum to extreme levels of pollution. The Pollution Load Index (PLI) further confirmed significant microplastic pollution in intertidal sediment across lower to middle regions of the Mandovi Estuary. The metals such as Zn and Fe displayed strong affinity for microplastic surfaces, as inferred from their elevated concentrations on isolated microplastic particles. It underscored the complex interactions between microplastic pollution and metal dynamics in the estuarine environment. The study highlighted the dual ecological threat posed by microplastics as both physical pollutants and vectors of metals. Thu, 01 Jan 2026 00:00:00 GMT http://irgu.unigoa.ac.in/drs/handle/unigoa/7770 2026-01-01T00:00:00Z http://irgu.unigoa.ac.in/drs/handle/unigoa/7768 Surface water assessment of microplastic contamination at three beaches in North Goa, India Kalangutkar, N.G.; Mhapsekar, S.; Salgaokar, A. Microplastic (MP) contamination in aquatic environments poses a persistent and serious threat to ecosystem health, necessitating comprehensive investigations. This study examines MP pollution in the surface waters of the northern beaches of Goa, including Baga, Anjuna, and Vagator. Results revealed that all three beaches are contaminated with MPs, with an average abundance of 0.47 MP/L. Among them, Baga Beach exhibited the highest concentration (0.6 MP/L), followed by Anjuna (0.5 MP/L) and Vagator (0.3 MP/L). Fibres were the most dominant shape of MPs, while colourless (56.5 percent) and 0.3-1 mm (68.62 percent) MPs were prevalent across all beaches. Common polymers such as polyethylene terephthalate (PET), polyamide (PA), polypropylene (PP), polyethylene (PE), and polystyrene (PS) were identified in the water samples. Risk assessment indices, including the Pollution Load Index (PLI), Polymer Hazard Index (PHI), and Coefficient of Microplastic Impact (CMPI), highlighted varying levels of ecological risk. PLI values exceeding 1 indicated pollution at all beaches, while PHI categorized the risk at level V due to hazardous polymers like PA and PS. CMPI emphasized the extreme impact of fibres on coastal waters. Scanning Electron Microscopy (SEM) analysis revealed surface degradation and weathering of MPs, providing insights into their environmental fate. This study indicates the presence of MP contamination along the northern beaches of Goa, highlighting the need for continued monitoring and the implementation of preventive measures to mitigate potential environmental impacts. Furthermore, these findings provide a critical baseline for future research and contribute to the formulation of strategies to manage and mitigate plastic pollution in coastal environments. Thu, 01 Jan 2026 00:00:00 GMT http://irgu.unigoa.ac.in/drs/handle/unigoa/7768 2026-01-01T00:00:00Z