Heavy metal contamination, distribution and source apportionment in the sediments from Kavvayi Estuary, South-west coast of India

Abstract

Heavy metal contamination in sediments poses serious threat to ecosystem and human health through food web. In this study, surface sediment samples from Kavvayi estuary were analyzed to understand the sources and pollution levels of heavy metals. The results revealed that the average contents (μg g⁻¹) of eight selected heavy metals followed the order of Mn (65–795) > Cr (30–442) > Co (30–250) > Ni (15–175) > Zn (20–120) > Cu (5–55) > Pb (5–40). Enrichment factor (EF) and contamination factor (CF) analyses revealed that Pb, Ni and Cr shows moderate pollution levels, whereas Co indicates severe pollution levels. The rests of the heavy metals (Zn, Cu and Mn) were at no to low pollution levels. The correlation matrix combined with multivariate principal component analysis suggests the heavy metals, except for Co, mainly originated from natural weathering and erosion of rocks and soils in the catchment. The results of this study provide a comprehensive assessment of heavy metal contamination in the sediments of the Kavvayi region. The result can aid the development of effective remediation strategies and improve government decision-making and coastal management.