Trace metals in water, sediment and bivalves of a tropical estuary, west coast of India

•Effect of Fe and Mn content in water, sediment and edible bivalves was investigated.•High variation in concentration of Fe and Mn was recorded in areas of sink of mining.•Concentration of trace metal in tissue of bivalves showed spatio-temporal differences.•The concentration of Fe in tissue was higher than the safe limit of WHO.•The bivalves can be used as indicator of metal pollution. Trace metal pollution was studied in water, sediment and three selected bivalves in Mandovi and Chapora estuaries of Goa. The trace metal in water and sediment of Mandovi was higher than in Chapora. The concentration in the tissues was in the range of 1205.2–2506.7ppm for Paphia malabarica, 1906.2–2802.6ppm for Perna viridis and 778.7–1607.5ppm for Saccostrea cucullata in Mandovi estuary. Tha values for Chapora were 199.4–625.8ppm for P. malabarica, 812.6–1220.2 for P. viridis and 392.5–418.6ppm for S. cucullata. The anthropogenic input of metal in Mandovi estuary appears to be mainly responsible for the high accumulation of trace metals. These bivalves have potential to serve as indicator for metal contamination in seafood of Goa.