Contents lists available at ScienceDirect Marine Pollution Bulletin journal homepage: www.elsevier.com/locate/marpolbul Baseline Health risk assessment and bioaccumulation of toxic metals in commercially important finfish and shellfish resources collected from Tuticorin coast of Gulf of Mannar, Southeastern India R. Rajaram ⁎ , A. Ganeshkumar, A. Vinothkannan Department of Marine Science, Bharathidasan University, Tiruchirappalli, 620 024, Tamil Nadu, India ARTICLE INFO Keywords: Toxic metals Fin and shellfishes Gulf of Mannar Southeastern India ABSTRACT The present study was mainly focused on the distribution of metals (Cd, Cu, Pb, and Zn) in commercially im- portant marine finfish and shellfish resources collected from the Tuticorin coast of the Gulf of Mannar, Southeastern India. Sixty-six species were collected in all four seasons for the analysis of metals. The order of bioaccumulation of metals in fishes is (Zn > Pb > Cu > Cd), in Crustaceans is (Zn > Pb > Cu > Cd), and in mollusks is (Pb > Zn > Cu > Cd). The human health risk assessment factors such as BCF, THQ, and HI were higher in most of the tested animals. The outcome of the present study will sound the alarm to the community about heavy metal contamination of sea foods. We conclude that continuous monitoring of the ecosystem is essential to the maintenance of the pristine ecosystem and quality of the seafood. Marine finfish and shellfish resources are regarded as an essential food supply of micro and macronutrients for human health. The coastal environment in southern India has been disturbed by various pollutants that include toxic metals and organic compounds, and these are re- leased by various metal-based and metal processing industries (Mathivanan and Rajaram, 2014; Arulkumar et al., 2017; Anandkumar et al., 2017, 2018; Rajaram et al., 2020). Heavy metals are persistent pollutants which are used in mining industries, pesticides, house-hold appliances, automobiles, dental amalgams, paints, photographic pa- pers, photo-chemicals, etc. (Lohani et al., 2008; WHO, 2004). They enter into the marine and coastal environment through different an- thropogenic and lithogenic activities. The most important activities which cause coastal pollution in Tamil Nadu occur due to the release of untreated industrial and domestic wastes; harbor activities such as dredging; cargo handling and transport; discarding of wastes from ships; spilling of cargos, chemicals, and metal ores; fishing and it re- lated activities, etc. (Anon, 2005; Mathivanan and Rajaram, 2014). Toxic metals enter the Gulf of Mannar region from various in- dustries like fertilizer and chemical industries, substantial quantities of heated effluents and release of fly-ash from thermal power plants, oil spill from the fishing harbor, and untreated or partially treated shrimp farm effluents. There are numerous industries situated in the Tuticorin coastal region including Tuticorin Alkalis and Chemicals Ltd., Tuticorin Thermal Power Station (TTPS), Southern Petrochemical Industries Corporation (SPIC), Indian Power Projects (at Vembar), etc. All these industries release their waste into the coastal region of the Gulf of Mannar and pose serious threats to the biodiversity (Murugesan et al., 1999). Tuticorin is one of the highly contaminated coastal cities located in the Gulf of Mannar coast of Southern India. One of the main pro- blems in this coast is metal pollution due to various anthropogenic activities over the past few years. However, very few studies have been carried out in specific locations like industrials sites (Easterson, 1998; Krishna Kumar et al., 2012; Magesh et al., 2011) and coastal regions (Jonathan and Ram Mohan, 2003; Garg et al., 2011), or to explore ground water (Krishna Kumar et al., 2012). There is no detailed study of toxic metals across the entire Tuticorin coast and their impact on the Gulf of Mannar. Hence, the present study covered the entire coast of Tuticorin for the estimation of toxic metals in commercially important finfish and shellfish resources due to various anthropogenic activities like sewage dumping, industrial, harbor and shipping activity, salt pan and fisheries activities, etc. In this study, we examine the level of metals Cd, Cu, Pb, and Zn in various food fishes collected from the Tuticorin coastal region from July 2014 to June 2016 (Fig. 1). In addition, the background concentrations of Cd, Cu, Pb, and Zn in water and sediment samples are also determined using standard methods (Table 2). To examine the toxic metals in finfishes and shellfishes, a total of 66 biological samples were collected from in and around Tuticorin coast of the Gulf of Mannar region. The samples were collected in sterile poly- thene bags and kept in a deep freezer (-20 °C) to prevent deterioration untill further analysis. The collected biological samples were https://doi.org/10.1016/j.marpolbul.2020.111469 Received 25 May 2020; Received in revised form 6 July 2020; Accepted 9 July 2020 ⁎ Corresponding author. E-mail address: drrajaram69@rediffmail.com (R. Rajaram). Marine Pollution Bulletin 159 (2020) 111469 Available online 18 July 2020 0025-326X/ © 2020 Elsevier Ltd. All rights reserved. T