Ecotoxicity and genotoxicity of cadmium in different marine trophic levels * Maria D. Pavlaki * ,M  ario J. Araújo, Diogo N. Cardoso, Ana Rita R. Silva, Andreia Cruz, S  onia Mendo, Amadeu M.V.M. Soares, Ricardo Calado, Susana Loureiro Department of Biology & CESAM e Centre for Environmental and Marine Studies, University of Aveiro, 3810-193 Aveiro, Portugal article info Article history: Received 16 January 2016 Received in revised form 2 May 2016 Accepted 4 May 2016 Keywords: Acartia tonsa Palaemon varians Solea senagalensis DNA damage Comet assay Ionic cadmium abstract Cadmium ecotoxicity and genotoxicity was assessed in three representative species of different trophic levels of marine ecosystems e the calanoid copepod Acartia tonsa, the decapod shrimp, Palaemon varians and the pleuronectiform fish Solea senegalensis. Ecotoxicity endpoints assessed in this study were adult survival, hatching success and larval development ratio (LDR) for A. tonsa, survival of the first larval stage (zoea I) and post-larvae of P . varians, egg and larvae survival, as well as the presence of malformations in the larval stage of S. senegalensis. In vivo genotoxicity was assessed on adult A. tonsa, the larval and postlarval stage of P . varians and newly hatched larvae of S. senegalensis using the comet assay. Results showed that the highest sensitivity to cadmium is displayed by A. tonsa, with the most sensitive endpoint being the LDR of nauplii to copepodites. Sole eggs displayed the highest tolerance to cadmium compared to the other endpoints evaluated for all tested species. Recorded cadmium toxicity was (by increasing order): S. senegalensis eggs < P . varians post-larvae < P . varians zoea I < S. senegalensis larvae < A. tonsa eggs < A. tonsa LDR. DNA damage to all species exposed to cadmium increased with increasing con- centrations. Overall, understanding cadmium chemical speciation is paramount to reliably evaluate the effects of this metal in marine ecosystems. Cadmium is genotoxic to all three species tested and therefore may differentially impact individuals and populations of marine taxa. As A. tonsa was the most sensitive species and occupies a lower trophic level, it is likely that cadmium contamination may trigger bottom- up cascading effects in marine trophic interactions. © 2016 Elsevier Ltd. All rights reserved. 1. Introduction During the last 50 years, the environmental hazard of cadmium has been assessed in aquatic and soil ecosystems (Burger, 2008; Nordberg, 2009). This naturally occurring metal, is found both in water and soil/sediments at low concentrations due to natural processes, such as volcanic eruptions, natural crust erosion and also anthropogenic activities, such as mining and smelting (World Health Organization, 2003). Being a common by-product of zinc mining, cadmium often runoffs into aquatic systems (Environment Programme, 2008) and subsequently ends up in brackish and ma- rine environments (Chiodi-Boudet et al., 2013). This non-essential metal to life forms, is commonly toxic even at relatively low concentrations and can cause adverse effects due to its high bio- accumulation tendency (Chandurvelan et al., 2013a, 2012). Re- ported concentrations of cadmium in the marine environment ranging from less than 5 ng/L (World Health Organization, 2003) to an average of 40 ng/L in unpolluted surface waters (Ray, 1984), while up to 250 ng/L can be recorded in coastal areas of northern Europe (World Health Organization, 2003). This feature has been associated with riverine inputs and/or due to direct human impact (Elinder, 1985; World Health Organization, 2003). The International Agency for Research on Cancer (1993) clas- sifies cadmium as a human carcinogen and teratogen with probable mutagenic properties. Indeed, this metal can induce genotoxicity in organisms, such as DNA strand breaks, chromosomal aberrations and micronuclei formations (MN) (Sarkar et al., 2015). Cadmium contamination can trigger the production of reactive oxygen spe- cies (ROS) (Amirthalingam et al., 2013), which have been suggested to be the promoters of genotoxicity (Bertin and Averbeck, 2006). Nocuous effects of chemicals are usually foreshadowed by cellular * This paper has been recommended for acceptance by Harmon Sarah Michele. * Corresponding author. University of Aveiro, Department of Biology, Campus Universit ario de Santiago, 3810-193 Aveiro, Portugal. E-mail address: maria.pavlaki@ua.pt (M.D. Pavlaki). Contents lists available at ScienceDirect Environmental Pollution journal homepage: www.elsevier.com/locate/envpol http://dx.doi.org/10.1016/j.envpol.2016.05.010 0269-7491/© 2016 Elsevier Ltd. All rights reserved. Environmental Pollution 215 (2016) 203e212