Leachates of micronized plastic toys provoke embryotoxic effects upon sea urchin Paracentrotus lividus * Maria Oliviero a, b, * , Tania Tato c , Simona Schiavo a, b , Ver  onica Fern  andez d , Sonia Manzo b , Ricardo Beiras c, e a Department of Science and Technology, Parthenope University of Naples, Centro Direzionale, Isola C4, 80143, Naples, Italy b Enea CR Portici, P.le E. Fermi, 1, 80055, Portici, Naples, Italy c ECIMAT, University of Vigo, Illa de Toralla, E-36331, Vigo, Galicia, Spain d Grupo Química Analítica Aplicada (QANAP), Instituto Universitario de Medio Ambiente (IUMA), Departamento de Química Analítica, Facultade de Ciencias, Universidade da Coru~ na, 15071, A Coru~ na, Spain e Department of Ecology and Animal Biology, University of Vigo, Campus Lagoas-Marcosende, 36200, Vigo, Galicia, Spain article info Article history: Received 12 October 2018 Received in revised form 22 January 2019 Accepted 23 January 2019 Available online 29 January 2019 Keywords: Microplastics Leachates PVC Seawater Marine larvae abstract Microplastics are defined as plastic fragments <5 mm, and they are found in the ocean where they can impact on the ecosystem. Once released in seawater, microplastics can be internalized by organisms due to their small size, moreover they can also leach out several additives used in plastic manufacturing, such as plasticizers, flame retardants, etc., resulting toxic for biota. The aim of this study was to test the toxicity of micronized PVC products with three different colors, upon Paracentrotus lividus embryos. In particular, we assessed the effects of micronized plastics and microplastic leachates. Results showed a decrease of larval length in plutei exposed to low concentrations of micronized plastics, and a block of larval development in sea urchin embryos exposed to the highest dose. Virgin PVC polymer did not result toxic on P. lividus embryos, while an evident toxic effect due to leached substances in the medium was observed. In particular, the exposure to leachates induced a development arrest immediately after fertilization or morphological alterations in plutei. Finally, PVC products with different colors showed different toxicity, probably due to a different content and/or combination of heavy metals present in coloring agents. © 2019 Elsevier Ltd. All rights reserved. 1. Introduction The rapid increase in plastic production and subsequent disposal represent a real concern for environment health (Lusher, 2015). In 2016, world production of plastic materials was 317 million tons (Europe, 2017). Estimation of 10% of plastic produced annually ends up in the ocean, contributing to 60e80% of all marine debris (Derraik, 2002). Plastic products, fragments and micro- plastics are found in the open ocean; on the sea surface, in sedi- ments, and in marine organisms (Barnes et al., 2009; Law and Thompson, 2014). Generally, microplastics are defined as any plastic fragment <1 mm (Browne et al., 2011; Van Cauwenberghe et al., 2013) or <5mm (Arthur et al., 2009; Wright et al., 2013). Moreover, microplastics can also be divided into “large micro- plastics” (1e5 mm) and “small microplastics” (20 mme1 mm) (Eriksen et al., 2014; Hanke et al., 2013; Hanvey et al., 2017). Several authors reported microplastics ingestion in marine worms (Besseling et al., 2012), bivalves (Browne et al., 2008; Von Moos et al., 2012) and crustaceans (Ugolini et al., 2013). Micro- plastics ingestion can impact on survival in fish larvae (Mazurais et al., 2015) and marine crustaceans (Cole et al., 2015; Lee et al., 2013), while adverse effects at tissue and cellular levels were re- ported in bivalves (Von Moos et al., 2012). As reported by Gray and Weinstein (2017), microplastics impact is affected by several pa- rameters like size, shape and composition. Beside the potential effects of direct exposure to microplastics, toxic effects due to the additives leached out from microplastics are also reported for aquatic organisms (Bejgarn et al., 2015; Hermabessiere et al., 2017). In plastic products the basic polymer is compounded with different additives such as plasticizers, flame retardants, antioxidants, pig- ments, etc., that improved the polymer performance (Hahladakis * This paper has been recommended for acceptance by Maria Cristina Fossi. * Corresponding author. Department of Science and Technology, Parthenope University of Naples, Centro Direzionale, Isola C4, 80143, Naples, Italy. E-mail address: maria.oliviero@uniparthenope.it (M. Oliviero). Contents lists available at ScienceDirect Environmental Pollution journal homepage: www.elsevier.com/locate/envpol https://doi.org/10.1016/j.envpol.2019.01.098 0269-7491/© 2019 Elsevier Ltd. All rights reserved. Environmental Pollution 247 (2019) 706e715