Do endocrine disrupting chemicals threaten Mediterranean swordfish? Preliminary results of vitellogenin and Zona radiata proteins in Xiphias gladius M. Cristina Fossi a, *, Silvia Casini b , Stefania Ancora b , Alessandra Moscatelli c , Antonella Ausili d , Giuseppe Notarbartolo-di-Sciara d a Department of Animal Biology and Marine Ecology, University of Messina, Messina, Italy b Department of Environmental Science, University of Siena, Siena, Italy c Institute of Botany, University of Messina, Messina, Italy d ICRAM, Rome, Italy Received 9 January 2001; received in revised form 19 April 2001; accepted 5 May 2001 Abstract Endocrine Disrupting Chemicals (EDCs) have the potential to alter hormone pathways that regulate reproductive processes in wildlife and fishes. In this research the hypothesis that Mediterranean top predator species (such as large pelagic fish) are potentially at risk due to EDCs is investigated. These marine organisms tend to accumulate high concentrations of EDCs such as polyhalogenated aromatic hydrocarbons (PHAHs). The potential effects of EDCs on a fish species of commercial interest, the top predator Xiphias gladius (swordfish), were investigated using vitellogenin (Vtg) and Zona radiata proteins (Zrp) as diagnostic and prognostic biomarkers. Dramatic induction of typically female proteins (Vtg and Zrp) was detected by ELISA and Western Blot in adult males of the species. These results are the first warning of the potential risk for reproductive function of Mediterranean top predators, and suggest the need for continuous monitoring of this fragile marine environment. # 2001 Elsevier Science Ltd. All rights reserved. Keywords: Endocrine Disrupting Chemicals (EDCs); Mediterranean Sea; Xiphias gladius (swordfish); Biomarkers; Vitellogenin; Zona radiata proteins Marine Environmental Research 52 (2001) 477–483 www.elsevier.com/locate/marenvrev 0141-1136/01/$ - see front matter # 2001 Elsevier Science Ltd. All rights reserved. PII: S0141-1136(01)00107-6 * Corresponding author. Department of Enviromental Science, University of Siena, Via Mattioli 4, 53100 Siena, Italy. Tel.: +39-0577-232913; fax: +39-0571-652818. E-mail address: cdfos@tin.it (M. C. Fossi).