title: Are whale sharks exposed to persistent organic pollutants and plastic pollution in the Gulf of California (Mexico)? First ecotoxicological investigation using skin biopsies.
abstract: The whale shark (Rhincodon typus) is an endangered species that may be exposed to micro- and macro-plastic ingestion as a result of their filter-feeding activity, particularly on the sea surface. In this pilot project we perform the first ecotoxicological investigation on whale sharks sampled in the Gulf of California exploring the potential interaction of this species with plastic debris (macro-, micro-plastics and related sorbed contaminants). Due to the difficulty in obtaining stranded specimens of this endangered species, an indirect approach, by skin biopsies was used for the evaluation of the whale shark ecotoxicological status. The levels of organochlorine compounds (PCBs, DDTs), polybrominated diphenyl ethers (PBDEs) plastic additives, and related biomarkers responses (CYP1A) were investigated for the first time in the whale shark. Twelve whale shark skin biopsy samples were collected in January 2014 in La Paz Bay (BCS, Mexico) and a preliminary investigation on microplastic concentration and polymer composition was also carried out in seawater samples from the same area. The average abundance pattern for the target contaminants was PCBs>DDTs>PBDEs>HCB. Mean concentration values of 8.42ng/g w.w. were found for PCBs, 1.31ng/g w.w. for DDTs, 0.29ng/g w.w. for PBDEs and 0.19ng/g w.w. for HCB. CYP1A-like protein was detected, for the first time, in whale shark skin samples. First data on the average density of microplastics in the superficial zooplankton/microplastic samples showed values ranging from 0.00items/m3to 0.14items/m3. A focused PCA analysis was performed to evaluate a possible correlation among the size of the whale sharks, contaminants and CYP1A reponses. Further ecotoxicological investigation on whale shark skin biopsies will be carried out for a worldwide ecotoxicological risk assessment of this endangerd species.
authors.affiliation: Department of Physical, Earth and Environmental Sciences, University of Siena, Via Mattioli 4, 53100 Siena, Italy.
authors.forename: Maria Cristina
authors.initials: MC
authors.lastname: Fossi
authors.affiliation: Department of Physical, Earth and Environmental Sciences, University of Siena, Via Mattioli 4, 53100 Siena, Italy. Electronic address: matteo.baini@unisi.it.
authors.forename: Matteo
authors.initials: M
authors.lastname: Baini
authors.affiliation: Department of Physical, Earth and Environmental Sciences, University of Siena, Via Mattioli 4, 53100 Siena, Italy.
authors.forename: Cristina
authors.initials: C
authors.lastname: Panti
authors.affiliation: Department of Physical, Earth and Environmental Sciences, University of Siena, Via Mattioli 4, 53100 Siena, Italy.
authors.forename: Matteo
authors.initials: M
authors.lastname: Galli
authors.affiliation: Department of Instrumental Analysis and Environmental Chemistry. Institute of Organic Chemistry (IQOG-CSIC). Juan de la Cierva 3, 28006 Madrid, Spain.
authors.forename: Begoña
authors.initials: B
authors.lastname: Jiménez
authors.affiliation: Department of Instrumental Analysis and Environmental Chemistry. Institute of Organic Chemistry (IQOG-CSIC). Juan de la Cierva 3, 28006 Madrid, Spain.
authors.forename: Juan
authors.initials: J
authors.lastname: Muñoz-Arnanz
authors.affiliation: Department of Physical, Earth and Environmental Sciences, University of Siena, Via Mattioli 4, 53100 Siena, Italy.
authors.forename: Letizia
authors.initials: L
authors.lastname: Marsili
authors.affiliation: ISPRA, Institute for Environmental Protection and Research, Via V. Brancati 48, 00144 Rome, Italy.
authors.forename: Maria Grazia
authors.initials: MG
authors.lastname: Finoia
authors.affiliation: Tiburon Ballena Mexico proyecto de ConCiencia Mexico AC, La Paz, BCS, Mexico.
authors.forename: Dení
authors.initials: D
authors.lastname: Ramírez-Macías
mesh_terms: D000818:Animals; D015415:Biomarkers / Q000378:metabolism; D001706:Biopsy / Q000662:veterinary; D000072461:Cytochrome P450 Family 1 / Q000378:metabolism; D003634:DDT / Q000032:analysis / Q000633:toxicity; D056727:Endangered Species; D004781:Environmental Exposure / Q000009:adverse effects*; D004784:Environmental Monitoring; D005260:Female; D029941:Fish Proteins / Q000378:metabolism; D055768:Halogenated Diphenyl Ethers / Q000032:analysis / Q000633:toxicity; D008297:Male; D008800:Mexico; D010140:Pacific Ocean; D010573:Pesticide Residues / Q000032:analysis / Q000633:toxicity; D010865:Pilot Projects; D010969:Plastics / Q000032:analysis / Q000633:toxicity*; D011078:Polychlorinated Biphenyls / Q000032:analysis / Q000633:toxicity; D025341:Principal Component Analysis; D012623:Seawater / Q000737:chemistry; D012754:Sharks / Q000254:growth & development / Q000502:physiology*; D012867:Skin / Q000737:chemistry / Q000187:drug effects* / Q000254:growth & development / Q000378:metabolism; D014874:Water Pollutants, Chemical / Q000032:analysis / Q000633:toxicity*; D014876:Water Pollution / Q000009:adverse effects*
chemical_list: D015415:Biomarkers; D029941:Fish Proteins; D055768:Halogenated Diphenyl Ethers; D010573:Pesticide Residues; D010969:Plastics; D014874:Water Pollutants, Chemical; D003634:DDT; D011078:Polychlorinated Biphenyls; D000072461:Cytochrome P450 Family 1
keywords: CYP1A; Gulf of California; OCs; PBDEs; Plastic pollution; Whale shark