title: Evaluation of PCBs and DDTs in endemic Iberian barbel Barbus bocagei (Steindachner, 1864) populations.
abstract: PCB and DDT levels were evaluated in populations of endemic Iberian barbel (Barbus bocagei) in the Jarama River in Spain via a pollution gradient from well-preserved areas upstream to contaminated downstream areas. Age structure, abundance, recruitment and levels of morphological abnormalities and ectoparasites were assessed. Upstream to downstream PCB concentrations ranged from 3.4 to 101.4 ng/g (ww) and from 0.9 to 19.6 ng/g ww for DDTs. The PCB pattern was dominated by the PCB 153, 138 and 180 congeners, and the less chlorinated ones had a relatively high contribution upstream. Barbels exposed to low PCB and DDT levels had a well-balanced population with a predominant cohort of young fish, indicating good recruitment. The most contaminated sites displayed a disrupted age distribution, where the proportion of young fish was clearly under-represented. Recruitment and total density of barbel populations decreased downstream where the highest PCB and DDT levels were found. In addition, a higher incidence of abnormalities and ectoparasites was observed at these sites. High concentrations of PCBs and DDTs most likely contribute to the reduction of Iberian barbel reproductive performance in the most contaminated sites, as shown by the disrupted age-distribution found in our study.
authors.affiliation: Department of Environmental Sciences, University of Castilla-La Mancha, E-45071 Toledo, Spain.
authors.forename: Graciela G
authors.initials: GG
authors.lastname: Nicola
authors.affiliation: Department of Zoology, Complutense University of Madrid, E-28040 Madrid, Spain.
authors.forename: Irene
authors.initials: I
authors.lastname: Parra
authors.affiliation: Department of Instrumental Analysis & Environmental Chemistry, Institute of Organic Chemistry, CSIC, E-28006 Madrid, Spain.
authors.forename: Mónica
authors.initials: M
authors.lastname: Sáez
authors.affiliation: Department of Zoology, Complutense University of Madrid, E-28040 Madrid, Spain.
authors.forename: Ana
authors.initials: A
authors.lastname: Almodóvar
authors.affiliation: Department of Instrumental Analysis & Environmental Chemistry, Institute of Organic Chemistry, CSIC, E-28006 Madrid, Spain. Electronic address: bjimenez@iqog.csic.es.
authors.forename: Begoña
authors.initials: B
authors.lastname: Jiménez
mesh_terms: D000818:Animals; D003530:Cyprinidae / Q000378:metabolism*; D003634:DDT / Q000032:analysis / Q000378:metabolism*; D004784:Environmental Monitoring; D011078:Polychlorinated Biphenyls / Q000032:analysis / Q000378:metabolism*; D045483:Rivers / Q000737:chemistry; D013030:Spain; D014874:Water Pollutants, Chemical / Q000032:analysis / Q000378:metabolism*
chemical_list: D014874:Water Pollutants, Chemical; D003634:DDT; D011078:Polychlorinated Biphenyls
keywords: DDTs; Freshwater fish; Iberian barbel; Organochlorine compounds; PCBs; Spain