title: Long-term monitoring of the health status of female perch (Perca fluviatilis) in the Baltic Sea shows decreased gonad weight and increased hepatic EROD activity.
abstract: Annual investigations of the health status of female perch (Perca fluviatilis) were performed during 8-13 years in order to detect long-term, large-scale changes in the Baltic Sea. These background data are also meant to be used as baselines in recipient investigations at various point sources in the Baltic Sea. Fish were sampled at three coastal sites in Sweden: two in the Baltic Proper (since 1988) and one in the Bothnian Bay (since 1993). In all, 19 biochemical, physiological and histopathological variables were measured. By reflecting central functions of life, such as red blood cell functions, immune defence, liver function, biotransformation processes, intermediary metabolism, ion balance, and reproduction, the selected variables give a good picture of the health status of the fish. The most important observations were strong trends towards decreased gonadosomatic index (relative gonad size) and increased hepatic EROD activity in female perch in the Baltic Proper. Most of the other variables varied little between the years. The reduced gonad size and the EROD induction indicate that factors in the environment, e.g. the occurrence of pollutants, affect important physiological functions, such as reproduction and biotransformation processes, in fish even in a reference area in the Baltic Proper. It is urgent to make further studies in order to identify which pollutant(s) or other possible cause(s) are responsible for the observed biological effects.
authors.affiliation: Department of Applied Environmental Science, ITM, Stockholm University, SE-106 91 Stockholm, Sweden. tomas.hansson@itm.su.se
authors.forename: Tomas
authors.initials: T
authors.lastname: Hansson
authors.forename: Eric
authors.initials: E
authors.lastname: Lindesjöö
authors.forename: Lars
authors.initials: L
authors.lastname: Förlin
authors.forename: Lennart
authors.initials: L
authors.lastname: Balk
authors.forename: Anders
authors.initials: A
authors.lastname: Bignert
authors.forename: Ake
authors.initials: A
authors.lastname: Larsson
mesh_terms: D000818:Animals; D001773:Blood Cells / Q000187:drug effects; D002712:Chlorides / Q000097:blood; D019363:Cytochrome P-450 CYP1A1 / Q000032:analysis / Q000187:drug effects*; D003625:Data Collection; D004781:Environmental Exposure; D004784:Environmental Monitoring; D005260:Female; D006066:Gonads / Q000187:drug effects* / Q000502:physiology; D008099:Liver / Q000187:drug effects / Q000201:enzymology*; D009792:Oceans and Seas; D010471:Perches / Q000502:physiology*; D013997:Time Factors; D014874:Water Pollutants, Chemical / Q000633:toxicity*
chemical_list: D002712:Chlorides; D014874:Water Pollutants, Chemical; D019363:Cytochrome P-450 CYP1A1