Electrophoretic determination of estrogen-induced protein in fish exposed to synthetic and naturally occurring chemicals

Abstract In a first step we investigated whether Leuciscus idus , a fish routinely used to assess the quality of surface water in Germany, is suitable to indicate the presence of endocrine-disrupting chemicals. An electrophoretic method was used to determine estrogen-induced protein in fish serum (presumed vitellogenin). This method was tested by exposing juvenile L. idus to 17α-ethinylestradiol, 17β-estradiol and estrone. Nominal concentrations of the steroid were compared with concentrations determined analytically by using GC/MS techniques. Under flow-through conditions, 7 days of exposure to 6 ng/l EE 2 significantly induced serum vitellogenin in juvenile L. idus . In juvenile rainbow trout ( Oncorhynchus mykiss ) 4 ng/l EE 2 induced significantly elevated levels of serum vitellogenin. In Danio rerio oral application of 40 μg 4-nonylphenol/fish per day during a 3-week exposure period caused a major increase of serum vitellogenin. Physiological protein induction could also be measured in Abramis brama , Cyprinus carpio , Oncorhynchus mykiss , Perca fluviatilis , Rutilus rutilus obtained from natural habitats and in Rhodeus sericeus . The minimum amount of blood required for electrophoretic analysis was 1 μl which should allow monitoring of small sized fish species as well as juvenile fish.