Fish physiology and metal pollution: results and experiences from laboratory and field studies.

Physiological methods, previously used as health indicators in laboratory investigations on fish exposed to toxicants, have been applied to feral fish living in metal-polluted waters. A background to the use of a physiological approach for detecting early-arising effects of toxic chemicals on fish is given, together with a description of the clinical parameters used and their physiological relevance. The results and experiences from the field application show that certain clinical methods may be very useful in detecting and diagnosing sublethal disturbances in natural fish populations in polluted areas. Furthermore, the results indicate a good agreement between metal-induced physiological effects detected in fish exposed under natural field conditions and those found in laboratory experiments.