Twenty years ago, researchers wishing to identify contaminated areas in aquatic environments generally took water samples, and analysed them badly (as we have since discovered) for a few "pollutants" which were of topical note at the time (and which could be quantified by the methods then available). Today, the use of aquatic organisms as biomonitors in preference to water analysis has become commonplace, and many national and interna tional programmes exist around the world involving such studies. We believe that this trend will continue, and have complete faith in the methodology (when it...

Twenty years ago, researchers wishing to identify contaminated areas in aquatic environments generally took water samples, and analysed them badly (as we have since discovered) for a few "pollutants" which were of topical note at the time (and which could be quantified by the methods then available). Today, the use of aquatic organisms as biomonitors in preference to water analysis has become commonplace, and many national and interna tional programmes exist around the world involving such studies. We believe that this trend will continue, and have complete faith in the methodology (when it...