Microbiotesting: an expanding field in aquatic toxicology.

In terms of bioanalytical development and application, environmental evolution in this century can be perceived as having gone from the "dark ages" (time period preceding the 1960s and essentially characterized by nonuse of bioassays), to the "beginning of enlightenment" (use of fish bioassays during the 1960s as screening tools for effluents and specific chemicals), to the "regulatory 1970s," when newly created environment departments in developed countries began to sanction bioassays for regulatory purposes, to the "ecotoxicological 1980s," when suites of (micro) bioassays were incorporated in various hazard assessment schemes, right up to the present "microbiotesting 1990s," when an unprecedented upsurge in development and demand for cost-effective multilevel small-scale assays is manifest. This paper offers the view that microscale aquatic toxicology is a rapidly expanding field of ecotoxicology involving numerous bioanalytical techniques developed and applied at various levels of biological organization. This is demonstrated by recalling some of the major highlights that triggered the way for increased use of microbiotesting over the past decades. It is expected that the field of microbiotesting will sustain continuing growth in the future and contribute significant diagnostic power to environmental programs requiring ecotoxicology.