Abstract
A new optical bio-assay using brine shrimp larvae (Anemia salina L.) has been successfully applied for monitoring the presence of highly toxic trichothecenes. The motility of the swimming animals was determined instead of their lethality. This permits more objective and precise results. The inhibition of the motility can be seen earlier, than the death of animals in toxicity tests. The relationship between time and dose is indicated for two different concentrations. This test can also be applied in the control of other harmful compounds.