Sentence:  The rate of the ichthyotoxic effect on immersed minnows within the temperature range of 10–30°C increases directly with the temperature (from 3 hours to 30 minutes), but the final titer of the <WSD>ichthyotoxin</WSD> is identical at both high and low temperatures. 
Meaning of the word marked with <WSD> tags:  Any chemical compound that is toxic to fish.