My interest is in linking ecological stoichiometry with ecotoxicology. Initially, I have focused on how food quality affects acute toxicity in aquatic organisms. My collaborators at the University of Notre Dame and Trent University and I have shown that some toxins (iodine, cobalt, fluoxetine in particular) are stoichiometrically explicit, meaning the effects on organisms vary based on the quality of food the organism is getting. Other toxins do not appear to be stoichiometrically explicit (bendiocarb, triclosan, methanol) although it is obviously harder to prove.
The implications of stoichiometrically explicit toxins are presently unknown, but one can imagine a situation where the concentration of a toxin allowed by law is harmless when organisms are fed high-quality food, but detrimental when they are given poor quality food. Obviously, in nature species are often faced with food shortages or poor food quality, thus the actual effect of toxins may be much greater than the estimated effects. Evaluating the risk a chemical poses to an ecosystem therefore requires a more context specific approach. Are the receiving ecosystems frequently nutrient stressed? Are times of pollutant release going to coincide with occasions when ecosystems are nutrient stressed? I’m not sure whether regulatory agencies are equipped to permit in this way.
This kind of work is obviously just a first crack at the idea, and in many ways a very basic approach. Without this kind of base data, however, addressing more interesting questions becomes difficult. I believe that toxistoichiometry has the potential to provide a new axis of understanding for ecotoxicology.