Elimination of aziridine residues from chemosterilised mosquitoes

Abstract

CRITICISM^1–4 of the use of the alkylating agent thiotepa (triethylene thiophosphoramide) to sterilise mosquitoes, as part of an eradication programme in India, focused on its toxicity and the possibility that it or its breakdown products would harm other animal components of the food chain. For example, a Canadian team found reduced fertility in spiders fed on mosquitoes sterilised with thiotepa⁵. Some means was needed to ensure that no aziridine residues—breakdown products of thiotepa—remain in the insects after release into the environment. We have now achieved this, essentially by dipping the chemosterilised insects into acid and then alkaline solutions.