Evaluation of the toxicity of a new series of α-aminophosphonate derivatives in a target (Ephestia Kuehniella) and non-target (Lumbricus rubellus) population

A new series of ᾳ-aminophosphonate derivatives was evaluated for their toxicity in a target (Ephestia kuehniella) and non-target (Lumbricus rubellus) population, after was synthetized by an immersion ultrasound-assisted method. It is a green chemical approach that focuses on designing industrial products and processes with minimal impact on operator, environmental, and consumer health.

Firstly, we tested the insecticidal activity of five molecules (BR1, BR2, BR3, BR4, and BR5) in Ephestia larvae compared to Dursban using fumigation, contact, and repulsion. Furthermore, we determined their toxicity in earthworms by measuring mortality rate (TM%), weight, glutathione (GSH), acetylcholine esterase activity (AchE), and glutathione-s-transferase (GST).

The results show that the BR1, BR2, and BR3 molecules have strong insecticidal activity (TM > 50%) by fumigation, moderate to strong activity by contact, and low to very low activity by repulsion. We observed no mortality in worms treated with these derivatives, and weight decreased significantly (P < 0.01) compared to controls. Monitoring of stress biomarker variations revealed inhibition of AchE in Lumbricus ranging from 21 to 40% for all treatments when compared to the marketed pesticide (66%), an increase in GSH levels, and induction of non-significant GST activity, indicating moderate oxidative stress.

All of these findings emphasize the insecticidal activity of these molecules on the target population (Ephestia kuehniella) while ignoring their repellent mode and the significance of the fraction inserted to reduce the toxic impact of these compounds on non-population targets (Lumbricus rubellus).