Formulation Dependent Degradation of Cadusafos: A Comparative Study under Thermal and Photolytic Conditions

The present paper discusses the degradation of the organophosphate pesticide cadusafos in terms of the active ingredient (a.i), Granules (GR), and Capsule Suspension (CS) formulations. The stability of these formulations in different environmental factors, such as accelerated storage, different temperatures (30 °C, 40 °C, and 50 °C), and in direct sunlight and UV radiation, was investigated, and the rate of degradation and half-lives were computed with the help of first-order kinetics. The CS formulation was the most stable to accelerated storage (54 ±2 °C for 14 days), with a loss of the active ingredient being 2.76% compared with 6.66% in the GR formulation. Thermal degradation tests revealed that the half-life of cadusafos decreased with increasing temperature, with the stability following this pattern: CS > GR > a.i., for example, the half-lives of CS, GR, and a.i., were 198 h, 177.69 h, and 169.02 h at 50 °C, respectively. The CS formulation had the lowest degradation with a half-life of 10.61 h under the sunlight, compared to GR and a.i., the half-lives were 8.24 h and 6.55 h, respectively. A similar pattern was recorded under UV radiation. Such findings reveal that the encapsulation technology on the CS formulation provides high levels of protection against thermal and photodegradation, which greatly increases the environmental stability of cadusafos. The study indicates the importance of the formulation type as a significant factor in the control of the environmental effectiveness of pesticides.