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Description
The Sterile Insect Technique (SIT) is based on the release of irradiated males to suppress insect populations through induced sterility. The success of this approach depends on the accurate delivery and verification of absorbed dose, ensuring effective sterilization while preserving insect quality and mating competitiveness. In this context, reliable dosimetry systems are essential for validating irradiation protocols and supporting operational SIT programs.
This study investigates gamma irradiation applied to Aedes aegypti males at different developmental stages, with particular emphasis on absorbed dose determination through alanine dosimetry. Irradiations were performed using a Cobalt-60 source, delivering doses up to 70 Gy to pupae and adult mosquitoes. Alanine dosimeters were used to estimate absorbed dose and assess dose distribution within the irradiation chamber. These dosimeters were measured using an Electron Paramagnetic Resonance (EPR) spectrometer model Magnettech ESR5000 (Bruker), operating in X-band.
The results showed a clear increase in sterility with dose, confirming the effectiveness of gamma radiation for SIT applications. Adult irradiation at 60 Gy resulted in sterility levels close to complete suppression, while maintaining higher survival and mating performance compared to irradiation at the pupal stage. These findings indicate that irradiation stage and dose selection are critical parameters that directly influence SIT efficiency.
The use of alanine dosimetry proved fundamental for confirming the absorbed dose and ensuring consistency in irradiation conditions. Its application strengthens the reliability and traceability of the sterilization process. This work contributes to the optimization of irradiation protocols and highlights the importance of robust dosimetric verification for the implementation and standardization of SIT programs targeting Aedes aegypti mosquitoes.