A Portable Dual Mass Spectrometry Strategy for On-Site Monitoring of Accumulation Effects and Exposure Risks of Insecticides during Chikungunya Epidemics

Intensive insecticide use has been repeatedly employed to prevent the spread of mosquito-borne Chikungunya fever, but poses potential exposure risks to ecosystems and environments. Herein, we developed a dual mass spectrometric (MS) strategy for on-site monitoring of typical insecticides in different environmental media and for assessing associated exposure risks during the Chikungunya epidemics. The dual MS strategy demonstrated good analytical performance for on-site analysis, including sensitivity (at parts per billion level), reproducibility (<20%, n = 7), and analytical speed (within 10 min). It was found that the main active compounds, such as permethrin and allethrin, persist in water and soil, whereas volatile auxiliaries such as toluene and isooctyl alcohol rapidly volatilize into ambient air immediately after spraying. Particularly, sawtooth-shaped accumulation effects of non-volatile insecticides were found after repeated applications. Furthermore, a successive five-day monitoring revealed that health exposure risks would be significantly increased due to the cumulative effects of repeated insecticide spraying. Overall, this study not only provides a promising strategy for the on-site monitoring of insecticides but also offers valuable insights into their cumulative effects and associated exposure risks across different environmental media.