Efficacy of mosquito control insecticides and their impact on indoor air quality: A controlled chamber study in Bangladesh

Background Dengue and other mosquito-borne diseases remain major public health concerns in tropical regions such as Bangladesh. Although household mosquito control products are widely used, their combined insecticidal efficacy and impact on indoor air quality remain insufficiently characterized. This study aimed to provide an integrated assessment of both efficacy and emission profiles under controlled ventilation conditions. Methods Eighteen household mosquito control products (13 coils, 3 aerosols, and 2 vaporizers) were evaluated against laboratory-reared female Aedes aegypti in controlled glass chambers under well-ventilated and poorly ventilated conditions. Mortality dynamics were analyzed using Kaplan–Meier survival curves and hazard rates. Indoor air pollutants (PM₂.₅, PM₁₀, CO, SO₂, NO₂, and TVOCs) were measured using Aeroqual S500 monitors. Statistical analyses included ANOVA, Tukey’s HSD, and Wilcoxon signed-rank tests. Results Mosquito coils showed moderate efficacy, with mortality of 56–72% under ventilated conditions and 70–88% under poorly ventilated conditions, remaining below World Health Organization (WHO) susceptibility thresholds. Aerosol sprays produced rapid knockdown (72–78% mortality within 30 min), whereas vaporizers showed slower but sustained effects. Emission profiles differed across products. Under poor ventilation, coils generated substantially higher concentrations of CO (up to ∼42.6 mg/m³), PM₂.₅, SO₂, and TVOCs, frequently exceeding guideline values. Aerosols and vaporizers produced lower particulate emissions but still contributed to chemical exposure. Conclusion Household mosquito control products present clear efficacy–exposure trade-offs. Combustion-based coils offer limited vector control while substantially degrading indoor air quality, particularly in poorly ventilated settings. These findings highlight the need for safer formulations, improved ventilation, and integrated vector management strategies.