Residual activity of C14 solutions and formulates on Ae. aegypti larvae.

Mortality was assessed after 12 h irradiation (1.0–4.0 mW/cm2).*time elapsed between the preparation of the trays and the introduction of 3rd–4th instar larvae (n = 100 larvae; 3 replicates). During this period, trays were incubated in the climatic chamber (12 h photoperiod; 28±2°C; >90% RH). Numbers in parentheses indicate standard deviations.†trays contained 6 mg of untreated larval food in C14 porphyrin solutions at the indicated concentration.‡trays contained 6 mg of the indicated formulation in spring water.§one surviving larva was found in the tray. Such larvae were negative for C14 fluorescence at the microscope, therefore they hadn't fed during the experiment.