Table 1.
Comparison of the neurotoxicity of fipronil and its desulfinyl and detrifluoromethylsulfinyl photoproducts
| Compound | Assay
and species
|
||||
|---|---|---|---|---|---|
| LD50,
mg/kg
| |||||
| Housefly | Housefly (+ PB) | Mouse | Receptor IC50,
nM
|
||
| Housefly | Mouse | ||||
| Fipronil | 0.13 | 0.020 | 41 | 6.3 ± 1.3 | 1010 ± 20 |
| Desulfinyl | 0.058 | 0.045 | 23 | 5.4 ± 1.0 | 97 ± 4 |
| Detrifluoromethylsulfinyl | >150 | 20 | >100 | 235 ± 18 | >10,000 |
The LD50 values at 24 h are reproducible within 2.0-fold for houseflies and 1.3-fold for mice in repeated experiments. Twelve mice and several hundred houseflies were used for each determination. The receptor IC50 values are given as mean ± SEM (n = 3). PB, piperonyl butoxide.