Table 1.

Qualitative classification of toxic signs of intoxication presented by guinea pigs challenged with lxLD50 soman

Score	Signs of toxicity	Classification of toxicity
0	No abnormal gross behavior	Mild
1	Facial twitches, pawing at whiskers and mouth, chewing
2	Head tremor and/or nodding, short periods of immobility	Moderate
3	Forelimb clonus
4	Rearing with no loss of balance, strong grinding, gnashing or bruxism	Severe
5	Rearing with loss of balance, frank convulsions

The severity of the soman-induced acute toxicity was classified as described in Aracava et al. (2009).