Signal Words WARNING Warning"reflects an intermediate degree of relative toxicity All pesticides with an LDs0 of greater than 50 and less than 500 mg/kg must display this word on their label Pesticides in this category are classed as "moderately toxic” Mistretta USFS R-8 Signal Words WARNING “Warning” reflects an intermediate degree of relative toxicity All pesticides with an LD50 of greater than 50 and less than 500 mg/kg must display this word on their label Pesticides in this category are classed as “moderately toxic” Mistretta USFS R-8