Signal words on labels give an estimate of pesticide toxicity

Information taken from the UGA publication Insecticide Basics for the Pest Management Professionalby Dan Suiter, UGA Department of Entomology, and Michael Scharf, Purdue University Department of EntomologyThe signal word found on every product’s label is based on test results from various oral, dermal, and inhalation toxicity tests, as well skin and eye corrosion assays in some cases. Signal words are placed on labels to convey a level of care that should be taken (especially personal protection) when handling and using a product—i.e., from purchase to disposal of the empty container (Table 1).

Table 1. Toxicological parameters related to signal words found on EPA-registered pesticide product labels.

Signal Word on Label Toxicity Category Acute-Oral LD50 for Rats Amount Needed to Kill an Average Sized Adult Notes
Danger-Poison Highly Toxic 50 or less Taste to a teaspoon Skull and Crossbones; Keep out of Reach of Children
Warning Moderately Toxic 50-500 One to six teaspoons Keep out of Reach of Children
Caution Slightly Toxic 500-5,000 One ounce to a pint Keep out of Reach of Children
Caution Relatively Non-Toxic >5,000 Greater than a pint Keep out of Reach of Children

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