Pesticides with high LD50 values (10+) are more toxic.

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Multiple Choice

Pesticides with high LD50 values (10+) are more toxic.

Toxicity in the acute sense is inversely related to LD50. LD50 is the dose that kills 50% of exposed animals, usually expressed per kilogram of body weight. A smaller LD50 means a small amount is enough to be lethal, so the substance is highly toxic. A larger LD50 means you need a bigger dose to produce the same effect, so it is less toxic. Therefore, pesticides with high LD50 values are less toxic, not more. The idea holds across exposure routes (oral, dermal, inhalation), though LD50 numbers differ by route; the general relationship—higher LD50 equals lower acute toxicity—still applies.

Toxicity in the acute sense is inversely related to LD50. LD50 is the dose that kills 50% of exposed animals, usually expressed per kilogram of body weight. A smaller LD50 means a small amount is enough to be lethal, so the substance is highly toxic. A larger LD50 means you need a bigger dose to produce the same effect, so it is less toxic. Therefore, pesticides with high LD50 values are less toxic, not more. The idea holds across exposure routes (oral, dermal, inhalation), though LD50 numbers differ by route; the general relationship—higher LD50 equals lower acute toxicity—still applies.

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