Assessment of methods used to determine the safety of the topical insect repellent N,N-diethyl-m-toluamide (DEET)

Table 1 Results of toxicity testing of DEET on animals reported to the USEPA[11]

Test type	Animal	Outcome
Acute oral toxicity	Rat	Oral LD₅₀ = 2170–3664 mg/kg
		Toxicity category III: Slightly toxic and slightly irritating
Acute dermal toxicity	Rabbit	Dermal LD₅₀ = 4280 mg/kg
		Toxicity category III: Slightly toxic and slightly irritating
Acute inhalation toxicity	Rat	Inhalation LD50 = 5.95 mg/kg
		Toxicity category IV: Practically non-toxic and not an irritant
Subchronic (90 day) oral toxicity	Rat	Renal effects found in exposed male rats of two of three strains tested so no NOEL established.
Subchronic (90 day) oral toxicity	Hamster	NOEL: 61 mg/kg/day
		LEL: 305 mg/kg/day
Subchronic (90 day) dermal toxicity	Rat	Renal lesions in all male rats treated so no NOEL established
Subchronic (90 day) dermal toxicity	Micropigs	NOEL: 1000 mg/kg/day
Chronic (2 year) toxicity	Rats and dogs	NOEL: 100 mg/kg/day
		LEL: 400 mg/kg/day
		No carcinogenic effects
Chronic (78 weeks) toxicity	Mice	NOEL: 500 mg/kg/day
		LEL: 1000 mg/kg/day
		No carcinogenic effects
Reproductive toxicity	Rats	NOEL: 250 mg/kg/day (highest dose tested)
Developmental and maternal toxicity	Rats	NOEL: 250 mg/kg/day
		LEL: 750 mg/kg/day
Developmental toxicity	Rabbits	NOEL: 325 mg/kg/day (Highest dose tested)

ISSN: 1756-3305