Amitrole

Synonyms

Aminotriazole; 3-Aminotriazole; 2-Amino-1,3,4-triazole; 3-Amino-1,2,4-triazole; Amerol; Amitrol; Amizine; Amizol; Azolan; Azole; Cytrol; Diurol; Weedazol [EXTOXNET]

Category

Herbicides, Other

Description

Colorless to white, crystalline powder. [herbicide] [Note: Odorless when pure.]

Sources/Uses

Used control grasses, broadleafs, poison ivy, and aquatic weeds. [EXTOXNET]

Comments

In the triazole class of herbicides, the known toxicity of amitrole is limited to slight irritant effects. [EPA Pesticides, p. 121] Classified as "slightly toxic," it may be used only by certified applicators. [EXTOXNET] A weed control worker with allergic contact dermatitis was reported; [Kanerva, p. 783] Aminotriazole "may be hepatotoxic on ingestion." [Zimmerman, p. 393] The following herbicides have an oral LD50 of >1 gm/kg and have little or no acute toxicity in humans: Alachlor, Amitrole, Ammonium sulfamate, Atrazine, Dalapon, Dicamba, Glyphosphate, Monuron, Oryzalin, Picloram, Propanil, Simazine, etc. [LaDou, p. 613] TLV basis: thyroid effects; [ACGIH]

Use on food crops was canceled by the EPA in 1971; [EXTOXNET]

Reference Link #1

Biomedical References

Insufficient data

0.2 mg/m3

0.2 mg/m3, inhalable fraction

4.4E-07 mm Hg

LC50 >500 mg/m3

Explanatory Notes

VP from HSDB;

Reference Link #2

Yes

Hepatoxic (a) from occupational exposure (secondary effect) or (b) in animal studies or in humans after ingestion

Yes

Not classifiable

Anticipated human carcinogen

Confirmed Animal

Diseases

Occupational diseases associated with exposure to this agent:

• Contact dermatitis, allergic