2,4,5-T

Synonyms

(2,4,5-Trichloor-fenoxy)-azijnzuur [Dutch]; (2,4,5-Trichlor-phenoxy)-essigsaeure [German]; 2,4,5-Trichlorophenoxyacetic acid; Acide 2,4,5-trichloro phenoxyacetique [French]; Acido (2,4,5-tricloro-fenossi)-acetico [Italian]; Arbokan; BCF-Bushkiller; Brush Killer; Brush RHAP; Brush-off 445 low volatile brush killer; Brushtox; Cido (2,4,5-tricloro-fenossi)-acetico [Italian]; Crossbow; Debroussaillant concentre; Debroussaillant super concentre; Decamine 4T; Ded-Weed; Ded-weed brush killer; Ded-weed lv-6 brush kil and t-5 brush kil; Envert-T; Estercide t-2 and t-245; Farmco fence rider; Fence rider; Forron; Forst U 46; Fortex; Fruitone A; Inverton 245; Kwas 2,4,5-trojchlorofenoksyoctowy [Polish]; Line rider; Lo-vol; Phortox; Reddon; Reddox; Spontox; Super D Weedone; T-Nox; Tippon; Tippontormona; Trioxon; VEON; Veon 245; Verton 2T; Visko Rhap; Visko rhap low volatile ester; [ChemIDplus] 2,4,5T

Category

Herbicides, Chlorophenoxy

Description

Colorless to tan, odorless, crystalline solid. [herbicide]; [NIOSH]

Sources/Uses

Not produced in the U.S since 1983; [ACGIH]

Comments

2,4,5-T is toxic to the liver in acute animal studies. Epidemiology studies found no evidence that 2,4,5-T is teratogenic to exposed workers. [ACGIH] There is limited positive evidence that 2,4,5-T causes birth defects in animals. There is strong negative data that it causes skeletal defects in humans. [ATSDR Case Studies #29] "Overall, it appears that the chlorophenoxy herbicides have led to little or no hepatic injury. Where sufficient occupational exposure seems to have led to hepatic abnormalities (e.g., toxic porphyria), the presumed chemical culprit has been the contaminating TCDD, rather than the herbicide per se." [Zimmerman, p. 415] In poisoning cases by ingestion of chlorophenoxy compounds, elevated liver enzymes and rhabdomyolysis with secondary renal failure have been reported; [HSDB]

All uses in the U.S. canceled in 1985; [EPA Pesticides, p. 95]

Biomedical References

Insufficient data

Yes

10 mg/m3

10 mg/m3

2 mg/m3, inhalable fraction

250 mg/m3

Excerpts from Documentation for IDLHs

Basis for original (SCP) IDLH: According to ACGIH [1971], "the toxicity of this compound appears to be similar to the somewhat better known 2,4­D. According to Rowe and Hymas [1954], the oral LD50 values fall in a range of 300 to 1,000 mg/kg for rats, mice, guinea pigs, and rabbits. Chronic exposure is not necessarily more hazardous. Drill and Hiratzka [1953] found that there were no deaths among dogs treated with 2, 5, or 10 mg/kg/day of 2,4,5­T (5 days/week for 13 weeks); some deaths occurred at 20 mg/kg/day. There are no reports of illness from occupational exposure. It appears that the TLV of 10 mg/m3 is justified on the basis of extrapolation from animal feeding studies and extensive use experience." Based on the toxicological data cited above, 2,4,5­T is a relatively nontoxic compound. Because data on acute inhalation toxicology are not available for this substance and to be consistent with the IDLHs selected for similar, relatively nontoxic compounds, 5,000 mg/m3 (i.e., 500 times the OSHA PEL of 10 mg/m3) has been chosen as the concentration above which only the "most protective" respirators are permitted. . . . Basis for revised IDLH: No inhalation toxicity data are available on which to base an IDLH for 2,4,5­T. Therefore, the revised IDLH for 2,4,5­T is 250 mg/m3 based on acute oral toxicity data in animals [AAPCO 1966; Bailey and White 1965; Grant 1979; Senczuk and Pogorzelska 1980]. This may be a conservative value due to the lack of relevant acute inhalation toxicity data for workers.

Explanatory Notes

VP at 25 deg C: negligible; [ICSC] VP from HSDB;

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

Yes

Not Classifiable

Other Information

No other related information on this agent was found.