4-Chlorophenoxyacetic acid

Synonyms

(4-Chlorophenoxy)acetic acid; 4-CP; 4-CPA; 4CPA; Acetic acid, (4-chlorophenoxy)-; Acetic acid, (p-chlorophenoxy)-; BI 12; CPA; Kyselina 4-chlorfenoxyoctova [Czech]; Marks 4-CPA; PCPA; Parachlorophenoxyacetic acid; Sure-Set; Tomato Fix; Tomato Fix concentrate; Tomato hold; Tomatotone; p-Chlorophenoxyacetic acid; [ChemIDplus]

Category

Herbicides, Chlorophenoxy

Description

Odorless solid; [HSDB] White or off-white powder; [MSDSonline]

Sources/Uses

Used as a specialized plant growth regulator to improve fruit set in tomatoes, berries, and other fruit; May also be used to replace pollination; [HSDB] Used to regulate root growth of mung beans in seed germination; [Reference #1]

Comments

Caused severe eye irritation but no skin irritation in studies with rabbits; Effects in high-dose 13 week feeding studies with rats include decrease in weight gain and "increased incidence of slight hepatic lymphohistiocytic infiltrates and slight individual hepatocellular necrosis in males" (NOEL = 2000 ppm, LOEL = 8000 ppm); [HSDB] Chlorophenoxy herbicides are possibly carcinogenic to humans (Group 2B); [IARC] See "2,4D."

Registration cancelled for use on tomatoes in 1994; [Reference #1]

Reference Link #1

Biomedical References

0.000318 mm Hg

LC50 (rat) > 5,250 mg/m3

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

Processes

Industrial Processes with risk of exposure:

• Farming (Pesticides)