(+)-R-2-(2,4-Dichlorphenoxy)-propionsäure

Danger

H302: Harmful if swallowed [Warning Acute toxicity, oral]；H315: Causes skin irritation [Warning Skin corrosion/irritation]；H317: May cause an allergic skin reaction [Warning Sensitization, Skin]；H318: Causes serious eye damage [Danger Serious eye damage/eye irritation]

P261, P264, P264+P265, P270, P272, P280, P301+P317, P302+P352, P305+P354+P338, P317, P321, P330, P332+P317, P333+P317, P362+P364, and P501 (click each P-code to see the statement)

Danger

Commission Regulation No 844/2012

2,4-DP-p + salt & ester is listed in the dataset of EPA Human Health Benchmarks for Pesticides under the Safe Drinking Water Act (40 eCFR 141)

2006/74/EC, Reg. (EU) 2019/168, Reg. (EU) 2018/524, Reg. (EU) 2020/421, Reg. (EU) 2021/566, Reg. (EU) 2022/378, Reg. (EU) 2023/689, Reg. (EU) 2025/99, Reg. (EU) No 1166/2013, Reg. (EU) No 540/2011, Reg. (EU) No 878/2014

Status: Active Update: 10-11-2008 https://echa.europa.eu/registration-dossier/-/registered-dossier/9307

Dichlorprop-p: Does not have an individual approval but may be used under an appropriate group standard

Risk of serious damage to eyes; A 6-year study of workers handling phenoxy herbicides did not find any adverse effects; Workers had no abnormalities of hemoglobin, liver function tests, or kidney function tests; [European Food Safety Authority (EFSA): Active Substances in Plant Protection Products] See Dichlorprop.

Acute Tox. 4 (100%)；Skin Irrit. 2 (100%)；Skin Sens. 1 (100%)；Eye Dam. 1 (100%)；Aquatic Acute 1 (50%)；Aquatic Chronic 2 (50%)

Acute Tox. 4 (100%)；Skin Irrit. 2 (100%)；Skin Sens. 1 (100%)；Eye Dam. 1 (100%)

Skin irritation - category 2；Eye damage - category 1；Skin sensitisation - category 1；Acute toxicity (ingestion) - category 4

Acute Tox. 4 *；Skin Irrit. 2；Eye Dam. 1；Skin Sens. 1

It is considered to be a severe eye irritant. There has been concern that chlorophenoxy herbicides including dichlorprop may cause cancer, and in 1987 the International Agency for Research on Cancer (IARC) ranked this class of compounds as group 2B "possibly carcinogenic to humans". The EPA classifies the R-isomer as “Not Likely to be Carcinogenic to Humans.”(L369) Exposure to large amounts of CDDs causes chloracne, a severe skin disease with acne-like lesions that occur mainly on the face and upper body. CDDs may also cause liver damage and induce long-term alterations in glucose metabolism and subtle changes in hormonal levels. In addition, studies have shown that CDDs may disrupt the endocrine system and weaken the immune system, as well as cause reproductive damage and birth defects, central and peripheral nervous system pathology, thyroid disorders, endometriosis, and diabetes. 2,3,7,8-Tetrachlorodibenzo-p-dioxin is also a known human carcinogen. (L177, L178)

CDDs cause their toxic effects by binding to the aryl hydrocarbon receptor and subsequently altering the trascription of certain genes. The affinity for the Ah receptor depends on the structure of the specific CDD. The change in gene expression may result from the direct interaction of the Ah receptor and its heterodimer-forming partner, the aryl hydrocarbon receptor nuclear translocator, with gene regulatory elements or the initiation of a phosphorylation/dephosphorylation cascade that subsequently activates other transcription factors. The affected genes include several oncogenes, growth factors, receptors, hormones, and drug-metabolizing enzymes. The change in transcription/translation of these genes is believed to be the cause of most of the toxic effects of CDDs. This includes 2,3,7,8-tetrachlorodibenzo-p-dioxin's carcinogenicity is thought to be the result of its ability to alter the capacity of both exogenous and endogenous substances to damage the DNA by inducing CYP1A1- and CYP1A2-dependent drug-metabolizing enzymes. (L177)

Commission Regulation No 844/2012

2,4-DP-p + salt & ester is listed in the dataset of EPA Human Health Benchmarks for Pesticides under the Safe Drinking Water Act (40 eCFR 141)

2006/74/EC, Reg. (EU) 2019/168, Reg. (EU) 2018/524, Reg. (EU) 2020/421, Reg. (EU) 2021/566, Reg. (EU) 2022/378, Reg. (EU) 2023/689, Reg. (EU) 2025/99, Reg. (EU) No 1166/2013, Reg. (EU) No 540/2011, Reg. (EU) No 878/2014

Status: Active Update: 10-11-2008 https://echa.europa.eu/registration-dossier/-/registered-dossier/9307

Dichlorprop-p: Does not have an individual approval but may be used under an appropriate group standard

CDDs are absorbed through oral, inhalation, and dermal routes of exposure. CDDs are carried in the plasma by serum lipids and lipoproteins, distributing mainly to the liver and adipose tissue. CDDs are very slowly metabolized by the microsomal monooxygenase system to polar metabolites that can undergo conjugation with glucuronic acid and glutathione. They may increase the rate of their own metabolism by inducing CDDs induce both phase I and phase II enzymes. The major routes of excretion of CDDs are the bile and the feces, though smaller amounts are excreted in the urine and via lactation. (L177)

Used as a post-emergence herbicide against broadleaf weeds and brush in ornamental lawns, recreational turf, sod farms, roadsides, industrial sites, rights-of-way, and forests; [Reference #1]

Dioxins occur as by-products from the manufacture of organochlorides, the bleaching of paper, chlorination by waste and drinking water treatment plants, municipal solid waste and industrial incinerators, and natural sources such as volcanoes and forest fires. (L177, L178)

Herbicides, Plant growth regulators

Environmental transformation -> Pesticides (parent, predecessor)