Acetochlor

Manufacture

Acetochlor is manufactured in two steps from 2-ethyl-6-methylaniline. A reaction with chloroacetyl chloride gives an anilide which is treated with chloromethyl ethyl ether and sodium hydroxide to form the herbicide. :[[File:Industrial synthesis of acetochlor.svg|550px]]

Uses

In the United States, acetochlor was registered by the EPA as a direct substitute for many herbicides of known concern. The EPA imposed several restrictions and conditions on the use of acetochlor.

It is approved for pre-emergence application or for pre-planting application with soil incorporation, in corn. (maize) at 5 litres / hectare (1835g / hectare of a.i.) It is the main active ingredient in Acenit, Keystone, Guardian, Harness, Relay, Sacemid, Surpass, Top-Hand, Trophy and Winner.

It is used to control weeds in corn, and is particularly useful as a replacement for atrazine in the case of some important weeds.

Safety

Acetochlor has been classified as a probable human carcinogen. Acetochlor, as alachlor, can cause nasal turbinate tumors via the generation of a common tissue reactive metabolite that leads to cytotoxicity and regenerative proliferation in the nasal epithelium.

It is a thyroid disruptor.{{Cite journal

Human health effects from acetochlor at low environmental doses or at biomonitored levels from low environmental exposures are unknown. A case of poisoning with extremely swollen genitals as a symptom was reported after contact.

Ecologic effects

In the United States, acetochlor is the third most frequently detected herbicide in natural waters.

Acetochlor can accelerate metamorphosis in amphibians. It can also affect the development of fish.

References

References

1. [https://pmep.cce.cornell.edu/profiles/extoxnet/24d-captan/acetochlor-ext.html Cornell University Extension Toxicology Network Pesticide Information Profile on Acetochlor]
2. (31 December 1996). "Pesticide Synthesis Handbook". William Andrew.
3. "Acetochlor". EPA.
4. "e-phy". agriculture.gouv.fr.
5. (2006-03-29). "Cumulative Risk Assessment for the Chloroacetanilides". EPA.
6. (11 February 2010). "National Report on Human Exposure to Environmental Chemicals". CDC.
7. (2019). "Acetochlor poisoning presenting as acute genital edema: A case report". Urology Case Reports.
8. (2008). "A multiphasic characterization of the impact of the herbicide acetochlor on freshwater bacterial communities.". The ISME Journal.
9. (2009). "Effects of exposure to acetochlor on the expression of thyroid hormone related genes in larval and adult rare minnow (Gobiocypris rarus)". Aquatic Toxicology.