Description

Dicamba is an herbicide used to control broadleaf weeds, brush and vines on lawns, grain crops, grasslands and non-crop areas, such as roadways. Dicamba is contained in several pre-mixed herbicide products that contain other herbicides, such as 2,4-D or mecoprop.

Health Effects

Immediate Health Effects

If SWALLOWED, 3,6-dichloro-2-methoxybenzoic acid is Moderately Toxic
If ABSORBED THROUGH SKIN, 3,6-dichloro-2-methoxybenzoic acid is Moderately Toxic
If INHALED (SNIFFED OR BREATHED IN), 3,6-dichloro-2-methoxybenzoic acid is Slightly Toxic

Longterm or Delayed Health Effects

This chemical is considered an Unclassifiable Carcinogen by the World Health Organization, the U.S. Environmental Protection Agency, or another agency.

Other

Skin and eye irritation, such as rash, redness or burning feeling, eye pain, blurred vision. Can cause severe and permanent damage to eyes.
Lung congestion, poor digestion, inflamed kidneys, engorged livers.
Muscle cramping and weakness, loss of voice, dizziness, rashes, swollen neck glands, nausea, vomiting, weight loss.
Neurologic effects, such as agitation, or excitability or depression.
May affect the liver.
Can potentially damage cell DNA.
Can inhibit a nervous system enzyme preventing smooth nerve cell communication.
One study showed increased risk of non-Hodgkin’s lymphoma.
May cause birth defects.

How Exposures Occur

Inhalation

Children may be exposed to dicamba during or after application if they are close to treated areas. Dicamba evaporates and becomes air-borne quickly, especially when temperatures are high. The resulting vapors can drift up to 5 or 10 miles under certain conditions.

Skin Contact

Children may come into contact with dicamba on treated sports fields and lawns. Dicamba is irritating to the skin and eyes.

Children may also pass dicamba from their hands to their eyes by touching their eyes after being in a treated area.

Drinking Water

Dicamba has been found in the drinking water supplies of several states including Ohio, Pennsylvania, Louisiana and Washington.

Accidental Ingestion

Accidental poisoning is a risk on farms or in homes where dicamba is stored within reach of children. Dicamba should be stored out of reach of children and in its original container.

Significant Statistics

Of the 5.6 million pounds used annually in the United States, 5 million pounds is used on corn.

Cox, Caroline. “Dicamba,” Journal of Pesticide Reform. Vol 14, No. 1 (Spring 1994) http://www.pesticide.org/dicamba.pdf.

Leaf spot disease, which affects blue grass, grows faster and produces more spores with dicamba treatment than without.

Cox, Caroline. “Dicamba,” Journal of Pesticide Reform. Vol 14, No. 1 (Spring 1994) http://www.pesticide.org/dicamba.pdf.

Dicamba works by mimicking a natural plant hormone causing abnormal growth that leads to plant death.

Dicamba. US Department of Agriculture. February 1999. http://www.fs.fed.us/r6/nr/fid/pubsweb/dicamba_99.pdf.

Dicamba is the seventh most commonly used conventional pesticide in the home and garden market.

Reregistration Eligibility Decision for Dicamba and Associated Salts. EPA. June 8, 2006.

http://www.regulations.gov/search/Regs/home.html#documentDetail?D=EPA-HQ-OPP-2005-0479-0026.

Solutions

How to detect 3,6-dichloro-2-methoxybenzoic acid

Read labels on all home and garden pesticides. You can also find out if dicamba is an ingredient in your lawn products on the Pesticide Action Network Pesticide Database. Or, search for dicamba in the National Library of Medicine’s Household Products Database to find a list of brands that contain it.
Dicamba is not regulated by the Safe Drinking Water Act, and public water supplies are not required to test for it. However, if you live in an agricultural area, especially where corn is grown, you may wish to have your water tested by state certified drinking water laboratories.

How to minimize exposure to 3,6-dichloro-2-methoxybenzoic acid

Avoid the use of pesticides whenever possible, especially near children. Any pesticides in your home should be tightly closed and kept out of the reach of children.
Contact your local sanitation department or hazardous waste disposal program to find out how to dispose of pesticides properly. Earth’s 911 lists hazardous waste disposal sites by zip code.

Alternatives

Adopt Integrated Pest Management practices instead of resorting to herbicides for weed removal. Remove garden weeds by hand; mulch the soil around garden plants to prevent weeds from sprouting. Diversify landscaping to reduce turf grass. See also How to Kill Weeds Without Herbicides.
Maintaining a healthy lawn is your best defense against weedy invaders. For more information about how to accomplish this, consult the resources below.
Buy certified organic foods, which are grown without synthetic pesticides, when you can. See 10 Foods to Buy Organic .

Otherwise, wash fruits and vegetables well and peel them.
If testing of your water reveals high levels of 2,4-D, you can filter your tap water.
Use a doormat to wipe feet or take shoes off at the door to keep pesticides and other pollutants from being tracked indoors.