Weed killers, also known as herbicides, make life easier for farmers, gardeners and homeowners in general because they eliminate the need for the digging, kneeling and stooping typically required to remove weeds. While we can appreciate the ease with which we can control weeds with just a few squirts of a weed killer, the effects of using such products can have dangerous and far-reaching health consequences. Eco-friendly weed killers can provide a safe alternative.
Herbicide exposure can have a toxic effect on humans and animals; how much of an effect depends on the particular herbicide and the level of exposure, according to the U.S. Environmental Protection Agency. Typically herbicides can enter the body through the skin, mucus membranes or by inhalation.
One common herbicide, 2,4-Dichlorophenoxyacetic acid, or 2,4-D for short, is found in more than 1,500 different herbicides. It is known to have a significant impact on people and animals that are exposed to high levels of the chemical. It can impact different parts of the body, including:
- Adrenal glands
- Ovaries or testes
- Thyroid gland
Another common herbicide, glyphosate, is reported to cause:
- Loss of the ability to control the muscles
- Breathing difficulties
- Rapid heartbeat
- Swollen eyes, eyelids and face
- High blood pressure
- Eczema, typically of the arms and hands
The Environmental Protection Agency is reviewing the status of glyphosate, as of publication time, due to the many safety concerns surrounding this chemical. Its use may be limited or revoked by the EPA by the end of 2015.
People typically get exposed to herbicides in two main ways: external exposure and ingestion. External exposure generally occurs either when you apply it or when you are in an area where the herbicide has been used. Ingestion occurs when you consume food that contains the herbicide. Both types of exposure can have harmful effects. Children are at higher risk of negative consequences than adults, since their brains and bodies are still developing.
The Impact of Inert Ingredients
Some weed killer formulas use a significant amount of inert ingredients, but the term can be misleading. In this case, the ingredients are only considered inert because they don’t kill weeds, not because they are neutral or don’t have any affect at all. According to an article in the Mother Earth News, some of these inert ingredients are added to commercial herbicide formulas designed for use by consumers.
The additives used are typically solvents, preservatives and surfactants -- ingredients that enhance how well the active ingredient is able to break through the weed’s defenses to make it easier for the product to kill weeds. Even if you read the label, you may not know just what’s in the weed killer you’re buying, because their identities are often kept secret. The problem comes from the fact that these same chemicals that allow the product to break through a plant’s defenses also allow it to penetrate human and animal cells more easily.
When one of these inert ingredients, such as polyethoxylated tallowamine, POEA, is added to an active ingredient such as glyphosate, it increases the effect of the active ingredient. At the same time, the active ingredient also enhances the effects of the inert ingredient so that the entire formulation is ultimately amplified far more than one would expect. This has the effect of making the weed killer stronger than expected with increased toxicity. POEA/glyphosate exposure can cause a low sperm count, infertility, prostate cancer and testicular cancer. It’s essential to take all possible precautions when using herbicides to prevent such negative outcomes.
Minimize the Risks
According to an article from Reuters, herbicides have been found in and on fruits and vegetables. Reduce the risk of ingesting herbicides by thoroughly washing all fruits and vegetables before consuming them. An article in Oprah Magazine, "How to Avoid Eating Pesticides," provides a list of foods that contain the most pesticides even after preparation. He suggests that you should always purchase organic versions of these foods, including bell peppers, apples, celery, peaches, spinach, potatoes, lettuce, nectarines, imported grapes, pears, cherries and strawberries. Other foods present much less risk and are generally considered safe after washing or peeling. Canned, frozen and dried foods typically have less pesticide contaminants than fresh foods because of the preparation process.
Weed killers are often applied to lawns, increasing the likelihood that children will be exposed. They are also used on recreational lakes and other public areas. Keep children and pets out of all such areas and avoid entering them yourself for a minimum of 24 hours to reduce chances of exposure.
Protect yourself from the hazards of applying weed killers by wearing protective gear. Use the product label as a guide for what to wear; make sure to read and follow all label directions. Protective items you should consider include:
- Long sleeves
- Long pants
- Rubber gloves
- Breathing mask
- Face shield
- Rubber boots
- Protective chemical suit from a garden or home center
Additional precautions to take include:
- Keep children and pets out of the area when applying herbicides
- Shower after applying
- Wash protective clothing immediately; never wash with other laundry
- Keep herbicides in their original containers
- Store products away from children and pets
- Never apply herbicide sprays on windy days, to minimize drift