What is metam?
Metam is the name of a compound commonly used as a pesticide in general purpose soil fumigants. Metam compounds often appear as “metam-sodium” or “metam-potassium” on ingredient labels. When applied, the metam in the fumigant rapidly breaks down into the active ingredient, MITC, an effective pesticide used to control a variety of pests that threaten food and non-food crops.
Why is metam used?
Metam is an effective pest control fumigant that reduces a variety of threats to crops resulting in less use of additional pesticides. Use of metam leads to less environmental impact, higher crop yields, higher farm profits and lower food prices. Metam fumigants are recognized by the EPA as a suitable replacement for other fumigants that don’t have the same safety profile or efficacy.
How long have metam soil fumigants been in use?
Metam soil fumigants been approved for use in over 15 countries for more than 40 years
How are metam soil fumigants used?
Metam-based soil fumigants are some of the most widely used soil fumigants in the U.S. They are primarily used on commercial farms by or under the supervision of certified personnel. Metam-based fumigants are not intended for use by the general public.
Metam fumigants are applied to the soil using specialized equipment after harvest and/or 14-21 days before a new crop is planted. Following application of a metam fumigant, the soil can be covered to enhance the efficacy of the fumigant and keep it in the soil.
Does metam or or other fumigant ingredients get into our food?
Metam fumigants are only used on soil, they are never in contact with the crops grown in the field. As a result, there is little risk of dietary exposure to metam fumigants. “Risk from dietary exposure to metam sodium, metam potassium or MITC is not of concern for all registered uses under the current conditions of use.” (Health Canada 2017)
Are there risks of exposure to metam?
The U.S. EPA and other regulators extensively review studies on the safety of metam fumigants before they can be registered and re-registered for use. These studies assess the risk of exposure to metam fumigants and determine how exposure might impact human health. These regulators set strict directions on how metam is to be applied, and how to prevent workers in the field and bystanders from exposure.
When these directions are followed, the exposure to metam by anyone on or near a field where the fumigants are being applied is managed. In 2017 the leading health authority for Canada stated “metam sodium and metam potassium are unlikely to affect human health when used according to label directions.” (Health Canada 2017)
Is metam harmful to the environment?
A 2017 evaluation by Health Canada found “….when used according to the label directions, metam sodium and metam potassium are not expected to pose risks of concern to the environment.” Metam is highly regulated by federal and state governments to insure its safe and effective use. This oversight and regular evaluation includes directives on containing metam fumigant in the fields and also preventing human and environmental exposure. These directives are part of the “label” for metam products which include ensuring fields are clearly marked and buffer zones around fields are observed. Additionally, directives on weather conditions and time of day for application are part of the label to minimize risk of off-target landing of the fumigant.
Does metam accumulate in the soil and harm it?
One of the most important resources to a farm is the soil. Growers must balance the use of methods to control pests with soil health. Through good agricultural practices and guidelines, metam fumigants play an important role in protecting soil and crop health while controlling pests.
When applied, the metam in the fumigant rapidly breaks down into the active ingredient, MITC (methyl isothiocyanate), an effective pesticide used to control a variety of pests that threaten food and non-food crops. MITC is highly volatile and will break down quickly when exposed to the atmosphere therefore reducing environmental exposure to the active ingredients of the fumigant.