Pesticides have been found in outdoor air samples. Where do they come from? They could be originating from local, regional or global sources. Locally, pesticide drift may be a factor. Pesticide drift is when pesticides unintentionally move from the application site. Drift is more likely to occur with fumigants (gasses), dusts or when liquid pesticides are applied as a very fine mist. Drift is also more likely to occur on windy days and when temperatures are very high.
In addition to pesticide released locally, pesticides in the air can rise to very high altitudes and move for long distances attached to particles. Scientists have found that particles released in the atmosphere in Asia can reach the forests and national park on the west coast of the United States in less than a week. Particles traveling across the United States from the mid-west to the east coast to the Atlantic Ocean and Europe travel in what is called a boundary layer. The Gulf Stream can transport particles from Florida to Maine. These particles can enter our ecosystem when they are deposited as rain or snow.
If you have questions about this, or any pesticide-related topic, please call NPIC at 1-800-858-7378 (8:00am - 12:00pm PST), or email us at firstname.lastname@example.org.