Source: Insects in the City
Will pesticides make a plant toxic?
Of course many insecticides, including some of the active ingredients in your tool kit, are used legally on crops all the time by farmers. This is allowed by the EPA only if that pesticide has been granted a tolerance for a given crop, and certain days-to-harvest intervals are followed. These rules work to ensure that any pesticide residues left after a pesticide application are below levels of concern for human health. The 2016 Pesticide Data Program survey by USDA shows that this system works. Out of 10,000 market food samples analyzed in the study, over 99 percent had residues well below the EPA established tolerances. More than 23 percent had no detectable pesticide residue.
So insecticide residues on plants are not necessarily toxic, especially when label directions are followed and adequate time passes to allow the product to naturally degrade. The products we use in pest control may be the same active ingredients used by farmers; but they may differ in concentration and formulation. Most importantly, pest control insecticides do not carry food-treatment labels so they cannot legally be used on edible crops.
Spray contamination
If an insecticide is deliberately sprayed on an edible crop or plant, and the product is not labeled for such use, the plant would not considered safe by EPA standards. The implication is that all of the plant, or at least the edible parts, should be thrown away. Your customer could replant, of course, unless prohibited by the label.
Of course applicators should always be aware of weather conditions and the locations of edible plants. If wind is blowing toward a garden, upwind applications should be avoided.
So what should you do if a fruit, nut, vegetable or herb is is accidentally over-sprayed? Such a plant should be pulled, or else the produce should be left uneaten or discarded, by the customer.
Washing
Regarding washing, your technician may want to suggest vegetable washing to a concerned customer whose nearby yard or house perimeter has been treated with an insecticide spray. Washing is a good idea whether pesticides have been used or not. The best washing technique includes a pre-rinse with a 10% vinegar solution (for germ control) followed by 30 seconds of tap water. This is a great way to remove urban dust, microorganisms and traces of pesticides from vegetable and fruit surfaces.
Would you recognize an edible plant?
When visiting a residence the first time, ask your customer if they have any herbs, fruit trees, nut trees or vegetables that you need to be aware of. Today’s gardeners are more likely to plant edible plants within flower gardens, so you might have a basil plant or a tomato plant growing among the daisies. Assume your customers are organic in their vegetable garden and avoid these areas accordingly.
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