Enironmental Education Specialist

There has been a great deal of interest and concern about the presence and risk of pesticides in our daily lives from the food we consume to the chemicals used for turf maintenance. One obvious component in risk calculations is the inherent toxicity of the product. Another component of the risk equation is exposure. For lawn applied pesticides, the exposure is primarily dermal and there have been several interesting studies conducted to evaluate the likelihood of exposure to these products. The person most likely for exposure to lawn products is the applicator. Commercial applicators in Michigan are required to be trained on how to use personal protective equipment to minimize exposure. This discussion however, is directed toward the likelihood and degree of exposure to people using the lawn area after the products have been applied. To investigate this area, we first need to gain an understanding of the fate or destination of these products after they are applied. Once the solution hits the target zone, there are four general places the product can go. It can be absorbed into the plant, adsorbed onto the leafblade, adsorbed onto the soil/thatch area, or volatilized into the air. There are many factors that influence the amount of pesticide product that can be accumulated in any of these areas. They include the product formulation (dry, liquid, EC, WP), temperature, moisture, humidity, turf density, and time after application to name a few. What we are concerned about is the dislodgeable fraction, or the amount left on the leaf blade that is able to be removed or rubbed off by a person