Pesticide Spray Drift Pesticide Spray Drift Definition Pesticides are used to control specific pests within specific areas. Pesticide applicators are licensed and must carefully manage the use of these chemicals and tools to achieve an accurate application. There are many factors that the applicator must understand in order to minimize pesticide spray drift. “Spray drift is the physical movement of pesticide droplets through the air at the time of pesticide application or soon thereafter from the target site to any non- or off-target site. Spray drift does not include movement of pesticides to non- or off-target sites caused by erosion, migration, volatility, or windblown soil particles that occurs after application or application of fumigants unless specifically addressed on the product label with respect to drift control requirements.” (Based on the definition of the National Coalition on Drift Minimization). Off-target spray can affect human health and the environment. For example, spray drift can result in pesticide exposures to farmworkers, children playing outside, and wildlife and its habitat. Drift can also contaminate a home garden or another farmer’s crops, causing illegal pesticide residues and/or plant damage. The proximity of individuals and sensitive sites to the pesticide application, the amounts of pesticide drift, and toxicity of the pesticide are important factors in determining the potential impacts from drift. EPA recognizes the importance of exposures to pesticides resulting from spray drift. There are thousands of reported complaints of off-target spray drift each year. Reports of exposures of people, plants, and animals to pesticides due to off-target drift (often referred to as “drift incidents”) are an important component in the scientific evaluation and regulation of the uses of pesticides. Other routes of pesticide exposure include consuming foods and drinking water that © 2014 All Star Training, Inc. 1 may contain pesticide residues, applying pesticides, and contacting treated surfaces in agricultural, industrial, or residential settings. EPA considers all of these routes of exposure in regulating the use of pesticides. When labels of pesticide products state that off-target drift is to be avoided or prohibited, EPA’s policy is straightforward: pesticide drift from the target site is to be prevented. However, EPA recognizes that some degree of drift of spray particles will occur from nearly all applications. Nevertheless, applicators and other responsible parties must use all available application practices designed to prevent drift that will otherwise occur. In making their decisions about pesticide applications prudent and responsible applicators must consider all factors, including wind speed, direction, and other weather conditions; application equipment; the proximity of people and sensitive areas; and product label directions. A prudent and responsible applicator must refrain from application under conditions that are inconsistent with the goal of drift prevention, or are prohibited by the label requirements. EPA uses its discretion to pursue violations based on the unique facts and circumstances of each drift situation. Pesticide applicators and others, including landowners, play a very important role in pesticide application—deciding whether or not to apply a pesticide and if so how best to make that application. It is their responsibility to know and understand a product’s use restrictions. They are responsible for complying with all other pesticide laws regarding pesticide applications and ensuring that their application equipment and techniques will produce a minimum of spray drift. EPA also expects applicators to exercise a high level of professionalism in making decisions about applications. To understand how to minimize spray drift, we must first understand what causes it. There is a distribution of different droplet sizes in the spray leaving the nozzle during pesticide applications. Smaller droplets may sometimes stay suspended long enough to move to a non- target site, while larger droplets have less propensity for such movements. Application equipment factors have a significant influence on the droplet size, while tank mix components (pesticides, water and/or oil, and any adjuvants) have a much less significant effect. Weather © 2014 All Star Training, Inc. 2 conditions, natural and man-made physical barriers, and type of target site, are additional factors which will influence spray drift. Research has shown that for most applications, some spray drift will occur. This is not necessarily unacceptable, as very small amounts of most pesticides will generally not affect non- target sites. However, great precautions should be taken to minimize drift where highly sensitive sites are known to be in close proximity. Highly sensitive sites include areas occupied by humans, non-target crops, wildlife habitat, aquatic habitats, and organic farms. Special laws also apply to endangered species. Types of Pesticide Drift There are two types of drift: spray drift and post-application drift. Spray drift occurs during and immediately after a pesticide application. Post-application drift occurs after the application is complete, hours and even days later. Spray drift Spray drift occurs during and immediately after a pesticide application when wind or application equipment blow spray droplets, dust or gases off the intended site. The pesticide droplets sprayed out of nozzles are the most problematic and can drift long distances before settling. These pesticides may be applied by a crop duster, airplane or by a tractor. Applicator error can cause drift; however, even when pesticides are applied correctly, drift can still occur. Post-application drift Post-application drift occurs after application is complete, hours and even days later. There are two types of post-application drift: Volatilization drift Some pesticides are applied as liquids or oils but then evaporate (or “volatilize”) into a gas after they are applied to crops or fields. Once in gas form, volatile pesticides can drift long distances. © 2014 All Star Training, Inc. 3 Fumigant pesticides (used to treat homes, storage bins, and soil before planting) are especially volatile, and pose the worst problem of all drifting pesticides. Unlike spray drift or drift of dust particles, volatilization drift is invisible, making it difficult to detect without monitoring equipment. Drift of pesticide-coated dust particles Sometimes high winds in agricultural areas create clouds of dust from pesticide-treated fields. This dust may end up in yards and parks, as well as in homes and cars, where it can be inhaled or ingested. Children are particularly vulnerable to this type of exposure because they play on the floor and often put their hands or other objects into their mouths. Most pesticides can become adsorbed to dust and be transported in this way. Pesticide Poisoning Pesticides and Human Health Just as smokers have a higher risk of getting lung cancer, emphysema, and heart disease than non-smokers, studies show that people who regularly work with pesticides have a significantly elevated risk of certain types of cancer, neurological disorders, respiratory disease, miscarriages and infertility relative to a control group with less pesticide exposure. But exposure to airborne pesticides is not limited to workers, nor are the associated diseases and conditions. The ability of pesticides to drift away from where they are applied ensures secondhand exposure opportunities for those who just happen to be in the area, through breathing pesticide-contaminated air or dust and contact with surfaces contaminated by residues resulting from pesticide drift. Two types of poisoning can result from exposure to pesticide drift: acute and chronic. Acute poisonings cause symptoms soon after the exposure occurs. Symptoms of acute poisoning are usually obvious, such as eye, skin and respiratory irritation, asthma attacks, nausea, vomiting, headache, tremors, numbness and more. Symptoms may mimic those of flu, colds and headaches. Farmworkers, their families, farmers and “fence-line” communities are on the front lines for this type of poisoning. Chronic poisoning is a result of pesticide exposures, often at low levels, over a long period of time. Like secondhand cigarette smoke, chronic exposures to drifting pesticides can have long- © 2014 All Star Training, Inc. 4 term health effects, even though people may experience few or no symptoms until long after their exposure. People affected by pesticide drift The developing fetus, infants, and young children are the most vulnerable to both acute and chronic health effects from drift. Both urban and rural communities can be affected by drift. Farmworkers are most at risk of pesticide drift exposure because of their proximity to and involvement with pesticide applications. While it is illegal to spray a field occupied by workers, no law prevents spraying a field located beside another with workers present. Organic farmers suffer economic damage when contamination from drift lengthens the time required to obtain organic certification, disqualifies produce for the certified organic label and disrupts beneficial insect populations. Even conventional farmers can sometimes lose part of their crop because of drift. Residents in suburbs on the agricultural-urban interface and people living or working in agricultural communities have daily exposure to multiple pesticides from post-application drift of pesticides. Urban residents