11 Tips to Minimize Pesticide Impacts on the Environment and Humans

by LUIS RODRIGUEZ, UF/IFAS Extension Polk County

Although pesticides are an effective method for pest control, when using pesticides incorrectly, these chemicals can negatively affect the environment and human health.

What Is the Environment?

The environment is composed of everything that surrounds us. This includes natural areas as well as indoor spaces and living spaces. The air, soil, water, plants, animals, humans, houses, restaurants, office buildings, schools, factories, and all they contain are part of the environment.

Sources of Contamination

There are two sources of contamination: point-source pollution and nonpoint-source pollution. Point-source pollution is contamination from a distinct identifiable source, for example, pesticide spills from a broken container. Non-point-source pollution is contamination where the origin is not from easily identifiable sources, for example, pesticide runoff, leaching and drift from multiple landscape pesticide applicators. Pesticide applicators need to do everything in their power to minimize these types of pollution to avoid negative interactions between pesticides and the environment.

What Applicators Can Do to Minimize Negative Pesticide Impacts on the Environment and Human Health?

Notify about applications – When doing applications, it is important to notify the nearby public to avoid unnecessary exposure. Notification is required by law, and a sign must be kept in the area (the time varies with the pesticide used) explaining the date of the application, re-entry interval, what pesticide was used in the location, and the contact information of the applicator.

Use pesticides only when needed – Pesticides are designed to control pests. If a particular location does not contain the presence of pests, the use of pesticides should be avoided.

Use the pesticide according to label instructions – The label is the law, and pesticide applicators need to follow all the instructions when applying the product.

Know the four pesticide characteristics and their interactions in the environment – Pesticides have 4 characteristics that need to be understood to avoid contamination:

Solubility: The ability of a pesticide to dissolve in water or another solvent. The more soluble the pesticide the more difficult it is to remove it from the solvent. Applicators using highly soluble pesticides need to take into consideration any non-target water body near their application site.

Adsorption: The ability of a pesticide to bind itself to soil particles. A pesticide that adsorbs itself to soil particles is less likely to leach out into groundwater. Adsorption is lower in sandy soil with low organic matter, which means leaching is more likely in these types of soil.

Persistence: The ability of a pesticide to remain present and active for an extended period. Nowadays, we are using pesticides that break down in the environment relatively quickly. Regardless, it is important to consult label instructions to understand how long the pesticide will remain active on the application site.

Volatility: The tendency of a pesticide to turn into a gas or vapor. In general, higher temperatures will increase the change of volatilization, although some pesticides have higher volatility than others. Applicators should read label instructions to avoid unnecessary contamination through pesticide vapors.

Avoid or minimize pesticide drift – Pesticide drift can be defined as the unintentional movement of a pesticide from a target location to an untargeted location. Low concentrations of drift are acceptable, but excessive amounts of drift could be harmful to the environment and human health. Furthermore, depending on the situation, excessive drift could end in legal problems. There are 3 types of drift:

Spray drift: This is the most common type of drift. It is the movement of a pesticide from the target location during a liquid application. To minimize spray drift, applicators should not apply pesticides in windy conditions, increase the droplet size of the nozzles, and verify their equipment calibration.

Vapor drift: This is the movement of a pesticide as vapor gas from the target location to a non-target location. To minimize vapor drift, applicators should avoid using highly volatile pesticides at high temperatures, avoid windy conditions, and verify their equipment calibration.

Particle drift: This is the movement of pesticide particles such as dust, granules, and pellets from the target location to a non-target location. To avoid particle drift, applicators should avoid windy conditions, use reflector shields when needed, and verify their equipment calibration.

Avoid spraying under bad weather conditions – As mentioned before, windy conditions could end up as unnecessary pesticide drift. Furthermore, applicators should avoid spraying during rainy days to avoid pesticide runoff.

Select the right boom for your equipment – Lower boom height helps to minimize pesticide drift. Applicators should avoid using a higher boom if possible.

Calibrate the equipment constantly – Calibration is important to avoid under or over-applications. Under-applications could end up in pesticide resistance while over-application could result in pesticide pollution.

Maintain equipment in good condition – Using faulty equipment when doing pesticide applications is against the law. Faulty equipment could end up in unnecessary pollution.

Be aware of sensitive areas – Sensitive areas are places where living creatures can be affected by pesticides. This includes schools, playgrounds, parks, reserves, apiaries, farms, hospitals, and other similar areas where wildlife and humans are present. To avoid possible problems in sensitive areas, many pesticide labels have special instructions on how to use them in sensitive areas. It is important to follow these instructions to avoid unnecessary risks and only use pesticides when needed.

Protect pollinators – Pollinators are important to agriculture and the environment. Applicators can do the following to protect pollinators:
Notify nearby beekeepers before the application is performed.
If possible, apply the pesticides at night when pollinators are less active.
Avoid spraying attractive blooms.
Avoid water contamination.
Use pesticides only when needed.

For more information about pesticides in the environment contact your local UF/IFAS Agent or access the following “Ask IFAS” publication:

Luis Rodriguez is the Polk County Small Farms and Pesticide Education Extension Agent. You can reach him at lrodriguezrosado@ufl.edu.