Pesticides: Background

Pests are living organisms that are either harmful or a cause of concern to humans and their surrounding environment. Pests may also have a negative economic impact. They come in all shapes and sizes. For instance, they can range from insects (e.g. cockroach) to plants (e.g. dandelion) to mammals (e.g. rats) to fungus (e.g. mold). As a result of this diversity, there are different types of pesticides that target them such as insecticides, herbicides, rodenticides, and fungicides. 

The term pesticide defines a chemical substance mixture of chemical substances used to prevent, eliminate, or repel pests.  There are different types of pesticides with different uses.  The general pest control categories include:

1. chemical pesticides,
2. biopesticides, and
3. pest control devices (Table 1). 

Humans can be exposed to pesticides via:

1. ingestion,
2. skin contact,
3. eye contact, or
4. inhalation.  

The risks associated with pesticides and the effects to human health vary based on age and lifestyle as well as dose, duration, and toxicity of the substance. The US Environmental Protection Agency (US EPA) uses a four-step process to assess risk. This process consists of:

1. identification of the health affects from exposure (hazard identification),
2. dose of the pesticide and the effects that develop (dose-response assessment),
3. how the exposure occurred (exposure assessment), and
4. a combination of the last three steps to describe the overall risk (risk characterization).

People that are sick, the elderly, those with asthma and allergies, and young children can be especially sensitive to toxic substances.   Chronic effects potentially caused by pesticides include:

1. damage to the nervous system,
2. development of cancer,
3. harm to the reproductive system,
4. changes in hormone function,
5. impairment of fertility, and
6. effects to the immune system.

The use of pesticides in the home can be risky and therefore caution should be taken. First and foremost, it is extremely important to follow the directions and precautions indicated on the label (Figure 1). Understanding this information increases safety and effectiveness. Look for such words as “caution” or “warning” that signify that the product can be toxic to humans or pets. Make sure that the pesticide that you are using is appropriate to kill the targeted pest. Keep the product in the original bottle since it contains important information such as first aid instructions, assistant phone number, and product handling instructions.

It is also extremely dangerous to place pesticides in food or beverage containers since those that are not aware may think that what is inside can be consumed. Puncture used pesticide containers in order to prevent reuse. It is also important to keep pesticide containers out of the reach of children and pets. Use locked cabinets, store out of reach, and make sure tamper proof caps are secure. Remember, the safety of a pesticide has to do with how you use and store it. In the U.S., approximately 87 people die per day as a result of unintentional pesticide poisoning, and another 2,277 per day are treated in emergency departments (Centers for Disease Control and Prevention, 2012).

Precautions should be taken when dappling pesticides inside and outside of the home. If it is being applied indoors, open windows to promote good ventilation. Always, wear gloves and eye protection to avoid exposure (especially on a windy day). It is also important to wear protective clothing. Remember, if a pesticide falls on the protective clothing, wash separately from your other clothes. Do not eat, chew gum, or smoke when applying pesticides or near a recently treated area. Keep children or pets away from any spills and promptly clean-up as indicated in the product instructions. Dispose of any rags or containers properly that have been used to clean up the spill.

pesticide background figure 1.png

Always apply only what you need. The product effectiveness might have an expiration date; therefore a larger size might not be a better value after all. If you have pesticide left over, you can pass them on to someone else who use them or dispose of them properly (e.g. designated hazardous waste drop off locations). Do not apply these products near rain or storm sewers so they do not enter drainages or waterways. Never pour pesticides down the household drain.

Within agriculture fields, pesticides are applied to large areas. Therefore, workers that apply pesticides and those living near agricultural fields are the most at risk to exposure of these substances. If you live adjacent to a field, make sure that you close the windows in your home when they are spraying or during a windy day.  Dust and air that may enter your home may contain pesticides. Research studies suggest that the amount of pesticide dust found in the home is related to how close the home is to agriculture fields (Beamer, 2011).

If you or a family member works in agriculture fields, it is important to take certain steps to decrease exposure. Before leaving the work site, either shower or wash body parts that have been exposed to pesticides in addition to changing your clothes. Studies show that a likely pathway that introduces pesticides into the home is the family car (Beamer, 2011). Therefore, it is important to decontaminate at the work site before entering the vehicle. Lastly, be sure to practice safe handling of pesticides at work since it can decrease exposures at home.

Integrated pest management (IPM) is a management philosophy that combines various practices to minimize pests. It combines knowledge about the lifecycle and tendencies of pests, application of the proper pest control methods, and common sense prevention techniques. It has been applied both in and around the home as well as agricultural sites. It is considered effective and environmental friendly. This management approach may be more time consuming, but in the end it is safer and less costly.  The following are the general steps (Table 2):

An important part of IPM is the prevention of pest infestation in the home and garden. There are precautionary steps that can be taken to decrease the likelihood of pest problems. The following are less harmful suggestions to prevent pests in your home (Table 3):

When it comes to gardening or agriculture, additional steps can be taken in order to decrease pest invasions than those already presented. It is important to properly care for flowers, trees, and vegetables. A healthy plant resists pests much better than a weak plant. Make sure you have healthy soil, which promotes healthy plants. Different types of crops should be planted in the garden, since a pest might prefer one type and cannot easily spread to others. Have a realistic goal when it comes to weeds. It is impossible to get rid of all weeds, so keep them to a minimum. Lastly, make sure that all water is drained in order to prevent plant disease as well as insect reproduction. 

Pesticide alternatives can decrease exposure and are considered less toxic than conventional methods. When using pesticide alternatives around the home, it is important to identify where the pests are entering and the time of day they seem most active. The following chart summarizes some of the alternatives to common pesticides used around the home:

*Follow products instructions; these are only general use suggestions.