HOME

About Aerias

The IAQ Resource

Just the Facts

Building Green

Premium Content

Contact Us


Pesticides
Pesticides: Germicides, Insecticides and Fungicides

Pesticides: Germicides, Insecticides and Fungicides What pesticides are Sources of pesticides Health problems associated with pesticides Decreasing exposure to pesticides What Pesticides Are Pesticides are products used to kill household pests. Pesticides can be an indoor air pollutant in many buildings because they are widely used to reduce many household pests, including those associated with indoor plants, pets, and wood and woolen products, and because they are tracked in from the outdoors. Pesticides used in and around the home include products to control insects (insecticides), termites (termiticides), rodents (rodenticides), fungi (fungicides), and germs (germicides or disinfectants). The suffix "-cide" means "killer" so care needs to be taken in using these products and instructions need to be carefully followed. In 1990, the American Association of Poison Control Centers reported that some 79,000 children were involved in common household pesticide poisonings or exposures. In households with children under five years old, almost one-half stored at least one pesticide product within reach of children. Federal law requires that most hazardous household products include specific types of information about the product on their labels. The Federal Insecticide, Fungicide and Rodenticide Act (FIFRA) regulates labeling of products that contain pesticides. All pesticides, including disinfectants, will have an EPA registration number since every pesticide must be registered with the US Environmental Protection Agency (EPA). Labels must contain the registration number (i.e., EPA Reg. No. __) and an establishment number (code for the manufacturer) (i.e., EPA Est. No. __). On June 8, 2000, the EPA announced that the popular pesticide Dursban would be phased out for home and garden use under an agreement with the manufacturers. Chlorpyrifos, the chemical found in Dursban, poses a risk to children because of its potential effects on the nervous system and possibly brain development. Dursban is the most widely used insecticide in the United States. Virtually all retail home and garden products containing Dursban are banned; all uses of Dursban in schools, day care centers, nursing homes, and shopping centers, among other places, are banned. However, the EPA has not ordered retail products containing Dursban to be pulled from store shelves. Sources of Pesticides Pesticides are used in more than 91% of households in the United States. Indoor contamination with pesticides is quite common. One study suggests that 80 percent of most people's exposure to pesticides occurs indoors and that measurable levels of up to a dozen pesticides have been found in the air inside homes. Reasons for that include contaminated soil or dust that floats or is tracked in from outside, stored pesticide containers, and household surfaces that collect and then release the pesticides. Pesticides sold for household use are a type of volatile organic compounds (VOCs) and include a variety of chemicals in various forms. They are sold as sprays, liquids, sticks, powders, crystals, balls, and foggers. Exposure to pesticides may cause harm if they are used improperly. According to the Centers for Disease Control and Prevention (CDC), one way of delivering pesticides that needs careful attention is the use of automatic insecticide dispenser units. These are found in restaurants, schools, hotels, offices, supermarkets, day care centers, hospitals, and long-term care facilities. They automatically spray a fine mist of 50 mg to 100 mg of insecticide. Some of the chemicals in these insecticides can cause skin rashes, eye irritation, asthma attacks, dizziness, salivation, headache, fatigue, vomiting, diarrhea, irritability to sound and touch, and other central nervous system problems. The CDC recommended that other methods of insect control be used. If these are used, they should have warning labels on them, they should not be installed near air supply ducts, and they should be set to dispense only when people are not around.¹ Contamination can happen if pesticides are misapplied. The only pesticides you should use are ones approved for consumer use. Otherwise, the results can be deadly. For example in Pascagoula and Hattiesburg, Mississippi, methyl parathion, a pesticide approved for outdoor-use only, was sprayed inside more than 2,600 homes and 100 businesses, including one day care. At least two children had previously died from indoor spraying. Methyl parathion (also known as "cotton poison") is usually sprayed in open fields to control insects. But unlicensed exterminators and homeowners illegally applied it indoors to kill roaches and other household insects. However, this has not just happened in Mississippi. According to the CDC, similar incidences have been reported in Ohio, Michigan, Alabama, Tennessee, Arkansas, Louisiana, Illinois, and Texas. As of June 1998, a total of 1863 persons in the U.S. had been relocated from 478 homes until the methyl parathion could be cleaned up.² If you decide to use a pest control company, choose one carefully. Ask for an inspection of your home and get a written control program to look over before signing a contract. The control program should list specific names of pests to be controlled and chemicals to be used; it should also reflect any of your safety concerns. Insist on a proven record of competence and customer satisfaction. You may also want to get information about the formulation, concentration, and methods of application. You can get this information by asking for the product's material safety data sheet or application documents and by asking the pest control contractor. You should receive satisfactory answers to any questions you have about the company's track record, insurance coverage, licenses, affiliation to professional pest control associations, and the proposed treatment. There is no further sale or commercial use permitted for the following cyclodiene or related pesticides: chlordane, aldrin, dieldrin, and heptachlor. The only exception is the use of heptachlor by utility companies to control fire ants in underground cable boxes. The EPA was concerned that these pesticides might cause long-term damage to the liver and the central nervous system, as well as an increased risk of cancer. Health Problems Associated with Pesticides According to the World Health Organization, more than 3 million people get sick, and 220,000 die worldwide from pesticides each year. In the United States alone, pesticides poison 110,000 people each year. Pesticides don't just affect humans. More than one-third of calls to animal poison centers result from pets exposed to pesticides. There are many factors that determine if one might get sick due to exposure to pesticides. These include: The type of pesticide. The concentration and amount of pesticide as well as its ability to evaporate into the air. Personal characteristics such as age, gender, weight and general health status. How one is exposed to the pesticides. Exposure to pesticides by accidentally breathing in spray mists may happen during normal use. One may also accidentally breathe in vapors from pesticides as well as contaminated dusts (particularly true for children and pets who may be in close contact with contaminated surfaces). Some pesticides can be absorbed through the skin and enter the bloodstream that way to be carried to different organs of the body. Is a person exposed to pesticides alone or together with additional chemical exposure? How long is one exposed to the pesticides? Generally, the longer the exposure, the more at risk one is. Most insecticides are highly toxic to humans. In addition to the active ingredient, pesticides are also made up of ingredients (usually VOCs) that are used to carry the active agent. Inert ingredients that may be responsible for many of the general health complaints are associated with indoor applications of pesticides. These carrier agents are called "inerts" in pesticides because they are not toxic to the targeted pest. However, some inerts are capable of causing severe health problems and research has shown that levels of VOCs in pesticides could be high enough to cause health complaints among certain individuals.³ Pesticide manufacturers are required to submit information about any human health effects from "inert" ingredients. Remember, "inert" DOES NOT MEAN "non-toxic"! Health problems caused by pesticides can either be acute which occur immediately or within a few days of exposure or they can be chronic which are long-term health effects that might not show up for many years. When pesticides are registered, they are subjected to tests that examine the acute or immediate hazard associated with that product. The signal word on the label can give you a general indication of the level of toxicity (lethal dose) of the product: "Danger/Poison" The most lethal type. Drinking a few drops to 1 tsp. of the product will kill the average person. "Warning" Drinking 1 tsp. to 1 ounce of the product will kill the average person. "Caution" Drinking over 1 ounce of the product will kill the average person. Some of the health problems that may be caused by both the active and inert ingredients in pesticides include: Irritation to the eyes, nose, and throat Headaches Blurred vision Nausea and/or vomiting Stomach cramps Diarrhea Loss of coordination Muscular weakness Damage to the central nervous system Damage to the liver Damage to the kidneys Increased risk of cancer Death Decreasing Exposure to Pesticides Areas treated with Dursban should be evacuated and allowed to dry at least four hours before people or pets re-enter. Prevent entry by inspecting plants and food products before you bring them indoors. Keep indoor spaces clean, dry, and well ventilated to avoid pest and odor problems. Eliminate or disturb the area where the pest resides. For example, the Los Angeles Unified School District is turning to patching cracks, pulling weeds, and steam-cleaning areas where pests breed instead of reaching for the pesticides. The National Coalition Against the Misuse of Pesticides (NCAMP) has found that more than 140 school districts have restricted or regulated pesticide use on school property.⁴ Control weeds in your yard and garden by first pulling them up either by hand or hoe. Pull weeds out with roots, or cut off weeds just below the surface with a hoe but try to minimize soil disturbance since that stimulates dormant weed seeds. To kill the roots and seeds of weeds and the insects in a selected area, cover area for four weeks to six weeks in the summer with clear plastic sheeting (1 mil thickness is fine), seal w/soil at edges. Wet soil thoroughly before putting down the plastic. Remove plastic before planting. Clear plastic heats sub-surface soil better than black. Cover areas of garden you want weed free with woven black garden fabric before you plant. Garden fabric lets water drain through while preventing weeds from growing. In lawns, sprinkle grass seed in bare areas after weeding to prevent weeds from returning. Mow your grass to two-inches, no shorter to discourage weed growth. Mow weekly to encourage the dense growth of grass shoots. Use nonchemical methods of pest control when possible. Examples include: Fly-swatters. Traps. In San Francisco, cockroach-eating geckos and gopher-eating snakes are being used to decrease use of pesticides. Use biological pesticides, such as Bacillus thuringiensis, for the control of gypsy moths. Products containing Bacillus thuringiensis are also good for getting rid of caterpillars. You can also get rid of caterpillars by introducing frogs, toads and lizards into your yard. Select disease-resistant plants. Wash pets and indoor plants frequently. Reduce or prevent termite damage by making sure that wooden building materials do not come into direct contact with the soil and by storing firewood away from the home. Appropriately fertilize, water, and aerate lawns, thus reducing the need for chemical pesticide lawn treatments To get rid of ants, first keep counters, floors and pet feeding areas clean. Remove and clean up whatever the ants are after. Then follow the ant trail and find out how they are getting in. Wipe up ants and ant trails w/soapy water. Caulk openings where they enter the house. Petroleum jelly in the cracks or duct tape can be a quick, temporary fix. Apply diatomaceous earth or silica gel into cracks. Apply a fine dusting to entry points that cannot be caulked. Then spread red chili powder or boric acid into cracks at point of entry. Since boric acid is a poison, be sure it is inaccessible to pets and children. To repel roaches, first close openings into house with caulking, screening, weather-stripping. Clean dishes nightly and seal all food containers. Do not leave pet food out overnight. Place chopped bay leaves and cucumber skins in the pantry, cupboards and on shelves to repel cockroaches. To repel nematodes (a type of parasitic worm) in your garden, plant marigolds To repel slugs and snails in your garden, plant onion and marigold plants. Trap wasps by suspending a piece of raw meat ½ inch over soapy water in a five-gallon bucket. To repel fleas and ticks from your pet, scatter pine needles, fennel, rye or rosemary on pet's bed. To repel fleas on your pets, feed them pet brewer's yeast, vitamin B or garlic tablets. To prevent pantry moths, put herbs that have insect-repellant qualities, (like bay leaves, coriander, dill, cinnamon, lemon peel, black pepper) on pantry shelves or even in stored grain. Vacuum and wash down pantry shelves to kill eggs. Store grains and flours in pest-tight containers (e.g. a glass jar with a rubber seal and a metal spring clamp). Plastic, zip-lock type bags are not adequate. Freezing newly purchased bulk grains for a week will guarantee no new moths. To keep mosquitoes away, the most important thing to do is remove all standing water near your house (tires, wading pools, bird baths, vases, barrels). If you have an ornamental pond, stock it with mosquitofish and use Bacillus thuringiensis in the pond to kill the larvae in the water. Use citronella oil insect repellents and burn citronella candles or oil at outside gatherings. Do not wear any strong smelling products like lotions, deodorants, hairspray, and sun tan oils. They attract mosquitoes. Also, install yellow porch lights since they do not attract flying insects. Also, encourage mosquito predators such as birds, frogs, turtles, ants, spiders, dragonflies, bats, and praying mantids. To keep away flies and other insects, first eliminate the breeding areas rather than trying to control adult flies after they emerge. Keep kitchen garbage containers tightly closed. Clean regularly. Sprinkle dry soap or kitty litter into bottom of container and keep a well-watered pot of basil around. Rinse out your recyclables, screen windows and doors, and check your yard for: Garbage cans with loose lids Fruit rotting under trees Pet waste not collected daily Compost piles that are not turned at least once a week and where decomposing food is not covered with dirt or black plastic To get rid of insects on plants, put soapy water on the leaves and then rinse. You can also take infested indoor plants outside for a couple of days (if not too cold) to let your yard's predatory bugs take care of your pest problem. To prevent fungus on roses, plant them in full sun, at least 3 ft. apart for good air circulation. Avoid over watering and remove and carefully dispose of dead or diseased leaves and flowers. Do not add them to the compost pile. To control mildew on roses, spray both sides of rose leaves with two2 tablespoons of mild liquid soap, two-thirds teaspoom baking soda in one gallon water. Spray in the morning, every week. For a disinfectant, wash items with water and soap, borax or sodium carbonate monohydrate (washing soda). Wash large surfaces with a solution of one-quarter cup borax dissolved in one-half gallon of hot water If you use a pest control company, select it carefully. Don't spray (for pests) by the calendar. Over application of pesticides is a common mistake. Rather than simply spray just because it is spring and you think bugs might start arriving, take a look around. Do not use pesticides if you do not need them. Do not store pesticides in the home and don't stockpile them. Keep on hand only what you need. Read the label and follow the directions. It is illegal to use any pesticide in any manner inconsistent with the directions on its label. Unless you have had special training and have been certified, never use a pesticide that is restricted to use by state-certified pest control operators. Such pesticides are simply too dangerous for application by a noncertified person. Use only the pesticides approved for use by the general public and then only in recommended amounts; increasing the amount does not offer more protection against pests and can be harmful to you and your plants and pets. Mix or dilute outdoors. Close windows to prevent outdoor sprays and dusts from drifting in. Apply only in recommended quantities. More is NOT better. Mix or dilute pesticides outdoors or in a well-ventilated area and only in the amounts that will be immediately needed. If possible, take plants and pets outside when applying pesticides to them. Clean shoes and hands before coming indoors to avoid bringing toxins inside Organic solvents may comprise a large percentage of the inert ingredients found in pesticides registered for indoor use. Because of this, ventilate areas well where pesticides are applied for 12 hours to 24 hours. Dispose of unwanted pesticides safely. If you have unused or partially used pesticide containers you want to get rid of, dispose of them according to the directions on the label or on special household hazardous waste collection days. Keep exposure to moth repellents to a minimum. Moth repellents may contain paradichlorobenzene, which is known to cause cancer in animals. Before storing clothes for the season, destroy all stages of clothes moths by cleaning garments before storing. Hang clothes in the sunlight and beat them to dislodge moth larvae and eggs Then store clothes in sealed bags with cotton gauze bags containing either cedar chips or two handfuls each of dried lavender and rosemary plus 1 tablespoon each of fresh cloves and dried lemon peel. Vacuum closets thoroughly. You can also store clean woolens in cedar chests or closets. If you do choose to use moth repellents containing paradichlorobenzene, be sure to store those items away from living and bedroom areas (in the attic, for example). Carefully consider whether you want an air duct-cleaning company to apply a biocide to kill mold. The EPA says biocides should be applied to air ducts only if necessary to control mold (ask the service provider to show the mold to you). As a precaution, you and your pets should leave during application. If you have any questions about pesticide use and safety, call the EPA-sponsored hotline at (800) 858-PEST. References Centers for Disease Control. Illnesses associated with use of automatic insecticide dispenser units - selected states and United States, 1986-1999. MMWR Weekly. 2000;49(22):492-5. Tinker TL, Collins CM, King HS, Hoover MD.. Assessing risk communication effectiveness: Perspectives of agency practitioners. Journal of Hazardous Materials. 2000;B73:117-127. Bukowski JA, Robson MG, Buckley BT, Russell DW, Meyer LW. Air levels of volatile organic compounds following indoor application of an emulsifiable concentrate insecticide. Environmental Science and Technology. 1996;30(8):2543-6. Locke M. Arcata is on the cutting edge of nontoxic pest control environment. Los Angeles Times, Sunday. July 2, 2000.