1. REX MESSING Chapter 10: Pest Control

2. Pests and Pesticides A pest is something or someone that annoys us, detracts from some resource that we value, or interferes with a pursuit that we enjoy Biological pest- organisms that reduce the availability, quality, or value of resource useful to humans Based partly on perspective A mosquito annoys us but is a good food source for bats and birds Dandelions are considered weeds in the western hemisphere, but in some countries they are grown as a crop 100 plants, animals, fungi, and microbes cause 90% of all crop damage world wide Insects are considered to be the most frequent pest because they are ｾ of all species on earth Most tend to be generalist that reproduce rapidly and migrate quickly

3. Pesticides Pesticide- is a chemical that kills pests Not always toxic, some prevent development Other approaches to pest control are burning crop residues or draining wetlands to eliminate breeding sites Biocide- a broad-spectrum pesticide that kills a wide range of living organisms Herbicides- Kill plants Insecticides- Kill insects Fungicides- Kill fungi

4. Ancient Approaches Every culture has been known to use salt, smoke, or insect repelling plants to keep away pests or preserve foods Sumerians used sulfur 5000 years ago Chinese used mercury and arsenic 2500 years ago Alcohol from fermentation to prevent growth of organisms that would spoil food

5. Modern Pesticides DDT 1939 Swiss chemist Paul Muller created dichloro-diphenyl- trichloroethane Very lethal for wide range of insects Began to have bad affects on wildlife Rachel Carson’s Silent Spring EPA estimates that 5.3 billion pounds of pesticides are used per year About half is chlorine and hypochlorites for water purification Next largest category is conventional pesticides such as insecticides, herbicides, and fungicides 80% of all conventional pesticides are used for food storage of shipping According to CropLife America, 90 million ha of crops are treated with herbicides a year

6. Percentage of Pesticides used in the United States

7. Types of Pesticides Defined by chemical culture Inorganic pesticide- include compounds of arsenic, sulfur, copper, lead, and mercury Generally highly toxic and basically last forever Natural organic Pesticides- or “Botanicals,” generally are extracted from plants Ex. Nicotine, Rotenone, Turpentine Fumigants- small molecules that gasify easily and penetrate rapidly into a variety of materials Ex. carbon tetrachloride, carbon disulfide, or ethylene dichloride Chlorinated hydrocarbons- organochlorines that are synthetic organic insecticide that inhibit nerve membrane ion transport and block nerve signal transmission Ex. DDT, chlordane, aldrin, dieldrin, toxaphene Organophosphates- they inhibit cholinesterase, an enzyme essential for removing excess neurotransmitter from synapse in the peripheral nervous system Ex. parathion, malathion, dichlorvos, chlorphyrifose Carbamates- are extremely toxic to bees, but lack environmental persistence Ex. Urethanes, mirex Micro Agents- are living organisms or toxins derived from them used in place of pesticides

8. Benefits of Pesticides Controlling insect borne diseases: insects and ticks numerous pathogens and parasites malaria: DDT saved 50 million over 50 years yellow fever, Encephalitis, West Nile, sleeping sickness Without pesticides, we may lose two-thirds of conventional crops estimated that farmers save 3-5 dollars for for every $1 spent on pesticides CropLife America estimates that $21 billion dollars lost in food production Reduced up to 67% 70 million additional laborers to remove weeds by hand

9. Pesticide Problems Often poison nontarget species: Estimated that 90% of pesticides used never reach intended target Pest Resurgence- the idea of creating a population of pesticide resistant offspring through breeding 1000 insect species and 550 weeds have developed chemical resistance Pesticicde Treadmill- constantly try newer and more toxic chemicals in an attempt to stay ahead of the pests Tough because some genetically resistant genes are passed between species before a species is ever exposed to a pesticide Ex. 50 to 60 types of malaria carrying mosquito species are resistant to DDT because of widespread usage

10. Problems Cont. Misusage can create new pests: Broad spectrum pesticides are eliminating the lower number of beneficial predators Ex. Wasps, ladybugs, praying mantises Relying on pesticides overtakes traditional farming methods such as mixed crops, or rotation regimes Effective pesticides are stable, highly soluble, and highly toxic, making them the biggest nightmare Traces of pesticides are found many years later in areas that were not treated with pesticides Persistent Organic Pollutants (POPs)- are so long-lasting and so dangerous that they have been banned in 127 countries Dirty dozen: aldrin, clordane, dieldrin, DDT, endrin, hexachlorobenzene, neptachlor, mirex, toaphene, polychlorinated biphenyls (PCBs), dioxins, and furans

11. Human Health Affects Two categories: Acute effects such poisoning and illnesses caused by relatively high doses and accidental exposure Chronic effects suspected to include cancer, birth defects, immunological problems and other chronic degenerative diseases 25 million suffer pesticide poisoning and 20 thousand die each year from pesticide poisoning related diseases Two thirds of the results came from occupational exposure through usage without proper warning or protective clothing Hard to document specific cases for chronic affects of pesticide exposure but evidence shows problems Lower IQs, trouble focusing Ex. California children 3 times as likely to have acute lymphocytic leukemia when living in a once fumigated home

12. Alternatives to Current Pesticide Uses Improved management programs can cut pesticide use 50 to 90% without lowering crop production

13. Different Solutions Crop rotation can keep pest populations from building up Mechanical cultivation can substitute herbicides Flooding fields before planting or burning crop residues and replanting with a cover crop can suppress both weed and insect pests Habitat diversification prevents soil erosion and provides perch areas for nesting birds that eat pests Planting at different times and at different locations to avoid pests is another method Monoculture fields Tillage is effective at certain times of the year

14. Organisms That can Help with Pest Control Predators can control many pest cheaper and safer than broad-spectrum synthetic chemicals Naturally occurring bacterium that kills larvae but is harmless to mammals Ducks, chickens, geese, and other large species are used to rid fields of insects and pests Herbivorous insects have been used for weed control Some plants produce natural pesticides or repellents Genetics and bioengineering (GMOs) can help the fight against pests Use hormones that upset development or sex attractants to bait traps containing toxic pesticides

15. Integrated Pest Management Integrated Pest Management (IPM)- is a flexible, ecologically based pest control strategy that is applied at specific times and aimed at specific crops and pests Often uses mechanical cultivation and techniques such as vacuuming bugs off crops as an alternative to chemical application Tries to use minimum amount and avoids broad-spectrum pesticides Encourages plant defenses and diversity of beneficial organisms Trap crops Economic Thresholds- the point at which potential economic damage justifies pest control expenditures, and precise time, type, and method of pesticide application is critical in IPM Considered widely affective in the US and world wide Exposure 2.4 million metric tons of pesticides used in US every year contain 600 active ingredients 1200 presumably inactive carriers, solvents, preservatives, and other ingredients in about 25000 commercial products Less that 10% of active pesticide ingredients have received full tests Of 321 pesticides screened so far, 146 are probably human carcinogens 40 have been banned since 1972

16. Who Regulates Pesticides? 3 federal agencies: EPA: Environmental Protection Agency Regulates sale and use of pesticides under the Federal Insecticide, Fungicide, and Rodenticide Act (FIFRA) EPA determines which pesticides are the biggest risk Also sets levels of pesticides that may remain in in foods FDA: the Food and Drug Administration Enforce tolerance levels set by EPA Can seize and destroy any food shipment found to violate EPA limits USDA: the Department of Agriculture Enforce tolerance levels set by EPA Can seize and destroy any food shipment found to violate EPA limits

17. 12 Most Contaminated Foods 1. Strawberries 2. Bell Peppers 3. Spinach 4. Cherries (US) 5. Peaches 6. Cantaloupe (Mexican) 7. Celery 8. Apples 9. Apricots 10. Green Beans 11. Grapes (Chilean) 12. Cucumbers

18. Is Organic the Answer? Many farmers and buyers have gone to organic to avoid pesticide consumption More eco-friendly and leaves soil healthier Yields in organic plots are 20 percent less than conventional fields Net returns for organic farming was higher than conventional farming 56% less energy use on organic field Pest-eating predators found to be in greater abundance in organic fields 400 times less erosion than conventional farming Less than 1% devoted to organic growing in US More popular in Europe with 18% in Liechtenstein and 11% in Sweden

19. Organics Cont. “100% organic” must be produced without hormones, antibiotics, pesticides, synthetic fertilizers, or genetic modifications “Organic” means that at least 95% of the ingredients must be organic “Made with organic ingredients” must contain at least 70% organic ingredients Organic animals must be raised on organic feed, given access to the outdoors, given no steroidal growth hormones, and treated with antibiotics only to treat diseases

20. The Skeptics People doubt organic growers can produce enough food within these definitions to feed everyone They need chemical pesticides and large scale, chemical intensive farming to provide enough food for the portrayed world population It is thought that we can only produce enough food to feed 2 to 3 billion people without pesticides or synthetic fertilizers Potential health risks go along with eating organic food only “Bacteria and parasites are also all-natural”

21. Protect Yourself Wash and scrub all fruits an vegetables Peel fruits and vegetables when possible Store food carefully Cook or bake goods that you suspect to have been treated with pesticides Trim fat from meat, chicken and fish Don’t pick and eat berries or other wild fruits that grow on roadsides Grow your own fruits and vegetables Ask for organically grown food or shop at a farmer’s market