Definition: any chemical used to kill pests.

Transcription

1 I. Pesticides Definition: any chemical used to kill pests. A. In the U.S., over 700 active ingredients plus 1200 inert ingredients are mixed to make 50,000 individual pesticide products.

2 I. Pesticides B. Types and Usage: TYPES Targets (kills) Percent Herbicides Insecticides Fungicides plants 85% insects 10% fungi 4%

3 I. Pesticides B. Types and Usage: Croplands USAGE Government & Industrial Lands Households Forests PERCENT 77% 11% 11% 1%

4 I. Pesticides B. Types and Usage: About 20% of pesticides are applied to lawns, gardens, parks, and golf courses. 91% of US households use pesticides indoors. Average homeowner uses 5X more pesticides per unit of land area than farmers.

5 I. Pesticides C. Pesticide Benefits 1. Disease Control a. Malaria 1) 300 million people suffer. 2) 1 million deaths each year. 3) 50 million deaths prevented over the last 50 years because of pesticide control of mosquitoes. b. Other diseases spread by biting arthropods: 1) Yellow fever (mosquitoes) 2) Encephalitis (mosquitoes) 3) West Nile virus (mosquitoes) 4) Sleeping sickness (tsetse fly) 5) River blindness 6) Elephantiasis (tiny worms transmitted by flies)

6 I. Pesticides C. Pesticide Benefits 2. Crop Protection Cropland America calculates that without pesticides in the U.S. there would be: a. 21 billion $ per year loss in food and fiber. b. 67% reduction in crop yields.

7 II. Weed Control A. Weed: undesirable or unwanted plant.

8 II. Weed Control B. Weeds create numerous problems for humans. Compete for water and nutrients. Act as alternate host for insect and fungal pests. Can be toxic to range animals. Thorns can open wounds that can invite infection and/or insect pests. C. Life Cycles of Plants 1. Annual completes life cycle in one year or less. 2. Biennial completes life cycle sometime in second year of development. 3. Perennial lives from year to year with varying blooming periods.

9 II. Weed Control D. Examples of Some Arizona Weeds 1. Types of poisonous plants a. Plants that always possess toxins. 1) Datura (Jimsonweed)

10 II. Weed Control D. Examples of Some Arizona Weeds 1. Types of poisonous plants a. Plants that always possess toxins. 2) Silverleaf Nightshade (Solanum elaeagnifolium)

11 II. Weed Control D. Examples of Some Arizona Weeds 1. Types of poisonous plants b. Plants that develop toxins under stress. 1) Johnson Grass (Sorghum halepense)

12 II. Weed Control D. Examples of Some Arizona Weeds 1. Types of poisonous plants b. Plants that develop toxins under stress such as HCN or nitrate accumulation. 2) Russian Thistle (tumbleweed) (Salsola kali)

13 II. Weed Control D. Examples of Some Arizona Weeds 2. More pest plants. a. Examples from your backyard. 1) Prostrate spurge (Euphorbia supina)

14 II. Weed Control D. Examples of Some Arizona Weeds 2. More pest plants. a. Examples from your backyard. 2) Sheperd s purse (Capsella bursa pastoris)

15 II. Weed Control D. Examples of Some Arizona Weeds 2. More pest plants. a. Examples from your backyard. 3) Wild barley (Hordeum leporinum)

16 II. Weed Control E. Examples of common herbicides D (Weed-B-Gon) Non-toxic, breaks down easily Selective nature Kills broadleaf dicots, not monocots (grass) Economically significant for lawns and crops monocot grains

17 II. Weed Control E. Examples of common herbicides. 2. Glyphosate (active ingredient) Roundup, Doomsday, Kleen-up (trade names). Non-selective. Kills everything. Contact systemic. Useful in converting lawns to xeriscape.

18 II. Weed Control E. Examples of common herbicides. 3. Pre-emergants Surflan (trade name) Kills both seeds and seedlings.

19 III. Potential Problems from Pesticides Up to 90% of the pesticides never reach their targets. A. Bioaccumulation: accumulation of toxins in tissues of individual organisms. Examples: 1. 20% of all honeybees in the U.S. are destroyed by pesticides each year. 2. In 1972, a single application of the insecticide Azodrin to combat potato aphids on a farm in Dade County, Florida killed 10,000 migrating robins in 3 days.

20 III. Potential Problems from Pesticides B. Biological magnification/amplification: bioconcentration of fat soluble toxins that concentrate in the bodies of predators such as: Porpoises Whales Polar bears Tuna Raptors (eagles, etc.) Humans

21 III. Potential Problems from Pesticides B. Biological magnification/amplification: bioconcentration of fat soluble toxins that concentrate in the bodies of predators:

22 III. Potential Problems from Pesticides B. Biological magnification/amplification: Examples: 1. In 1999, researchers found p,p DDE (a DDT breakdown byproduct in the amniotic fluid of 30% of a sample of pregnant L.A., California women. DDT was banned in the U.S. and Canada in the late 1970 s!! 2. Other biomagnified toxins: a. Persistent Organic Pollutants (POP s) Examples: PCB s (polychlorinated biphenyls) Dioxins Dieldrin Aldrin

23 III. Potential Problems from Pesticides B. Biological magnification/amplification: Examples: 2. Other biomagnified toxins: b. Toxic Metals Examples: Lead

24 III. Potential Problems from Pesticides B. Biological magnification/amplification: Examples: 2. Other biomagnified toxins: b. Toxic Metals Examples: Lead Mercury Nickel Beryllium c. Halogens Examples: Fluorine Chlorine Bromine Iodine

25 III. Potential Problems from Pesticides 3. Increase in pesticide resistance. The Worldwide Institute reports that at least 1000 insect pest species and 550 weeds and plant pathogens worldwide have developed chemical resistance. Compound Bollworm Tobacco Budworm DDT

26 III. Potential Problems from Pesticides F. Some potential problems from pesticides. 3. Increase in pesticide resistance.

27 III. Potential Problems from Pesticides 4. Synergy. Relatively harmless compounds that form hazardous combinations after release. Examples: (Widely used pesticide.) Endosulfan (Banned pesticide that lingers.) Dieldrin Endosulfan/Dieldrin ( X the estrogen potential.)

28 IV. Toxins & Your Health: Endocrine Disruptors A. Endocrine disrupters are chemicals that may interfere with the body s endocrine system and produce adverse neural, immune, developmental, and in reproductive effects both humans & wildlife. A wide range of substances, both natural and man-made, are thought to cause endocrine disruption, including: 1. Parabens : preservatives in foods & cosmetics)

29 IV. Toxins & Your Health: Endocrine Disruptors A. Endocrine disrupters are chemicals that may interfere with the body s endocrine system and produce adverse neural, immune, developmental, and in reproductive effects both humans & wildlife. A wide range of substances, both natural and man-made, are thought to cause endocrine disruption, including: 1. Parabens : preservatives in foods & cosmetics)

30 IV. Toxins & Your Health: Endocrine Disruptors A. Endocrine disrupters are chemicals that may interfere with the body s endocrine system and produce adverse neural, immune, developmental, and in reproductive effects both humans & wildlife. A wide range of substances, both natural and man-made, are thought to cause endocrine disruption, including: 1. Parabens : preservatives in foods & cosmetics) 2. Plasticizers: such as Bisphenol A(BPA), found even in dental sealants. 3. Pharmaceuticals: such as Prozac found in bass in Texas lakes. 4. Pesticides: DDT, atrazine, and other organophosphates. 5. Phthalates: used in cars, clothing, food packaging, medical devices.

31 IV. Toxins & Your Health: Endocrine Disruptors B. Endocrine disruptors may be found in everyday products: 1. Plastic bottles 2. Metal food cans 3. Detergents 4. Flame retardants 5. Foods 6. Toys 7. Cosmetics 8. Pesticides

32 IV. Toxins & Your Health: Endocrine Disruptors C. The NIEHS (National Institute of Environmental Health Services) supports studies to determine whether exposure to endocrine disruptors may result in human health effects including: lowered fertility, and an increased incidence of, endometriosis and some. cancers Research shows that endocrine disruptors may pose the greatest risk during prenatal and early postnatal development when organ and neural systems are forming.

33 IV. Toxins & Your Health: Endocrine Disruptors

34 IV. Toxins & Your Health: Endocrine Disruptors D. Pesticide Toxicity in Humans: 1. Globally, it s estimated that 1.5 million people are poisoned by pesticides annually % suffer chronic health problems, i.e., neurological damage and dermatitis ,000 40,000 die annually. 4. In the United States, 20,000 Americans, many of them children, become sick because of unsafe use and storage of pesticides. 5. Next to medicines, pesticides are the SECOND leading cause of child poisoning.

35 IV. Toxins & Your Health: Endocrine Disruptors D. Pesticide Toxicity in Humans: 6. Agent Orange plant defoliant a. Used in Vietnam to clear the jungle cover

36 IV. Toxins & Your Health: Endocrine Disruptors D. Toxicity in Humans:

37 I. Pesticides C. Toxicity and humans: OVERFLOW! RESULT: POLLEN FOOD ALLERGIES STRESS MOLDS PESTICIDES DRUGS DUST AUTO EXHAUST INDUSTRY CHEMICALS ENVIRONMENTAL ILLNESS!

38 IV. Toxins & Your Health: Endocrine Disruptors D. Toxicity In Humans: ENVIRONMENTAL ILLNESS!

39 V. Alternatives to Current Pesticide Uses A. Behavioral Changes: Examples: Crop rotation Mechanical cultivation Habitat diversification

40 V. Alternatives to Current Pesticide Uses B. Biological Control: 1. Use of predators & pathogens. Bacillus thuringiensis serovar israelensis -- Bt spores used as a larvicide Ladybugs preying on aphids.

41 V. Alternatives to Current Pesticide Uses B. Biological Control: 2. Natural pesticides and insect repellents. Pyrethrum is a natural plant oil that occurs in the pyrethrum daisy (Tanacetum cinerariaefolium). Affects the central nervous systems of many types of insects, blocking nerve junctions. Is effective against more than 40 common garden insects.

42 V. Alternatives to Current Pesticide Uses B. Biological Control 2. Natural pesticides and insect repellents. Citronella is an oil from the leaves of citronella grass

43 V. Alternatives to Current Pesticide Uses B. Biological Control 3. Genetics & bioengineering. [Development of Bt crops]

44 V. Alternatives to Current Pesticide Uses B. Biological Control 3. Genetics & bioengineering. Bacillus thuringiensis (Bt) is a soil bacterium that produces insecticidal toxins. Bt spores/crystals Genes from Bt can be inserted into crop plants making them produce an insecticidal toxin and resistant to certain pests. Bt corn can adversely affect nontarget insects if they are closely related to the target pest, as is the case with Monarch butterfly. Corn borer larvae Monarch

45 V. Alternatives to Current Pesticide Uses B. Biological Control 4. Hormones & pheromones. Female moths attract males with sex pheromones. Males detect them with their antennae. Males enter field traps & are coated with artificial female pheromone. Males overloaded with female pheromones are unable to locate the females. Pheromone laden males act as a false lure. They are detected by newly emerged males and pass on the pheromone through false mating. Females delayed in finding a mate have fewer offspring.

46 V. Alternatives to Current Pesticide Uses B. Biological Control 5. Sterile males. Sterile males + females mating once = inviable eggs (eradication) Adult screw worm fly. Flesh eating larvae. Rearing gama irradiated sterile males. Sterile males are released over infested areas.

47 V. Alternatives to Current Pesticide Uses C. Integrated Pest Management A flexible, ecologically based pest-control strategy that uses a combination of techniques applied at specific times, aimed at specific crops and pests. pheromones pesticides IPM Natural predators Crop rotation Sterile males bioengineering

48 V. Alternatives to Current Pesticide Uses B. Wolff Vineyards Certified Sustainable Practices 1. Water conservation 2. Pest management 3. Habitat restoration & working with wildlife