JBHA 12 23

JBHA 12 23
Pesticide Dilemma
Bug – vac
1. Pesticide types
A. Narrow- spectrum-kills only intended vic’s
a. The perfect situation- stays localized
B. Broad-spectrum- non redily degradable and transfer location
C. First/Second Generation
a. Pre 1940= inorganics – Pb, Hg, Arsenic
b. Botanicals
i. Tobacco- nicotine
ii. Chrysanthemum- pyrethrin
iii. Derris- rotenone
c. Synthetic botanical
i. Non persistant Pyrethroids
D. Second Generation- modern synthetics- DDT
2. Major Insecticides
A. Chlorinated hydrocarbons- broad based, slow to degrade, used to 1960’s
B. Organophosphates- since 1940’s, more dangerous
C. Carbamates (not Carabas)-broad based yet safe to animals
D. control diseases- malaria
3. Herbicides
A. Selective- kills only certain plants
B. Non-selective- wipes out all (Agent Orange)
C. Broad-leaf- no grasses
D. Grass- safe for most plants
2,4-D and 2,4,5 trichlorophenoxyacetic acid
E. Viet Nam- defoliant
“From 1961 to 1971, Agent Orange was by far the most widely used of
the so-called "Rainbow Herbicides" employed in the herbicidal warfare program. During the production of
Agent Orange (as well as Agents Purple, Pink, and Green) dioxins were produced as a contaminant,
which have caused numerous health problems for the millions of people who have been exposed.”
1. Crop Rotation
A. Pests consume- 30% of world’s crops
B. Pathogens – fungi , bacteria are also controlled
C. cost- benefit- farmer Jane saves$3-5 in crops for every $1 pesticide
D. Monoculture- large tracts of one crop
2. Genetic Resistance
A. Developed- adaptation, 500+ species
1. ED 50 and LD 50 in action
Treadmill- increased pesticide use, higher costs, decline of crop yield
3. Resistance Management
A. Refuge- allows a slow-down in genetic resistance, allowing pop % to not be sprayed,
mate and zap the new population.
4. Imbalances
A. Non selective chems kill predators as well; allows greater pest pop to enlarge;(
similar to the wolf/moose on Isle Royale)- yet the crop is t he final and complete victim.
B. Increase of pesticide is 30%, crop loss—unchanged
a. Crop Rotation would improve- yet not used as in pa$t .
5. New Pests
A. Allowed to ‘move in’- when nat. predators/consumer are removed
1. Persistent- years to break down, not dance
2. Bioaccumulation- stored in fat tissue
3. Biomagnification – increases in food chain (DDT / egg shells)
A. Problem- Mobility in the Environment
a. Water, wind- Mississippi R. ; east coast/Jet Stream
b. EWG- Environ. Working Group- private tests wells and air- found many mid-west
concerns; Calif. Air- many pesticides drifting from fields.
Risk of pesticides
1. Short term Effects
a. Most affected pop- farmers
b. Serious organophosphate poisoning- possible permanent damage to
nervous system and others.
c. Union Carbide overseas production of pesticide
2. Bhopal
a. 1984, Union Carbide release 40 tons of MIC for carbamate pesticides
exposing 600,000- 3000 dead 3000 dead over time, 50-60,000 with severe
b. 1989- agreed to pay $470 mil $500. /person
c. 2004 testing of ground and waterpersistent
d. Formosa termite Florida=
3. Long term effects
a. Cancer of lymphatics- lymphoma
b. Banana and pineapple workers- sterility
c. 1984 Central Valley, CA- higher miscarriages
d. Children of agricultural workers- birth defects, stunted limbs, lower immune sys.
e. Rat study of rotenone- similar to Parkinson’s
1. Cultivation Methods to Control Pests
1. Interplant -mix of plants
2. Strip cutting- only one segment is harvested
3. Crop rotation- change yearly and allow
2. Biological Controls
a. import of natural predators------Cane Toad
b. concerns- control of unintended hosts- guam brown nake, red deer autrailia
3. Phermones  are natural attractors
A. Hormone—regulates growth and metamorphosis
B. MIMIC-=====a synthetic hormone which triggers molting process
C. Benefit/Risk- also affects beneficial insects
Reproductive Controls
A. Sterilization- of males by radiation
B. Problem- needs continual populations
C. California Med Fly- needed 400 million/week
Genetic Control
D. Plants- some are not affected by pests
E. Fungi and bacteria- adapt and evolve
F. GM- genetically modified
1. Bt (soil bacterium) also killed caterpillar population
Bt potential and problem
G. Natural pesticide - not as effective as chemical pesticide; was
used less
H. 1980’s – Bt evolved yet cotton crops lost; if Bt increased more
insect evolution will occur to render useless as a natural
I. Unintended GM risk
Cornell U- found monarch butterfly would be affected.
4. Quarantine- restriction
A. Problem- if in CA, product will be sell as exports due to Med Fly
5. Integrated Pest Management-IPM
A. combines- bio cultivation and pesticide management
B. IPM needed for  sustainable agriculture and farmer education
C. Cotton responds well to IPM yet- uses 1% of ag. Land and 50% of all insecticides!
Irradiating Foods- extends shelf life (Co60 gamma)
A. Concern- free radicals carcinogenic
A. 1954 Pesticide Chemicals Amendment allows acceptable and
unacc. levels of pesticides in food
B. Delaney Clause- no carcinogens in processed food yet ‘allows’ in raw
foods milk, meats, fish, poultry
A. Regulated pesticide – effectiveness and no disclosure the inert ingredients, yet were
originally listed as active ingredients
B. 200+ are known – hazards, 21 are known carcinogens
A. Established pesticide residue limits on raw and processed food
Manufacture and Use of Banned Pesticides
A. Cannot be used in America butOK OVERSEAS
B. Boomerang Effect Alar on imported grapes to Phila.
C. Unknown amount entering US
A. 2004 treaty to protect humans from 12 POPS-persistent organic pollutants
B. Countries are to- eliminate production and use of POPs
C. USA – did not ratify treaty
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