Pesticide Poisoning Symptoms and Other Health Issues

1
Pesticide Poisoning Symptoms and Other Health
Issues

• Joanne Kick-Raack
• State Coordinator, Pesticide Education Programs
• The Ohio State University Extension

2
Acute or Chronic?

• Acute Effects
• Immediate poisoning or harm
• Based on LD50 values
• Most sensitive route determines Signal Word

3
(No Transcript)
4
(No Transcript)
5
(No Transcript)
6
(No Transcript)
7
(No Transcript)
8
(No Transcript)
9
Acute or Chronic Effects?

• Chronic Effects
• Long-term effects from small doses over time
• Not necessarily on label
• Some information on MSDS

10
Chronic Effects

• Carcinogenicity-cancer
• Mutagenicity-genetic changes
• Teratogenicity- birth defects
• Oncogenicity-tumor growth (not necessarily
  cancers)
• Liver damage
• Reproductive disorders-sperm count, sterility,
  miscarriage
• Nerve damage
• Allergenic sensitization

11
The Label and Your Health

• Signal word based on the LD50 of the most toxic
  route of exposure
• Statement of Practical Treatment is first aid
• Signal word does not indicate chronic toxicity
• Product can be restricted use for oncogenicity
  although the signal word is Caution
• Protective equipment, REIs and harvest intervals
  protect against acute and chronic effects

12
(No Transcript)
13
Material Safety Data Sheets (MSDS)

• Provides information on chronic toxicity
• Refers to the concentrate rather than dilute
  product

14
Organophosphates and Carbamates

• Examples Lorsban, Diazinon, Sevin, Malathion,
  Furadan and many others
• Cause of most acute pesticide poisonings
• Inhibit cholinesterase, affect the nervous system
• Effect is reversible
• Monitor with blood tests

15
Signs and Sypmtoms of Cholinesterase Inhibition

• Can be confused with flu, or heat exhaustion
• Mild poisoning symptoms
• Headache, fatigue, dizziness, loss of appetite,
  nausea, cramps, diarrhea
• Blurred vision, excessive tearing
• Contracted pupils
• Excessive sweating and salivation (this is not
  true for heat stress)
• Slowed heartbeat
• Rippling of muscles underneath skin

16
Cholinesterase contd

• Moderately severe
• Unable to walk
• Chest discomfort and tightness
• Pinpoint pupils
• Muscle twitching
• Involuntary urination and bowel movement
• Severe
• Incontinence, unconsciousness, seizures

17
Aggregate and Cumulative Exposure

• Food Quality Protection Act in reexamining
  pesticides EPA adds all exposures from all
  pesticides in a group (ex.organophosphates)
  together to estimate public health risks.

18
Natural Pyrethrum/Pyrethrins and Rotenone

• Crude pyrethrum is a dermal and respiratory
  irritant
• Asthma has occurred after exposures
• Refined pyrethrins less allergenic but some
  irritant and sensitizing properties
• Rotenone has little human hazard
• Hazardous to fish, birds,

19
Synthetic Pyrethroids

• Examples Baythroid, Pounce
• Synthetic mimics of natural pyrethrins
• Systemic toxicity by inhalation or skin
  absorption is lowfew human poisonings
• Dermal and respiratory irritation
• Stinging, itching, tingling progressing to
  numbness

20
(No Transcript)
21
Natural Inorganic Insecticides

• Boric Acid and Borates
• Irritating to skin
• Infants- boiled lobster appearance redness,
  followed by peeling of skin
• Sulfur
• Dermatitis-skin irritation
• Irritation of eyes and respiratory tract

22
Fungicides

• Most are unlikely to cause severe or frequent
  poisonings
• Cause irritant injuries to skin and mucous
  membranes, dermal sensitization

23
Fungicides

• Chlorothalonils (Daconil) potential to cause
  cancer is unclear
• EBDCs under FQPA review as group
• Can degrade to ETU which can produce cancer in
  mice
• However, do not appear to be carcinogenic

24
Herbicides

• Many can irritate skin, eyes and respiratory
  track
• Low systemic toxicity
• Ex. Some Round-up calls for eye protection

25
Diquat/Paraquat

• Paraquat more toxic (orally)
• Large doses (6-8oz.) produces fatal lung changes.
• Fluid accumulation in lungs can occur in 24 to 72
  hrs. Respiratory failure.
• Exposure may cause blackening and abnormal growth
  of nails
• Diquat affects eye lens and intestinal tract
  liningvomiting.
• Both cause skin irritation and burning

26
2,4-D and MCPA

• Moderately irritating to skin and mucous
  membranes
• May cause burning sensations in nose, sinuses and
  chest, dizziness
• Not agent orange
• Agent orange issue was from dioxin contaminant in
  the manufacture of 2,4,5-T

27
2,4-D and Cancer

• There are no reports that indicate a direct link
  between 2,4-D exposure and cancer in humans.
• Some concern about higher rates of a type of
  cancer, non-Hodgkins lymphoma, among farmers, ag
  workers and pesticide applicators but different
  studies are not consistent.

28
2,4-D and Cancer

• Most studies have not found a relationship
  between exposure to chlorophenoxy herbicides and
  soft sarcoma.
• Current evidence does not indicate that exposures
  to 2,4-D are linked with an increased incidence
  of breast cancer in humans or experimental
  animals.

29
Atrazine and Cancer

• Found in drinking water
• Under special review
• Based on scientific evidence presented, EPA
  reclassified atrazine as not likely to be a
  human carcinogen
• Will be evaluating endocrine disruption

30
Chronic Effects and Controversy

• Cancer
• Endocrine disruption
• Infertility and sperm counts
• Multiple chemical sensitivity

31
Food Quality Protection Act

• All older pesticides must be reevaluated based on
  new standards
• Evaluating risk based on cumulative and aggregate
  exposure
• New testing for endocrine disruption
• Higher protection factor for children

32
Endocrine Disruption

• Hormones, alter bodily functions, development,
  and growth
• We are only starting to gather information on
  which chemicals are endocrine disruptors and at
  what level they have an effect.
• FQPA mandates testing of pesticides for endocrine
  disruption
• New screening tests must be developedvery
  difficult

33
Organochlorines and Cancer

• DDT/DDE, dieldrin, chlordane
• Accumulate in fatty tissues
• No conclusive evidence
• Infertile alligators and reduced sperm counts

34
Multiple Chemical Sensitivity

• More frequent in women
• Very controversial whether it is really a disease

35
Agricultural Health Study

• www.aghealth.org
• National Cancer Institute
• Iowa and North Carolina
• Long-term study, collecting wide range of
  information
• Evaluate the incidence of many types of cancer
  and chronic diseases in relation to exposure to a
  variety of chemicals used on the farm in both
  women and men.

36
Toxicity Information

• National Pesticide Telecommunication
  Network 800-858-7378
• Extoxnet ace.orst.edu/info/extoxnet/
• Poison Control Centers
• Ohio State University Extension, Pesticide
  Education Program pested.osu.edu