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Pesticide Poisoning Symptoms and Other Health Issues. Joanne Kick-Raack State Coordinator, Pesticide Education Programs The Ohio State University Extension. Acute or Chronic?. Acute Effects Immediate “poisoning” or harm Based on LD50 values Most sensitive route determines Signal Word.
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Pesticide Poisoning Symptoms and Other Health Issues Joanne Kick-Raack State Coordinator, Pesticide Education Programs The Ohio State University Extension
Acute or Chronic? • Acute Effects • Immediate “poisoning” or harm • Based on LD50 values • Most sensitive route determines Signal Word
Acute or Chronic Effects? • Chronic Effects • Long-term effects from small doses over time • Not necessarily on label • Some information on MSDS
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
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, REI’s and harvest intervals protect against acute and chronic effects
Material Safety Data Sheets (MSDS) • Provides information on chronic toxicity • Refers to the concentrate rather than dilute product
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
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
Cholinesterase cont’d • Moderately severe • Unable to walk • Chest discomfort and tightness • Pinpoint pupils • Muscle twitching • Involuntary urination and bowel movement • Severe • Incontinence, unconsciousness, seizures
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.
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,
Synthetic Pyrethroids • Examples: Baythroid, Pounce • Synthetic mimics of natural pyrethrins • Systemic toxicity by inhalation or skin absorption is low—few human poisonings • Dermal and respiratory irritation • Stinging, itching, tingling progressing to numbness
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
Fungicides • Most are unlikely to cause severe or frequent poisonings • Cause irritant injuries to skin and mucous membranes, dermal sensitization
Fungicides • Chlorothalonil’s (Daconil) potential to cause cancer is unclear • EBDC’s under FQPA review as group • Can degrade to ETU which can produce cancer in mice • However, do not appear to be carcinogenic
Herbicides • Many can irritate skin, eyes and respiratory track • Low systemic toxicity • Ex. Some Round-up calls for eye protection
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 lining—vomiting. • Both cause skin irritation and burning
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
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.
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.
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
Chronic Effects and Controversy • Cancer • Endocrine disruption • Infertility and sperm counts • Multiple chemical sensitivity
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
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 developed—very difficult
Organochlorines and Cancer • DDT/DDE, dieldrin, chlordane • Accumulate in fatty tissues • No conclusive evidence • Infertile alligators and reduced sperm counts
Multiple Chemical Sensitivity • More frequent in women • Very controversial whether it is really a disease
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.
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