Pesticide Poisoning Pesticide Poisoning Symptoms and Other Health Symptoms and Other Health

IssuesIssues

Joanne Kick-Raack

State Coordinator, Pesticide Education Programs

The Ohio State University Extension

Acute or Chronic?Acute or Chronic?

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

Acute or Chronic Effects?Acute or Chronic Effects?

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

Chronic EffectsChronic 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 HealthThe 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 Material Safety Data Sheets (MSDS)(MSDS)

Provides information on chronic toxicityRefers to the concentrate rather than dilute

product

Organophosphates and Organophosphates and CarbamatesCarbamates

Examples: Lorsban, Diazinon, Sevin, Malathion, Furadan and many others

Cause of most acute pesticide poisoningsInhibit cholinesterase, affect the nervous

systemEffect is reversibleMonitor with blood tests

Signs and Sypmtoms of Signs and Sypmtoms of Cholinesterase InhibitionCholinesterase 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’dCholinesterase 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 Aggregate and Cumulative ExposureExposure

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 Natural Pyrethrum/Pyrethrins and Rotenoneand Rotenone

Crude pyrethrum is a dermal and respiratory irritant

Asthma has occurred after exposuresRefined pyrethrins less allergenic but some

irritant and sensitizing propertiesRotenone has little human hazard

– Hazardous to fish, birds,

Synthetic PyrethroidsSynthetic Pyrethroids

Examples: Baythroid, PounceSynthetic mimics of natural pyrethrinsSystemic toxicity by inhalation or skin

absorption is low—few human poisoningsDermal and respiratory irritation

– Stinging, itching, tingling progressing to numbness

Natural Inorganic InsecticidesNatural 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

FungicidesFungicides

Most are unlikely to cause severe or frequent poisonings

Cause irritant injuries to skin and mucous membranes, dermal sensitization

FungicidesFungicides

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

HerbicidesHerbicides

Many can irritate skin, eyes and respiratory track

Low systemic toxicityEx. Some Round-up calls for eye protection

Diquat/ParaquatDiquat/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 MCPA2,4-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 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 Cancer2,4-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 CancerAtrazine and Cancer

Found in drinking waterUnder 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 Chronic Effects and ControversyControversy

CancerEndocrine disruption

– Infertility and sperm counts

Multiple chemical sensitivity

Food Quality Protection ActFood 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 disruptionHigher protection factor for children

Endocrine DisruptionEndocrine 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 CancerOrganochlorines and Cancer

DDT/DDE, dieldrin, chlordaneAccumulate in fatty tissuesNo conclusive evidenceInfertile alligators and reduced sperm

counts

Multiple Chemical SensitivityMultiple Chemical Sensitivity

More frequent in womenVery controversial whether it is really a

disease

Agricultural Health StudyAgricultural 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 InformationToxicity 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