1. Paraquat Toxicity and Treatment

2. Paraquat Skin: Nails: Respiratory Eyes: Ingestion:
Paraquat: is very toxic to the skin and mucous membranes (inside of mouth, nose, eyes). Particles are considered too large for respiratory absorption, but once paraquat in the system (through broken skin or mucous membranes) it migrates to the lungs because of its oxygen seeking properties. If ingested it is very lethal, survival rates are generally poor.
Skin:
dryness, cracks
erythema (redness)
blistering
ulcerations
Nails:
discoloration
splitting nails
loss of nails
Respiratory
cough
nosebleeds
sore throat
Eyes:
conjunctivitis (irritation)
ulceration, scarring, blindness
Ingestion:
pulmonary fibrosis
multi-system organ failure, specifically
respiratory failure
kidney failure

3. Toxicology
Ingestion- life threatening effects on GI, kidney, liver and heart
LD50 3-5mg/kg or 10-15ml in 20% solution
Most lethal in lungs – but toxicity from inhalation rare
Mechanism – generation of free radicals with oxidative damage to lung tissue
Pulmonary fibrosis w/in 7-10 day causes death

4. Source: Richards, Kerry Penn State University Extension Service

5. LD50
Lethal Dose = Amount of chemical it takes to kill 50% of an experimental population

6. Source: Richards, Kerry Penn State University Extension Service

7. Source: Richards, Kerry Penn State University Extension Service

8. Adverse effects of Exposure
GI: mucous membrane swelling, edema, ulcerations
Renal –proximal renal tubule damage –reversible
Cardiac – focal necrosis myocardium
Cerebral – edema and brain damage
Smoking paraquat contaminated marijuana: pyrolyzed to non toxic dipyridyl

9. Toxicology (Skin) Local skin damage  contact dermatitis
Prolonged contact  blisters, abrasion, ulcerations, finger nail changes
Slow absorption via intact skin
Abraded or eroded skin absorption efficient

10. Treatment of Contact Dermatitis from Paraquat
Upon contact, flush the skin with copious amounts of water
Mild skin reactions are usually self limiting as long as there is no more contact
More severe reaction should be treated by a dermatologist

11. Factors Leading to Illness Event
What the product used for its intended purpose?
Is it registered?
Is it registered for use on wheat & alfalfa?
Is it restricted?
What the product used correctly?
What factors could have lead the worker not to take action to mitigate the effects?