Concentrate Splash, a 25-Minute Drive, and Pinpoint Pupils
A technician is mixing a liquid organophosphate concentrate (signal word DANGER; "Fatal if absorbed through skin") for a perimeter treatment. He is wearing a long-sleeve cotton shirt, leather gloves, and safety glasses. A hose clamp fails and roughly 100 mL of concentrate splashes across his forearms and soaks the gloves. He rinses his hands at a garden hose for about 20 seconds, finishes the mix, and drives 25 minutes to the next account. On arrival he reports headache, sweating, blurred vision, nausea, and cramping; his pupils are pinpoint. There is no eyewash or clean water on the truck.
1. What is the immediate response, and which parts of the earlier handling made the exposure worse?
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Treat this as a probable organophosphate poisoning emergency:
- Stop work and move him to fresh air; get someone else to drive.
- Remove contaminated clothing - cut the leather gloves off rather than pulling them over the hands. Put the contaminated items in a bag.
- Wash skin with soap and water for at least 15 minutes; flush eyes for 15 minutes if any splash reached them.
- Call 911 and Poison Control (1-800-222-1222) and send the label and SDS with him. Tell the receiving facility it is an organophosphate - cholinergic signs can progress to respiratory failure.
- Do not induce vomiting. The exposure was dermal, and inducing vomiting after solvent-containing concentrate exposure adds aspiration risk; only do it under poison-control direction.
What made it worse:
- Leather and cotton are not chemical-resistant. Leather absorbs concentrate and holds it against the skin for the entire 25-minute drive - effectively continuous dermal exposure, the exact route the label warns about.
- A 20-second rinse is not decontamination. Soap and water for 15 minutes is the standard.
- No eyewash and no clean water on the truck - a basic requirement when handling a DANGER-signal concentrate.
2. How do you separate this from heat illness before deciding whether to send him home?
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Compare the two patterns:
| Sign | Heat exhaustion | OP poisoning |
|---|---|---|
| Pupils | normal or dilated | pinpoint (miosis) |
| Skin | cool, clammy, heavy sweating | sweating, but with salivation and tearing |
| Pulse | rapid, weak | slow |
| Other | dizziness, improves with shade and fluids | abdominal cramps, vomiting, diarrhea, muscle twitching, blurred vision; worsens with rest |
His pinpoint pupils plus salivation, vomiting, and cramping after handling an OP concentrate are not consistent with heat exhaustion. Send him to medical care - do not send him home to "sleep it off," because respiratory failure can develop over hours. Also tell the hospital the pesticide class: atropine is the antidote for OP poisoning, and pralidoxime (2-PAM) is used for organophosphates but not for carbamates - the class determines treatment.
3. What PPE and equipment should have been in place for handling the concentrate, and what has to change before the next mix?
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For handling the concentrate (subject to the label's own PPE section, which governs):
- Chemical-resistant gloves in the material the label specifies (typically nitrile, butyl, or barrier laminate) - never leather, never cotton.
- Long-sleeved shirt and long pants or a coverall, plus a chemical-resistant apron for mixing.
- Goggles or a face shield (safety glasses alone do not stop a splash from reaching the eyes).
- Rubber boots; keep the pant legs outside the boot.
- On the truck: a change of clothing, soap, at least 5 gallons of clean water, and an eyewash.
Before the next mix:
- Repair or replace the failed hose clamp and inspect the rest of the plumbing.
- Use a closed transfer system or position the container so the operator stays above and upwind of the pour point.
- Re-read the label's PPE and mixing sections and restock the truck to match.
- Report the incident and get the technician medical follow-up; a documented exposure goes in the incident file.