Mixing Malathion in an Unventilated Garage
A technician for a small upstate firm mixes a 57% malathion emulsifiable concentrate in the garage bay of the company truck. The label calls for 2 fluid ounces per gallon, and he is preparing 3 gallons of finished spray. The garage door is closed because it is 40 degrees outside; there is a floor drain in the corner. He wears leather work gloves, safety glasses, and a respirator he found in the truck's glove box with a dusty cartridge. While pouring, he splashes about a pint onto the concrete, wipes it with paper towels, and throws the towels into the truck bed next to his lunch wrappers. He then eats a sandwich without washing his hands. Ninety minutes into the route he develops a headache, blurred vision, sweating, and nausea. He tells his supervisor he thinks he has the flu and wants to finish the route.
1. What should happen first for the technician's symptoms, and what makes this presentation concerning?
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Stop the route and treat this as a possible pesticide exposure, not influenza. Move him to fresh air, remove contaminated clothing, wash skin with soap and water, and flush eyes for at least 15 minutes if there was any eye contact. Do not let him drive himself. Call 911 or the Poison Control Center (1-800-222-1222) and have the product label and SDS ready; give nothing by mouth to a drowsy person and do not induce vomiting.
The presentation is concerning because malathion is an organophosphate: headache, blurred vision, sweating, nausea, and salivation are consistent with cholinergic overstimulation rather than a cold. Medical evaluation is needed, and a physician may consider cholinesterase testing. The employer should document the incident, preserve the mixing container and the clothing, and follow its illness/injury reporting obligations. Afterward, the firm should review why a technician felt he had to choose between finishing the route and reporting symptoms, because that pressure is itself a safety hazard.
2. Identify the personal protective equipment and work-practice failures in the mixing operation and state the corrections.
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Failures and corrections:
- Leather gloves: leather absorbs and holds concentrate against the skin. Use chemical-resistant gloves specified on the label (commonly nitrile) and replace when contaminated.
- Safety glasses alone are marginal for pouring concentrate; use chemical splash goggles or a face shield.
- The respirator is a serious problem: it must be NIOSH-approved for the hazard and appropriate to the label, the wearer must have a medical evaluation and annual fit test, and cartridges must be stored clean and sealed, not dusty in a glove box. Follow the label's respirator statement.
- Mixing in a closed garage with a floor drain invites inhalation exposure and a route to the environment. Mix outdoors or in a ventilated area with secondary containment, and block the drain.
- No eyewash or water supply nearby, and eating/drinking in the work area before washing hands.
- No spill kit, and contaminated paper towels stored beside food.
Correct with a written mixing SOP: dedicated mixing site, containment tray, correct PPE, handwashing before eating, and spill supplies in every vehicle.
3. Describe proper cleanup and disposal of the spilled pint of concentrate.
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Keep others out, ventilate the area, and put on the PPE the label requires. Do not hose the spill toward the floor drain or a storm sewer; that turns a small spill into an environmental release. Control the liquid with absorbent (commercial pads, clay, or sawdust), work from the outside inward, and pick up residue with non-sparking tools. Place the absorbent and contaminated wipes in a labeled, closed container - not in the truck bed beside food. Clean the floor with detergent and water, absorb the rinse water, and add it to the same container.
Check the label and SDS for disposal directions; do not put pesticide waste in a dumpster or sanitary sewer unless the label specifically allows it, and use a licensed hazardous-waste hauler where required. Report to the employer, document the quantity, product, and cleanup, and call the NYSDEC spill hotline if the material reached a drain, soil, or waterway or the quantity meets a reporting threshold. Restock the spill kit and retrain the crew.