Exposure is potentially lethal – do you know how to respond?
Phosphine and sulfuryl fluoride are the two main fumigants used in the grain industry to control insect populations. Both are restricted-use pesticides not available to the general public and are only available to licensed dealers/distributors and certified applicators.
As a gas, phosphine and sulfuryl fluoride have a high acute (short term) inhalation toxicity, but exposure can occur through various methods. Acute effects of exposure are most often the result of misuse, including application inconsistent with the product labeling. Knowing the appropriate first aid treatment is important when exposure to a fumigant occurs.
Health Hazard
Both phosphine and sulfuryl fluoride have a high health hazard as indicated by the “4” in the blue box on the NFPA hazard diamond, which indicates that they can be lethal (see Figures 1 and 2 on p. 65). A very short exposure to either chemical could cause death or major residual injury.
Symptoms such as headache, dizziness, nausea, difficulty breathing, abdominal pain, vomiting, diarrhea, slowing of movements and speech, and numbness in extremities may indicate exposure. If any of these symptoms occur, take the person to a doctor or emergency treatment facility.
Exposure
There are three main entry routes of exposure to insecticides into the body (see Figure 3 on p. 66):
• Respiratory by inhalation into the lungs.
• Dermal by exposure through the skin or eyes.
• Oral through ingestion by mouth.
If exposure occurs, contact a doctor or poison control center for treatment advice, and have the product container, label, and applicator’s manual available when calling or going for treatment.
Respiratory Exposure
If a fumigation gas is inhaled, move the person as quickly as possible to fresh air. If the person has stopped breathing, call an emergency responder or an ambulance, and then give the person artificial respiration. Having one or more persons trained in CPR is a good practice for your business or company.
To prevent inhalation of phosphine gas, always use an appropriate respirator or SCBA (self-contained breathing apparatus), or have the proper personal protective equipment available on-site for use in case of a gas release. For sulfuryl fluoride, you can only use a positive pressure self-contained breathing apparatus (SCBA) or combination air-supplied/SCBA because no respirators are available for this product.
Dermal Exposure
When a fumigant gets on the skin, rinse the area immediately with plenty of water for 15-20 minutes. Be careful, because unwashed hands can cross-contaminate other parts of the body.
If a phosphine product gets on clothing, take off the contaminated clothing immediately and allow the clothes to aerate in a well-ventilated area prior to laundering.
If sulfuryl fluoride contacts unprotected skin during introduction into a structure, it may cause frostbite. If it contaminates clothing, apply water to the clothing before removing. After the clothing has thawed, remove all clothing, shoes, and other items covering the skin, and then immediately rinse the skin with water for 15-20 minutes.
Eyes are extremely absorptive. If the product enters the eyes, hold the eyes open and rinse slowly and gently with cool water for 15-20 minutes. If the person is wearing contact lenses, rinse the eyes with the contacts in place for the first five minutes, then remove the contact lenses and continue rinsing the eyes.
To minimize dermal exposure, wear appropriate clothing and/or face protection as indicated on the label.
Oral Exposure
Of the fumigant products available, it is more likely to ingest a solid formulation of phosphine, such as pellets or tablets, than a gaseous phosphine product or sulfuryl fluoride since it is only available in a gaseous form. If a phosphine product is swallowed, have the person sip a glass of water if they can swallow it. Do not induce vomiting unless told to do so by a doctor or poison control center. Never give anything by mouth to a person who is unconscious.
To prevent accidental ingestions, avoid eating, drinking, or using tobacco products until thoroughly washing your hands. Always keep insecticides in their original containers – never transfer them into food or drink containers. Never reuse an insecticide container for another purpose, such as an aluminum phosphine flask for a water bottle.
Summary
Applying fumigants to protect stored products from insects is an important part of an integrated pest management strategy. However, when fumigating, exposure may occur. Being prepared to handle exposure is critical to keeping everyone safe during a fumigation.
Edmond Bonjour is an Associate Extension Specialist – Stored Products Entomologist in the Department of Entomology and Plant Pathology at Oklahoma State University, Stillwater. He can be reached at 405-744-8134 or edmond.bonjour@okstate.edu.