H2O2’s overblown safety claims are dangerous

All chemicals capable of achieving terminal sterility are inherently dangerous requiring exposure monitoring, training and engineered redundancies designed to offer the highest level of operator protection. Claiming your sterilant is “safe” and “non-toxic” does a serious disservice to users who may, then, not treat the sterilant with the respect it deserves. Our aim in this post is not to compare H₂O₂ and EO (both are potentially dangerous and must be used with care). Instead, we hope to demonstrate widespread instances of operator injury in hopes of encouraging fair comparison and careful use.

INTRODUCTION

The FDA’s adverse events (or, “MAUDE”) database was reviewed to identify medical device reports submitted during the past five years that involve use of a low-temperature system or process labeled to sterilize various types of heat- and moisture-sensitive reusable medical instruments used in the healthcare setting.

This review focused on reports satisfying the following two criteria: the process uses hydrogen peroxide (H₂O₂) as a vapor or gas plasma to achieve sterilization; and the FDA report described actual or potential harm to healthcare workers.

METHODS & OBJECTIVES

This review aimed to provide perspective and context when comparing the safety of H₂O₂-based systems to alternative low-temperature systems labeled to achieve instrument sterilization. The reviewed adverse event reports were obtained by searching the MAUDE database using the product code “MLR,” which FDA uses to classify processes or systems that use a chemical to achieve sterilization.

This review was limited to evaluating employee safety, not patient safety per se. Low-temperature sterilization systems using a chemical agent other than H₂O₂ to achieve sterilization were excluded from this analysis. This review’s definition of “harm” is broad and is not intended to necessarily imply a healthcare worker was permanently injured. Harm in this context also includes transient self-healing skin reactions, for example. 

RESULTS

Several reports were identified describing actual or potential harm to healthcare employees associated with use of H₂O₂-based low-temperature sterilization systems. These cases include reports describing skin burns, respiratory complaints, headaches and eye irritation, among other types of harms.

Not every identified case reported that medical treatment was necessarily required, sought and/or administered, although this review could not independently verify this claim or any other findings, assertions or claims provided in the reports.

The following list provides a random sample of several of the FDA reports that this review identified. The text of each of these listed reports is abbreviated. For completeness and context, the report should be read in its entirety. These reports were not limited to any one specific manufacturer or H₂O₂-based sterilization system.

1. Skin irritation, burns

• An employee’s fingers were burned while handling items processed in the sterilizer.
• A healthcare worker received a “’chemical burn’ or skin reaction” when removing two instrument loads from the sterilizer and handling a new sterilant cassette.
• Two employees experienced burns on their hands while handling items processed in the sterilizer.
• The sterilizer emitted an “’odor’ or smell.” Two healthcare workers reported experiencing throat discomfort and skin irritation.
• The sterilizer emitted a “strong odor.” A healthcare worker experienced “a skin reaction related to the odor and reported itching on her face” when she opened the sterilizer’s door to remove the processed load.

2. Respiratory complaints

• The sterilizer was emitting an “’odor’ or smell.” Two healthcare workers experienced reactions: one “felt sensitivity and experienced a headache,” and the other “experienced shortness of breath and dizziness.”
• The sterilizer was emitting a “’smoke’ or oil mist” that had been occurring for several weeks. Six healthcare workers reported “eye, nose, and throat irritation, burning mouth and lips, headache, earache, and fatigue related to the smoke/oil mist.”
• The sterilizer had been emitting an odorless “mist” or haze for approximately two days. Two healthcare workers experienced nausea, throat irritation, coughing, headache and cold hands. One healthcare worker with a history of asthma reported respiratory symptoms, but these were reportedly resolved by the worker’s use of an asthma inhaler. This worker also reported a very slight “nose bleed.”
• The sterilizer was emitting “smoke.” Several healthcare workers experienced a “reaction.” One worker experienced “tingling” in her nose and throat and reported that she felt like she “needs to clear her throat constant (sic) for the last 10 minutes.”

3. Neurological symptoms

• The sterilizer was emitting “fumes” or an odor. Two male healthcare workers experienced headaches.
• Two healthcare workers reportedly experienced “respiratory and neurological reactions while working around” the sterilizer, which was emitting a “harsh odor” and had been blowing air from the chamber for three months. One of these workers experienced symptoms of headaches, cough, persistent throat irritation and a “bitter taste in the mouth and hoarseness in her voice” when she inhaled the “fumes.”
• The sterilizer had emitted “’intermittent fog’ or a haze/mist.” Two healthcare workers experienced itchiness in the nose, throat discomfort, “burning when inhale,” and a “soft headache.”
• The sterilizer was emitting an “odor” or smell while operating. One healthcare worker experienced a “headache and red blotches/hives on both arms and back and complained of a little forehead swelling too.” The worker was treated with a steroid injection, tetanus shot and was prescribed a “Z-Pak.” The worker reported that her response might have been “an allergic reaction” to the sterilizer’ vapor.
• A sterilizer was emitting smoke and a “strong chemical odor.” Two healthcare workers experienced “eye irritation and ‘slight burning’, headache, and nausea.” The report additionally states that the healthcare workers also experienced “neurological and gastro-intestinal symptoms” (that apparently resolved without medical treatment).

4. Eye irritation

• “Smoke” emitted from the sterilizer reportedly caused an employee to experience “eye irritation” and seek medical treatment.
• An “odorless vapor/smoke” emitted from the sterilizer reportedly caused a healthcare worker to experience “irritation, burning, and itchiness in the eye.”
• The report states that the sterilizer was emitting an odor and haze. One healthcare worker reported experiencing “burning eyes, sore throat and itchy skin” related to this odor and haze. The worker reported that his symptoms lasted for two hours after exposure.
• “Steam” or haze emitted from the sterilizer reportedly caused 10 healthcare workers to experience eye irritation and “scratchy throats.”
• The sterilizer was emitting an “odor and haze” with a “bad smell” and containing hydrogen peroxide “residuals.” Multiple healthcare workers also complained of throat and eye irritation, and one worker complained of a “skin irritation” while handing one of the sterilizer’s processed loads.

5. Nausea, dizziness

• An employee experienced eye irritation and dizziness while operating the sterilizer.
• Two employee experienced dizziness and eye irritation while in the room with the sterilizer.
• The sterilizer was emitting an “oily smell” or odor. One healthcare worker reported experiencing nausea, and an unconfirmed number of workers experienced headaches.
• A sterilizer was emitting a “fluid leak and haze.” Two healthcare workers experienced a “headache and dizziness.”

6. Flames and/or fire department dispatched

• The sterilizer “caught fire. The floor was evacuated, and the fire department was dispatched. The fire department extinguished the flames.”
• The facility’s personnel “noticed a burning smell and observed flames coming from the (sterilizer).” An employee extinguished the fire.
• A healthcare worker experienced throat irritation and “hives” related to a “mist/haze” emitted from the sterilizer. The fire department was called in response to the mist, at first thought to be smoke, in the sterile processing room. The report states that the worker had two spots on her neck that she described as “small water blisters,” which she believes were in areas exposed to the mist. The worker went to the emergency room for treatment.