The disinfectant properties of hydrogen peroxide make it an element frequently used in the medical field and the pharmaceutical industry. Oxygenated water makes it possible to meet the sterilization needs of reusable instruments and the need for bio-decontamination of research and drug production laboratories. However, the use of this chemical element involves certain dangers and requires the use of gas detection and respiratory protection equipment.
Disinfection and bio-decontamination with hydrogen peroxide
Hydrogen peroxide in the medical environment
Providing care, preventing infections and preventing cross-contamination, the care equipment sterilization is essential in the medical world. The disinfection of reusable medical equipment is carried out with water vapor or hydrogen peroxide. The H2O2 technique is mainly used when the use of an autoclave (hermetic pressurized chamber with water vapor) at high temperature is likely to damage the material to be sterilized such as plastic or even certain complex or fragile medical tools. Thus hydrogen peroxide disinfection is applied, for example, to catheters, endoscopes, or even surgical instruments.
The hydrogen peroxide sterilization technique is performed cold and at low pressure by exposing medical equipment to this gas. A hydrogen peroxide plasma sterilizer can destroy infectious agents on medical instruments quickly and easily (approximately 1 to 2 hours depending on the equipment). The to be disinfected instruments are placed in a vacuum chamber and then subjected to vaporized or gaseous H2O2. A plasma phase of hydrogen peroxide, generated by an electromagnetic field, follows. It is during this phase that the bacterial cells’ destruction and the complete instruments’ sterilization take place. After ventilation, the chamber can finally be opened and the sterilized tools can be reused.
Hydrogen peroxide in the pharmaceutical industry
The use of H2O2 for bio-decontamination is also used in the pharmaceutical industry. In fact, in many pharmaceutical applications (research, manufacturing, monitoring, etc.) controlling contamination risks is a major issue. These activities, such as the manufacture of sterile drug medicines for example, require places classified as clean zones according to the ISO 14644 standard. The pharmaceutical industry therefore operates controlled atmosphere zones (CAZ) requiring control of microbial contamination risks as well as bio-decontamination processes. These controlled atmosphere zones include, for example, drug manufacturing workshops, stability chambers, clean rooms, transfer rooms, isolators and even certain warehouses.
The principle of gas disinfection has been known since ancient times (sulfur, arsenic, hydrochloric acid), and after having exploited various gases such as ethylene oxide (ETO) or formaldehyde, today the pharmaceutical industry favors hydrogen peroxide for the bio-decontamination processes of clean areas.
Sterilization of clean rooms is carried out by hydrogen peroxide fumigation, by H2O2 vaporization, or by dispersing an H2O2 solution in aerosol droplets. Treatment of a room by automatic disinfection machines destroys all strains of microbial and bacterial contamination present in a room and thus decontaminates the entire environment. Airborne decontamination processes rely on high concentrations of hydrogen peroxide (up to 35%) in a room and must be carried out in a closed area without any present personnel.
The H2O2 danger in the medical and pharmaceutical industries
Hydrogen peroxide properties
Hydrogen peroxide – CAS 7722-84-1 – also known as oxygenated water, is commonly used in medical environments and in the pharmaceutical industry. H2O2 is a toxic, corrosive and oxidizing element. It is particularly its corrosive and toxic properties that make it an excellent biocide used for sterilization and bio-decontamination. Hydrogen peroxide is indeed exploited for these properties in the medical and pharmaceutical industries, but also in the food industry (packaging sterilization), water treatment, or even in stationery (paper pulp bleaching). French health authorities fixed a 1ppm OELP (8-hour occupational exposure limit value) in order to protect workers from these dangerous gas properties.
H2O2 dangers in bio-decontamination
The use of hydrogen peroxide in the medical world and in the pharmaceutical industry represents a danger to the many professionals working in these environments. Indeed, the use of H2O2 as a sterilization and bio-decontamination agent can involve acute chronic or accidental exposure to dangerous concentrations of this gas. Malfunction or improper use of machines, non-compliance with safety procedures or even improper H2O2 solutions handling entails a gas leak risk and dangerous health effects on people.
Chronic exposure to low concentrations of H2O2 will cause skin irritation, hair bleaching and respiratory tract irritation. Exposure to high concentrations can cause significant hydrogen peroxide vapors inhalation and can result in severe respiratory distress, unconsciousness or fatal systemic poisoning.
Protection equipment for H2O2 bio-decontamination
Hydrogen peroxide detectors for disinfection
To face hydrogen peroxide dangers, safety measures must be implemented in medical and pharmaceutical circles exploiting this gas.
Among these safety measures, gas detection and monitoring is an essential element. Different measurement solutions are used for this:
- The portable H2O2 detector: mobile and practical, a portable hydrogen peroxide detector like the X-am 5100 immediately alerts its wearer in case of danger. The Portasens III detector fitted with its sampling probe and interchangeable sensors will allow ultra-precise concentration measurement as well as leaks localization on sterilization equipment.
- The fixed hydrogen peroxide detector: ideal for the control of bio-decontamination processes in the pharmaceutical industry, a fixed B12 detector installed in the treated room connected to a gas controller outside guarantees continuous gas concentration monitoring.
- Colorimetric reagent tubes: inexpensive and easy to use, they allow rapid measurement of concentrations after a decontamination process, for clearance before entering a treated room.
Respiratory protective equipment for bio-decontamination
In addition to the detection equipment, if personnel must intervene in a high hydrogen peroxide concentration environment, it is imperative that they are equipped with respiratory protection equipment. This equipment is used based on exposure situations:
- For work situations, a supplied air respirator system must be used to ensure a constant flow of healthy breathing air to staff operating in these environments.
- For emergency situations in presence of H2O2, responders should wear self-contained breathing apparatus (SCBA).
- Finally, insulating emergency escape breathing devices equipment – self-rescuer masks more precisely – must be made available in at risk places.