Summary

Solvent- or tensioactive-based bacterial or enzymatic preparations for cleaning surfaces in industrial and insttitutional environments are now being marketed as substitutes for traditional degreasers and cleaners. Enzymatic preparations are also used in health care settings to clean surgical and diagnostic instruments. Aside from the safety data and technical specifications provided by manufacturers, occupational and environmental hygienists and physicians, as well as other occupational health and safety specialists, have only fragmentary data on the composition of such preparations. Moreover, these preparations are often advertised as ideal, green and non-toxic products. This monograph is meant to present a summary and critique of knowledge on the health, safety, environmental and technical aspects of biotechnological products in order to guide practitioners who must evaluate, recommend or use them. The methodology mainly consists in a scientific and technical literature review. The research also involves consultation of practitioners from various industries and observation of environments in which workers are exposed to such preparations.

Biofountains use aqueous preparations made from bacteria with low or no risk of infection (called Group 1). They are increasingly replacing traditional solvent-based fountains, particularly for mechanical maintenance. Eliminating solvents is beneficial from a safety and health perspective. Except for one case of respiratory sensitivity reported in the literature, no health effects have been demonstrated after biofountain usage. They are also safer for the environment because the bacteria transform a large part of the organic contaminants (oils, greases) into water and carbon dioxide. However, some studies indicate the presence of bacteria presenting a moderate risk of infection for individuals using biofountains (called Group 2). Users are advised to protect their skin (gloves, long-sleeved clothing) and eyes (safety goggles) and follow individual hygiene measures. Aerosols may be generated when blowers are used to dry the cleaned parts. As there is no data on this type of inhalation exposure, users are advised to rinse the parts with water before drying or to wear an N-95 filtering face-piece respirator (FFR) (disposable mask). This research also documented the use of spray-applied bacterial preparations. In the absence of metrological data, wearing an N-95 face-piece respirator (disposable mask) is recommended in these conditions.

Enzyme-based detergents are widely used in the health care industry to clean surgical and diagnostic instruments. The literature reports several cases of respiratory sensitivity in workers handling subtilisin-based detergents, subtilisin being the best-documented enzyme in this context and the only one subject to an exposure limit value in Québec. There is still very little data on levels of exposure to subtilisin or other enzymes in these environments, although aerosols may be present, particularly when blowers are used to dry instruments. Pending better documentation of exposure levels, if aerosols are suspected to be present and there is no laboratory hood, particularly during manual washing of instruments, it seems advisable to recommend wearing a face-piece respirator (disposable mask) rather than a simple surgical mask. In addition, to protect against potential splashes, the respirator should be resistant to liquid projections. Wearing gloves, a long-sleeved smock, eye protection, cap and shoe covers is also recommended. 

This work also documented other uses of bacterial or enzymatic preparations, particularly for institutional housekeeping and in the food industry. There is very insufficient documentation on the composition of products like this, their uses, occupational exposures and potential health effects.

Concerning bacterial cleaners more specifically, it should be noted that they may be voluntarily certified with an environmental label in accordance with EcoLogo Standard CCD-110, which ensures that they comply with environmental protection criteria, contain no pathogenic micro-organismes and are technically efficient. In a context where the regulatory framework for use of micro-organisms in the workplace is insufficient, the application of this standard should be encouraged.

In conclusion, bacterial and enzymatic cleaners and degreasers are increasingly prominent on the market. Although, overall, few workplace health effects have been reported following their use, there are risks and various individual protection measures are recommended depending on the circumstances. Metrological studies should be done to document the nature and levels of bacteria and enzyme exposure in conditions most likely to generate aerosols. Considering the exploratory nature of field data in this research, a mapping should also be done on the use of such products in Québec workplaces.