The World Health Organization (WHO), which includes USA CDC/NIH and NIH for RDNA, classifies microorganisms by Risk Group. UMSL only has Risk Group 1 and Risk Group 2 microorganisms.
WHO Risk Group 1 microorganisms are no or low individual and community risk. A microorganism that is unlikely to cause human disease or animal disease.
WHO Risk Group 2 microorganisms are moderate individual risk, low community risk. A pathogen that can cause human or animal disease but is unlikely to be a serious hazard to laboratory workers, the community, livestock or the environment. Laboratory exposures may cause serious infection, but effective treatment and preventative measures are available and the risk of spread of infection is limited.
The American Biological Safety Association has a searchable risk group database for bacteria, fungi, viruses and parasites available on their website.
U.S. Department of Health and Human Services, Public Health Service Centers for Disease Control and Prevention and the National Institutes of Health published the Biosafety in Microbiological and Biomedical Laboratories 6th edition (BMBL). This document is "an advisory document recommending best practices for the safe conduct of work in biomedical and clinical laboratories from a biosafety perspective". The BMBL defines four biosafety levels. UMSL only has BSL-1 and BSL-2 agents. Biosafety level 1 (BSL-1) offers a "basic level of protection and is appropriate for agents that are not known to cause disease in normal, healthy humans. Biosafety level 2 (BSL-2) is appropriate for handling moderate-risk agents that cause human disease of varying severity by ingestion or through percutaneous or mucous membrane exposure". Properly handled, these organisms are safe to use in educational and research labs. Personnel must still be cautious because BSL-1 and BSL-2 organisms may be "opportunistic pathogens and may cause infection in the young, the aged, and immunodeficient or immunosuppressed individuals. Vaccine strains that have undergone multiple in vivo passages should not be considered avirulent simply because they are vaccine strains".
The National Institute of Health has Guidelines for Research Involving Recombinant or Synthetic Nucleic Acid Molecules.
The Guide defines recombinant and synthetic nucleic acid molecules as:
(i) molecules that a) are constructed by joining nucleic acid molecules and b) that can replicate in a living cell, i.e., recombinant nucleic acids;
(ii) nucleic acid molecules that are chemically or by other means synthesized or amplified, including those that are chemically or otherwise modified but can base pair with naturally occurring nucleic acid molecules, i.e., synthetic nucleic acids,or
(iii) molecules that result from the replication of those described in (i) or (ii) above.
Agents are classified into four Risk Groups (RGs) according to their relative pathogenicity for healthy adult humans. UMSL only has Risk groups 1 and 2. (1) Risk Group 1 (RG1) agents are not associated with disease in healthy adult humans. (2) Risk Group 2 (RG2) agents are associated with human disease which is rarely serious and for which preventive or therapeutic interventions are often available. A list of agents classified by risk group are available in Appendix B, Classification of Human Etiologic Agents on the Basis of Hazard.
Standard Microbiological Practices
Standard microbiological practices are the fundamental operations and procedures practiced by laboratories for achieving a basic level of containment. At BSL-2, special microbiological practices are added to the standard practices to increase the level of containment to protect lab personnel and the environment. The Biosafety in Microbiological and Biomedical Laboratories 6th edition (BMBL)
details the standard microbiological practices for each biosafety level with increasing containment measures as the agent risk level increases.
These practices include, but are not limited to:
- Controlling access to the laboratory
- Hand washing
- No eating, drinking, or applying cosmetics or contact lenses in the lab
- Exclusive use of mechanical pippets
- Safe handling and disposal of sharps
- Reducing splashes and aerosols
- Proper decontamination procedures
- Posting signage to indicate hazards
All procedures involving the manipulation of biosafety level 2 infectious materials, that may generate an aerosol, should be conducted within a Biosafety Cabinet (BSC) or other physical containment devices. There are three classes of BSC; Class I, Class II, and Class III. The Class I BSC provides protection to personnel and the environment by using HEPA filtered exhausted air. Room air entering a Class I BSC is not filtered and does not protect sterile cultures or other sterile materials manipulated within the BSC. The most common class of BSC at the University is the Class II BSC. This cabinet uses HEPA filtered air exhaust and HEPA filters to remove contaminants from the airstream into the BSC workspace. This adds the benefit of protecting sterile samples from room air contaminants. Class II BSC can be safely used for work with all of the BSL-1 and BSL-2 agents used at the University of Missouri-St, Louis. Class III BSC are for work with highly infectious microbiological agents not present at UMSL. Appendix A of the BMBL 6th Edition details Selection, Installation and Use of Biological Safety Cabinets.
All BSC at the University should be certified annually to ensure proper function and containment.
Common laboratory sharps are needles, scalpels, pipettes, and broken glassware. Engineering controls and work practice controls can reduce the risk of sharps injuries. Place used needles and syringes in a conveniently located puncture-resistant container used for sharps disposal. Personnel should never bend or recap needles or remove them from disposable syringes. Transport non-disposable sharps in a hard walled container to the processing area for decontamination, preferably by autoclaving. Broken glassware should only be manipulated indirectly by mechanical means such as a dustpan, tongs or forceps. Place broken glassware in a sturdy cardboard box lined with a regular trash bag. Label the box “Broken Glass Only”. Plastic ware may be a suitable substitute for glassware in some instances. Shattered plastics are also considered sharps and can be disposed of with broken glassware. If the sharp is contaminated with blood, it has to be managed in a sharps container labeled as a “Biohazard”.