Biohazard testing

From the above considerations it should be clear that there are situations in which one must rely on data generated in nonhuman systems to assess the hazard to humans of certain chronic chemical exposures. In the preceeding sections a sampling of the more commonly used assays which have been developed for this purpose have been described. What remains to be discussed are the factors which influence the interpretation and applicability of the rodent and short-term biohazard test data humans. 

Parts 58.41 through 58.51 cover the physical facihties of the laboratory. The inspector must determine whether or not the facilities are of adequate size and design for completed or in-process studies. The physical parameters and systems of the facilities as they are used to accommodate the various operations employed in the GLP studies are examined. Investigators also deal explicitly with the environmental control and monitoring procedures for critical areas, especially the rooms used for animal housing, the test article storage areas, and the laboratory areas in which biohazardous material is handled. The procedures and methods for cleaning equipment and areas critical to study conduct as well as the cur-... 

Does the facility have a number of rooms separate from those above to ensure isolation of studies being done with test systems or test and control articles known to be biohazardous including materials and infectious agents ... 

The test facility should have a sufficient number of rooms or areas to assure the isolation of test systems and the isolation of individual projects, involving substances or organisms known to be or suspected of being biohazardous. 

In addition to serologic testing, diagnosis should be pursued by microbiologic culture of blood or body fluid samples. Cultures should be held for at least 2 months, with weekly subcultures onto solid medium. Because it is extremely infectious for laboratory workers, the organism should be subcultured only in a biohazard hood. The reported frequency of isolation from blood varies widely, from less than 10% to 90% B melitensis is said to be more readily cultured than B abortus. Culture of bone marrow may increase the yield.46... 

As published in the Journal of Membrane Science 279 (2006) Dr Frey has successfully prepared nanofibre substrates for biosensors based on biotin-streptavidin specific binding. When it is eventually produced, testing a surface for biohazards such as E coli could be as simple as giving it a wipe. 

Using the spatula, fill each of the two vials about half full with the unknown powder. Replace the caps and seal the vials with biohazard tape. Preserve one vial as evidence and the other for confirmatory tests. 

During the preparation of hazardous drugs, use a ventilated cabinet to reduce the potential for occupational exposure. Performance test methods and criteria for BSCs may be found in Primary Containment for Biohazards Selection, Installation and Use of Biological Safety Cabinets, second edition, CDC/NIH, 2000. A current field certification label should be prominently displayed on the ventilated cabinet per NSF/ANSI49. 

All work with test and control chemicals should be conducted under Class II, Type II biohazard hoods (or equivalent) that are vented directly to the outside. Several types of filter systems can be used to prefilter the exhaust air, including HEPA and activated charcoal. Precise measurements of the efficiency of such filter systems, however, have not been reported. 

As summarized in Table 1, aqueous extracts ( leachates ) can be prepared with various materials, largely to mimic the environmental fate of the potential mutagens contained in the solid or semisolid materials. For example, aqueous extracts of solid industrial wastes can be prepared and subjected to mutagenicity testing in an attempt to monitor biohazards. Similarly, fly ash from coal-fired power plantscan be extracted with horse serum for determination of mutagenic activity. Obviously, most of the problems pointed out with organic extracts are also inherent in aqueous extracts. The presence of histidine can also affect the results of the Salmonella histidine-reversion assay. 

J. L. Epler, F. W. Larimer, T. K. Rao, C. E. Nix, and T. Ho, Energy-related pollutants in the environment The use of short-term tests for mutagenicity in the isolation and identification of biohazards. Presented at Higher Plant Systems as Monitors of Environmental Mutagens, a workshop co-sponsored by the National Institute of Environmental Health Sciences and the Department of Energy, Marineland, Florida, January 16-18, 1978, Environ. Health Perspect. 27, 11-20 (1978). 

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