Aerosols Containing Microorganisms

In a series of investigations based on the pyrolysis of bacteria with vapor characterizations by GC-DMS, mobility methods were developed that could provide at 

FIGURE 17.1 Ion mobility results were obtained rapidly from patches placed on an individual using hand spray application in a 100-m closed room, as might be in an actual pesticide application. Bursts of spray were for 15-30 s regularly over a period of 10 min. The IMS analyzer provided direct results without sample preparation. (From Armenia and Blanco, Ion mobility spectrometry as a high-throughput analytical tool in occupational pyrethroid exposure. Anal. Bioanal. Chem. 2012, 404(3), 635-648.) 

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Work safety, e.g. organic solvents, aerosols containing microorganisms. 

In this case, the most common sources of RNase contamination are hands and dust or aerosol with microorganisms. Therefore, latex or vinyl gloves should be worn and frequently changed when handling reagents and RNA samples. Tubes containing samples or reagents should be kept closed wherever possible. Furthermore, it is also important to keep isolated RNA on ice. 

Centrifugation and blending of products can lead to aerosol formation and containment of such activities to prevent transfer of live microorganisms is necessary. 

Example 19.3 Figure 19.2 shows the size distribution of a sneeze as given by Lidwell (1967) (10s droplets per sneeze). Assuming each of the droplets contains one or more viable microorganisms with a virus survival half-life of 2 min, determine the viable aerosol concentration as a function of time, using Eq. 19.1. 

In the MBL, halogens are very abundant in the form of sea salt aerosols which contain chloride and bromide. If there are ways to release reactive chlorine and bromine (i.e., other than acid displacement which mostly releases HCl) from the sea salt aerosol, then especially bromine could play a very important role in the chemistry of the MBL. Furthermore, organic iodine gases produced in the ocean by microorganisms (see Section 4.02.4.4) are emitted from the sea surface. These alkyl iodides are rapidly photolyzed, releasing iodine atoms, leading to very rapid reaction cycles that can also involve chlorine and bromine. 

All manufactured products are vulnerable to contamination by a myriad of aerosolized contaminants, including microorganisms, pyrogenic dust, ash, pollen, smoke, hydrocarbons, and other chemicals that are omnipresent in the environment (Pig. 1). Because of the potential dangers to the patient resulting from a parenteral product containing even minute quantities of these contaminants, exceptional measures are required to exclude them fromthe finished product. 

There are two general approaches, wet tests and aerosol challenge tests. Wet tests consider penetration of microorganisms in liquid suspension into sealed containers usually previously filled with sterile medium. The basic assumption is that the most vulnerable route for penetration of liquid filled containers by microorganisms is in the event of a continuous liquid film or bridge forming between the outside and the inside of a container. Aerosol challenge tests are less critical than wet tests and should be applied only when total exclusion of moisture from the containment system can be ensured by secondary barriers. 

Some of the older clinical centrifuges have been shown to be hazardous (390). The microhematocrit centrifuge, in particular, has been shown to produce aerosols. One frequently sees blood samples centrifuged in tubes without closures or with cotton plugs secured in the tubes by means of tape or other unsecure means. Remember that some tissue specimens contain viable infectious microorganisms, particularly hepatitis virus, and that open tubes, contaminated closures, and concomitant release of aerosols from blood sam-... 

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