Contaminants, biologic

Among the major potential hazards affecting working environment are chemical (airborne contaminants), biological, and physical hazards,. ir contaminants are commonly classified as either particulate contaminants or gas and vapor contaminants. Common particulate contaminants include dusts, fumes, mists, aerosols, and fibers. 

An important specialized type of voltammetric system is a self-contained cell for the determination of 02 in the gas or solution phases. This is the so-called Clark electrode,66,67 which consists of a platinum or gold electrode in the end of a support rod that is covered by an 02 permeable membrane (polyethylene or Teflon) such that a thin film of electrolyte is contained between the electrode surface and the membrane. A concentric tube provides the support for the membrane and the means to contain an electrolyte solution in contact with a silver-silver chloride reference electrode. The Clark device has found extensive application to monitor 02 partial pressure in blood, the atmosphere, and in sewage plants. By appropriate adjustment of the applied potential it gives a voltammetric current plateau that is directly proportional to the 02 partial pressure. The membrane material prevents interference from electroactive ions as well as from surface-contaminating biological materials. Figure 3.19 illustrates one configuration for this important device. 

Phase imaging AFM Two phase polymer blends Surface contaminants Biological samples... 

The 1950s also saw the first evidence that chromium might be a dietary essential. Chromium is believed to promote the action of insulin and thus influences the metabolism of carbohydrates, fats, and proteins. Reports of severe human deficiency of chromium are rare and have been found primarily in people receiving only intravenous feedings for several months or years. Only a few laboratories in the world can accurately measure the amount of chromium in foods and body tissues because chromium is present in stainless steel, which is ubiquitous in analytical laboratories and easily contaminates biological samples. 

Detecting and identifying an aerosolized or contaminated biological agent before contact is made is referred to as remote or standoff detection." With aerosols, the initial criterion for monitoring and surveillance of potential biological agent at a... 

The removal and replacement of contaminated HEPA filters should be performed by trained professional personnel who take precautions against any exposure to themselves and to avoid contaminating the facihty. This will require planning ahead of time to provide sufficient access to the filters. For filters anticipated to be contaminated with human pathogens (or animal, where animal eiqiosures are a matter of concern), provision for isolating bag-out procedures should be made in advance. In general, HEPA filters should be disposed of as contaminated biological waste, preferably by incineration. 

Handle special wastes in any way including radioactive materials, chemical wastes, or contaminated biological materials. AU of these require special handling by specialists and precautions must be taken to ensure that these materials are not accidentally collected by custodians. The custodians should be given awareness training to ensure that they have sufficient knowledge to allow them to recognize these special wastes. 

AR546 7.2 Packaging and transportation of radioactively contaminated biological materials,... 

Pastoret PP (2010) Human and animal vaccine contaminations. Biologicals 38 332—334... 

The classification of biological risk is defined by Ordinance 3.214/78 of the Ministry of Labor and Employment, in its regulatory standards and job security (Brasil, 2002). Biohazards are represented by bacteria, fungi, parasites, viruses, among others. It is known that occupational exposure to potentially contaminated biological materials constitute a serious risk to health professionals in their workplaces. 

Prevent decomposition of contaminated biological waste. Biological wastes, such as an-... 

Figure 5 First-order FAB spectra obtained using glycerol (G) as the liquid matrix for kaempferol-3-O-rutinoside, isolated from a medicinal plant, with and without subsequent desalting. Reprinted with permission from Li QM, Dillen L and Claeys M (1992) Positive ion FAB analysis of flavonoid glycosides. Simple procedures for desalting and control of sodium salt contamination. Biological Mass Spectrometry 2Z 408-410. Copyright John Wiley and Sons Ltd.

Li QM, Dillen L and Claeys M (1992) Positive ion FAB analysis of flavonoid glycosides. Simple procedures for desalting and control of sodium salt contamination. Biological Mass Spectrometry 23 408- 410. 

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