Contamination factors

Corrosivity Contamination factors (incompatibility), oxidizing or reducing agent, dangerous reactions ... 

Sartor, J. D., Kruzic, P. G., Lane, W. B. and Mackin, J. L. (1968). Experimental Investigation of Plant Uptake Contamination Factors, Report No. USNRDL-TRC-68-57, Report No. AD-694531, and Report No. SRI-Proj-Mu-6502 (Stanford Research Institute, Menlo Park, California). 

Fomin, A.P. (1966) Biological effect of epichlorohydrin and its hygienic significance as an atmospheric contamination factor. Gig. Sanit., 31, 7-11 (in Russian)... 

The importance for proteomic studies of being performed on standardized samples cannot be emphasized enough. Several approaches have been developed to address the problem of tissue heterogeneity. Beads-based sample enrichment (BBSE) and laser capture microdissection (LCM) procedures are emerging as the methods of choice. The aim of these procedures is to eliminate, as much as possible, all confounding and contaminating factors in order to obtain a sample quality that can be compared with cell lines without the disadvantages of in vitro cultures. 

In our attempts to refine and standardize various phases of AAS analysis it has become quite apparent that scientific controls and standardization must be used throughout the entire spectrum of sample acquisition. This necessitates known and accepted sample collection procedures, beginning in the field (noting possible contamination factors) and continuing through the recording, laboratory, computation, and interpretive phases of analysis. 

The development of advanced techniques is important for the sensitive and effective detection of biological threat agents, particularly in cases where the analysis includes complex samples containing multiple contaminating factors. 

Figure 4, Typical decontamination factors achieved in WCF off-gas system. The contamination factor for a component is the ratio of the quantity entering to the quantity exiting per unit of time.

The mechanisms by which drugs are deposited in hair are not well understood but may include transfer from blood to the growing hair shaft, transfer from sweat and sebum (some sweat glands empty into hair follicles), and environmental contamination. Factors that may affect the deposition of drugs in hair also are not well established but may include the rate of hair growth, anatomical location of hair, type of hair, hair color (melanin content), effects of various hair treatments, and environmental contamination, especially for drugs that are smoked (marijuana, cocaine, heroin, and PCP). 

Used oil analysis serves as the measurement apparatus for the contamination factor. Start by establishing meaningful target levels for each of the machines, taking into account mechanical sensitivity, application and/or environment severity and the machine s criticality to production, safety, environmental protection and/or other aspects of the mission. Compare the actual performance to targeted performance and report the percentage of the machines that comply with contamination targets (Fig. 8). 

In the Guizhou Province in southwest China, local coal with an extremely high arsenic content (up to 3.5%) is used for cooking. Chili peppers dried over open coal-burning stoves contained > 500 mg As kg , compared with normal As levels < 1 mg kg . Similar levels were also found in other tainted foods and kitchen dust, whereas As in drinking water in this area does not appear to be an important contamination factor (Finkelman et al. 1999). 

The significant effect of traces of iron, nickel, copper and vanadium in petroleum feedstocks on processing economics has been responsible for the continuing attention focused on improvements in trace metal analytical procedures. This interest has intensified in our company because of the wide variety of crude oils now processed coupled with the need to meet more stringent contamination factors. These needs have increased demands on our laboratories for routine analyses at levels of less than 1 ppm. As a consequence our group was asked to evaluate requirements for trace metal analysis and to determine to what extent methods presently described in the literature could be adapted to our needs. 

Cf of metal elements is shown in Table 2.24 (Meng et al., 2008). First, the contamination extent was set off according to the contamination factor of metal elements, Cd>Zn>Pb>Cr>Cu. Consequently, Pb, Zn, and Cd were considered the main polluting elements in surficial sediments from Bohai Bay, and their distributions in sediments are shown in Fig. 2.56 (Meng et ah, 2008). 

Table 2.24. The contamination factor of metal elements in surficial sediments from Bohai Bay (Meng et al., 2008) (With permission from Elsevier s Copyright Clearance Center)...

Containment of the process to prevent ingress of contaminating factors and the release of materials that may affect the process worker and environment is a key factor in these processes. Microbiological containment of small-scale systems (below 20 L) in class in microbiological cabinets is possible, and a larger scale fermentation plant can be contained to P3 standards at least up to the 150-L scale. 

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