Quality Control QC Procedures

Over the last 20 years the reliability of data produced by analytical laboratories has increased dramatically. Strict requirements have ensured that the data were produced under defined standards of quality with a stated level of confidence. The routine day-to-day activities (e.g., matrix fortifications) to control, assess, and ensure the quality of generated data are the quality controls associated with analytical processes. The management of the system that ensures that these processes are in place and functional is the quality assurance portion of the laboratory program to produce reliable data. 

Quality assurance (QA) is an essential part of analytical protocols. Each laboratory is required to detect and correct problems in analytical processes and to reduce errors to agreed-upon limits. To produce data that have acceptable quality, all laboratory members must follow established guidelines and protocols. Some of the essential elements that must be included in a QA program are as follows  

Laboratory practices (e.g., glass washing protocols) must be developed, reviewed, and updated with the staffs participation on a scheduled basis and followed strictly by all laboratory members  

Operating procedures (e.g., SOPs monitoring freezer temperatures daily) must be standardized, documented, and supplied to each member of the laboratory staff and updated on a set schedule  

Monitoring programs (e.g., surface water monitoring of supplies furnishing public drinking water) must be carefully designed. 

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Brandt [200] has extracted tri(nonylphenyl) phosphite (TNPP) from a styrene-butadiene polymer using iso-octane. Brown [211] has reported US extraction of acrylic acid monomer from polyacrylates. Ultrasonication was also shown to be a fast and efficient extraction method for organophosphate ester flame retardants and plasticisers [212]. Greenpeace [213] has recently reported the concentration of phthalate esters in 72 toys (mostly made in China) using shaking and sonication extraction methods. Extraction and analytical procedures were carefully quality controlled. QC procedures and acceptance criteria were based on USEPA method 606 for the analysis of phthalates in water samples [214]. Extraction efficiency was tested by spiking blank matrix and by standard addition to phthalate-containing samples. For removal of fatty acids from the surface of EVA pellets a lmin ultrasonic bath treatment in isopropanol is sufficient [215]. It has been noticed that the experimental ultrasonic extraction conditions are often ill defined and do not allow independent verification. 

The application of appropriate Quality Control (QC) procedures or criteria is a mandatory consideration in the deployment and analysis of SPMDs (e.g.. Petty et al., 2000a). Similar to any performance-based methodology or approach. 

For a section that embodies the rationale of the standard, subsection 5.9 is remarkably short. The laboratory must have quality control (QC) procedures that are documented, with QC data recorded in such a way that trends are detectable and, where practical, statistical techniques applied. Five QC techniques are offered as a nonexclusive list ... 

Although some efforts have been made (25-26), until now there have been no statistically sufficient, rapid and cost effective sensory quality control (QC) procedures against cork taint for either wineries or cork suppliers. At UC Davis, we have developed a Cork Sensory QC Manual (27) which evaluates the major valid sampling procedures, and exemplifies their use based on a case study at a premium winery in California. In addition, the manual provides instructions for a taste panel evaluation which is essential for wineries in order test their winemakers and cellarmasters as well as the tasting room staffs sensitivities to detect the off-odor. Once individual... 

Many laboratories operate quality control (QC) procedures to underpin sample preparation methods. Laboratories processing large numbers of relatively uniform samples, as in a production line environment, or research laboratories processing a smaller number of samples with varied matrices, have effectively the... 

The quality of the analytical work cannot be maintained without adequate quality control (QC) procedures. The meaning of the term quality control often varies according to context. In general QC is the overall system of activities used to fulfill requirements for documentation of quality. The system should be satisfactory, adequate, dependable, and economic. Examples of quality control are control charts, blank determination, blind samples, and repetitive determinations. The number of test results to be obtained from the analysis of each sample is related to the purpose of the analytical work. As guidance for QC purposes, it is necessary to analyze at least one sample in duplicate in every 10 determinations of the analyte. 

Quality control (QC) Procedures used as part of quality assurance. 

An associated consideraticm for selectiOTi of analytical methods is whether they have been extensively tested for the specific application and, if it is a new procedure, whether it has been compared to standard methods and incorporates quality control (QC) procedures. Uniform use of extensively-tested methods and QC allows for comparisons of data results collected across different studies and environments over time. 

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