National monitoring methods

The workhorses in national monitoring programs are multi-residue methods. Any official method collection of any EU Member State contains at least one multi-residue method. For multi-analyte and/or multi-matrix methods, it is likely to be impractical to validate a method for all possible combinations of analyte, concentration and type of sample matrix that may be encountered in subsequent use of the method. Therefore, initial validation should incorporate as many of the target analytes and matrices as practicable. For practical reasons this validation and the evaluation of other methods with limited scope often cannot be conducted in inter-laboratory studies. Other concepts based on independent laboratory validation or validation in a single laboratory have been developed and can provide a practical and cost-effective alternative (or intermediate) approach. 

Cassinelli ME. 1986. Progress toward developing a monitoring method for hydrogen cyanide in air. National Institute for Occupational Safety and Health, Division of Physical Sciences and Engineering, Method Research Branch, Cincinnati, OH. NTIS No PB86-23-6171. 

Chao, L. Wang, L.K. Wang, M.H.S. Use of the Ames Mutagenicity Bioassay as a Water Quality Monitoring Method, PB88-168422/AS US Department of Commerce, National Technical Information Service Springfield, VA, 1986 25 p. 

NCRP (1978c). National Council on Radiation Ph otection and Measure ments. Instrumentation and Monitoring Methods for Radiation Protection NCRP Report No. 57 (National Council on Radiation Protection and Measurements, Bethesda, Maryland). 

Sisterson, D. L. Bowersox, V. C. Olsen, A. R. Meyers, T. P. Vong, R. L. Deposition Monitoring Methods and Results State of Science/Technology Report No. 6 National Acid Precipitation Assessment Program Washington, DC,... 

Monitoring items include the measurement of the 7 heavy metal indexes Cu, Pb, Zn, Cd, Cr, Hg and As. Sediments decomposition and monitoring methods can be found in Part 5 of The Specification for Marine Monitoring—Sediments Analysis (GB17378.5-2007). For Cu and Zn, the flame atomic absorption spectrophotometry is adopted for Pb, Cd and Cr, the nonflame atomic absorption spectrophotometry is used For Hg and As, the atomic fluorescence spectroscopy is applied. The accuracy of standard substances is also measured according to national offshore sediment analysis. The analysis results meet the requirement. During the analysis, reagent blank and parallel samples are casually measured, the results of which show that the analysis process is not polluted and the relative standard deviation for the parallel samples are all lower than 10%. 

Wastewater quality was monitored using the China national standard methods of china. The oil components in the wastewater were monitored by a petroleum industry standard method, using ultraviolet spectrophotometer. 

A completely different approach is process monitoring. Based on fill classification systems, the behaviour of a fill mass may be assured by following a specified work method. For instance, a certain required compaction of a certain class of fill will be achieved in a layer of say 2 m thickness after 10 passes of a certain specified roller. In this case the process is monitored in other words, the requirements are fulfilled when the roller has indeed executed the prescribed number of passes. The relation between classification, work method and fill mass behaviour can be obtained either from (national) codes of practise or by trial testing. The process monitoring method assumes a delivery of constant fill quality and will provide information to support the objectives of a method specification. 

Analysis of Standards The analysis of a standard containing a known concentration of analyte also can be used to monitor a system s state of statistical control. Ideally, a standard reference material (SRM) should be used, provided that the matrix of the SRM is similar to that of the samples being analyzed. A variety of appropriate SRMs are available from the National Institute of Standards and Technology (NIST). If a suitable SRM is not available, then an independently prepared synthetic sample can be used if it is prepared from reagents of known purity. At a minimum, a standardization of the method is verified by periodically analyzing one of the calibration standards. In all cases, the analyte s experimentally determined concentration in the standard must fall within predetermined limits if the system is to be considered under statistical control. 

High performance Hquid chromatography (hplc) may be used to determine nitroparaffins by utilizing a standard uv detector at 254 nm. This method is particularly appHcable to small amounts of nitroparaffins present, eg, in nitro alcohols (qv), which caimot be analyzed easily by gas chromatography. Suitable methods for monitoring and deterrnination of airborne nitromethane, nitroethane, and 2-nitropropane have been pubUshed by the National Institute of Occupational Safety and Health (NIOSH) (97). Ordinary sorbant tubes containing charcoal are unsatisfactory, because the nitroparaffins decompose on it unless the tubes are held in dry ice and analyzed as soon after collection as possible. 

Pubhc concerns about pesticides in the diet of infants and children resulted in an expert committee convened by the U.S. National Academy of Sciences which devoted four years to the review of all available data. A consensus report was issued in 1993 (80). A number of recommendations for further work to more precisely define what constitutes the diet of infants and children were made. No risk could be estimated. The residue data reviewed by the panel were mainly from monitoring studies conducted by the PDA using multiresidue methods to analyze fresh produce and market basket samples collected from various geographic areas (81,82). These and other rehable scientific studies have demonstrated that relatively few food samples contain detectable residues. Most residues are far below estabhshed tolerances which are set above the maximum residue found in treated raw agricultural... 

Regulatory and advisory bodies publish methods for ambient air analysis sueh as those issued by the British Standards Institute and the US Environment Proteetion Ageney (Tables 10.24 and 10.25, respeetively). Methods for assessment of workplace air are published by the Health and Safety Exeeutive. Some of these are generie methods (Table 10.26) whilst others are eompound speeifie (Table 10.27). Examples of other offieial methods for monitoring workplaee air quality are those published by the British Standards Institute (Table 10.28), and the US National Institute of Oeeupational Safety and Health (Table 10.29). Table 10.30 provides additional guidanee on analytieal teehniques for a seleetion of substanees. 

Nyer, E.K. Innovative Biological Treatment of Contaminated Groundwater. In First National Outdoor Action Conference on Aquifer Restoration, Groundwater Monitoring, and Geophysical Methods, May, 1987. 

The purpose of this chapter is to describe the analytical methods that are available for detecting, measuring, and/or monitoring methyl parathion, its metabolites, and other biomarkers of exposure and effect to methyl parathion. The intent is not to provide an exhaustive list of analytical methods. Rather, the intention is to identify well-established methods that are used as the standard methods of analysis. Many of the analytical methods used for environmental samples are the methods approved by federal agencies and organizations such as EPA and the National Institute for Occupational Safety and Health (NIOSH). Other methods presented in this chapter are those that are approved by groups such as the Association of Official Analytical Chemists (AOAC) and the American Public Health Association (APHA). Additionally, analytical methods are included that modify previously used methods to obtain lower detection limits and/or to improve accuracy and precision. 

The US Food and Drug Administration (FDA) evaluates methods to be used in government regulatory laboratories for the determination and confirmation of drug residues in food derived from animal products. The FDA Center for Veterinary Medicine (CVM) oversees the validation (i.e., demonstration that the method is suitable for use) via a protocol known as a method trial. CVM ensures that the appropriate government laboratories have the tools needed to monitor the Nation s food supply. 

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