Analysis, laboratory water

Spike recoveries for samples are used to detect systematic errors due to the sample matrix or the stability of the sample after its collection. Ideally, samples should be spiked in the field at a concentration between 1 and 10 times the expected concentration of the analyte or 5 to 50 times the method s detection limit, whichever is larger. If the recovery for a field spike is unacceptable, then a sample is spiked in the laboratory and analyzed immediately. If the recovery for the laboratory spike is acceptable, then the poor recovery for the field spike may be due to the sample s deterioration during storage. When the recovery for the laboratory spike also is unacceptable, the most probable cause is a matrix-dependent relationship between the analytical signal and the concentration of the analyte. In this case the samples should be analyzed by the method of standard additions. Typical limits for acceptable spike recoveries for the analysis of waters and wastewaters are shown in Table 15.1. ... 

The cost estimate should include provisions for any required satellite boiler water analysis laboratories. The central control lab cannot normally handle analyses of widely spread boilers satisfactorily. The designers, while remembering satellite water laboratory facilities for the utilities area, might overlook similar facilities for the steam generation in the process area. 

The required volume for the analysis of water samples from a drainage flow, stream, or river is collected from a depth of up to 50 cm at the center of a flow using an appropriate sampling bottle. A sample size of 1000 mL should be sufficient for the usual type of determination. The sampling bottle and bottles for storage and shipment should be well washed with an appropriate organic solvent and distilled water so that the sample is not contaminated, and keeping those bottles in a clean container is recommended. It is recommended that samples taken are kept below 5 °C and shipped to the laboratory as soon as possible. 

EPA. 1983a. Methods for chemical analysis of water and wastes. Methods 239.1 and 239.2. Cincinnati, OH U.S. Environmental Protection Agency, Office of Research and Development, Environmental Monitoring and Support Laboratory. EPA Report No. 600/4-79-020... 

We mentioned in Chapter 2 (Section 2.6.1) that a purge-and-trap procedure sometimes precedes an analysis by gas chromatography. An example of this procedure is found in the City of Lincoln, Nebraska, Water Treatment Plant Laboratory. Water treatment includes chlorination. When water is chlorinated, chlorine reacts with organic matter to form trihalomethanes (THMs), such as chloroform, bromoform, bromodichloromethane, and chlorod-ibromomethane. THMs in water are regulated by the Safe Drinking Water Act, and so the laboratory must analyze the treated water to determine their concentration. 

Water Quality. Laboratory analysis of water salinity, hardness, and total suspended solids should be included to help prospective bidders select proper coalescing media, equipment metallurgy, and coating requirements. 

One should not conclude that trace analysis of water systems is a hopeless undertaking. It is possible to get results which are consistent and which seem to be reliable, but it does involve much effort and attention. One does not get satisfactory results without careful, critical appraisal of all conceivable variables involved. An example of the approach which is necessary is the recent work by Andersen in our laboratory on strontium and barium distribution in the Atlantic Ocean (I, 2). 

The first application of immunoassay methodology for residue chemistry was in the analysis of water. Much of this effort was devoted to the analysis of -triazine herbicides, primarily atrazine. Many researchers studied the feasibility of immunoassays and restricted their analyses to field samples fortified in the laboratory (Bushway et al., 1988 Wittmann and Hock, 1989 Rubio et al., 1991 Giersch et al., 1993b Lawruk et al., 1993 Dinelli et al., 1995 Rodolico et al., 1997) or to reagent water fortified in the laboratory (Lentza-Rizos, 1996). 

Concerns for the VOC loss from water samples during transportation by air have been raised on occasion. Laboratory studies, however, have demonstrated that there is no discernable difference between VOC data obtained from analysis of water samples shipped by land and by air (Craven, 1998). The notion of unsuitability of air transportation for air samples collected in Tedlar bags is also common. However, if Tedlar bags are filled to 2/3 of their capacity, they survive air travel without leaking or bursting. 

Laboratory control samples are analyte-free matrices (reagent water or laboratory-grade sand) fortified (spiked) with known concentrations of target analytes and carried throughout the entire preparation and analysis. Laboratories prepare and analyze these batch QC check samples at minimum frequency of one LCS/LCSD pair for every preparation batch of up to 20 field samples. Laboratory control samples serve two purposes ... 

A common way to assess the matrix bias is to analyse a drinking water (therefore containing a matrix) in the proficiency testing. For this analysis, laboratories calibrate their instruments using standard, commercial or in-house solutions. If a CRM is available, a possible matrix effect can be corrected by adjusting operational instrument parameters to match the certified value. 

Supplement to the 15 th edn. of Standard Methods for the Examination of Water and Waste Water. Selected Analytical Methods Approved and Cited by the US Environmental Protection agency. American Public Health Association, American Waterworks Association, Water Pollution Control Federation, Sept. (1978). Methods S60 and S63. Methods for benzidine, chlorinated organic compounds, pentachlorophenol and pesticides in water and waste water (Interim, Pending issuance of methods for organic analysis of water and wastes, Sept. 1978), Environmental Protection Agency, Environmental Monitoring and Support Laboratory (EMSL). 

Laboratory methods. Methods for arsenic analysis in water, food, and biological samples... 

BCEPD. 1994a. Section F. Toxicity test methods. British Columbia Environmental Laboratory Manual For for the Analysis of Water, Wastewater, Sediment and Biological Materials, 1994 ed. Laboratory Services, Environmental Protection Department, Ministry of Environment, Lands and Parks, Province of British Columbia, B.C., Canada, pp. F-l to F-13. 

The spiking solution for analysis of PAHs in RM07 was prepared also in acetonitrile. The robustness of the reconstitution protocol for this spring water was verified by the Organic Analysis Laboratory of the RM Unit at IRMM. Several samples were analysed following the protocol for liquid-liquid extraction given to the PT participants. The standard deviation for reconstitution was found to be lower than 10% for all 9 PAHs included in the study. 

Use Water analysis, laboratory reagent, electroplated tin coating baths, manufacture of intermediates and dyes, pharmaceuticals. 

Analysis of waters for viruses is more difficult because of their small size, about 10 to 300 nm average diameter. Also, viruses need susceptible living cells such as chick embryos or tissue cultures for cultivation and identification in the laboratory, which make them more difficult to work with. Nevertheless, viruses represent an important microbiological class for water and wastewater-monitoring programs since serious waterborne diseases such as polio and hepatitis are transmitted in this way. 

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