Trace analyses for wastewaters

Evaluation of solid phase microextraction for the analysis of hydrophilic compounds

“…MDL is defined as the statistically calculated minimum amount that can be measured with 99% confidence that the reported value is greater then zero (Glaser et al, 1981). Reagent water was fortified with the target analytes at concentrations designed to be less than ten times the calculated MDL.…”

Analysis of persistent halogenated hydrocarbons in fish feeds containing fish oil and other alternative lipid sources

“…The IDL was the ratio of three times the instrumental noise and the slope of the calibration curve of the analytes. On the other hand, the MDL was defined as the minimum concentration of a substance that can be measured and reported with 99% confidence that the analyte concentration was greater than zero [36] and it may vary as a function of the type of matrix sampled and the efficiency of the sample preparation procedures. The MDLs and LOQs were computed from seven replicates of the FO-100 fish feed spiked at 7.5, 12.5 and 12.5 ng/g dw for OCPs, PCBs, and PBDEs, respectively, and were calculated as follows: MDL = st (0.99,n−1) and LOQ = 10 s. Where, s was the standard deviation of the seven replicate measurements and t (0.99,n−1) = 3.14 was the t-distribution value taken at a confidence level of 0.99 and degrees of freedom of six.…”

Analytical Chemistry Laboratory Quality Assurance Project Plan for the Transuranic Waste Characterization Program

“…MDLs must be determined every six months, and must be less than or equal to the program-specified maximum values listed in Table 13-1. Detailed procedures for MDL determination, which are based on the method described by Glaser et al (1981), are included in the appropriate ACMM methods.…”

“…In these cases, the analyte concentration may be reported even though the IDL may exceed the PRDL. Detailed procedures for IDL determination, which are based those of the EPA Contract Laboratory Program (CLP) @PA, 1994b) and similar to the MDL determination method described by Glaser et al (1981), are included in the appropriate ACMM methods.…”