Problems with Accuracy and Precision

While the stringent procedures required to control lead contamination of samples have been detailed in several reports (e.g., Flegal and Smith 1992b NRC 1980, 1993 Settle and Patterson 1980 Versieck et al. 1982) in addition to those previously cited, many laboratories still have not adopted these requisite procedures for measuring low levels of lead. Analytical reagents and inadequately cleaned labware, as well as contaminated sample 

Spurious contamination of samples with extraneous lead is in many cases a significant source of imprecision in measurements of low blood lead levels ( 5 fig/dL). This source of imprecision is not unique to measurements of 

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