Development and validation of Graphite Furnace Atomic Absorption Spectrometry method and its application for clinical evaluation of blood lead levels among occupationally exposed lead smelting plant workers.

Abstract

The growing interest in estimating the blood lead levels, for early detection of lead exposure, warranted a need for a validated analytical method for trace levels estimation of lead. The present study aimed to develop an analytical method for detecting trace amounts to elevated levels of lead in human blood using the Graphite Furnace Atomic Absorption Spectrometry technique and its application in evaluating blood lead levels among occupationally exposed individuals. The method validation was performed with standard test parameters including linearity, recovery, precision, method detection limit, and limit of quantification. The validation results for each performance parameter were in agreement with acceptable criteria as per standard guidelines. The correlation was observed as optimum linear (R2 = 0.998) between absorbance and lead concentration range from 0 to 10µg/dL. The recoveries for spiked samples ranged between 95 and 105%. The calculated value for the method detection limit was 0.16µg/dL and the limit of quantification was 0.51µg/dL. The precision for all spiked concentrations was below 10% of the relative standard deviation. Evaluation of lead exposure among occupationally exposed individuals revealed the study population had found average blood lead level (42.80 ± 12.47µg/dL), which was above the upper acceptable limit suggested by Occupational Safety and Health Administration, USA. The majority of system-specific symptoms were observed among study groups having mean blood lead levels above 40µg/dL. However, sociodemographic status and employment factors were found possible determinants of the prevalence of high blood lead levels.