నైరూప్య

Hair As An Indicator Of Trace Elements Bioaccumulation In Human Body: Optimization Of A Washing Procedure

Yassir Barkouch, A.Pineau, A.Sedki, J.C.Amiard

For many years, hair analysis has played an important role in the monitoring of toxic risks. Concentrations of trace elements in hair reflect their mean level in the human body. At the beginning of the XXth century, the use of hair was limited to forensic toxicology, for instance, to detect arsenical intoxications. Thereafter, its application was extended to other fields, such as anthropology, archaeology and history. Thus, interesting a posteriori revelations on the possible toxic etiology of the deaths of certain famous characters have been made. Measuring the concentrations of harmful trace elements(Pb, Cd and Hg) in hair can be used to monitor a population’s exposure to pollution or to estimate intake from contaminated foodstuffs. A further application is the biomonitoring of personnel occupationally exposed to heavy metals. To ensure the significance and reliability of results, the quality of the analytical procedure is paramount. Indeed, when measuring trace element levels in hair only the internal (endogenous) fraction should be taken into account, hence, the importance of the washing procedure used prior to analysis. The objective of this study was to test the effectiveness and aggressiveness of seven washing procedures to compare removal of endogenous elements and external contaminants. The procedure finally adopted was the one that most effectively removed all external contaminants without being too aggressive and removing the elements incorporated into the hair matrix during its growth, as this fraction alone reflects the accumulation of trace elements in the organism.