Hair Analysis Panel Discussion: Section 4.0
Factors Influencing The Interpretation Of Analytical Results
Panelists identified several factors that influence, and more often than not can limit, the interpretation of hair analysis results. In light of these factors, the panelists generally concluded that hair analysis findings need to be used and interpreted very cautiously. Even if issues related to the reliability and reproducibility of the data are resolved, panelists stressed repeatedly, several factors limit the utility of hair analysis as an exposure and diagnostic tool. Scientists and clinicians currently know little about what such measurements mean in terms of predicting or treating clinical disease (see also Section 5,).
During the meeting, several factors influencing the interpretation of hair analysis data were discussed:
- Inconsistent sample collection and preparation methods (e.g.,
sample location, cutting method, sample storage). (Panelist
discussions related to methodological issues are detailed in
- Difficulties in distinguishing metals deposited externally
from those incorporated internally from the hair follicle.
- Exposure chronology and conditions (e.g., exposure period
of interest, hair growth cycle, other exposures, etc.).
- The questionable reliability and variability of "reference" ranges. That is, what defines an "elevated" level?