Answer to Question #7141 Submitted to "Ask the Experts"

Over the past several years, I have taken three phone calls from private citizens who have received "hair elements" analysis from several companies. This hair analysis lists 16 "toxic elements," including uranium, and 23 "essential and other elements." All results are in micrograms/gram. A percentile ranking is also given ranging from the 2.5 percentile to the 97.5 percentile. Methodology lists inductively coupled plasma-mass spectrometry. The main reason for the concern for the three individuals who called was the fact that the uranium in hair results were elevated in all three cases, with values ranging from 3.25, 0.45, and 0.42 microgram/gram of hair. These results listed the individuals in the 95^th percentile. All three households were on well water, two were on private wells, and one used a community well. Natural uranium in well water analysis by the Pennsylvania Department of Environmental Protection, Radiation Laboratory showed 17, 3.3, and 2.5 pCi/L, respectively. None of the individuals were determined to work in any type of occupation where exposure to urainum could be expected.

Questions:
If occupation, food, and water can be excluded as sources of elevated uranium values in hair, can it be reasonably concluded that the hair elemental analysis may be in error?

Analysis of uranium in hair is not an accepted nor reliable method of determining the uranium content in the body. Uranium is a heavy metal and is excreted in the hair and nails, but hair analysis for uranium is subject to inordinately high erroneous results from uranium contamination of the hair from shampoos, soaps, hair dressings, dyes, and hair treatments of various types. Moreover, since uranium is ubiquitous throughout the environment, the hair sample must be carefully obtained, handled, packaged, and shipped under rigid controls to ensure that it is not contaminated by coming into contact with materials containing environmental uranium which could be transferred to the hair sample. Erroneously high results can also occur if analytical procedures are not rigidly controlled and performed with scrupulous care. Controls include appropriate washing of the sample to remove possible surface uranium and use of special certified ultra-pure reagents. Labware must likewise be free of uranium; uranium may leach from glassware and contaminate the sample, leading to erroneously high readings. Since the hair samples are so small, even a tiny amount of uranium contamination may give a grossly exaggerated and erroneous result.

There are few, if any, data in the peer-reviewed scientific literature relating to what normal levels of uranium in hair are, or how these levels relate to uranium intake, amount in the body, and the amount excreted in the hair. Thus, there is a paucity of data regarding the uranium content of hair and what constitutes the "normal" range. There are no generally recognized established standards for uranium in hair. Background levels of uranium in hair are highly variable from person to person and region to region, depending in large measure on dietary factors as most of the uranium in our bodies comes from the food that we eat.

Ron Kathren, CHP