Allergies account for some of the observations regarding appearance noted in discovery. In addition, allergies result in the production of secretions. These secretions are derived from blood and contain blood products. These secretions would have an alcohol level significantly higher than that of expired air.
Any contamination of the breath specimen by these secretions as the breath specimen passes over them, would result in an erroneous elevation of the BAL and the breathalyzer results, a form of pre-analytic error.
This has been presented by Michael Hlastala, PhD., entitled Paradigm Shift for the Alcohol Breath Testing which appeared in the peer review journal, Forensic Science, in March 2010, Volume, 55 No. 2.
{Breath test}