Benzalkonium Chloride: A Known Irritant and Novel Allergen
Bibliographic record
Abstract
BACKGROUND: Benzalkonium chloride (BAK), a detergent and preservative found in health care and household products, is an established irritant, yet BAK is seldom considered to cause allergic contact dermatitis. We have, however, observed positive patch test reactions more often than is typically reported. From 2001 through 2005 and 2006 through 2010, BAK was among the top 10 most frequent allergens in our standard series. OBJECTIVE: The aim of this study was to review the Mayo Clinic experience from 2000 to 2012 with patch testing to BAK. METHODS: An electronic patch test database was used to acquire results of patients who underwent patch testing for BAK 0.1% aqueous after it was introduced to the standard series in 2000 until 2012. Previous reports (1998-2000, 2001-2005, 2006-2010) from our institution were also reviewed. CONCLUSIONS: Our study showed BAK to be an allergen of increasing importance. From 1998 through 2000, 2001 through 2005, and 2006 through 2010, the rate of allergic patch test results to BAK increased. More than half of the reactions in each period studied were graded as macular erythema, with at least one third of all reactions deemed to be relevant. Irritancy rates were consistently low.
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How this classification was reachedexpand
Full frame machine prediction
Teacher imitationNot calibrated prevalence, not ground truth. Human validation pending. The Gemma side is a direct model label for every work in the frame, read from the title-only record. The Codex side is a classifier learned from the 10,348 direct Codex labels and calibrated to design-weighted sample rates; fields without enough sample support carry no Codex call. Candidate is the union of the two sides; consensus is their intersection. These outputs are machine_predicted_unvalidated and are not human labels.
Distilled classifier scores by category (both heads)
| Category | Codex | Gemma |
|---|---|---|
| Metaresearch | 0.000 | 0.001 |
| Meta-epidemiology (narrow) | 0.000 | 0.000 |
| Meta-epidemiology (broad) | 0.000 | 0.000 |
| Bibliometrics | 0.001 | 0.001 |
| Science and technology studies | 0.000 | 0.000 |
| Scholarly communication | 0.001 | 0.001 |
| Open science | 0.000 | 0.000 |
| Research integrity | 0.000 | 0.000 |
| Insufficient payload (model declined to judge) | 0.002 | 0.001 |
Machine scores (provisional)
The two teacher heads of the student model, read on this work. A score orders the frame for review; it never asserts a category, and the validation status ships verbatim with every row.
Baseline scores from an immature model (maturity gate not passed, 7 training rounds). Scores rank; they never assert a category.
score_only:v0-immature-baseline · verbatim from the scoring run: score_only means the number may rank works, and no category label ships from itClassification
machine, unvalidatedMachine predicted; a candidate call from one source (direct Gemma or distilled Codex), not a consensus.
How this classification was reached, model by model and score by score, is at the end of the page under "How this classification was reached".