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Is quaternium-15 a formaldehyde releaser? Correlation between positive patch test reactions to formaldehyde and
Ashika Odhav1, Donald V Belsito
1Department of Dermatology, Columbia University Medical Center, New York, NY 10032, USA.
Background:
The question of whether quaternium-15 is a formaldehyde releaser is controversial. Understanding this relationship is critical because of the widespread use of quaternium-15 and the need to properly advise formaldehyde-allergic individuals.
Objectives:
This study aimed to look for an association between allergy to quaternium-15 and formaldehyde by correlating reactions to both and to correlate the intensity of positive patch test results to formaldehyde with reactivity to quaternium-15.
Methods:
This is a retrospective analysis of 1905 patients who underwent patch testing for allergic contact dermatitis. Associations were analyzed by χ testing.
Results:
Of all patients, 9.5% reacted to quaternium-15, 7.2% reacted to formaldehyde, and 5.4% reacted to both (P < 0.001). Of 137, 86 had strong (2 or 3+) and 51 had weak (1+ or +/-) formaldehyde reactions; there was no relationship between the severity of formaldehyde reactivity and responsiveness to quaternium-15 (P = 0.229). Sex analysis did not change these findings.
Limitations:
This study is limited by its retrospective analysis and small sample size.
Conclusions:
A statistically significant relationship exists between reactivity to quaternium-15 and formaldehyde; however, the severity of the formaldehyde reaction does not predict reactivity to quaternium-15. Despite coreactivity with formaldehyde, quaternium-15 may not be a significant formaldehyde releaser. The coreactivity between quaternium-15 and formaldehyde requires further studies.
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