Methylchloroisothiazolinone/Methylisothiazolinone and Methylisothiazolinone Allergies Can Be Detected by 200 ppm of Methylchloroisothiazolinone/Methylisothiazolinone Patch Test Concentration

Abstract

For a correct diagnosis of MCI/MI and MI contact allergies, we advocate increasing the MCI/MI patch test concentration to 200 ppm along with a temporal inclusion of MI in the North American Contact Dermatitis Group baseline series.

Methylisothiazolinone Testing at 2000 ppm

“…14 Collation of findings in studies to date suggests 2000 ppm as the most optimal MI patch test concentration, and some evidence exists supporting this recommendation. 5,8,13,15 We detected an overall increase in the rate of positive patch testing to MI alone or to both MCI/MI and MI using MI at a concentration of 2000 ppm aqueous.…”

“…Past research has speculated that the concentration in the baseline series is too low, and as a result, ACD to MCI/MI might be missed. 5,10,11,13 Specifically, Bruze et al 5 state that almost 50% of positive reactions to MCI/MI are missed when testing at 100 ppm. In addition, testing MCI/MI at 100 ppm does not seem to be sufficient enough to detect all allergies to the combination; testing at 200 ppm has been recommended in other reports.…”

“…11 In addition, research demonstrates that adult cases of sensitization and exposure to MI exist throughout the life span. 4,6,7,9,13 It has been suggested that MI be tested at 2000 ppm to reduce false-negative reactions. 3,8 Many studies have evaluated different concentrations of MI in search of determining its optimal concentration for testing, and recently, it was added to both the North American and European Union baseline series through AllergEAZE (SmartPractice, Calgary, Alberta, Canada) at a concentration of 2000 ppm aqueous (0.2%).…”

Nuevos sensibilizantes en dermatitis de contacto alérgica de interés para todos los dermatólogos

“…Con una tasa de sensibilizació n de un 4% en Españ a en el añ o 2001 2 , su prevalencia ha ido creciendo de forma exponencial en los ú ltimos añ os, y en la actualidad se estima que es responsable de hasta un 10% de las DCA en Españ a y Europa [3][4][5] . Su uso está regulado por la Unió n Europea, y dado que se pensaba que su poder alergé nico residía en MCI, desde el añ o 2005 se permitió la utilizació n aislada de MI a altas concentraciones en cosmé ticos y productos del hogar, dando lugar a una auté ntica «epidemia» de casos de DCA por MI 6,7 y a un aumento de la sensibilizació n a MCI/MI en Españ a 5,8 , Europa 3,4,9 y Norteamé rica.…”

An economic approach to non-animal toxicity testing for skin sensitisation

“…If a substance belongs to a certain group of contact allergens (e.g. disinfectants, dyes, fragrances, preservatives), a mean prevalence for this group can be used (Schnuch et al, 2011;Leiva-Salinas et al, 2014). If no information is available, a mean prevalence value for contact allergens can be applied (Schnuch et al, 2011).…”