Quantitative risk assessment for skin sensitisation: consideration of a simplified approach for hair dye ingredients.
With the availability of the local lymph node assay, and the ability to evaluate effectively the relative skin sensitizing potency of contact allergens, a model for quantitative-risk-assessment (QRA) has been developed. This QRA process comprises: (a) determination of a no-expected-sensitisation-induction-level (NESIL), (b) incorporation of sensitization-assessment-factors (SAFs) reflecting variations between subjects, product use patterns and matrices, and (c) estimation of consumer-exposure-level (CEL). Based on these elements an acceptable-exposure-level (AEL) can be calculated by dividing the NESIL of the product by individual SAFs. Finally, the AEL is compared with the CEL to judge about risks to human health. We propose a simplified approach to risk assessment of hair dye ingredients by making use of precise experimental product exposure data. This data set provides firmly established dose/unit area concentrations under relevant consumer use conditions referred to as the measured-exposure-level (MEL). For that reason a direct comparison is possible between the NESIL with the MEL as a proof-of-concept quantification of the risk of skin sensitization. This is illustrated here by reference to two specific hair dye ingredients p-phenylenediamine and resorcinol. Comparison of these robust and toxicologically relevant values is therefore considered an improvement versus a hazard-based classification of hair dye ingredients.
The Procter & Gamble Co., Central Product Safety and Regulatory & Technical Relations, Darmstadt, Germany and Cincinnati, OH, USA. goebel.c.1@pg.com
Carsten
C
Goebel
Thomas L
TL
Diepgen
Maya
M
Krasteva
Harald
H
Schlatter
Jean-Francois
JF
Nicolas
Brunhilde
B
Blömeke
Pieter Jan
PJ
Coenraads
Axel
A
Schnuch
James S
JS
Taylor
Jacquemine
J
Pungier
Rolf
R
Fautz
Anne
A
Fuchs
Werner
W
Schuh
G Frank
GF
Gerberick
Ian
I
Kimber
D000818:Animals; D003257:Consumer Product Safety; D005260:Female; D006202:Hair Dyes / Q000737:chemistry / Q000633:toxicity*; D006801:Humans; D023441:Local Lymph Node Assay; D051379:Mice; D008808:Mice, Inbred CBA; D010655:Phenylenediamines / Q000633:toxicity; D012118:Resorcinols / Q000633:toxicity; D018570:Risk Assessment / Q000379:methods; D012882:Skin Tests / Q000379:methods*; D013552:Swine
D006202:Hair Dyes; D010655:Phenylenediamines; D012118:Resorcinols; C029728:4-phenylenediamine; C031389:resorcinol