The Procter & Gamble Co., Central Product Safety and Regulatory & Technical Relations, Darmstadt, Germany and Cincinnati, OH, USA.
Regul Toxicol Pharmacol. 2012 Dec;64(3):459-65. doi: 10.1016/j.yrtph.2012.10.004. Epub 2012 Oct 13.
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.
随着局部淋巴结检测方法的出现，以及评估接触性过敏原相对皮肤致敏能力的有效性，已经开发出了一种定量风险评估 (QRA) 模型。该 QRA 过程包括：(a) 确定无预期致敏诱导水平 (NESIL)，(b) 纳入反映个体差异、产品使用模式和基质的致敏评估因素 (SAFs)，以及 (c) 估计消费者暴露水平 (CEL)。基于这些要素，可以通过将产品的 NESIL 除以个体 SAF 来计算可接受暴露水平 (AEL)。最后，将 AEL 与 CEL 进行比较，以判断对人类健康的风险。我们提出了一种简化的染发剂成分风险评估方法，利用精确的实验产品暴露数据。该数据集提供了在相关消费者使用条件下以单位面积剂量表示的确定剂量/单位面积浓度，称为实测暴露水平 (MEL)。因此，可以在 NESIL 与 MEL 之间进行直接比较，作为皮肤致敏风险的定量证明。本文通过参考两种特定的染发剂成分对苯二胺和间苯二酚来说明这一点。因此，与基于危害的染发剂成分分类相比，对这些稳健且具有毒理学相关性的数值进行比较被认为是一种改进。
