Allergo Journal International

, Volume 28, Issue 6, pp 167–182 | Cite as

Consumer protection and risk assessment: sensitising substances in consumer products

  • Hermann-Josef Thierse
  • Andreas LuchEmail author



The human immune system is confronted daily with a large, chemically-varied range of potentially sensitising substances. Skin sensitising substances are found, above all, in a plethora of consumer products, e. g. cosmetics, jewellery, earrings, toys, textiles, leather, other everyday commodities and, in some cases, also tattoos. These products may contain sensitisers such as fragrances, preservatives, dyes, or other additives. To provide a greater degree of consumer protection, there is a need for specific legal regulation and risk assessment, which covers each possible human exposure to a sensitising substance or mixture. This review article describes the background and pathway towards the development and implementation of an international legal framework for the classification and labelling of chemicals that contain potentially skin sensitising substances. This includes the implementation of the globally harmonized system of classification and labelling of chemicals (GHS), the classification, labelling and packaging (CLP) regulation, registration, evaluation, authorisation and restriction of chemicals (REACH), and the regulation of cosmetics, among other national laws and regulations. Assessment criteria for classification is derived from a suite of in vitro and in vivo assays, in addition to in silico approaches—validated by the organisation for economic cooperation and development (OECD)—as well as data derived from human studies.


New legislation for chemical and product safety is reflected in the classification and labelling of skin sensitising substances under Category 1, Subcategory 1A or 1B, within which the threshold concentrations of several materials are regulated, e. g. p‑phenylenediamine in hair dyes, nickel in piercings, chromium VI in leather and methylisothizolinone in cosmetics. In order to minimise the risk of human contact allergy from consumer products, the scientific committee on consumer safety (SCCS) and the German federal institute for risk assessment (BfR) investigate pathways of exposure and perform risk assessments using new in vitro approaches and new (immuno-) toxicological concepts (i. e. adverse outcome pathways [AOPs], key events as well as an integrated approach to testing and assessment [IATA]). In comparison to cosmetics, substances in textiles and other consumer products are less regulated. Major efforts in research and development are necessary to decode complex substance-specific molecular mechanisms in allergic responses and to define new substance-specific thresholds. Such efforts have been continuously proposed by the BfR with regard to fragrances for over 10 years.


Today, skin sensitising substances can be legally regulated and labelled and, depending on the exposure, their content in consumer products can be reduced or eliminated. Furthermore, the risk assessment of potentially sensitising substances makes consumer products safer. Further improvements in research approaches are required in the area of health and consumer protection with regard to allergy.


Contact allergy Product safety CLP hazard category for skin sensitisation 1, 1A, 1B REACH OECD Cosmetics Textiles P-phenylenediamine Nickel Methylisothiazolinone Chromium VI 



Allergic contact dermatitis


Adverse outcome pathway


Adaptation to the technical progress


German federal institute for risk assessment


Federal monitoring plan


German federal office of consumer protection and food safety


Classification, labelling and packaging


Chemical safety assessment


Derived no effect level


Direct peptide reactivity assay


European chemicals agency


European Union


Globally harmonized system of classification and labelling of chemicals


Guinea pig maximisation test


General product safety directive


High-performance liquid chromatography


Integrated approach to testing and assessment


Information network of German dermatological hospitals


German food, commodities and feed code (Lebensmittel‑, Bedarfsgegenstände und Futtermittelgesetzbuch)


Local lymph node assay






Molecular initiating event


Organisation for economic cooperation and development




Product safety law




(Quantitative) structure-activity relationship


Registration, evaluation, authorisation and restriction of chemicals


Risk management measures


Scientific committee on consumer safety


Sorbitan sesquioleate


United Nations


United Nations conference on environment and development


Weight of evidence



The authors would like to thank Dr. Blair Johnston (BfR) for his critical reading of the translated manuscript.

Conflict of interest

H.-J. Thierse and A. Luch declare that they have no competing interests.

Supplementary material

40629_2019_93_MOESM1_ESM.pdf (85 kb)
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Copyright information

© Springer Medizin Verlag GmbH, ein Teil von Springer Nature 2019

Authors and Affiliations

  1. 1.Department of Chemical and Product SafetyFederal Institute for Risk AssessmentBerlinGermany

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