How to use this book

Choosing a test concentration and vehicle

This book contains information on recommended patch test concentra-tions and vehicles for defined chemicals, products, and groups of either chemically or functionally related substances and chemicals. In addition, data are provided which may directly or indirectly influence decision making relevant to patch test procedures and which enable the inves-tigator easily to locate more detailed information. Thus, for every chemical it is stated whether or not:

  • it is monographed in the Merck Index (14th Edition, 2006, Merck & Co., Inc., Whitehouse Station, NJ, USA. http://www.merck.com/)
  • it is monographed in the CTFA Cosmetic Ingredient Dictionary and Handbook (11th Edition, 2006, The Cosmetic, Toiletry and Fragrance Association, Inc., Washington DC, USA. http://www.ctfa.org/)
  • it has caused photosensitivity reactions (for an alphabetical listing see Table 5)
  • it has caused immediate contact reactions (= contact urticaria) (for an alphabetical listing see Table 6)
  • it has caused patch test sensitization (for an alphabetical listing see Table 7)

The sources of the data presented here are:

  • the major textbooks on contact dermatitis, including the most recent versions of "Contact Dermatitis" (Springer, 4th Edition, 2006), the "Handbook of Occupational Dermatology" (Springer, 2004) and "Fisher's Contact Dermatitis" (BC Decker, 6th Edition, 2008)
  • the monographs on fragrance raw materials, published by the Research Institute for Fragrance Materials (RIFM) http://www.rifm.org/
  • all editions of the journal "Contact Dermatitis" from 1975 to march 2008, all editions of the journal "The American Journal of Contact Dermatitis" and its successor "Dermatitis" up to 2008
  • the Merck Index (14th Edition, 2006)
  • the CTFA Cosmetic Ingredient Dictionary and Handbook (11th Edition, 2006)
  • various sources on the internet, especially for looking up trade names and unfamiliar names as mentioned in the medical literature

The four main sections of this book are:

Table 1 This table contains information on test concentrations and vehicles for defined chemicals, mixtures of defined chemicals, plant products (extracts, essential oils etc) and other (more or less defined) compounds which have been used or may be used for patch testing
Table 2 This table is an alphabetical listing of abbreviations, and provides full chemical names and/or entry-names as used in Table 1
Table 3 This table contains information on test concentrations and vehicles for groups of either chemically or functionally related chemicals or substances.
Table 4 This table contains information on test concentrations and vehicles for products.

For the test concentration of defined chemicals, mixtures of chemicals and plant products, Table 1 should be consulted first. If a particular chemical is not found under the name that is known to, or preferred by, the investigator, synonyms/other names of this compound, if available, should be looked up in the table (for the choice of the nomenclature see "Explanation of Table 1").

When the chemical has been traced in the table, it is usually not difficult to decide on a test concentration and vehicle, as often only one concentration is given. When more than one concentration and/or vehicle are given which differ considerably, we have tried to make a recommendation on the basis of an assessment of literature data. Where such test advice could not be provided (which unfortunately is so in the vast majority of cases, because of the lack of reliable scientific data), the investigator has to decide on a test concentration/vehicle him/herself by examining the various test recommendations. The following observations may then be of some help:

  • the column "comments" sometimes refers to irritant reactions at certain concentrations and risk of patch test sensitization.
  • the test recommendations of Dr Cronin (5) seem to indicate a cautious approach. Not infrequently she advises two test concentrations, the higher of which being slightly irritant.
  • for 'new' allergens, it is often mentioned if and how many controls have been tested to exclude irritancy of the material used for patch testing.

If the chemical to be tested is not discussed in Table 1, Table 3 may provide a clue for testing by a recommendation for the group of chemicals to which the compound under study belongs. For test concentrations of products Table 4 should be consulted.