N,N-Bis(2-ethylhexyl)-((1,2,4-triazol-1-yl)methyl)amin

MAK-Begründung, Nachtrag

  Andrea Hartwig¹ (Vorsitz der Ständigen Senatskommission zur Prüfung gesundheitsschädlicher Arbeitsstoffe, Deutsche Forschungsgemeinschaft)
  MAK Commission<sup>2

1</sup> Institut für Angewandte Biowissenschaften, Abteilung Lebensmittelchemie und Toxikologie, Karlsruher Institut für Technologie (KIT), Adenauerring 20a, Geb. 50.41, 76131 Karlsruhe, Deutschland
² Ständige Senatskommission zur Prüfung gesundheitsschädlicher Arbeitsstoffe, Deutsche Forschungsgemeinschaft, Kennedyallee 40, 53175 Bonn, Deutschland

Abstract

The German Senate Commission for the Investigation of Health Hazards of Chemical Compounds in the Work Area (MAK Commission) has re-evaluated N,N-bis(2-ethylhexyl)-((1,2,4-triazol-1-yl)methyl)amine [91273-04-0] with regard to its carcinogenicity and germ cell mutagenicity classification, its ability to be absorbed through the skin, its sensitization potential and whether an occupational exposure limit value (maximum concentration at the workplace, MAK value) can be derived. Relevant studies were identified from a literature search. N,N-Bis(2-ethylhexyl)-((1,2,4-triazol-1-yl)methyl)amine is corrosive to the skin of rabbits. The substance is a formaldehyde releaser and is expected to undergo rapid hydrolysis in aqueous solution. For this reason, the effects are attributed to the hydrolysis products formaldehyde, bis(2-ethylhexylamine) and 1H-1,2,4-triazol. There are no studies available that investigated the carcinogenicity, toxicity and genotoxic potential of N,N-bis(2-ethylhexyl)-((1,2,4-triazol-1-yl)methyl)amine in the upper respiratory tract or nose, which are the likely target organs. Formaldehyde was classified in Carcinogen Category 4 because it induces tumours in nasal tissue at concentrations that exceed its detoxification capacity. As a formaldehyde releaser, N,N-bis(2-ethylhexyl)-((1,2,4-triazol-1-yl)methyl)amine could likewise be classified in Carcinogen Category 4. However, because it is not possible to derive a MAK value for N,N-bis(2-ethylhexyl)-((1,2,4-triazol-1-yl)methyl)amine, the substance has been assigned to Carcinogen Category 2 with the footnote “Prerequisite for Category 4 in principle fulfilled, but insufficient data available for the establishment of a MAK or BAT value”. As there are no data available for the systemic bioavailability of N,N-bis(2-ethylhexyl)-((1,2,4-triazol-1-yl)methyl)amine and the formaldehyde released by hydrolysis in tissues, there is no experimental evidence that the formaldehyde reaches the germ cells. Therefore, N,N-bis(2-ethylhexyl)-((1,2,4-triazol-1-yl)methyl)amine has been classified in Category 3 B for germ cell mutagens. Data on the sensitizing effects in humans are not available. However, maximization tests in guinea pigs revealed a skin sensitizing potential, and the substance has therefore been designated with “Sh”. Skin contact is not expected to contribute significantly to systemic toxicity.

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