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    7. Volume 11 (2026)
    8. Issue 2
    9. p-Chloranilin – Ableitung eines BAR
Cover: The MAK Collection for Occupational Health and Safety

The MAK Collection for Occupational Health and Safety

German Research Foundation – Permanent Senate Commission for the Investigation of Health Hazards of Chemical Compounds in the Work Area
(MAK Commission)

ISSN 2509-2383



p-Chloranilin – Ableitung eines BAR

Beurteilungswerte in biologischem Material

Isabell Schönrath1
Gabriele Leng2
  Hans Drexler3 (Leitung der Arbeitsgruppe „Beurteilungswerte in biologischem Material“ der Ständigen Senatskommission zur Prüfung gesundheitsschädlicher Arbeitsstoffe, Deutsche Forschungsgemeinschaft)
  Andrea Hartwig4 (Vorsitz der Ständigen Senatskommission zur Prüfung gesundheitsschädlicher Arbeitsstoffe, Deutsche Forschungsgemeinschaft)
  MAK Commission5

1 Currenta GmbH & Co. OHG, CUR-SIT-ABG-GS-BLM – Institut für Biomonitoring, 51368 Leverkusen, Deutschland
2 40699 Erkrath, Deutschland
3 Friedrich-Alexander-Universität Erlangen-Nürnberg, Institut und Poliklinik für Arbeits-, Sozial- und Umweltmedizin, Henkestraße 9–11, 91054 Erlangen, Deutschland
4 Institut für Angewandte Biowissenschaften, Abteilung Lebensmittelchemie und Toxikologie, Karlsruher Institut für Technologie (KIT), Adenauerring 20a, Geb. 50.41, 76131 Karlsruhe, Deutschland
5 Ständige Senatskommission zur Prüfung gesundheitsschädlicher Arbeitsstoffe, Deutsche Forschungsgemeinschaft, Kennedyallee 40, 53175 Bonn, Deutschland

Abstract

The German Commission for the Investigation of Health Hazards of Chemical Compounds in the Work Area evaluated the data for 4-chloroaniline [106-47-8] to derive a biological reference value (BAR). p-Chloroaniline is an intermediate in organic synthesis and is used in the manufacture of pharmaceuticals, plant protection products and dyes. As a potent inducer of methaemoglobin formation, the hazards regarding its acute toxicity surpass the carcinogenic potential. Hence, several accidents with a consecutive cyanosis are reported. Besides the methaemoglobin level, two other, more specific biomarkers are known: p-chloroaniline set free from the haemoglobin adduct and p-chloroaniline in urine. p-Chloroaniline after hydrolysis represents the sum of all N-conjugated phase II metabolites which are then back-converted to their mother compound. Based on studies of the general population, a BAR of 1 µg p-chloroaniline (after hydrolysis)/l urine has been derived. The smoking status did not influence the urinary levels of p-chloroaniline.

Keywords

p-Chloroaniline, biological reference value, BAR, background exposure