Hairdressers' occupational exposure to carcinogenic aromatic amines
Author
Summary, in English
The hairdresser occupation is classified as probably carcinogenic to humans based on an excess risk for urinary bladder cancer, but it is unclear if current work as a hairdresser entails such a risk. The overall aim of this thesis was to investigate if hairdressers have an ongoing exposure to selected carcinogenic aromatic amines.
We recruited 295 hairdressers, 32 consumers of hair dyes and 60 controls. All participants were non-smoking females, 18-55 years of age. Exposure over the past 4 months was determined for eight aromatic amines measured as haemoglobin (Hb) adducts. Hb adduct concentrations for hairdressers and consumers were not significantly higher than those of the controls for any of the eight aromatic amines. However, within the hairdresser group, ortho (o) and meta (m)-toluidine adduct concentrations tended to increase with the number of performed treatments with light-colour oxidative hair dyes. Furthermore, Hb adduct concentrations of o-toluidine increased significantly with the number of performed treatments of hair waving and m-toluidine adducts with the number of performed treatments with other oxidative hair dye.
Professional hair products, mainly oxidative hair dyes, were collected from hairdressing salons and analysed for o-toluidine content. o-Toluidine was found in most of the analysed oxidative hair dyes but with a wide range in concentrations, even for the same colours. For semi-permanent (non-oxidative) hair dyes, oxidizing agents, hair waving products, and bleaching products, the content of o-toluidine was low or below limit of quantitation.
To explore the effect of exposure to o- and m-toluidine among hairdressers, we determined telomere length and methylation of genes related to bladder or lung cancer. Hairdressers had a modest shortening of telomere length compared to non-hairdressers. No overall associations between telomere length and any of the Hb adducts were found, and no clear patterns between exposure as a hairdresser and hypermethylation of the selected genes.
In conclusion hairdressers seem to have an ongoing occupational exposure to o- and m-toluidine as indicated by the associations with performed treatments with light-colour oxidative hair dye, other oxidative hair dye and hair waving. This is further supported by our finding of o-toluidine in most of the analysed oxidative hair dyes. However, no clear patterns were found between exposure as a hairdressers and hypermethylation of genes associated with bladder cancer and lung cancer. We observed a modest shortening of telomere length among the hairdressers, but the causality of the observation is uncertain since no overall exposure-response association was observed.
We recruited 295 hairdressers, 32 consumers of hair dyes and 60 controls. All participants were non-smoking females, 18-55 years of age. Exposure over the past 4 months was determined for eight aromatic amines measured as haemoglobin (Hb) adducts. Hb adduct concentrations for hairdressers and consumers were not significantly higher than those of the controls for any of the eight aromatic amines. However, within the hairdresser group, ortho (o) and meta (m)-toluidine adduct concentrations tended to increase with the number of performed treatments with light-colour oxidative hair dyes. Furthermore, Hb adduct concentrations of o-toluidine increased significantly with the number of performed treatments of hair waving and m-toluidine adducts with the number of performed treatments with other oxidative hair dye.
Professional hair products, mainly oxidative hair dyes, were collected from hairdressing salons and analysed for o-toluidine content. o-Toluidine was found in most of the analysed oxidative hair dyes but with a wide range in concentrations, even for the same colours. For semi-permanent (non-oxidative) hair dyes, oxidizing agents, hair waving products, and bleaching products, the content of o-toluidine was low or below limit of quantitation.
To explore the effect of exposure to o- and m-toluidine among hairdressers, we determined telomere length and methylation of genes related to bladder or lung cancer. Hairdressers had a modest shortening of telomere length compared to non-hairdressers. No overall associations between telomere length and any of the Hb adducts were found, and no clear patterns between exposure as a hairdresser and hypermethylation of the selected genes.
In conclusion hairdressers seem to have an ongoing occupational exposure to o- and m-toluidine as indicated by the associations with performed treatments with light-colour oxidative hair dye, other oxidative hair dye and hair waving. This is further supported by our finding of o-toluidine in most of the analysed oxidative hair dyes. However, no clear patterns were found between exposure as a hairdressers and hypermethylation of genes associated with bladder cancer and lung cancer. We observed a modest shortening of telomere length among the hairdressers, but the causality of the observation is uncertain since no overall exposure-response association was observed.
Publishing year
2015
Language
English
Publication/Series
Lund University Faculty of Medicine Doctoral Dissertation Series
Volume
2015:71
Document type
Dissertation
Publisher
Division of Occupational and Environmental Medicine
Topic
- Clinical Medicine
Status
Published
Supervisor
- Maria Albin
- Bo A Jönsson
- Christian Lindh
- Karin Broberg Palmgren
ISBN/ISSN/Other
- ISSN: 1652-8220
- ISBN: 978-91-7619-150-7
Defence date
11 June 2015
Defence time
09:00
Defence place
Pufendorf Institute, Sölvegatan 2, Lund
Opponent
- Kåre Eriksson