Hair dresser is a risk occupation  due to wet-work and exposure to a multitude of chemical substances giving rise to both irritant and possible allergic contact dermatitis. Already during education, protective measures are taught. Even so, hairdressers run a high risk of occupational hand dermatitis and it is important that advice  given by occupational dermatologists are accurate with regard to the hairdressers’ actual work exposure and preventive measures. Studies have shown that educational programmes aiming at minimizing wet-work, learning correct use of gloves and acquiring knowledge on correct  skin care, actually improve working conditions 12. However, a recent report has shown that, despite educational programs, hairdresser apprentices are still at increased risk of acquiring  hand eczema 3. Furthermore the hairdressers seem to acquire hand dermatitis after only a few years work. According to Lysdal et al. 4, in Denmark hairdressers remain in the profession on average for 8.4 years and where hand dermatitis is  a common reason for leaving the trade 4.

Gloves are usually evaluated with regard to the protective quality in in vitro studies 5. However the hairdressers wear the gloves in their daily work, the glove is exposed to wear and tear, water and a multitude of chemicals. A more realistic evaluation of skin protection provided by a glove would be achieved by performing in vivo provocation tests with commonly used hair dyes, comparing different glove materials. In a previous in vivo study 6 we have shown that with regard to hair-colouring products containing p-phenylenediamine (PPD) the nitrile glove was superior. In this study we wanted to test the protective effect of gloves further since not only PPD is used as hair colouring substance and hair dyeing also is performed at home where exposure conditions and glove recommendations may be different.

The gloves supplied in the hair dye for home use was analysed with Agilent Cary 630 FTIR spectrometer and it was found that the material was polyethylene. The average thickness of the gloves measured with a micrometer screw-gauge was within a range of 0.03- 0.13 mm (Table 1).

All the volunteers were tested with the open chamber test without any glove membrane (positive control) for 45 min of exposure with the 3 HDp, (HDp-TDA-S, HDp-PPD, HDp-ME-PPD) and for 30 min with the HDhu-TDA-S and all  developed positive reactions except for two who did not react to the test with HDp-ME-PPD (Figure 3, Table 3).

With the open chamber test with the 4H^® glove (negative control) and when the 4 hair dyes were tested with the 2 nitrile gloves  there were no positive.

The polyvinyl chloride glove did not give any protection in 6 volunteers when used with the hair dye HDp-TDA-S, and neither in 5 volunteers when used with HDp-PPD and HDhu-TDA- S. Regarding the hair dye HDp-ME-PPD however no  reactions were noted with the polyvinyl chloride glove (Table 3). Statistically, the 4H^® glove gave better protection than the polyvinyl chloride glove for all hair dyes except HDp-ME-PPD (Table 4). There was no difference between the nitrile gloves and 4H^®. The 2 nitrile gloves gave b etter protection than the polyvinyl chloride against the HDp-TDA-S in 6 subject, results being statistically significant (p= 0.031); between the HDp-PPD and the HDhu-TDA-S the difference was not significant however with a result close to statistically so  (p=0.062). No difference in term of reactions detected on the skin at test reading 1 (D4) and 2 (D7) was found between the nitrile and polyvinyl chloride gloves tested with HDp-ME-PPD.

The polyethylene glove protected all 7 tested individuals exposed for 30 min to the HDhu-TDA-S, and all the 5 individuals tested with HDp-ME-PPD for 45 min. With this longer exposure time, there was no protection obtained neither with the polyethylene glove concerning 4 of  the 5 tested individuals with HDp-TDA-S nor for 2 of the 5 volunteers tested with HDp-PPD (Table 3). Comparing the negative control with the polyethylene glove concerning the protection against the HDp-TDA-S, a statistical significance was indicated (p= 0.062) (Table 4). The 4H^® glove and the polyethylene glove gave the same protection with HDhu-TDA-S.

When tested with the HDhu-TDA-S hair dye for 30 minutes, the protection of polyvinyl chloride was adequate only for  2 subjects of 7. In the small group of 5 subjects tested with the polyethylene gloves and professional hair dyes at 45 minutes, results were not statistically significant but the trend comparing polyethylene and polyvinyl chloride gloves was the same when they were tested with HDp-ME-PPD and with HDp-TDA-S (Table 3).

Thus, the 4H^® and nitrile gloves gave complete protection regardless of what hair dye was used.  For the polyethylene and polyvinyl chloride gloves, respectively, complete protection was obtained against the HDp-ME-PPD but not against the other three hair dyes (Table 3, Figure 3).

No association was found for the polyvinyl chloride glove concerning the individual degree of patch test reactivity to PPD and the protective capacity, whereas with regard to 2,5-TDA-S reactivity, a numerical but not statistical association was indicated.

In a profession such as the hairdressers’ where there is a huge  exposure to both irritants and potentially contact allergic chemicals, the choice of gloves is of course important, and if advices can be based on evaluation simulating real life this is an obvious advantage. A method to  evaluate the performance of glove material could thus be through  in vivo studies mimicking the workplace exposure. In order to improve the advice given to hairdressers regarding protective gloves, we performed a study a few years ago 6 comparing the protective capacity of glove materials commonly used among hairdressers when exposed to a hair dye containing PPD. A good protection from nitrile gloves was noted. An interventional workplace-based study 11 concluded that when used correct, gloves can be protective in real work situations. Geens et al. 11 investigated the systemic exposure of hairdressers to 2,5-TDA-S and PPD using urine diamine biomarkers before and after ordinary work with permanent hair dyes the first week and again after providing nitrile gloves to hairdressers in the second week. Through the biomonitoring of PPD and 2,5-TDA-S a significant decrease of systemic exposure to 2,5-TDA-S but not to PPD was noted explained by the adequate use of nitrile gloves.

With regard to the exposure to hair dye ingredients, they vary qualitatively and quantitatively in different regions of the world. It is known that hair dyes in northern Europe more often contain 2,5-TDA or 2,5-TDA-S than PPD, or these dye ingredients combined 121314.  Furthermore, products bought in non-European countries usually contain higher concentrations of PPD 12. When comparing patch test results from dermatitis patients tested between 2003 and 2007 in 10 European patch test centres were compared, PPD sensitization occurred more often in Central and Southern Europe than in Scandinavia 15. The difference was thought to be due to the use of hair dyes with a darker shades more frequently. Moreover, a new hair dye substance, ME-PPD, was recently introduced in Europe 161718,  with  the aim to decrease the risk of sensitization and elicitation of allergic contact dermatitis.

In this study we wanted to further investigate the nitrile gloves that have already been found superior with regard to PPD 6 to evaluate them and other commonly used gloves for professional use and for home-dyeing, when using a PPD-, a 2,5-TDA-S- and a ME-PPD-containing hair dye for professional use and a 2,5-TDA-S-containing hair dye for home use. In order to get information on the hair dye products recommended for hairdressers during education and to collect information on how and to what degree protective measurements were taught, a visit in a school for apprentices hairdressers in Malmö was performed. Information on choice of gloves were collected also by performing a short interview with professional hairdressers, visiting 11 hairdressers’ saloons in the city of Malmö. The information was used to improve the actual study with regard to material used and time of exposure. In the study, where the aim was to evaluate gloves and hair dyes, a fixed time was decided. According to the outcome of our preliminary investigation including both hairdresser apprentices and professional hairdressers, we evaluated that a maximum exposure of 45 minutes in professional use and 30 minutes in the at-home dye condition was plausible.  

The performance of the polyethylene glove supplied in the package of a home-use hair dye was completely protective in all the subjects against the home-use hair dye, at 30 minutes of exposure, according to the instruction in the package. When the same glove was tested with professional hair dyes only (in 5 of the 7 individuals), its performance was poor most probably due to the increased exposure time (45 min).

Comparing the protection offered by the polyvinyl chloride gloves when using the different professional hair dyes, these gloves did not have a good performance  since 5 and 6 of 7 subjects reacted when tested with the HDp-PPD and with HDp-TDA-S respectively, and 5 of 7 subjects reacted at 30 minutes of exposure with HDhu-TDA-S.

With regard to polyvinyl chloride (tested in 7 subjects) and polyethylene (tested in 5 subjects)  with the HDp-ME-PPD, excellent protection was shown. On the other hand considering that the hair dye containing ME-PPD has recently been introduced on the market, we do not really know which reactivity pattern patients primarily sensitized to the ME-PPD would have. Therefore a larger group of individuals should be tested to verify if the good protection provided by the  gloves tested with this hair dye is due to a lower allergenic potential of the hair dye–ME-PPD-based. Previous patch testing with ME-PPD showed that there is decreased strength of elicitation response to this hair dye containing ME-PPD in PPD/TDA allergic subjects 17 and it has been shown that the hair dye products containing ME-PPD were tolerated by 29/43 PPD/TDA allergic individuals throughout continued hair dyeing with repeated treatments 18. In our study we could not patch test with dilution series of the substance as such and thus we have no knowledge of the actual reactivity pattern with regard to ME-PPD.  The two nitrile gloves gave complete protection with the three professional hair dyes at 45 minutes and with the home use hair dye at 30 minutes, comparable to the 4H^® glove (Figure 3, Figure 4, Figure 5), known to have excellent performance with regard to protection against chemicals 610.

In term of advice to hairdressers the study has shown that the nitrile glove must be the preferred choice during the hair dye procedures with the permanent hair dyes currently available. Also with regard to ME-PPD, nitrile gloves is easiest to advice since we know that these will protect the consumer. However limited, the study indicates that the use of hair dye for home use the gloves supplied in the package can be considered safe in term of hand exposure during the at-home dyeing procedure, taken into consideration that the exposure time is  limited to 30 minutes. Of course this does not prevent the at-home dye consumer or the person visiting the hairdresser from the risk of sensitization since the major risk is the actual hair dyeing in the individual case.