The construction of the Channel Tunnel is one of the largest civil eng
ineering projects ever undertaken. The British drive employed 5900 und
erground workers, and a number developed dermatitis during 1990/1991.
As a result, the Translink Joint Venture (TLJV) Medical Centre set up
a surveillance programme aiming to monitor and investigate the men wor
king closely with cement as well as other groups of workers with skin
problems. Men attended the Medical Centre voluntarily and were assesse
d, including history, examination and patch tests to a series of 15 te
st substances (from the European standard series) where indicated. A p
rogramme of education about the hazards of working with cement was ins
tituted, including leaflets, videos, local newspaper articles and pers
onal explanation by the Medical Centre staff. Between January 1990 and
January 1992, 1138 men were seen at the Medical Centre regarding thei
r skin and 332 were diagnosed as having occupational dermatitis, past
or present. Patch tests were performed on 180 men from all trades. Of
the 800 grouters, 466 (58 per cent) were assessed and 111 had a histor
y of occupational dermatitis at some time. Many gave a history of a si
ngle episode of dermatitis during a particularly hot and wet phase of
tunnelling. Patch tests performed on 86 grouters showed allergy to chr
omate in 56 (65 per cent). Of the 466 grouters assessed, 17 per cent h
ad positive patch tests to chromate but men with no skin problems past
or present were not patch tested. Cobalt allergy was often found with
chromate allergy (50 out of 56). Allergy to epoxy resin was also foun
d in 30 per cent of grouters who were patch tested. Only three men had
to change their occupation because of their skin disease. Most cases
of occupational dermatitis improved with regular medical supervision,
education and personal protective measures, with relocation to less ex
posed work where necessary. Many cases cleared as the tunnel entered b
etter terrain. The addition of ferrous sulfate has been shown to decre
ase the level of the allergenic hexavalent chromate in cement and its
compulsory use in Scandinavia has reduced the incidence of cement derm
atitis in construction workers. The rest of Europe should now follow t
he Scandinavian lead and consider legislation to make cement less haza
rdous to workers' health.