In 2011, the styrene, a high volume plastics chemical and animal
carcinogen, was the focal point in a 'poison scandal' in the Danish
media; but now a registry study of more than 72,000 employees from more
than 400 companies that have been exposed to styrene during production
of glass fiber reinforced plastics, has not found an increased incidence
of a wide range of cancer types. The Department of Occupational Medicine
at Aarhus University is behind the study.
Employees in the glass fiber reinforced plastics who have worked
with the chemical styrene do not have - as previously feared - an
increased incidence of cancer of the esophagus, pancreas, lungs,
kidneys, bladder or a wide range of other types of cancer. On the other
hand, they may possibly have an increased risk of developing what is
known as myeloid leukemia and nasal and paranasal cancer.
This is the conclusion of the most comprehensive study so far, which
has been prepared by the Department of Occupational Medicine at Aarhus
University. The study was recently published in the American scientific
. It covers 72,292 employees who worked for
one of the 443 small and medium-sized companies in Denmark that have
used styrene for the production of e.g. wind turbines or pleasure boats
during the period 1968-2012.
The Danish survey was initiated by a 'poison scandal' back in 2011,
where the Danish newspaper Berlingske Tidende gave voice to 20 former
employees of the company LM Wind Power in Lunderskov near Kolding
(formerly LM Glasfiber). All of the employees were seriously ill,
allegedly due to interaction with styrene, which was used in windmill
They reported everything from inflamed boils the size of golf balls
to respiratory problems, memory loss and fear of cancer, providing what
was - together with the subsequent political debate, including
discussions about completely prohibiting styrene - an obvious starting
point for investigating the long-term effects, explains professor at the
Department of Occupational Medicine at Aarhus University, Henrik A.
"Via several national registers we have identified the relevant
companies and their employees, before coupling this information with the
Danish Cancer Register. We have thus compared occurrences of different
types of cancer in 72,000 employees, against the risk of these diseases
in the general population who have not come into contact with styrene,"
says Henrik A. Kolstad.
"It is important to know for present and former workers exposed to
styrene that they are unlikely to have become ill by doing their job, if
they have developed cancer of the oesophagus, pancreas, lungs, kidneys,
bladder or a wide range of other types of cancer. This is also new and
important knowledge in the USA, where styrene was added to the list of
carcinogenic substances in 2011," says Henrik A. Kolstad.
In relation to the types of cancer where the study shows a possible
increased risk, i.e. nasal and paranasal cancer and myeloid leukaemia,
Henrik A. Kolstad emphasises that more investigation needs to be done to
determine if styrene is the actual cause of the employee's disease.
This must now be verified with detailed studies of the employees who
have become ill, for example by elucidating if they were directly
involved in the production and the styrene levels they were exposed to.
Henrik A. Kolstad emphasises that the sins of the past are the focal
point here, and that the working environment has changed significantly
since then, so that work with styrene in the reinforced plastics
industry in Denmark today takes place in closed spaces with strict
exhaust ventilation requirements. As a researcher he also rejects the
idea that people can 'just' use alternatives to styrene. This was a view
that some of LM Wind Power's competitors promoted when the criticism of
the company was at its highest:
"It is a case of risk assessment: Should you use styrene, which
might have serious - though unconfirmed - side effects in the form of
cancer, or should you use epoxy products, which has less serious but
well-documented side effects in the form of eczema?" as Henrik A.
Kolstad puts it. He expects the follow-up research results to be ready
during the spring of 2017.