EPI NEWS
Oct 15, 2006—Workers involved in the product-
ion of synthetic rubber goods are exposed to
several carcinogens, but industry and academ-
ic researchers have been at odds over the
health costs of these exposures. Past reviews
of published studies have identified elevated
risks for lung cancer, bladder cancer, stomach
cancer, and leukemia among rubber workers.
Now, authors of a chemical industry-sponsored
meta-analysis of worker mortality data from 31
previously published studies say that rubber
workers might have a lower overall risk of dying
from most cancers than is the case for the gen-
eral public. However, the team also confirmed a
significant excess in worker mortality due to
leukemia (American Journal of Epidemiology
2006;164:405-420).
The meta-analysis team, led by Nicola Alder of
the Center for Statistics in Medicine at Oxford
University and Alexander Sutton of the Univer-
sity of Leicester School of Medicine, also re-
ported increased diabetes death rates among
rubber industry workers.
The study's failure to confirm previously report-
ed associations between rubber factory work
and cancers other than leukemia should be
interpreted with caution, admit the researchers.
A "healthy worker" effect often confounds
comparisons of workers and the general public,
for example.
“We usually expect the mortality rate to be
lower in employed populations,” explains Hal
Morgenstern of the University of Michigan, who
was not involved in the meta-analysis.
Oct 15, 2006—Workers involved in the product-
ion of synthetic rubber goods are exposed to
several carcinogens, but industry and academ-
ic researchers have been at odds over the
health costs of these exposures. Past reviews
of published studies have identified elevated
risks for lung cancer, bladder cancer, stomach
cancer, and leukemia among rubber workers.
Now, authors of a chemical industry-sponsored
meta-analysis of worker mortality data from 31
previously published studies say that rubber
workers might have a lower overall risk of dying
from most cancers than is the case for the gen-
eral public. However, the team also confirmed a
significant excess in worker mortality due to
leukemia (American Journal of Epidemiology
2006;164:405-420).
The meta-analysis team, led by Nicola Alder of
the Center for Statistics in Medicine at Oxford
University and Alexander Sutton of the Univer-
sity of Leicester School of Medicine, also re-
ported increased diabetes death rates among
rubber industry workers.
The study's failure to confirm previously report-
ed associations between rubber factory work
and cancers other than leukemia should be
interpreted with caution, admit the researchers.
A "healthy worker" effect often confounds
comparisons of workers and the general public,
for example.
“We usually expect the mortality rate to be
lower in employed populations,” explains Hal
Morgenstern of the University of Michigan, who
was not involved in the meta-analysis.
Industry Study Confirms Excess Leukemia in Synthetic Rubber Workers
First published meta-analysis of mortality rates finds elevation in diabetes as well
First published meta-analysis of mortality rates finds elevation in diabetes as well
“Employed populations are employed in part
because they are healthy and less likely to
die in the next several years.”
Such comparisons can therefore create
artificially rosy pictures of disease rates
among workers, Morgenstern says.
Another problem, researchers tell epiNews, is
that mortality rates are less sensitive and
reliable for detecting disease risks than are
rates of disease diagnoses. Death certificat-
es often fail to mention underlying chronic
diseases that gave rise to the immediate
cause of death.
The authors of the meta-analysis acknowl-
edge methodological problems, but reiterate
the failure of their analysis to confirm prev-
iously identified connections between rubber
factory work and cancers other than leukemia.
"Overall the mortality experience of workers
in the rubber industry is similar to or better
than that of the general population," they
report. "We found an excess of leukemia in
cohorts manufacturing rubber goods other
than tires that was potentially associated with
exposure to benzene and/or 1,3-butadiene."
Contacted by email, the authors declined to
comment further on their findings.
The study was funded by the American
Chemistry Council, whose Advisory Panel
"gave advice throughout the project."
because they are healthy and less likely to
die in the next several years.”
Such comparisons can therefore create
artificially rosy pictures of disease rates
among workers, Morgenstern says.
Another problem, researchers tell epiNews, is
that mortality rates are less sensitive and
reliable for detecting disease risks than are
rates of disease diagnoses. Death certificat-
es often fail to mention underlying chronic
diseases that gave rise to the immediate
cause of death.
The authors of the meta-analysis acknowl-
edge methodological problems, but reiterate
the failure of their analysis to confirm prev-
iously identified connections between rubber
factory work and cancers other than leukemia.
"Overall the mortality experience of workers
in the rubber industry is similar to or better
than that of the general population," they
report. "We found an excess of leukemia in
cohorts manufacturing rubber goods other
than tires that was potentially associated with
exposure to benzene and/or 1,3-butadiene."
Contacted by email, the authors declined to
comment further on their findings.
The study was funded by the American
Chemistry Council, whose Advisory Panel
"gave advice throughout the project."
Statistical details Pooled odds ratios Diabetes, rubber factory work: OR 1.36, CI:1.17,1.59 (5 cohorts) Leukemia, rubber factory work : OR 1.21, CI:1.03,1.43 (16 cohorts) |