Report: Chemical mix may cause cancer
Tuesday 23 Jun 2015 4:11 p.m.
Chemicals
deemed safe to humans may blend lethally together inside the human body
to cause cancer, a high-profile scientific taskforce has ruled.
Researchers, including New Zealand scientist Dr
Linda Gulliver, have released findings into possible links between
common chemicals and the development of cancer.
Their results, published in the journal
Carcinogenesis, show mixtures of chemicals used in our environment may
be acting in concert with each other inside the body to trigger the
deadly disease.
Dr Gulliver, from Otago University's faculty of
medicine, says on the back of the findings of the Halifax Project,
"considerable attention" needs to be given to investigating the
concerning links.
The taskforce was formed in 2013 by the NGO Getting
to Know Cancer which had concerns that cancer research has focused
primarily on the role of heritable and lifestyle factors as triggers.
This is despite evidence that as many as one in five
cancers may be caused by chemical exposures in the environment that are
not related to personal lifestyle choices.
Chemicals
are tested for carcinogenic links but only one at a time, leaving
questions around the possibility that a fusion of these chemicals may
instead be causing cancer.
The taskforce of 174
scientists in 28 countries investigated 85 prototypic chemicals that
were not considered to be carcinogenic to humans, and they reviewed
their effects against a long list of mechanisms that are important for
cancer development.
Working in teams that focused
on various hallmarks of cancer, the group found that 50 of those
chemicals examined supported key cancer-related mechanisms at levels at
which humans are routinely exposed.
The finding
supports the idea that chemicals may be capable of acting in concert
with one another to cause cancer, even though low-level exposures to
these chemicals individually might not be carcinogenic.
Lead
researcher William Goodson III, from San Francisco's California Pacific
Medical Center, said his results show one-at-a-time testing is out of
date and must be modernised.
"Every day we are
exposed to an environmental 'chemical soup', so we need testing that
evaluates the effects of our ongoing exposure to these chemical
mixtures," he said.