Breast cancer risk and exposure to organochlorine
insecticides: consideration of the epidemiology data on dieldrin,
DDT and certain hexachlorocyclohexane isomers
COC statement COC/04/S3 - September 2004
Overview of the COC statement
The COC has finalised its evaluation of whether a number of organochlorine
insecticides may cause breast cancer. The Committee evaluated the hypothesis
that organochlorine insecticides might increase the risk of breast cancer
by virtue of their claimed oestrogenic effects. Thus, if a particular
chemical had no oestrogenic activity in vivo, then there was no
rationale as to why it could be considered as a risk factor for breast
cancer. A summary of the main conclusions is given below. The Committee
has published both a detailed technical statement and a non-technical
summary. You should read either of these documents to obtain information
on the Committee's conclusions and how they were derived.
To supplment the statement and non-technical summary, the Committee have
published detailed tabular presentations of all the studies considered
and summary graphs depicting the results of the epidemiology studies.
These documents serve as background information.
Conclusions on the individual chemicals considered in the 2003/4 review
OCI
Does the chemical have oestrogen-like effects
in animals?
Are the levels detected in human tissue significant?
What is the relationship between human exposure
to a particular OCI and breast cancer?
Are people who are exposed to environmental
levels of a particular OCI at increased risk of developing breast
cancer?
DDT
Yes, although its effects are very weak.
Levels of DDT are known to be declining.
There is no evidence for a link.
No
Dieldrin
No
Levels of dieldrin are known to be declining.
Overall there is insufficient information to draw any conclusions.
No definite conclusions drawn. To be kept
under review.
Beta-HCH
Yes, although its effects are very weak.
Levels of Beta-HCH are known to be declining.
Overall there is no evidence for a link.
No
Lindane
No
No
Overall there is insufficient information
to draw any conclusions.
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