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. | No |
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