[The Abstract from the research article is=20
appended below the news story excerpt.]
* * *
http://www.latimes.com/news/nationworld/nation/la-na-ddt30sep30,0,3451847.st=
ory
Study suggests DDT, breast cancer link
Exposure in childhood is key, quintupling=20
the risk among women with high levels of the=20
pesticide, researchers say.
By Marla Cone, Los Angeles Times Staff Writer
September 30, 2007
Women heavily exposed to the pesticide DDT during=20
childhood are five times as likely to develop=20
breast cancer, a new scientific study suggests.
=46or decades, scientists have tried to determine=20
whether there is a connection between breast=20
cancer and DDT, the most widely used insecticide=20
in history. The UC Berkeley research, based on a=20
small number of Bay Area women, tested a theory=20
that the person's age during exposure was=20
critical, and provided the first evidence of a=20
substantial effect on breast cancer.
"There was very broad exposure to this pesticide,=20
and with this study, we have evidence that women=20
exposed when young were the most affected," said=20
Barbara A. Cohn, director of UC Berkeley's Child=20
Health and Development Studies, who led the study=20
of 129 women. "If this finding holds up, those=20
who were young and more highly exposed could be=20
the women at greatest risk."
Women born between 1945 and 1965 were most likely=20
to have been heavily exposed as children to DDT,=20
which was sprayed throughout the United States to=20
kill mosquitoes and other insects. DDT use began=20
in 1945, peaked in 1959 and was banned nationwide=20
in 1972 because it was building up in the=20
environment.
[=8A]
* * *
http://www.ehponline.org/realfiles/docs/2007/10260/abstract.html
Environmental Health Perspectives Volume 115, Number 10, October 2007
Research
DDT and Breast Cancer in Young Women: New Data on=20
the Significance of Age at Exposure
Barbara A. Cohn,1 Mary S. Wolff,2 Piera M. Cirillo,1 and Robert I. Sholtz1
1Child Health and Development Studies, Center for=20
Research on Women's and Children's Health, Public=20
Health Institute, Berkeley, California, USA;=20
2Mount Sinai School of Medicine, New York, New=20
York, USA
Abstract
Background: Previous studies of DDT and breast=20
cancer assessed exposure later in life when the=20
breast may not have been vulnerable, after most=20
DDT had been eliminated, and after DDT had been=20
banned.
Objectives: We investigated whether DDT exposure=20
in young women during the period of peak DDT use=20
predicts breast cancer.
Methods: We conducted a prospective, nested=20
case-control study with a median time to=20
diagnosis of 17 years using blood samples=20
obtained from young women during 1959-1967.=20
Subjects were members of the Child Health and=20
Development Studies, Oakland, California, who=20
provided blood samples 1-3 days after giving=20
birth (mean age, 26 years). Cases (n =3D 129)=20
developed breast cancer before the age of 50=20
years. Controls (n =3D 129) were matched to cases=20
on birth year. Serum was assayed for p,p=B4-DDT,=20
the active ingredient of DDT; o,p=B4-DDT, a low=20
concentration contaminant; and p,p=B4-DDE, the most=20
abundant p,p=B4-DDT metabolite.
Results: High levels of serum p,p=B4-DDT predicted=20
a statistically significant 5-fold increased risk=20
of breast cancer among women who were born after=20
1931. These women were under 14 years of age in=20
1945, when DDT came into widespread use, and=20
mostly under 20 years as DDT use peaked. Women=20
who were not exposed to p,p=B4-DDT before 14 years=20
of age showed no association between p,p=B4-DDT and=20
breast cancer (p =3D 0.02 for difference by age).
Conclusions: Exposure to p,p=B4-DDT early in life=20
may increase breast cancer risk. Many U.S. women=20
heavily exposed to DDT in childhood have not yet=20
reached 50 years of age. The public health=20
significance of DDT exposure in early life may be=20
large.
Key words: breast cancer, child health and=20
development studies, exposure timing, o,p=B4-DDT,=20
organochlorines, p,p=B4-DDE, p,p=B4-DDT, pregnancy,=20
premenopausal. Environ Health Perspect=20
115:1406-1414 (2007). [Online 24 July 2007]
*** NOTICE: In accordance with Title 17 U.S.C.=20
Section 107, this material is distributed,=20
without profit, for research and educational=20
purposes only. ***
