40 years after exposure, Pesticide linked to higher breast cancer risk

DDT and Breast Cancer: Prospective Study of Induction Time and Susceptibility Windows

According to a recent study, DDT exposure before puberty may have increased the breast cancer risk for women in their 50s. Study is the latest to suggest early-life exposures, even prior to birth, may hold the key to understanding who gets diseases, Environmental Health News reports.

2019 Study Abstract

Background
In a previous Child Health and Development Studies report, p, p’-DDT was associated with a fivefold increased risk of premenopausal (before age 50 years) breast cancer for women first exposed before puberty. Here we extend our observation to breast cancer diagnosed during early postmenopause (ages 50–54 years) to determine whether age at diagnosis modifies the interaction of DDT with age at exposure.

Methods
We conducted a second prospective, nested case-control study in the Child Health and Development Studies (153 incident breast cancer cases diagnosed at ages 50–54 years and 432 controls matched to cases on birth year). These were analyzed separately and pooled with our previous study (129 breast cancer cases diagnosed at ages 31–49 years and 129 controls matched on birth year). Blood samples were obtained during pregnancy (median age, 26 years), 1–3 days after delivery from 1959 to 1967 in Oakland, California. Serum was assayed for p, p’-DDT, o, p’-DDT, and p, p’-DDE. Odds ratios (ORs) below are given for doubling of serum p, p’-DDT. All statistical tests were two-sided.

Results
For early postmenopausal breast cancer, p, p’-DDT was associated with risk for all women (ORDDT 50–54 = 1.99, 95% CI = 1.48 to 2.67). This association was accounted for by women first exposed to DDT after infancy (ORDDT 50–54 for first exposure after infancy = 2.83, 95% CI = 1.96 to 4.10 vs ORDDT 50–54 for first exposure during infancy = 0.56, 95% CI = 0.26 to 1.19; Pinteraction DDT x age at first exposure = .01). In contrast, for premenopausal breast cancer, p, p’-DDT was associated with risk among women first exposed during infancy through puberty, but not after (ORDDT<50 for first exposure during infancy = 3.70, 95% CI = 1.22 to 11.26, Pinteraction DDT x age at first exposure x age at diagnosis = .03).

Conclusions
p, p’-DDT was associated with breast cancer through age 54 years. Risk depended on timing of first exposure and diagnosis age, suggesting susceptibility windows and an induction period beginning in early life. DDT appears to be an endocrine disruptor with responsive breast targets from in utero to menopause.

Personal care product use and breast cancer risk

Associations between Personal Care Product Use Patterns and Breast Cancer Risk among White and Black Women in the Sister Study

New Research from USA NIEHS sister study of 47,000 women, suggests a link between frequent and moderate use of beauty products and breast cancer. The study reviews effects of environment and endocrine disruptors on risks of breast cancer and fibroids.

2018 Study Abstract

Background
Many personal care products include chemicals that might act as endocrine disruptors and thus increase the risk of breast cancer.

Objective
We examined the association between usage patterns of beauty, hair, and skin-related personal care products and breast cancer incidence in the Sister Study, a national prospective cohort study (enrollment 2003–2009).

Methods
Non-Hispanic black (4,452) and white women (n=42,453) were examined separately using latent class analysis (LCA) to identify groups of individuals with similar patterns of self-reported product use in three categories (beauty, skin, hair). Multivariable Cox proportional hazards models were used to estimate hazard ratios (HRs) and 95% confidence intervals (CIs) for associations between product use and breast cancer incidence.

Results
A total of 2,326 women developed breast cancer during follow-up (average follow-up=5.4y). Among black women, none of the latent class hazard ratios was elevated, but there were <100 cases in any category, limiting power. Among white women, those classified as “moderate” and “frequent” users of beauty products had increased risk of breast cancer relative to “infrequent” users [HR=1.13 (95% CI: 1.00, 1.27) and HR=1.15 (95% CI: 1.02, 1.30), respectively]. Frequent users of skincare products also had increased risk of breast cancer relative to infrequent users [HR=1.13 (95% CI: 1.00, 1.29)]. None of the hair product classes was associated with increased breast cancer risk. The associations with beauty and skin products were stronger in postmenopausal women than in premenopausal women, but not significantly so.

Conclusions
This work generates novel hypotheses about personal care product use and breast cancer risk. Whether these results are due to specific chemicals or to other correlated behaviors needs to be evaluated.

Breast-feeding Lowers Your Breast Cancer Risk

CDC’s Dr. Lisa Richardson explains why breastfeeding your babies can lower your risk of breast cancer

Watch Dr. Lisa Richardson, an oncologist and Director of the Division of Cancer Prevention and Control at CDC, explain why breastfeeding your babies can lower your risk of breast cancer.

Breast Cancer Differences in Young Women

Differences in breast cancer incidence among young women aged 20–49 years by stage and tumor characteristics, age, race, and ethnicity, 2004–2013

A recent CDC study highlights the differences in breast cancer incidence among young women. Although breast cancer is not common among younger women, rates have remained stable in recent years. Breast cancers in young women are more likely to be found at later stages and with more aggressive, larger tumors. Based on data from CDC’s National Program of Cancer Registries (NPCR) and the National Cancer Institute’s Surveillance, Epidemiology, and End Results (SEER) program, the study looked at breast cancer rates and trends by stage, grade, and tumor subtype, as well as age and race/ethnicity among women aged 20-49 years. From 2004-2013, the majority of invasive breast cancer cases (77.3%) occurred among women aged 40-49 years. Among women younger than 45 years old, black women had the highest breast cancer incidence. For women aged 45-49 years, white women had higher breast cancer incidence than black women. Across all age groups, incidence rates for triple-negative breast cancer were higher in black women than other races/ethnicities. These differences show that breast cancers in young women are highly diverse and in need of further research into personal and cultural factors. Take a look at our resource for triple-negative breast cancer.

Abstract

Purpose
Younger women diagnosed with breast cancer have poorer prognoses and higher mortality compared to older women. Young black women have higher incidence rates of breast cancer and more aggressive subtypes than women of other races/ethnicities. In this study, we examined recent trends and variations in breast cancer incidence among young women in the United States.

Methods
Using 2004–2013 National Program of Cancer Registries and Surveillance, Epidemiology, and End Results Program data, we calculated breast cancer incidence rates and trends and examined variations in stage, grade, and tumor subtype by age and race/ethnicity among young women aged 20–49 years.

Results
The majority of breast cancer cases occurred in women aged 40–44 and 45–49 years (77.3%). Among women aged < 45 years, breast cancer incidence was highest among black women. Incidence trends increased from 2004 to 2013 for Asian or Pacific Islander (API) women and white women aged 20–34 years. Black, American Indian or Alaska Native, and Hispanic women had higher proportions of cases diagnosed at later stages than white and API women. Black women had a higher proportion of grade III–IV tumors than other racial/ethnic groups. Across all age groups, incidence rates for triple-negative breast cancer were significantly higher in black women than women of other races/ethnicities, and this disparity increased with age.

Conclusions
Breast cancer among young women is a highly heterogeneous disease. Differences in tumor characteristics by age and race/ethnicity suggest opportunities for further research into personal and cultural factors that may influence breast cancer risk among younger women.

Is early detection always the best medicine ?

The Recommended Dose, with Alexandra Barratt

Hosted by acclaimed journalist and health researcher Dr Ray Moynihan, The Recommended Dose tackles the big questions in health and explores the insights, evidence and ideas of extraordinary researchers, thinkers, writers and health professionals from around the globe. The series is produced by Cochrane Australia and co-published with the BMJ.

Press Play > to listen to the recording.

Dr Ray Moynihan’s guest has led something of a double life, using both medicine and the media to explore and promote the critical role of evidence in healthcare. Now based at the University of Sydney, Alexandra Barratt‘s journey from clinician to journalist to global advocate for evidence based medicine and shared decision-making is a fascinating one.

Here Alexandra talks with Ray about her varied career and the reasons she’s ended up challenging conventional wisdom. She also talks about her research into the pros and cons of breast cancer screening and questions the widely-accepted idea that early detection is always the best medicine.

Our SoundCloud Playlists

Zeranol Use in Meat and Breast Cancer

Oestrogenic potencies of Zeranol, oestradiol, diethylstilboestrol, Bisphenol-A and genistein: implications for exposure assessment of potential endocrine disrupters

Anabolic growth-promoting drugs in meat production are by far the most potent hormones found in the food supply. Researchers have compared the oestrogenic potency of the synthetic oestrogen Zeranol, used as a growth promoter in meat production, and five related compounds, with the potency of 17beta-oestradiol, diethylstilboestrol (DES), genistein, and Bisphenol-A.

  • Care2 reports, April 20, 2018.
  • NutritionFacts reports, 25 Jul 2016.
Related Posts
Related Books
More DES DiEthylStilbestrol Resources

Less plastic use help decrease harmful chemicals in the body

The ReThink Plastic Pilot Study Community Report, 2018

A new pilot study has shown that women who reduce their exposure to plastic see a decrease in estrogen-mimicking chemicals in their bodies within a month.

The chemicals used in the manufacture of many plastics are known to mimic estrogen activity. There is strong scientific evidence linking these “environmental estrogens” to breast cancer. The ReThink Plastic study was designed to reduce exposure to these chemicals using simple, practical behavior change and to build a coalition of plastic use reduction by spreading the study messages. This approach could result in broad benefits by effectively reducing exposure to harmful chemicals in plastic and thus protecting against breast cancer and protecting the environment against plastic pollution.

Specifically, the objectives of the study were to:

  1. Inform participants about the harmful effects of chemicals that are in plastic
  2. Teach participants simple ways to reduce the use of plastic in order to reduce the potential for harmful health effects
  3. Ask participants to spread the message to other friends and family
  4. Evaluate the effectiveness of the study:
    • Examine changes in “plastic use” behavior before and after the study
    • Examine changes in estrogenic activity before and after the study in a small sub-study of post-menopausal women.

Reference.

Prenatal exposure to fracking chemicals linked to abnormal mammary glands in adulthood

Exposure to chemicals used during fracking may cause pre-cancerous lesions in mice, MU study finds

Environmental scientists at the University of Missouri and the University of Massachusetts observed changes in mammary gland development of female mice exposed during early development to the chemicals used in unconventional oil and gas (UOG) extraction – including fracking – at levels environmentally relevant to humans.

The Prenatal exposure to unconventional oil and gas operation chemical mixtures altered mammary gland development in adult female mice authors believe theirs is the first study to show that mouse mammary gland tissues are sensitive to a mixture of 23 commonly used UOG chemicals, with dose-specific effects on tissue morphology, cell proliferation and induction of intraductal hyperplasias, an overgrowth of cells considered a marker for future breast cancer risk.

2018 Study Abstract

Unconventional oil and gas operations (UOG), which combine hydraulic fracturing (fracking) and directional drilling, involve the use of hundreds of chemicals including many with endocrine disrupting properties. Two previous studies examined mice exposed during early development to a 23-chemical mixture of UOG compounds (UOG-MIX) commonly used or produced in the process. Both male and female offspring exposed prenatally to one or more doses of UOG-MIX displayed alterations to endocrine organ function and serum hormone concentrations. We hypothesized that prenatal UOG-MIX exposures would similarly disrupt development of the mouse mammary gland. Female C57Bl/6 mice were exposed to approximately 3, 30, 300 or 3000 μg/kg/day UOG-MIX from gestational day 11 to birth. Although no effects were observed on the mammary glands of these females prior to puberty, in early adulthood, females exposed to 300 or 3000 μg/kg/day UOG-MIX developed more dense mammary epithelial ducts; females exposed to 3 μg/kg/day UOG-MIX had an altered ratio of apoptosis to proliferation in the mammary epithelium. Furthermore, adult females from all UOG-MIX-treated groups developed intraductal hyperplasia that resembled terminal end buds, i.e., highly proliferative structures typically seen at puberty. These results suggest that the mammary gland is sensitive to mixtures of chemicals used in unconventional oil and gas production, at exposure levels that are environmentally relevant. The impact of these findings on the long-term health of the mammary gland, including its lactational capacity and its risk of cancer, should be evaluated in future studies.

Ask for More Research on Breast Cancer Prevention

Breast Cancer UK works to reduce breast cancer rates by tackling the environmental and chemical causes of the disease

Our lifestyles and our environment are potential contributors to disease. Diet, lack of exercise and exposure to environmental pollutants, including endocrine (hormone) disrupting chemicals (EDCs) present in many everyday products, may increase the risk of hormone related diseases such as breast cancer.

Sources

Endocrine Disruptors

More Information

Ask for Legislation to Reduce our Exposure to Endocrine Disrupting Chemicals

Breast Cancer UK works to reduce breast cancer rates by tackling the environmental and chemical causes of the disease

Our lifestyles and our environment are potential contributors to disease. Diet, lack of exercise and exposure to environmental pollutants, including endocrine (hormone) disrupting chemicals (EDCs) present in many everyday products, may increase the risk of hormone related diseases such as breast cancer.

Sources

Endocrine Disruptors

More Information