Presentation at Massachusetts Green Careers Conference 2015

1. Kathryn Rodgers, MPH
Silent Spring Institute
www.silentspring.org
Massachusetts Green Careers Conference
October 1, 2015

2. Silent Spring Institute History
• Founded in 1994 by breast cancer activists to investigate
why breast cancer rates were higher on Cape Cod.
• Named in Rachel Carson’s legacy. “For those in whom cancer
is already a hidden or visible presence, efforts to find cures
must of course continue. But for those not yet touched by the
disease and certainly for the generations as yet unborn,
prevention is the imperative need.”

3. Research Areas
Study chemicals that are
mammary gland carcinogens
Study chemical exposures
from everyday products
Develop best practices for
sharing results with
community
Study endocrine
disrupting chemicals in
water sources
www.silentspring.or

4. Science to Action
We use our scientific expertise about chemicals that have
high exposure and high health concern to target best ways to
improve health.
www.silentspring.org

5. Cancer Prevention Science
Biological
mechanism
Human
exposure
Basis for
action
+
Educate
Regulate
Reformulate
Biological
mechanism
Human
exposure
Educate
Regulate
Reformulate
Strength of
evidence,
not “proof”
www.silentspring.or

6. How might chemicals increase breast cancer risk?
• Damaging DNA
Ionizing radiation
• Promoting tumor
growth
HRT
• Disrupting
development ->
vulnerability
DES
www.silentspring.or

7. Age-adjusted annual incidence rates for invasive breast
cancer at Kaiser Permanente Northwest
Glass, A. G. et al. J. Natl. Cancer Inst. 2007 99:1152-1161
Breast cancer
incidence dropped
when older women
went off HRT
Women < 45
45+
The WHI scenario resulted in 4.3 million
fewer cHT users, 126,000 fewer breast
cancer cases, 76,000 fewer cardiovascular
disease cases, 263,000 more fractures,
145,000 more quality-adjusted life-years,
and expenditure savings of $35.2 billion.
Roth et al. 2014
www.silentspring.or

8. 60+ years to develop
human evidenceof
breast cancer link Hoover et al, 2011
Prescribed to pregnant
women in 1940s-60s
Diethylstilbestrol (DES)
www.silentspring.or

9. Compounds Classified as
Group 1 via Population Studies:
Aflatoxins
Aristolochic Acid/Plants
Arsenic
Fluoro-edenite
Outdoor Air Pollution/PM
IARC
www.silentspring.or

10. Rodent MCs indicate likely breast carcinogens – consistent evidence
Rudel et. al 2014 Environmental Health
Perspectives
Exposure Human Breast
Cancer
Rodent Mammary
Tumors
HRT (E + P) + +
HRT (E) (+) +
Oral Contraceptives (E + P) + +
DES + +
Griseofulvin, Furosamide,
Metronidazole
(+) +
Indomethacin, Nitrofurantoin (-) +
Ionizing radiation + +
Alcohol + (+)
Heterocyclic amines (meat) (+) +
Sleep disruption (+) +
Ethylene oxide (+) +
PAH (+) +
Solvents (+) +
DDE (adult exposure) - -
DDT (early life exposure) (+) Not tested
PCBs (general population) - -
PCBs (polymorphism) (+) Not tested
Dioxin (early life exposure) (+) (+)
+
Stronger
evidence of
association
(+)
Limited
evidence of
association
(-)
Limited
evidence for no
association
-
Stronger
evidence for no
association
www.silentspring.org

11. Rudel et al. 2007
We compiled 216 rodent mammary carcinogens
www.silentspring.org/sciencereview
www.silentspring.or

12. Epidemiologists use the “breast cancer list”
to inform studies

13. www.silentspring.or

14. Revolution in toxicology – high throughput screening
96-, 384-, 1536
Well Plates
Target Biology
(e.g., Estrogen
Receptor)
Robots
Pathwa
y
Chemical
Exposure
Cell Population
EPA slide www.silentspring.org

15. www.silentspring.orgwww.silentspring.org

16. Cancer Prevention Science
Biological
mechanism
Human
exposure
Basis for
action
+
Educate
Regulate
Reformulate
Biological
mechanism
Human
exposure
Educate
Regulate
Reformulate
Strength of
evidence,
not “proof”
www.silentspring.or

17. Household Exposure Study
www.silentspring.or

18. Household Exposure Study – Cape Cod
Hypothesis: We will find EDCs and MCs from commercial
products in indoor environments at levels that reflect
significant exposures
Approach:
• New multi-residue methods for a large number of
chemicals
• Air, dust, and urine samples to identify exposure
pathways
www.silentspring.or

19. What are We Exposed To?
• About 20 chemicals per home
• 67 EDCs, 27 pesticides
• DDT 2/3 of homes
• Phthalates - 100% homes
• Parabens, alkylphenols - abundant
• Flame retardants – 10X Europe
levels
• 15 chemicals above health-based
guidelines (39 have guidelines)
• 100 of 120 homes above
health guidelines
• Participants want their results!
Rudel et al. 2003. Environmental Science & Technology www.silentspring.or

20. Household Exposure Study – California
Hypothesis: Indoor environments will be similar for most
commercial chemicals
Approach:
• Similar methods as in Cape Cod
• Demographically/geographically diverse population
• Paired indoor-outdoor air samples in two communities
with contrasting outdoor pollution
www.silentspring.org

21. 0
500
1000
1500
2000
2500
3000
3500
4000
Germany
(n=24)
2002
UK
(n=28)
2006
Canada
(n=68)
2002-2003
Cape Cod,
MA (n=89)
1999-2001
Boston, MA
(n=11)
2004-2005
Washington
DC (n=17)
2004
Texas
(n=20)
2006
California
(n=49)
2006
PBDEdustconcentrations(ng/g)
BDE 47
BDE 99
BDE 100
California PBDE dust levels 4
to 10 times higher than other
North American regions
California house dust has highest levels of PBDs
Zota et al. 2008. Environmental Science & www.silentspring.or

22. Blood PBDE levels in Californians nearly two fold higher
than rest of the U.S.
∑ PBDEs = sum of BDE-28, -47, -99,-100,-153, -154
0
10
20
30
40
50
60
70
80
California Other U.S. states
SPBDEserumconcentrations(ng/glipid)
p = 0.002
Zota et al., 2008 www.silentspring.orgZota et al. 2008. Environmental Science & Technology

23. California HES revisited: House dust levels 5 years later
• Hypothesis: Types and levels of flame retardants
will change because of phase-outs
Samples collected
in 2006 (n=50)
Indoor air – 153 analytes (3 FRs)
Outdoor air – 153 analytes (3 FRs)
House dust – 79 analytes (4 FRs)
Samples collected
in 2011 (n=16)
House dust – 62 analytes (49 FRs)
Revisited
www.silentspring.or

24. Many flame retardants detected, highest
concentrations were carcinogens
• 44 flame retardants detected; 36 in 50% of homes
• Chemicals with highest concentrations
2006 2011
TCEP* TBOEP
TCIPP TCIPP
TBOEP TCEP*
TDCIPP* TDCIPP*
BDE 99 BDE 99
*carcinogens under
California’s Proposition
65
Dodson et al. 2012. Environmental Science & Technology www.silentspring.or

25. Firemaster 550 levels increased in homes as it replaced
PentaBDE
www.silentspring.orDodson et al. 2012. Environmental Science & Technology

26. Cancer Prevention Science
Biological
mechanism
Human
exposure
Basis for
action
+
Educate
Regulate
Reformulate
Biological
mechanism
Human
exposure
Educate
Regulate
Reformulate
Strength of
evidence,
not “proof”
www.silentspring.or

27. Impact: Science and Policy
Science
• Flame retardants are among most abundant and most toxic home
exposures.
• Levels in California are among the highest in the world.
• Developed the most extensive methods to measure flame retardants.
• Sparked interest among researchers worldwide.
Policy
• High levels in California due to the state’s furniture flammability standard.
• Revision of California standard no longer requires flame retardants.
• Ban on PBDEs resulted in “regrettable substitutes”. Cited as a reason for
US to revise chemical safety laws.
• Our research supports changing local and national flame retardant
regulations.
www.silentspring.or

28. Thank you!
Visit www.silentspring.org