Environmental Health Sciences. Environmental Health Sciences John

Environmental Health SciencesEnvironmental Health Sciences


www.EnvironmentalHealthNews.orgwww.OurStolenFuture.org

www.ProtectingOurHealth.org

Environmental Health SciencesJohn Peterson Myers, Ph.D.John Peterson Myers, Ph.D.

Midstream in a Revolution Midstream in a Revolution Linking Environment and HealthLinking Environment and Health



Today’s epidemicsToday’s epidemics

Hormone-related cancers

Learning disabilities, ADHD

Pre-term birthObesity and diabetes

Asthma

Degenerative diseases

Infertility

Endometriosis

Autism


MIDSTREAM IN A MIDSTREAM IN A SCIENTIFIC REVOLUTIONSCIENTIFIC REVOLUTION

This scientific revolution is causing profound changes in how we think about the links between contamination and human health.


HEREDITY

ENVIRONMENTGENES

PHENOTYPE:What we become


HEREDITY

ENVIRONMENTGENES

Output of gene expression

PHENOTYPE:What we become


MIDSTREAM IN A MIDSTREAM IN A SCIENTIFIC REVOLUTIONSCIENTIFIC REVOLUTION

By the time it is complete and fully incorporated into public health and medicine, its impacts will be as profound as that wrought by Pasteur’s germ theory.


CONCEPTUAL SHIFTSCONCEPTUAL SHIFTS

Old…Old… a disease that is a disease that is linked to genes is a linked to genes is a disease under hereditary disease under hereditary control.control.New…New… a disease linked to a disease linked to genes is one vulnerable genes is one vulnerable to environmental causes. to environmental causes.



Old…Old… toxins work by toxins work by overwhelming the body’s overwhelming the body’s defenses…by brute force.defenses…by brute force.

New…New… toxins work by toxins work by hijacking control of gene hijacking control of gene expression. expression.



Parkinson’s:Parkinson’s:One of the hallmarks of PD is mid-One of the hallmarks of PD is mid-brain loss of dopaminergic neurons. brain loss of dopaminergic neurons.

Studies of families have linked Studies of families have linked some cases to specific gene some cases to specific gene mutationsmutationsNow research is focusing on what Now research is focusing on what may alter expression of specific may alter expression of specific genes important to keeping mid-genes important to keeping mid-brain neurons alivebrain neurons alive



Parkinson’s:Parkinson’s:

Studies of families have Studies of families have linked some cases to linked some cases to specific gene mutationsspecific gene mutations



New…New… impacts at impacts at everyday levels…everyday levels… levels people had levels people had become accustomed to become accustomed to calling “normal,” calling “normal,” background levels.background levels.

Old…Old… only high levels only high levels mattermatter


ARSENIC: high vs. lowARSENIC: high vs. low

At truly low At truly low levels levels ……

it interferes it interferes with hormone with hormone signalssignals

At high levels… it kills people

At moderately low levels… it causes a range of diseases



New…New… children and the children and the developing fetus are most developing fetus are most at riskat risk

Old…Old… focus on adults focus on adults


0.1

1

100

1,000,000

10,000

VULNERABLE STAGESVULNERABLE STAGES

PPBPPB

Recommended application level

Hermaphroditic frogs

Safe for drinking water

Safe short term

Rain anywhere

Rain

Hayes Hayes et alet al. 2002. 2002

ATRAZINEATRAZINE

Surface water

Run-off

Midwest streamsRivers



New…New… impacts at impacts at everyday levels…everyday levels…

levels people had become levels people had become accustomed to calling accustomed to calling “normal,” background “normal,” background levels.levels.

Old…Old… only high levels only high levels mattermatter


BACKGROUND LEVELSBACKGROUND LEVELS

Decrease immune function in Decrease immune function in toddlerstoddlers

Impair cognitiveImpair cognitive developmentdevelopment

Background PCBs/dioxin in Background PCBs/dioxin in Dutch mothersDutch mothers

Alter play behavior of children… Alter play behavior of children… boys engaging in less masculine boys engaging in less masculine behaviors and girls more behaviors and girls more feminine.feminine.


Bisphenol A exposure in Bisphenol A exposure in people at relevant levels is people at relevant levels is widespreadwidespread


Aneuploidy in peopleAneuploidy in people


What causes meiosis to What causes meiosis to lead to aneuploidy?lead to aneuploidy?


Bisphenol A causes Bisphenol A causes aneuploidyaneuploidy



Old…Old… the dose makes the the dose makes the poisonpoison

New…New… timing is crucial, timing is crucial, individual variation in individual variation in susceptibility important, and susceptibility important, and low doses can have effects low doses can have effects not predicted by high dose not predicted by high dose studies.studies.



Old…Old… immediate cause and immediate cause and effecteffect

New…New… long latencies long latencies following developmental following developmental exposure. exposure.

Fetal programming can Fetal programming can cause life-long impactscause life-long impacts


FETAL PROGRAMMINGFETAL PROGRAMMING

……fetal origins of adult diseasesfetal origins of adult diseases



Old…Old… take chemicals one take chemicals one at a timeat a time

New…New… essential to consider essential to consider the mixtures in which they the mixtures in which they alwaysalways occur occur


MIXTURES ARE THE RULEMIXTURES ARE THE RULE

210 chemicals sampled:

Baltz: 106Brody: 85Hardin: 77Lerner: 101Martin: 95Moyers: 84Patton: 105Rome: 86Waletzky: 78



Old…Old… traditional health traditional health endpoints... mutagenicity, endpoints... mutagenicity, carcinogenicity, cell deathcarcinogenicity, cell death

New…New… erosion of cognitive, erosion of cognitive, immunological and immunological and reproductive function. reproductive function.


0

5

10

15

20

25

PCB E-B Virus PCB+EBV

LowHighR

isk

rati

o

Rothman et al. 1997

NON-HODGKINS LYMPHOMANON-HODGKINS LYMPHOMA

Interaction between contaminant and virus


HEALTH QUESTIONS HEALTH QUESTIONS ABOUT BISPHENOL AABOUT BISPHENOL A

Aneuploidy

Prostate cancer

Impaired brain development

Long-term memory formation

Weight control and obesity

Low sperm count



Old…Old… a small number of bad a small number of bad actorsactors

New…New… many chemicals many chemicals implicated we thought were implicated we thought were safe. safe.


THE BAD ACTORSTHE BAD ACTORS

Old… Old… DDT, PCBs, dioxin, lead, DDT, PCBs, dioxin, lead, mercury and many moremercury and many more

New…New… “modern-use” “modern-use” pesticides likepesticides like atrazine, atrazine, plastics likeplastics like bisphenol A, bisphenol A, additives to plastics likeadditives to plastics like phthalates, brominated flame phthalates, brominated flame retardants, retardants, surfactants likesurfactants like nonylphenol.nonylphenol.


BAD NEWS, GOOD NEWSBAD NEWS, GOOD NEWS

Bad news…Bad news…

Widespread exposure to Widespread exposure to compounds that interfere compounds that interfere with gene expression, with gene expression, sometimes at extremely low sometimes at extremely low levels. levels.



Good news…Good news…

A disease under genetic A disease under genetic control may be one caused control may be one caused by environmental by environmental exposures.exposures.We will have the opportunity We will have the opportunity to prevent many diseases to prevent many diseases that heretofore have not that heretofore have not been perceived as been perceived as preventable.preventable.



Good news…Good news…

A disease under genetic A disease under genetic control may be one caused control may be one caused by environmental by environmental exposures.exposures.We have shown with lead We have shown with lead and POPs that society can and POPs that society can decrease exposures once it decrease exposures once it reaches political consensusreaches political consensus


1974 1980 1986 1992

4

8

12

16

Blo

od

lead

levels

(m

g/d

L)

Blo

od

lead

levels

(m

g/d

L)

0

1998

Blood lead levels in the U.S.

YearYearSource: CDC. National Report on Human Exposure to Environmental Chemicals, March 2001


NEXT CHALLENGENEXT CHALLENGE

Identifying compounds that interfere with gene expression

Collaborative for Collaborative for Health and the EnvironmentHealth and the Environment

Incorporating this scientific revolution into a new generation of health standards


Today’s epidemicsToday’s epidemics

Hormone-related cancers

Learning disabilities, ADHD

Pre-term birthObesity and diabetes

Asthma

Degenerative diseases

Infertility

Endometriosis

Autism



Web resourcesWeb resources

www.ProtectingOurHealth.org

www.OurStolenFuture.org

www.EnvironmentalHealthNews.org

Documents

Environmental Health Sciences. Environmental Health Sciences John