Image is of toys (not necessarily containing lead) from: http://www.flickr.com/photos/justanuptowngirl/2249080112/
Out of Harm’s Way:
Preventing Toxic Threats to
for Social Responsibility
•Scope of the problem of neurodevelopmental
& learning disabilities.
•Human vulnerability to toxic chemicals,
focusing on children.
• Current chemical environment, focusing on
mercury & pesticides in Oregon.
• What you can do to help your patients
“When an activity raises threats of harm
to human health or the environment,
precautionary measures should be
taken even if some cause and effect
relationships are not fully established
Wingspread Conference, 1998
•Total: 17%, 12 million children
•Learning disabilities: 5-10%
•One in eight Oregon children use
special education services
•Autism: 0.3- 0.66%; 1 in 150 young
$81.5 – $167 billion/yr - Neurodevelopmental deficits & related disorders.
$9.2 billion/yr - Attributable to
Over $8000/yr – Special education costs
for a child with autism.
$800 million/yr - OR special ed costs.
In June, 2008, the American Medical Association
issued a resolution stating that there was a need for
• To implement new, federal regulation to test and
update all chemicals in use today;
• To restructure the 1976 Toxic Substances Control Act
(TSCA) to effectively achieve these goals;
• To adopt safer production and uses of all
• To encourage the training of medical students,
physicians, and other health professionals about the
human health effects of toxic chemical exposures
with the help of the AMA.
The Significance of Small Effects
Example: population of 260 million
5 Point Decrease in Mean IQ
57% INCREASE IN
What causes developmental
Multiple factors interact in complex ways
during fetal development.
• Genetic traits &
• Exposure to toxins
• Social environment
Leonardo da Vinci
The result can be any
one or combination
of the traits and
behaviors we identify
Disorders (ASD) and
Embryonic Development &
Vulnerability of Vulnerability
Children are More Vulnerable to
• Eat, breathe & drink more per pound
• Mouth breathers
• Immature brain and blood-brain
• Gastrointestinal tract & skin have two
times the surface area of adults
• Outside more & closer to ground
• Hand-to-mouth behaviors
• Lower enzyme levels
Our Chemical Environment:
The State of Knowledge
• >81,000 chemicals, estimate
700 new chemicals/year.
• 62,00 chemicals
grandfathered in with no
• >4 billion lbs per year,
including 72 million lbs
Problem: Data available for just a few
chemicals. No data available for majority!
Lack of Testing for Developmental
Only 12 Tested for
According to EPA
THE TOXIC ICEBERG
NOT YET RECOGNIZED
• Adverse effects of toxins are
• Advisories based on analysis of a
single chemical are unlikely to
protect public health
Parental Concern vs.
i m c ti
Stickler GB, Simmons PS., Clin Pediatr 1995
parents worry "a lot"
Taking An Environmental
• Activities –
school, daycare, after
school, sports, grandparents, church, etc.
• Community – industry, agriculture, dump
site, water pollution, water source
• Household – dwelling, age, condition,
heating, sources, pesticides use, SHS
• Hobbies – arts, crafts, fishing
• Occupation – known exposures, fumes,
dusts, vapors, Material Safety Data
• Oral behaviors – pica/mouthing
Lead (Pb): a Persistent Problem
• Nationally: 2.2% have BLL predictive of lower IQ.
• New data: BLL<10 may reduce IQ proportionally
more than higher levels, affecting up to 16%
• Oregon: 2% homes high risk & 1% tested kids<6yo
have elevated BLL.
• Multnomah County: 4% homes high risk.
• Lead phase out: paint 70s; gas 80s; plumbing
• Lack of OR regulation: 19/48 industries air & 5/18
water have permits – we know nothing about
EXPOSURE – blood lead, ug/dl
THRESHOLD OF HARM - LEAD
Effects of Lead
on Cognitive and Behavioral
diff. w instructs
• Developmental effects:
– learning disabilities
– Lowered IQ
Chronic renal disease, nephritis
Reduced sperm count and libido
• Toys, plastic nipples and baby
• Old paint & water pipes
• Home renovation (in dust)
• Gasoline (soil contamination)
• Industrial/workplace emissions
• Hobbies-lead solder
• Bone release during pregnancy if
• Breast milk
• Costume jewelry & under-fired
• Folk remedies (greta, azarcon,
• Vinyl and non-glossy mini-blinds
• Regularly clean areas where children play;
• Clean/remove shoes outside;
• Limit use of toys, bottles & pacifiers which may
contain lead in paint or plastics, wash often;
• Test homes built before 1978, esp. if being
– Clean up paint chips, keep paint in good condition;
• Test drinking water & replace Pb solder-if
unable, use COLD water;
• Testing for all immigrants, Medicaid patients &
Call the Multnomah Co Lead Line 503-988-4000:
free tap water testing, BLL clinics, safe home
remodeling, risk assessment help
Coal-fired power plant in Cheshire, Ohio from http://www.flickr.com/photos/dshea/2089737103/
Methyl mercury (H3C-Hg+)
• Nationally: EPA estimates that 160 tons
• In Oregon: 4,500 lbs released from
human sources annually.
• Lack of OR regulation: 10 facilities
report Hg release, but Oregon does not
require emissions monitoring.
• Poisonings: Minamata 1950s & Iraq
• 5-8% of women of reproductive age
exceed recommended Reference Dose
(RfD) of 0.1mcg/kg/day.
• 50% of women who eat fish exceed RfD on
any given day.
• Higher risk: Children (estimated 300,000 per
year) of women with higher mercury intake;
Subsistence fishers, immigrants, Native
• Fish Advisories: in 2004, 44 states had over
2000 warnings; OR lists 16 water bodies with
Declining Threshold of Harm
Level associated with
(maximum safe exposure or high
end exposure from allowed fish
Benefits of Maternal Fish Consumption
Lessened by Mercury Exposure
Eat more fish with
Oken E et al., EHP 2005
Fish is a good food source:
- protein, iron, vitamin E,
selenium, and long chain n3 polyunsaturated fatty
Higher fish consumption
associated with improved infant
exposure (even very low dose)
associated with reduced
• Recommend children <6yrs and women of
child-bearing age avoid fish high in mercury.
• Provide pregnant women copies of Healthy Fish,
Healthy Families (PSR) and An Expectant
Mother’s Guide to Eating Fish in Oregon (DHS)
• Have car checked for mercury switches at
participating auto shop (free replacement with
• Use digital thermometers & thermostats.
• Recycle old mercury thermometers, thermostats
& compact fluorescent bulbs or tubes: 1-800RECYCLE
Guide to Healthy Fish
CHECK LOCAL AND STATE
FISH ADVISORIES at
• AVOID: Mackerel-King, Shark,
Swordfish, Tilefish; In OR, also
Bass (large & smallmouth),
• <2 servings/month (Hg &/or
PCBs): Salmon, Sardines,
• <1 serving/wk: Lobster, Tuna,
Orange Roughy, Grouper; In
OR, also Walleye, Carp,
How Much Fish is Safe?
IATP Fish Calculator
Enter your body
weight in pounds:
Select the species of
fish you eat:
Get your Results!
•Do not feed children swordfish,
shark, mackerel (King), and tilefish.
•“Chunk light” vs “solid white”
albacore (limit amt based on weight)
•Serve a variety of fish and seafood Haddock, pollock and shrimp are
among the low fat, low mercury
Pesticides: a Persistent Problem
• Definition: Physical, chemical or biological agent
intended to kill an undesirable plant or animal
• Major classes: insecticides, fungicides, herbicides.
• Market: in 1997, USA $11.9 billion & World $37
• History: new to humans & environment since
1940s; over 800 licensed as “active” ingredients
• Inherent toxicity: 140 pesticides considered
neurotoxic, 37 used on food &/or feed.
Pesticides and Health
Associations noted with:
– Neurodegenerative disorders
• Parkinson's Disease
– Birth defects
– Neurodevelopmental disorders
• Autism Spectrum Disorder (ASD)
• Attention Deficit and Hyperactive Disorder
Soft tissue sarcoma
• Same tumors repeatedly found in adult studies.
Zahm SH, Ward MH., EHP 1998
• Reported use: 98% of families, 80% during
• In Humans: detectable chlorpyrifos metabolites in
92% children’s, 82% adults’ urine.
• Food: detectable residues of at least 1 pesticide
on conventionally grown 72% fruits & vegetables.
• In Homes: 3 to 9 pesticide residues found; 70% of
infant levels from dust.
• In Air: indoor levels 10 to 100X higher than
• In Water: >90% stream samples, 50% of wells.
Occurrence and distribution of 11 types in surface &
ground water of the United States, 1992-97
Anthropological Study of
Children Exposed to Pesticides
Children from villages
practicing organic agriculture
Children from villages
Case: Transient Hypertonia in an
• 7lbs. 14 oz. term female, jaundice peak bili
• Normal physical exam at 12 weeks except
lower extremity and hypertonicity
• Pediatric consult at 16 weeks - upper and
lower extremity hypertonicity, ankle clonus
with diagnosis of cerebral palsy
• Physical therapy begun
• No environmental history was taken
Wagner SL, Orwick DL., Pediatrics 1994
Transient Hypertonia in an Infant
• Diazinon 1% sprayed by
unlicensed pesticide applicator
• Levels still high six months after
• Serum cholinesterase normal
• Urine metabolites high, similar to
post-shift urine of applicators
• Six weeks after removal from
house, muscle tone returned to
Wagner SL, Orwick DL., Pediatrics 1994
Urban Exposure to Pesticides
During Pregnancy Ubiquitous
• NYC women wore
backpack air samplers for
48 hrs during 3rd trimester
• 266/314 reported pest
measures at home (90%
• ALL tested positive for
exposure to at least 4
• Cord blood levels =
• Chlorpyrifos associated
with decrease in BW and
Whyatt et al. Envir. Health Persp. 2002
Organic Diet Reduces Exposure to
Common Agricultural Pesticides
• 23 children monitored for metabolites before/after organic
• Levels of urinary metabolites reduced to non-detectable
for malathion (left) and chlorpyrifos (right)
• Again elevated on re-introduction of conventional diet
Lu et al. 2006 EHP
Regularly clean areas where children play;
Practice Integrated Pest Management (IPM)
Use nontoxic products in yard;
Clean/remove shoes outside;
Buy organic food or, when unable, clean nonorganic produce;
• Store food in secure nontoxic containers.
• Select lawn care & pest control companies
which use IPM and nontoxic products.
Advice for Buying Organic:
Institute for Agriculture and Trade Policy
• The more we learn about chemicals, the
lower we shift the toxic “thresholds”.
• Subtle effects carry profound impacts
when expressed over a population (IQ).
• Adverse effects of toxins are often
synergistic-advisories based on analysis of
a single chemical are unlikely to protect
Disabilities are widespread. Toxic exposures
are preventable contributors.
Apparent toxicity at high doses is a red flag
for possible harm from low dose exposures.
Since “proof” of harm materializes slowly,
generations are being put at risk before
adequate regulatory response occurs.
To protect public health, we need a flexible
regulatory system capable of preventing (as
well as responding to) exposures.
What Can You Do?
• Be aware of
toxins & possible
exposures - use
Health Toolkit in
• Advocate for a
• Greater Boston
Physicians for Social
• Washington Physicians
for Social Responsibility
• Oregon Physicians for
• Ted Schettler, MD, MPH
• Steven G. Gilbert, PhD,
• Richard Grady, MD
• Catherine Thomasson,
• Michelle Gottlieb
• Jenny Pompilio, MD
• Maria Valenti
• Jill Stein, MD
• David Wallinga, MD
• Margie Kircher