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Out of Harm’s Way: Preventing Toxic Threats to Child Development. Oregon Physicians for Social Responsibility October 2007 www.oregonpsr.org. Today’s Presentation. Scope of the problem of neurodevelopmental & learning disabilities. - PowerPoint PPT Presentation
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Out of Harm’s Way: Preventing Toxic Threats to Child Development
Oregon Physicians for Social ResponsibilityOctober 2007
www.oregonpsr.org
•Scope of the problem of neurodevelopmental & learning disabilities.
Human vulnerability to toxic chemicals, focusing on children.
Current chemical environment, focusing on lead, mercury & pesticides in Oregon.
What you can do to help your patients minimize and, ideally, prevent exposures.
Today’s Presentation
Prevalence of Learning and Behavioral Disabilities
Total: 17%, 12 million children
• Learning disabilities: 5-10%
• ADHD: 1-20%
• Autism: .3-.66%
Reported Trends: Real? Better reporting? Changing criteria?
Learning disabilities
191% Special Ed: 1977-1994
ADHD 1- 20% Reported prevalence
>800% Ritalin since 1971
Economic Implications
$81.5 – $167 billion/yr: Neurodevelop-mental deficits & related disorders.
$9.2 billion/yr: Attributable to environmental pollutants.
$80-100,000/yr: Residential treatment for a child with autism.
$800 million/yr: OR special ed costs.
NUTRITION
Traits/ Abilities
DevelopmentalSyndromes
ADHD Autism
Learning disability
SOCIAL ENVIRONMENT
GENETICS
Framework for Understanding
NUTRITION
Asperger’s syndrome
TOXICANTS
???
Embryonic Development & Vulnerability
Children are More Vulnerable to All Toxins
Eat, breathe & drink more per lb; Mouth breathers; Immature brain, blood/brain barrier; GI & skin 2x surface area vs adult; Outside more & closer to ground; Hand/mouth behaviors; Lower enzyme levels.
The Significance of Small Effects: EFFECTS OF A SMALL SHIFT IN IQ DISTRIBUTION IN A
POPULATION OF 260 MILLION
160140120100806040
70 130I.Q.
mean 100
6.0 million "gifted"
6.0 million "mentally retarded"
5 Point Decrease in Mean IQ just one IQ point drop ~ 2.4% reduction in lifetime earnings
160140120100806040
mean 95
70 130
2.4 million "gifted"
9.4 million "mentally retarded"
57% INCREASE IN
"MentallyRetarded”Population
I.Q.
Our Chemical Environment: The State of Knowledge
>82,000 chemicals. est. 700 new chemicals/year. >4 billion lbs per year, inc. 72 million lbs carcinogens. Basic Screening Information Data Set (SIDS) ~$205,000/chemical.
Problem:Problem: Data available for just a few chemicals. No data available for majority!
Developmental Testing of Chemicals Produced @ > 1 million lbs/year
33.1%
0.4%
78.2%
No DataOn DevelopmentalToxicity
Only 12 Tested for NeurodevelopmentalToxicityAccording to EPAGuidelines
Some DataOn DevelopmentalToxicity
PROVEN HARM
PARTIALLY PROVEN
NOT YET RECOGNIZED
FOREVER UNRECOGNIZED
THE TOXIC ICEBERG
lead
0.1
1
10
100EX
PO
SU
RE –
blo
od
lead
, u
g/d
l
DECLINING THRESHOLD OF HARM - LEAD
ReportedHarm (CDC)
?New Level?
YEAR REPORTED
1960 1970 1980 1990 2000
Lead (Pb): a Persistent Problem
Nationally: 2.2% have BLL predictive of lower IQ. New data: BLL<10 may reduce IQ more than higher
levels, affecting up to 16% children. 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 1985. Lack of OR regulation: 19/48 industries air & 5/18
water have permits – we know nothing about the rest. Increase in immigrants
ADHD LD OTHER
hyperactivity reading, math fine motor impulsivity spelling visual motor distractibility pattern recognition aggressive dif. w. instructs word recognition antisocial conduct problems off-task executive function attention/vigilance social skills
Effects of Lead on Cognitive and Behavioral Traits
Other Health Effects of Lead Exposure
Chronic renal disease, nephritis Dementia atherosclerosis Peripheral neuropathy Behavioral changes Reduced sperm count and libido Miscarriages Hypertension
Sources of Lead
Old paint & water pipesHome renovation (in dust)Gasoline (soil contamination and bio-accumulation in
root>stem>leafy vegetables)Industrial/workplace emissionsHobbies-lead solder Bone release during pregnancy if calcium deficientBreast MilkCostume jewelry & under-fired terra cottaMexican folk remediesVinyl and non-glossy mini-blinds
Advise Patients
Clean up paint chips, keep paint in good condition; Regularly clean areas where children play; Wash toys, stuffed animals, bottles & pacifiers often; Clean/remove shoes outside; Test homes built before 1978, esp. if being remodeled Test drinking water & replace Pb solder-if unable, use
COLD water. Testing for all immigrants, Medicaid patients & low SES Call the Multnomah Co Lead Line 503-988-4000: free tap water testing, BLL clinics, safe home remodeling,
risk assessment help
Mercury (Hg): a Persistent Problem
Poisonings: Minamata 1950s & Iraq 1971. Nationally: EPA est.160 tons released annually. In Oregon: 4,500 lbs released from human
sources annually. Lack of OR regulation: 10 facilities report Hg
release-none required to monitor emissions by state.
The Mercury Cycle
Sources of Mercury
Industrial emissionsMunicipal & medical
incineratorsAbandoned Hg & gold
minesNatural off-gassing Dental amalgamsBioaccumulation in
foodsOld thermometers, BP
cuffs & auto switches
Health Effects of Mercury
Cerebral palsy MR/DD balance problems hearing loss/deafness visual impairment/blindness peripheral neuropathy seizures abnl reflexes & muscle tone Psychiatric disturbances
Mercury Exposures
5-8% of women of reproductive age exceed recommended Reference Dose (RfD) of 1ug/kg/day.
50% of women who eat fish exceed RfD on any given day.
Higher risk: Children of women with higher Hg intake (est. 300k/yr); Subsistence fishers, immigrants, Native Americans.
Fish Advisories: in 2004, 44 states had >2k warnings; OR lists 16 water bodies.
Mercury:Declining Threshold of Harm
20001990198019700.01
0.1
1
10
100
YEAR
Level associated with
harmful effectRegulatory standard
(maximum safe exposure or high end exposure from allowed fish
contamination)
FDA WHO
EPA
ATSDR
DA
ILY
IN
TA
KE
(mic
rogr
ams/
kg/
day
Hg)
Benefits of Maternal Fish Consumption Lessened by Hg Exposure
Fish is a good food source: protein, iron, vitamin E, selenium, and
long chain n-3 polyunsaturated fatty acids Higher fish consumption associated with
improved infant cognition However...Higher Hg (even very low dose)
associated with reduced cognition
Eat more fish with less mercuryOken E et al., EHP 2005
Advise Patients
Have car checked for Hg switches at participating auto shop (free replacement w/nonHg switch).
Use digital thermometers & thermostats.
Recycle old Hg thermometers, thermostats & fluorescent light tubes: 1-800-RECYCLE
Provide pregnant women copies of Healthy Fish, Healthy Families (PSR) and An Expectant Mother’s Guide to Eating Fish in Oregon (DHS)
Recommend children <6yr and women of child bearing age avoid fish high in mercury.
Guide to Healthy Fish
AVOID: Mackerel-King, Shark, Swordfish, Tilefish; In OR, also Bass (large & smallmouth), Brown Trout.
<2 servings/month (Hg &/or PCBs): Salmon, Sardines, Herring, Bluefish.
<1 serving/wk: Lobster, Tuna, Mackerel-Spanish, Marlin, Orange Roughy, Grouper; In OR, also Walleye, Carp, Catfish, Sturgeon.
CHECK LOCAL AND STATE FISH ADVISORIES at
www.healthoregon.org/fishadv
How Much Fish is Safe?
•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 choices.
Enter your body weight in pounds:
Select the species of fish you eat:
Get your Results!
IATP Fish Calculator
www.iatp.org
Pesticides: a Persistent Problem
Definition: Physical, chemical or biological agent intended to kill an undesirable plant or animal pest.
Major classes: insecticides, fungicides, herbicides. Market: in 1997, USA $11.9 billion & World $37 billion. History: new to humans & environment since 1940s; over
800 licensed as “active” ingredients by EPA. Inherent toxicity: 140 pesticides considered neurotoxic,
37 used on food &/or feed.
Organophosphate Pesticides
Occurrence and distribution of 11 types in surface & ground water of the United States, 1992-97
http://ga.water.usgs.gov/publications/abstracts/ofr00-187.html
Pesticides and Children
Associations noted with:– Neurodegenerative disorders
Parkinson's Disease– Birth defects– Neurodevelopmental disorders– Leukemia – Non-Hodgkin’s lymphoma– Soft tissue sarcoma– Brain tumors
Same tumors repeatedly found in adult studies.
Zahm SH, Ward MH., EHP 1998
Background Pesticide Exposures Widespread
Reported use: 98% of families, 80% during pregnancy. In Humans: detectable chlorpyrifos metabolites in 92%
children’s, 82% adults’ urine. Food: detectable residues of at least 1 pesticide on 72%
fruits & vegetables (not sustainably grown). In Homes: 3 to 9 pesticide residues found; 70% of infant
levels from dust. In Air: indoor levels 10 to 100X higher than outdoor air. In Water: >90% stream samples, 50% of wells.
Pesticides: the Health EffectsYaqui Indian Pesticide - Anthropomorphic Study
Organic Diet Reduces Exposure to Common Agricultural Pesticides
23 children monitored for metabolites before/after organic diet Levels of urinary metabolites reduced to non-detectable for
chlorpyrifos and malathion Again elevated on re-introduction of conventional diet
Advise Patients
Regularly clean areas where children play; Use IPM and nontoxic products in yard; Clean/remove shoes outside; Buy organic food or, when unable, clean
non-organic produce; Store food in secure nontoxic containers. Select lawn care & pest control companies
which use IPM and nontoxic products.
Advice for Buying OrganicPesticide Report Card
Environmental Working Group www.ewg.org
Emerging Themes
The more we learn about chemicals, the lower the toxic thresholds tend to fall.
Animal testing for NDT underpredicts human vulnerability by a factor of 100 to 10,000.
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 public health.
Conclusions
Guiding Principles
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.
Conclusions
Be aware of environmental toxins & possible effects. Provide education on prevention and minimizing
exposures. Additional resources, incl. research articles and patient fact sheets, available at www.oregonpsr.org
Incorporate the Pediatric Environmental Health Toolkit into your practice:
http://psr.igc.org/ped-toolkit-materials.htm Advocate for a healthier environment:
www.envirohealthaction.org
Conclusions
What Can You Do??
“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 scientifically.”
Wingspread Conference, 1998.
Precautionary Principle
Breastfeeding is Best for Baby
Taking An Environmental History
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, fishingOccupation – known exposures, fumes, dusts,
vapors, Material Safety Data Sheets
Oral behaviors – pica/mouthing
Strategies to Reduce Lead Pollution in Oregon
Policy Solutions: Remediate Pb paint in homes & apartments. Act on Blood lead level >2. Ensure all Medicaid children tested for BLL. Test schools & child care facilities for Pb paint &
drinking water. Ensure recycling of Pb products (batteries &
computer monitors). Require DEQ to set permit limits for industrial
release of Pb.
Strategies to Reduce Mercury Pollution in Oregon
Policy Solutions: Mercury Solutions Act 2001 Eliminate Hg from industrial equipment Recycle Hg products (fluorescent light tubes) Clean up mines and Superfund sites Reduce Hg from dental offices, labs & health care
facilities (OCEH-HCWH/H2E) Include Hg in applicable DEQ air & water permits Mandate point sources adopt Clean Air Act
technologies Implement Oregon’s Executive Order
Strategies to Reduces Exposure to Home & Garden Pesticides in Oregon
Policy Solutions: Oregon’s pesticide use reporting system (1999)
finally funded. Educate homeowners re: non/low toxic options. Encourage schools, childcare facilities & local
governments to use Integrated Pest Management (IPM), i.e. Pesticide Free Parks.
Encourage pet owners to use flea combs and vacuuming to control fleas.
Ask retailers to educate customers about safer alternatives and IPM.
Acknowledgments
Greater Boston Physicians for Social Responsibility Washington Physicians for Social Responsibility Ted Schettler, MD, MPH Steven G. Gilbert, PhD, DABT Richard Grady, MD Catherine Thomasson, MD Michelle Gottlieb Maria Valenti Jill Stein David Wallinga, MD