Children's Health (21) Flashcards
**1904, Queensland Australia
lead poisoning in young children exposed to lead-based paint
**Herbert Needleman:
identified subclinical effects of lead associated with low environmental exposures including loss of intelligence and disruptive behavior
**What event established that infants and fetuses are more susceptible than adults to radiation-induced leukemia?
Leukemia among young children exposed to ionizing radiation in the 1945 atomic bombing of Hiroshima and Nagasaki.
**Chemical involved in Minamata, the results of exposure to it, and what type of exposure led to the most severe effects:
methylmercury
cerebral palsy, mental retardation, convulsions
in utero exposure
result of thalidomide (anti-nausea drug) ingestion during early pregnancy
phocomelia (limb malformation)
result of women exposed in utero to diethylstilbestrol to prevent premature labor
vaginal adenocarcinoma
**NRC 1993 Report:
“Diets of Infants and Children”
**Act passed in 1996:
Food Quality Protection Act
**National Children’s Study in 1997:
Executive Order on Children’s Health and the Environment
**Act passed in 2008:
Consumer Product Improvement Act
**Number of chemicals produced since the 1950s
nearly 80,000
Number of synthetic chemicals classified as high production volume (HPV)
2800
Percentage of HPV synthetic chemicals tested for toxicity, developmental toxicity
43%, 28%
What does IRIS stand for?
Integrated Risk Information System
% of DALYS attributed to the environment for children (0-14) vs overall
36% children to 24% overall
**Major issue in developed countries:
chronic diseases (e.g. asthma, developmental disorders, childhood leukemia, brain cancer
It is hypothesized that how much of childhood disease is due to environmental influence?
the majority
Estimated cost due to lead poisoning, asthma, cancer, and neurobehavioral disorders: (dollars and percentage of total annual illness cost)
$54.9 billion dollars
2.8% of total annual illness cost
**Primary issue in developing countries, and why:
poverty
due to environmental injustice, more risky behaviors (e.g. smoking, diet), poor access to services
**Major threats in developing countries (5):
- perinatal diseases
- respiratory diseases
- diarrheal diseases
- insect-borne diseases
- physical injuries
Why time in DALYs is so large for children?
The issues happen so much earlier in life.
**Health problems associated with lead poisoning in kids (6):
- decreased bone and muscle growth
- poor muscle coordination
- damage to the nervous system, kidneys, and/or hearing
- speech and language problems
- developmental delay
- seizures and unconsciousness (in extreme cases)
Lead is what type of toxicant?
Neurotoxicant
**Observed effects of pesticides on children?
- multiple organ effects (incl. CNS, lungs, kidneys, digestive, immune)
- cancer (incl. brain, non-Hodgkin’s lymphoma, leukemia)
- from in utero exposure: limb reduction, undescended testes, neural tube defects, heart problems, impaired fetal growth
Are children little adults?
No; they’re particularly susceptible to environmental contaminants
Reasons that children are more highly exposed (relative to adults and adjusted for body weight):
- drink more water
- eat more food
- diets include oft-contaminated fruit juices
- breathe more air
- hygiene/hand-to-mouth behaviors
What pathways in children are underdeveloped?
Metabolic detoxification pathways
What systems are particularly vulnerable due to the rapid growth and development of children?
nervous, immune, reproductive, endocrine, cardiovascular
NRC Report Recommendations (4):
- Better data on children’s exposure to pesticides
- need toxicological studies to examine the long-term and delayed effects of early exposure to pesticides
- examine pesticide interactive effects
- set standards providing extra margin of safety for children
First regulation to protect children’s health against environmental hazards
Food Quality Protection Act of 1996
Food Quality Protection Act of 1996 did what?
- health-based standards oriented toward children and infants
- extra margin of safety to protect children
- requires consideration of interactive and endocrine effects
Executive Order on Children’s Environmental Health and Safety of 1997?
- recognizes children’s environmental health as a priority
2. established cabinet-level committee on children’s environmental health (EPA and DHHS co-chairs)
Study with the goal of systematically examining the impact on children’s health and development from early exposure to environmental toxicants
The National Children’s Study
the most serious consequence of pediatric lead poisoning
brain injury
why children are particularly vulnerable to lead
rapidly developing brains, normal hand-to-mouth behavior increases the risk that they will take lead from the environment into their bodies
There are certain periods during a child’s life when they are more susceptible to certain environmental pollutants than at other times, true or false?
True
Four main exposure factors for children:
- contact rates (more food/water, hygiene, high dermal surface area to volume ratio, ventilation rate)
- contact with contaminated environmental media (hygiene, oral exploratory behavior, soil/dust/carpet, diet contains food likely to be contaminated)
- time activity patterns (time indoors/outdoors)
- location (schools, daycare, grandparents, playground… breathing zone closer to floor)
Three concerns:
- developmental vulnerability
- biological components
- exposure components
ADMT:
absorption, distribution, metabolism, target organ specificity
two exposure circumstances unique to children:
trans-placental transfer, breast milk ingestion
Ways to reduce exposure in children:
buying organic fruits and vegetables, rinsing food, peeling, diverse diet
PBDEs:
Polybrominated Diphenyl Ethers
may have hormone disruption effects/be neurodevelopmental toxicant, banned in Europe in 90s and CA in 2006
Aftermath of the mis-represented CHEERS study:
- researchers should seek community consultation and participation in studies
- studies should not have unfair representation of the poor or under-represented populations
- avoid controversial financial conflicts of interest
- make clear “observational” nature of study (in contrast to intentional dosing)
Ethical concerns of research conducted with children:
children are vulnerable and unable to provide informed consent
