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YOUR CHILD'S VULNERABILITY TO TOXIC SUBSTANCES IN
THE ENVIRONMENT
George Glasser / Andreas
Schuld
Children's Environmental
Health Network: "The US has seen a worrisome increase in certain childhood
diseases, and researchers are working hard to determine whether this
increase is linked to environmental exposures. As noted, childhood asthma
has increased by more than 40% since 1980, affecting more than 4.2 million
children under the age of 18 nationwide. The incidence of two types of
childhood cancers has risen significantly over the past 15 years: acute
lymphocytic leukemia is up 10% and brain tumors are up more than 30%.
Although there are no registries for learning disabilities and attention
deficit disorders among children, there has been growing attention in recent
years to an apparent increase in both.
"In 1997, President Clinton
issued an Executive Order addressing protection of children from
environmental health risks. The Food Quality Protection Act of 1996 and the
Safe Drinking Water Act of 1996 both require consideration of infants and
children in risk assessments used to determine acceptable levels of
environmental contaminants in food and drinking water. In 1996,
Administrator Browner issued a report entitled Environmental Health Threats
to Children and set a Children's Agenda for EPA, calling for consideration
of children's risks in all Agency actions and a greater emphasis on research
to support children's risk assessments." (Children's Vulnerability To Toxic
Substances In The Environment Science to Achieve Results Program: 1999
Research Grants National Center for Environmental Research and Quality
Assurance/USEPA.)
Some progressive
researchers are calling for recognition of children's risks from exposure to
environmental contaminants. However, not many researchers and toxicologists
want to admit that they still predicate their research on 14th century
dogma: "The dose alone makes the poison." To these researchers, children are
merely small adults; however, a child's system is very different to that of
an adult. A child's system is continually developing. The ratio of child
intake rate to child body size is greater than that for adults for some
routes, including the skin.
EPA states:
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Physiological differences influence the
amount of chemical that is absorbed into the body. Children have a greater
surface area to body weight ratio than adults, which may lead to increased
dermal absorption. Comparisons of absorption through the respiratory and
gastrointestinal tract between children and adults are complex and could
lead to either increased or decreased risk depending on the
physicochemical properties of the toxic chemical.
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There are several interconnected factors
that may contribute to increased vulnerability for children, depending on
the toxic substance under consideration and the age of the child.
Children's tissues, organs and biological systems are still developing,
with several stages of rapid growth and development occurring from infancy
to adolescence. This rapid development and immaturity of body organs and
systems predisposes children to potentially more severe consequences
within certain age ranges and windows of vulnerability. Another factor
that can influence a child's vulnerability is that circulator flow rates
are generally higher in children, which may increase a child's
susceptibility to toxic effects. A child is not an adult, but most
toxicological data are based on occupational exposures for adults.
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A main route of exposure to toxicants in
municipal water for children is the skin. Studies done by H.S. Brown,
Ph.D., D.R. Bishop, MPH, and C.A. Rowan, MSPH in the early 1980s showed
that an average of 64% of the total dose of waterborne contaminants is
absorbed through the skin.
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Also, studies by Dr. Julian Andelman,
Professor of Water hemistry, University of Pittsburgh Graduate School of
Public Health, found less chemical exposure from drinking contariiinated
water than using it to wash the clothes or take a shower (American Journal
of Public Health, May 1984).
Parents interviewed about
their children's bath times state that their young children may stay in a
bath from forty?five minutes to two hours. The exposure to waterborne
contaminants in tap water can range from chlorides to a multitude of
chemicals depending on the water source and chemicals added to the water at
the treatment plant. While most of the adverse effects from the chemicals
are well documented, i.e., occupational exposures and/or oral exposures
geared to adults, however, children's dermal, inhalation or oral exposures
are not considered.
Even when dermal exposures
are taken into account, the fact that sodium lauryl sulfate (SLS) found in
most shampoos, soaps and bubble baths is not. Drug companies use SLS in
medicines to enhance the absorption of medicines internally and through the
skin [5].
An experiment done with
sodium fluoride and SLS showed that SLS increased the absorption of fluoride
in the mouth by nine per cent. However, no experiments have been done to
determine the effect of SLS on absorption of contaminants from tap water.
Researchers say that
ingestion, inhalation and dermal absorption are similar, and all routes must
be used to calculate the total risk when making policy decisions regarding
the quality of the municipal water. However, with the exception of chlorine,
these dermal and inhalation exposure factors are not taken into account with
other water treatment chemicals.
EPA established the maximum
contaminant levels for fluorides in the drinking water based on oral
ingestion of treated tap water. Interestingly, the US Public Health Service
established the optimal level for fluorides in the drinking water without
ever having considered dermal or inhalation exposures or the potential of
enhanced dermal absorption triggered by SLS in soaps.
Surprisingly, ingestion
is not the most efficient way to deliver toxicants into the system.
Depending on whether a
child has eaten or if there is residual food in the stomach, about 20?50% of
the contaminants are absorbed directly into the blood stream. Of the three
modes of exposure, dermal exposures are the most efficient: virtually 100%
of the contaminants are absorbed into the system.
One EPA scientist said,
"For instance, a shower cubicle can be considered an 'exposure chamber'.
Exposure to volatile contaminants absorbed via the lung would be about
double the same amount from drinking water. In the bath, underarms (axilla),
scrotal and vaginal areas as well as the groin absorb far greater amounts
than in the normal un-washed forearm test."
With the recommendations
for daily intake of fluorides for children the most significant route of
exposure was ignored: dermal exposure.
Researchers on both sides
of the drinking water fluoridation issue have failed to account for
inhalation and dermal exposures to fluorides.
Possibly the most troubling
aspect is that the most popular fluoridation agent is fluorosilicic acid
derived from phosphate fertiliser production. While the US Public Health
Service and American Dental Association say the addition of the pollution
scrubber liquor is the most significant health measure of our time, the
USEPA office of Air and Radiation states, unequivocally about the same
product:
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"1996, USEPA Office of
Air and Radiation, 40 CFR Part 63 [IL-64-2-5807; FRL-5656-4] RIN 2060-AE40
and 2060-AE44: SUMMARY: hazardous air pollutants (HAPs) emitted by the
facilities covered by this proposed rule include hydrogen fluoride (HF);
arsenic, beryllium, cadmium, chromium, manganese, mercury, and nickel (HAP
metals); and methyl isobutyl ketone (MIBK) emissions. Human exposure to
the HAP constituents in these emissions may be associated with adverse
carcinogenic, respiratory, nervous system, dermal, developmental and/or
reproductive health effects."
On 10 May 1999, US Rep. Ken
Calvert, US House Subcommittee on Energy and the Environment, wrote to the
US Environmental Protection Agency. The response, dated 23. June 1999, was
made by J. Charles Fox, USEPA Assistant Administrator, at EPA Headquarters.
In answer to Question Two: "What chronic toxicity test data are there on
sodium fluorosilicate? On hydrofluorosilicic acid...?" Fox wrote: "In
collecting the data for the fact sheet EPA was not able to identify chronic
studies for these chemicals."
Aside from the much debated
fluoride issue, there is a component of the product that might be as
bioactive as fluorine. It does not appear on Material Safety Data Sheets (MSDS)
or in any quality control specification sheets (contaminant analyses).
However, the component is part and parcel of the empirical formula and the
chemical name, Silicon/Silica. All US government agencies are aware of this
inherent, possibly carcinogenic, component of fluorosilicates, but refuse to
acknowledge it: Silica.
The molecular silica is
also absorbed through the skin. Recent studies strongly suggest that
exposure to silicates may be a factor in the development of primary brain
tumors and Alzheimer's disease (Alzheimer's like dementia). [1,2,3,4]
The levels of silica in the
fluorosilicates exceeds the US Federal Hazardous Communication Standard for
warning labels, certifying laboratories or the manufacturers do not report
the silica levels. Even after the levels of silica were verified and
reported to the US OSHA, the occupational safety agency never took action.
The health threat from
using fluorosilicates to fluoridate drinking water goes beyond bathing and
drinking the treated water. The substances in the fluorosilicates do not
magically vanish as USEPA would have people believe. All the captured
pollution is retained in the average home from washing clothes and household
items, evaporation from clothes dryers and dishwashers, and using the water
for general household cleaning chores. In essence, water fluoridated with
the pollution scrubber liquor from phosphate fertiliser production is a
vehicle to carry all the hazardous air pollutants directly into your home.
For young children,
secondary contamination from the fluoridated water is significant and has
never been investigated by USPEA or the US Public Health Service although
both agencies are aware that pollution scrubber liquor is being used to
fluoridate municipal water supplies. In fact, the EPA acknowledges potential
household risks for exposure from water contaminated with low levels of
pesticides and other contaminants:
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Children's daily
activities, proximity to floors, carpets, lawns and soils, the frequency
and duration of hand to mouth behaviours, and many other factors combine
to form a life environment that varies with age and from child to child.
Studies suggest, for example, that children's normal activities may expose
them to higher levels of pesticides applied in and around the home.
Children also have greater average daily food consumption per unit body
weight than do adults, and children differ in the specific foods eaten and
in the relative proportions of various foods.
In exploring the factors
that affect health risk from exposure to toxic chemicals, it must be
remembered that children are a unique sub-population. Depending on the
circumstances, children may be more or less susceptible to the toxic effects
of these chemicals than are adults. Risks to children may differ
qualitatively or quantitatively from those to adults because of differences
in their immature physiology, metabolic processes, respiratory rates and
differing levels of exposure. Nutritional status, disease and genetic
variation can affect many of these processes, increasing or decreasing the
risk from exposure to toxic substances.
The Organization Physicians
for Social Responsibility states:
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Our children are
especially at risk. Their growing bodies are more vulnerable to harm from
hazards in the environment. Small amounts of air or water pollution that
may have little or no impact on a healthy adult, can make children,
especially newborns, seriously ill. Children's longer lives also make them
more vulnerable to slow-acting hazards, like pesticides and dioxins.
World Health Organization:
Inhalation and dermal absorption/Water contaminants
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The contribution of
drinking water to daily exposure includes direct ingestion as well as some
indirect routes, such as inhalation of volatile substances and dermal
contact during bathing or showering. In most cases, the data were
insufficient to permit reliable estimates of exposure by inhalation and
dermal absorption of contaminants present in drinking water. It was not
possible, therefore, to address intake from these routes specifically in
the derivation of the guideline values. However, that portion of the total
tolerable daily intake (TDI) allocated to drinking water is generally
sufficient to allow for these additional routes of intake (see section
4.1). When there is concern that potential inhalation of volatile
compounds and dermal exposure from various indoor water uses (such as
showering) are not adequately addressed, authorities could adjust the
guideline value.
The lack of information
regarding the absorption by skin is particularly disturbing as recent
research has uncovered hundreds of papers in the European literature
regarding the use of fluorides as effective anti-thyroid medication,
including bath therapy. Between 1932 and 1962 Gorlitzer von Mundy cured over
650 patients suffering from hyperthyroidism (over-functioning thyroid gland)
effectively with baths containing hydrogen fluoride (HF).
After first conducting over
1500 trials on mice and tadpoles, he prescribed 20-minute full baths
containing 30 ccm of concentrated HF per 200 litres of water. Temperature
was mostly 36° Celsius. It took on average 15 baths to completely cure the
patients, who also gained 20 kg of weight as a result. He warned that such
treatment should only be applied to hyperthyroid patients, for to apply such
measures to euthyroid (normal) people would surely lead to hypothyroidism.
Although the reality of
children's vulnerability to exposures to environmental toxicants has been
acknowledged, little is happening. Children don't vote and the parents are
kept ignorant by the government, scientists and the media. It seems that
only a few voices express concern, but those voices are virtually smothered
by the sound of money changing hands.
References:
1. Forbes WF; Agwani N, J, A suggested
mechanism for aluminum biotoxicity; Theor Biol; VOL 171, ISS 2, 1994,
P207?14.
2. Cerebrospinal fluid trace element content
in dementia: clinical radiologic, and pathologic correlations; Hershey CO,
Hershey LA, Varnes A, Vibhakar SD, Lavin P, Strain WH; Neurology 1983 Oct;
33(10); 1350?3
3. Jacqmin?Gadda H, Commenges D, Letenneur L,
Dartigues JF, Silica and aluminum in drinking water and cognitive impairment
in the elderly; Institut National de la Sante et de la Recherche Medicale
U330, Bordeaux, France. Epidemiology 1996 May; 7(3):281?5.
4. Hadfield MG, Adera T, Smith B,
Fortner?Burton CA, Gibb RD, Mumaw V; Human brain tumors and exposure to
metal and non?metal elements: case?control study; J Environ Pathol Toxicol
Oncol 1998; 17(1):1?9; Department of Pathology, Medical College of
VirginiaNirginia Commonwealth University, Richmond 23298, USA.
5. journal of Dental Research 1990, Vol. 69,
pg 827, Abstracts of Posters; (8) Plasma F Levels Following Intake of NaF in
Combination with Sodium Lauryl Sulphate. P. Barkvoll (University of Oslo,
Norway).
Sodium lauryl sulphate (SLS) is one of the
most widely used detergents in toothpastes, and it is known that it
increases the permeability of rat oral muscosa. The aim of the present study
was to investigate the plasma F- concentrations in humans after intake of
NaF with and without addition of SLS. In the first experiment, five subjects
received an aqueous solution of 3 mg F- as NaF in a 30-ml solution
immediately followed by intake of 30 ml of distilled water. In the second
experiment, the subjects received an aqueous solution of 3 mg F- as
described above, followed by an aqueous solution of 30 mg SLS dissolved in
30 ml of distilled water. All the solutions were freshly prepared. Capillary
blood samples were collected and the relative fluoride concentration in
plasma determined. Sampling was performed before and 0.25, 0.5, 0.75, 1,
1.5, 2, 3, 5 and 6.5 hours after the administration. All the subjects had a
higher relative fluoride concentration in blood plasma after intake of
fluoride in combination with SLS than of fluoride alone (p<0.05). The mean
increase was nearly 9%. This effect by SLS may be a point to be considered
when absorption of fluoride from swallowed toothpaste is evaluated.
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