Background Information
Fluorine (F)
Fluorine is an abudant naturally occuring element. It is present
in combination with other elements and is commonly called fluoride.
Sulfuryl fluoride
- Sulfuryl fluoride - "insecticide used to fumigate closed
structures and their contents such as domestic dwellings, garages,
barns, storage building, commercial warehouses, ships in ports,
and railroad cars. It controls numerous insects pests including
termites, powder post beetles, old house borers, bedbugs, carpet
beetles, cloths moths and cockroaches, as well as rats and mice."
(US
EPA, 1993)
- Toxicity - animal studies show - flurosis of the teeth, decreased
body weights, effect on lung, nervous system and brain. Human
risk neurotoxicity - exposure limit 2 ppm air inhalation. (US
EPA, 1993)
Hydrogen fluoride
- "Hydrogen fluoride is used in the production of aluminum
and chlorofluorocarbons, and in the glass etching and chemical
industries. Acute (short-term) inhalation exposure to gaseous
hydrogen fluoride can cause severe respiratory damage in humans,
including severe irritation and pulmonary edema. Severe ocular
irritation and dermal burns may occur following eye or skin exposure
in humans." (U.S.
EPA 1992)
Fluoride in drinking water
- "Chronic (long-term) exposure of humans to fluoride at
low levels has a beneficial effect of dental cavity prevention
and may also be useful for the treatment of osteoporosis. Exposure
to higher levels of fluoride through drinking water may cause
dental fluorosis or mottling, while very high exposures through
drinking water or air can result in skeletal fluorosis in humans.
The only developmental effect observed from fluoride exposure
in humans is dental fluorosis which can occur in a child's teeth
when a mother receives high levels of fluoride during pregnancy.
EPA has not classified hydrogen fluoride for carcinogenicity."
(U.S.
EPA 1992)
- Summary for Fluoride - CalEPA
- Office of Environmental Health Hazard Assessment
"A Public Health Goal (PHG) of 1 ppm (1,000 ppb) is developed
for fluoride in drinking water. This level is intended to be
an approximate year-round average. The U.S. Environmental Protection
Agency’s (U.S. EPA’s) Maximum Contaminant Level
(MCL) for fluoride is 4 mg/L. U.S. EPA’s MCL was set to
protect against crippling skeletal fluorosis, with a secondary
MCL of 2 mg/L to protect against dental fluorosis (in mild cases,
fluorosis is a slight discoloration of teeth, in more severe
cases it can lead to pitting and breaking of the teeth). Moderate
to severe dental fluorosis is rare when the drinking water fluoride
level is in the range of 1 mg/L, but begins to become significant
at concentrations close to 2 mg/L. The PHG is based on a no-observed-adverse-effect-level
(NOAEL) of 1 mg/L for dental fluorosis in children. A relative
source contribution of 100% (1) was applied yielding a calculated
PHG of 1 mg/L. This level is judged to be the optimum
level for reducing the prevalence of dental fluorosis while
providing protection against dental caries. In reviewing
the available data on health effects of fluoride, studies have
been found which provide some indication that there may be a
causative relationship between lifetime consumption of fluoridated
drinking water and increased incidence of hip fracture in the
elderly. However, this health endpoint is not sufficiently established
at present to provide the basis for calculating a PHG. Therefore,
OEHHA calculates a PHG of 1 mg/L (1 ppm) for fluoride in drinking
water."
- Chronic Reference Exposure Levels (RELs) for fluorides 0.04
(mg/kg-day) - hazard Bone and teeth (CalEPA)
- National
Academy of Science - Toxicologic Risk of Fluoride in Drinking
Water - Study under way by National Academy of Science Project
Scope:
A subcommittee of the National Research Council's (NRC) Committee
on Toxicology (COT) will review toxicological, epidemiological,
and clinical data, particularly data published since 1993, and
exposure data on orally ingested fluoride from drinking water
and other sources (e.g., food, toothpaste, dental rinses). Based
on those reviews the subcommittee will evaluate independently
the scientific basis of the U.S. Environmental Agency's (EPA)
maximum contaminant level goal (MCLG) of 4 milligram per liter
(mg/L) and secondary maximum contaminant level (SMCL) of 2 mg/L
in drinking water. The subcommittee will advise EPA on the adequacy
of its fluoride MCLG and SMCL to protect children and others from
adverse effects. The subcommittee will consider the relative contribution
of various fluoride sources (e.g., food, dental-hygiene products)
to total exposure. The subcommittee will also identify data gaps
and make recommendations for future research relevant to setting
the MCLG and SMCL for fluoride. The subcommittee will not address
questions of economics, risk-benefit assessment, or water-treatment
technology.
Summary of health effects
Health Effects of Fluoride
Fluoride is readily absorbed and similar to lead incorporates
into bone. The most well documented health effect of low-level
exposure to fluoride is dental fluorosis. Dental fluorosis is
a visible defect in the tooth enamel that is caused by damage
to the tooth forming cells during childhood. Chronic exposure
to excessive levels of fluoride can lead to skeletal fluorosis,
a weakening of the bones with symptoms similar to arthritis.
Fluoride is widely used as an insecticide and rodenticide. Common
rodentcides include sodium fluoroacetate and fluoroacetamide.
These compounds are common used in rodent bait and readily kill
mice or rats by interfering with metabolic processes (lethal dose
approximately 0.2 mg/kg). Human ingestion results in nausea, cardiovascular
effects, hypotension, renal failure, CNS symptoms of agitation,
seizures, coma and death.
More recent studies of the effects of fluoride indicated a range
of effects on a number of organs. There is indication from animal
studies that fluoride accumulates in the pineal gland and effect
the synthesis of melatonin. There are also studies indicating
that fluoride adversely effects the developing nervous system.
It is not possible to provide a full review of the developmental
or adults health effects of fluoride. Extensive information is
available on the Fluoride Action Network website .
REFERENCES
/ ADDITIONAL INFORMATION
European, Asian, and International Agencies
North American Agencies
Non-Government Organizations
References
- The Fluoride Deception by Christopher Bryson, Theo Colborn.
Seven Stories Press (February 1, 2004) . 272 pages.
- Dietary Reference Intakes for Calcium, Phosphorus, Magnesium,
Vitamin D, and Fluoride (1997). Standing Committee on the Scientific
Evaluation of Dietary Reference Intakes Food and Nutrition Board.
Institute of Medicine. NATIONAL
ACADEMY PRESS Washington, D.C. (http://books.nap.edu/catalog/5776.html)
- Erdal, S. and Buchanan, S.N. A Quantitative Look at Fluorosis,
Fluoride Exposure, and Intake in Children Using a Health Risk
Assessment Approach. Environ Health Perspect 113:111-117 (2005).
(on
line EHP). (accessed 13 May 2005).
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