Although the first public drinking water supply in this country was fluoridated 56 years ago, the impact of fluoride on the environment has only recently begun to be studied.
Unlike health impacts, which have been the subject of hundreds of research articles by university scientists published in academic journals worldwide, the buildup of fluoride in water supplies and in plants and animals has received short shrift.
But in recent years, researchers have begun to explore links between fluoride buildup and environmental problems as diverse as delayed salmon migration, ponderosa pine needle discoloration and lead ingestion by children. Most of their findings have not been published in peer-reviewed journals, but they are beginning to raise questions about the need for broader studies.
In Flagstaff, fluoride in drinking water would be introduced into the environment largely from the city wastewater treatment plants, which discharge 1.7 billion gallons of wastewater into the Rio de Flag each year. An additional 537 million gallons of recycled water provided by the city to irrigate golf courses and public parks would also bring fluoride into regional ecosystems.
The Environmental Protection Agency’s standard for fluoride concentrations in drinking water is a maximum of 4 parts per million, but Flagstaff intends to keep its level at 1 ppm.
Surface runoff from sprinklers, car-washing, fire-fighting and watering lawns would also bring fluoride into the Flagstaff environment.
Ponderosa pine is an “indicator” plant vulnerable to fluorides in the environment, according to a study of the effects of fluorides on plants, say researchers Alan Davison, an agriculture and environmental scientist at the University of Newcastle upon Tyne, U.K, and Leonard Weinstein, an environmental biologist at Cornell University.
Coniferous forests such as ponderosa pine can be damaged by accumulations of fluoride at one part per billion or less, some researchers say.
Plants absorb fluoride as a gas when it evaporates from standing water or when it’s sprayed into the air, say from sprinklers at a golf course or home using fluoridated water or recycled supplies.
“… young ponderosa pine needles first exhibit a lightening in color which turns light brown to reddish-brown at the tips and progresses … along the needle. The discoloration is often accompanied by narrow, dark banded zones, which may be the result of intermittent exposures to fluoride spaced at different periods,” wrote Davison and Weinstein in Earth Island Journal.
Fluoride exposure kills pine needles, flecks leaves on corn and causes bark on fruit trees to turn mottled and kills their sensitive leaves, the researchers found.
They noted that because a ponderosa pine or fruit tree is visibly injured by fluoride, it is not necessarily dying and that “there have been some cases of spectacular recovery of trees after severe injury.”
“Conversely, just because a plant does not show visible injury does not mean that there is no effect of fluoride assimilation or growth. Predicting the effects of fluoride is not a job to be undertaken lightly,” Davison and Weinstein wrote.
INDUSTRIAL POLLUTANT
Fluoride contamination, from industry and public water supplies, has concerned some government agencies and scientists for the past 25 years, reports Gar Smith, editor of Earth Island Journal, a San Francisco-based environmental journal.
Smith said that the effects of fluoride on plants and animals is being slowly documented in various national and international studies ranging from the National Research Council to Environment magazine and the National Park Service.
Some researchers have warned that fluoride contained in water released by wastewater treatment plants appears to concentrate in water bodies at levels higher than recommended levels.
“Because fluoride does not break down, it slowly accumulates in the environment,” Smith wrote in a Journal special report.
Airborne fluoride has long been a problem in areas near aluminum smelters and other industrial sources of the chemical. The National Research Council warned in 1971 that fluoride pollution from U.S. industry had caused damage to plants and posed a serious risk to livestock grazing on grasses exposed to concentrations of fluoride less than 1 part per billion. The Council found that livestock some 20 miles from a fluoride-emitting aluminum smelter had accumulated levels of fluoride that were “200,000 times” more than those found in ambient air samples.
A U.S. Department of Agriculture handbook quoted in Earth Island Journal said “airborne fluorides have caused more worldwide damage to livestock than any other air pollutant.” The symptoms of fluoride damage in animals and humans include dental mottling, respiratory distress, stiffness in knees and joints, anemia, weakness and nausea.
SALMON AT RISK?
In addition to industry, the accumulation and migration of drinking water fluoride currently is being suspected as a cause for the decline of the salmon fishery in the Northwest U.S. and British Columbia by researchers Richard G. Foulkes and Anne Anderson in Earth Island Journal. The pair sifted through 21 articles and studies conducted on the issue by U.S. and Canadian water quality and fisheries scientists.
The salmon’s “critical habitat” has been found to have measurable levels of fluoride flowing from fluoridated communities and aluminum industry smelters. The researchers said the presence of fluoride maycause salmon to delay migration as they avoid the chemical that contributes to increased mortality and reduced chances to spawn successfully.
One peer-reviewed study of salmon migratory habits that were found to be disrupted by fluorides was conducted from 1982 to 1986 by researchers Douglas Dey and DM Damaker and published by the National Oceanic and Atmospheric Administration. The researchers found that after fluorides discharged by an aluminum plant were greatly reduced, salmon migratory delays and mortality decreased to “acceptable levels”.
FLUORIDE AND LEAD?
Dartmouth College research professor Roger Masters is president of the Foundation for Neuroscience and Society, and he has studied the possible link between fluoride ingestion and increased lead in children. He is worried that most health studies of fluoride have focused on a fluoride compound used only in a minority of drinking water supplies.
Research shows that 91 percent of the fluoridated water in America is treated with hydrofluosilcic acid or sodium silicofluoride. The remaining communities use a pure pharmaceutical grade called sodium fluoride, the same ingredient used in tooth paste and other dental hygiene products.
While sodium fluoride has been tested extensively for both its purity and impact on public health by researchers and fluoride industry groups, commercial grades of fluoride-bearing chemicals “have not been properly tested for health and behavioral effects,” he said.
Added Masters: “If you feel a bit funny, it makes a big difference if you take an aspirin or cocaine.”
Masters asked the EPA directly for all its studies on fluoride-bearing chemicals such hydrofluosilcic acid and their effects on health and behavioral effects.
Two letters dated June 23, 1999 and Nov. 16, 2000 from the EPA responding to inquiries from Masters and the U.S. House Subcommittee on Energy and the Environment conclude that no “empirical scientific data” on the “health effects” of hydrofluosilcic acid is in the EPA’s possession.
Pure sodium fluoride, used in about 10 percent of community fluoridation systems, “disassociates” or breaks down into molecules easily. Safety and purity tests are conducted on sodium fluoride have been used to justify the safety of hydrofluosilcic acid and other grades of commercial fluoride added to public drinking supplies, Masters said.
This lack of scientific study on a chemical introduced into the drinking water of an estimated 100 million Americans upsets Masters. His data, published recently in neuroscience and toxicity science journals, said silicofluorides are “associated with lead toxicity, including learning disabilities and higher rates of crime.”
Masters said his data “strongly suggests that silicofluorides enhance the human body’s uptake of lead from environmental sources.” Lead is prevalent in the atmosphere from gasoline additives.
Kneka Hayward, chief of the Arizona Office of Oral Health, insists there is no connection at all between fluoridation and the maladies and social consequences outlined by Masters’ research at Dartmouth College. But she said she was not familiar with Masters’ work and did not offer any evidence to reject his claim other than a blanket statement that fluoridation has not been linked to such mental health problems.
Clean water advocates in states, such as New Hampshire, are trying to pass laws requiring that all chemicals, especially fluoride, that are put in drinking water be tested to ensure that they don’t contain harmful contaminants like heavy metals.
Masters recently testified in favor of a proposed New Hampshire law requiring the testing of chemicals. The bill is opposed by state Department of Environmental Services as setting “vague and unattainable standards.”
ARSENIC IN FLUORIDE COMPOUND
Testing of hydrofluosilicic acid, which city of Flagstaff officials indicated would be used if fluoridation is approved here, has found minute quantities of heavy metal contaminants, such as lead, mercury and arsenic, according to the National Sanitation Foundation, the chemical industry watchdog group monitoring fluoride.
The NSF, in a report made to Congress July 7, 2000, said that when detected, the “average” level of arsenic contamination found in the acid would create arsenic levels of about 0.43 parts per billion when diluted. The maximum amounts of arsenic detected by NSF chemists would result in arsenic levels approaching 1.66 parts per billion.
The EPA is changing its current acceptable level of arsenic contamination in drinking water from 50 parts per billion to 10 parts per billion in June. One part per billion is roughly the equivalent of having a pound of material in 120 million gallons of water.
Flagstaff officials expect to spend up to $300,000 for filtration equipment to remove current levels of arsenic to comply with the new EPA standards.
The National Resources Defense Council says that even the new EPA standards are not adequate to protect public health.
The environmental group cites a National Academy of Sciences warning that a 3 parts per billion arsenic exposure “could pose a fatal cancer risk several times higher than EPA has traditionally accepted in drinking water.”
National Academy of Science studies have found that drinking water with just 0.5 parts per billion levels of arsenic presents a 1 in 10,000 risk of developing cancer of the liver, prostate, bladder, lungs, skin and kidneys.