Having clean drinking water is an important part of survival for humans and animals alike. In addition to the benefits of drinking clean water, water that is enriched with additives may provide a source of necessary substances for humans that they may not receive elsewhere.
How does fluoride help dental health?
One such common substance added to public drinking water is fluoride. Fluoridation of water is done to prevent tooth decay by increasing an individual’s fluoride intake. Fluoride is known to be effective at strengthening tooth enamel and preventing subsequent decay and is often added to the water supplies of areas with little access to dental care. Although water fluoridation is safe and effective at preventing tooth decay in humans, it may pose threats for animals that have lower fluoride toxicity levels than humans.
How much fluoride is added to the water supply?
For humans, water fluoridation is inexpensive and good for public health. The cost of fluoridating water is approximately $0.95 per person per year, which is considerably less than the cost of having a cavity filled at a dentist. The recommended fluoride level for drinking water is approximately 1.0 milligrams per litre, and public water supplies with naturally occurring levels of fluoride below 0.7 milligrams per litre are commonly enriched. At this dosage, the benefits of tooth protection far outweigh any risk of toxicity. Negative effects from exposure to fluoride are generally only seen in doses exceeding 20 milligrams per litre, in which phosphate enzymes may be inhibited. An excess of 70 milligrams per litre will lead to heart burn, pain in the extremities and in some cases staining of the teeth, which can only be corrected by a cosmetic dentist.
What are the negative side effects of fluoride?
Although these levels of fluoride in public drinking water are safe for humans, they may be toxic for other organisms. Toxicity levels are very low for bacteria used in waste-water treatment. If these bacteria are not present, the concentration of fluoride excreted by humans into waste water will increase. Exposure to higher levels of fluoride poses a threat for aquatic life and animals that have low sensitivities to fluoride. Many freshwater fish cannot thrive in water with fluoride levels higher than 7.5 milligram per litre. There is also the issue of bio-magnification, in which animals higher on the food chain receive more fluoride by consuming other animals that have been exposed to fluoride. This can be especially harmful for birds that consume fish; birds may experience reduced growth rates with doses as low as 13 milligrams per litre.
What is your opinion?
When considering the overall safety of water fluoridation, it is important to observe the effects on animals and the environment to make a proper and well-informed analysis and the heated debate over fluoridated water continues to this day.