NaF was often used as a roach powder and rat poison and against chicken and animal lice. All of these salts were sufficiently soluble and absorbable to cause mottling of teeth in white rats. The fluoride ion also delayed calcification of leg bones in young rats. Fluorides can concentrate in plants and accumulate in soils, especially through the application of untreated phosphate rock. The use of fluorine compounds as insecticides is growing, and in years to come the quantity of fluorine added to soils through this source may be considerable.
Fluoride collects in the aorta, skin, skeleton, and cataracts.
Fluoride inhibits many metabolic enzymes. Because it interferes with the liver's detoxifying enzymes, it is probably enhancing the effects of other toxic substances in synergistic fashion. The more fluoride we add to the environment, the more toxic other substances may become. Baby foods and juices should contain no more than 0.01 ppm fluoride. Exposure to fluoride through food, air and water has been increasing for 50 years from many uncontrolled industrial sources and conventional agricultural practices as well as the use of some dental products and medicines.