A recent article in the Neiro Toxicology Journal reports evidence that public drinking water treated with sodium silicofluoride or fluosilic acid, known as silicofluorides (SIFs), is linked to higher uptake of lead in children. Sodium fluoride, first added to public drinking water in 1945, now is used in less than 10 percent of fluoridation systems nationwide. Instead SIFs are used to treat drinking water delivered to 140 million people. While sodium fluoride was tested on animals and approved for human consumption, the same cannot be said for SIFs. Researchers found that the greatest likelihood of children having elevated blood lead levels occurs when they are exposed both to known risk factors, such as old house paint and lead in soil or water, and to SIF-treated water.