Fluoride poisoning: a puzzle with hidden pieces.

Key industry data regarding harm from chronically inhaled fluoride have been unavailable publicly for decades. Recent unveiling of unpublished reports reveals three examples of data mishandling that disguised the need for more stringent occupational standards for particulate and gaseous fluorides and fluorine. Injury reports from workers handling chemicals show that unjustifiable reductions of injury and disability numbers in the process of publication shifted concern from respiratory to mineralized tissue damage. Selective editing and data omissions allowed bias that fluoride reduces caries without detrimental effects. Finally, industry's failure to publish an important industry-funded laboratory study buried knowledge of low thresholds for fluoride-induced lung disease. Data from that study are presented to clarify the dose- and duration-dependent changes caused by chronic inhalation of calcium fluoride.