Pennsylvania American Water Company (PAWC) recently notified the Division of Operations Monitoring and Training, as well as all DEP regional offices about a potential fluoride shortage.  PAWC's supplier notified the water company that they will be severely limiting deliveries of Fluorosilicic Acid over the next few months.  The supplier stated that causes for the market balance are as follows:

• The U.S. has noted unusually hot and dry conditions during the spring and summer causing increased demand.

• Producers are close to anticipated volumes; however production has been inconsistent and less than last year at this point.

• Production issues during the last half of 2006 depleted inventories, resulting in current order patterns that suggest users are attempting to replenish their inventories to the two-three month levels that they normally attempt to maintain.

• Some phosphate plants are closed or have been idle during the last 14 months due to industry consolidation, reducing the Fluorosilicic Acid supply at the source.  Producers are evaluating additional capacity at their existing plants.

The Centers for Disease Control (CDC) has added a page to their web site specifically addressing the temporary shortage of Fluoride.  The Web site is: http://www.cdc.gov/fluoridation/fact_sheets/shortages_faq.htm

This presents a potential problem for water suppliers that have a permit to fluoridate and must meet permit conditions stipulating optimum fluoride levels that must be maintained in their distribution systems – generally 0.7 – 1.2 mg/L.  The question arose as to whether water systems that fluoridate should cut back their levels to sub-optimum levels to conserve chemical, or continue to fluoridate at permit-required levels and hope that they will be able to replenish their inventories before they run out.  

PA DEP’s position is that these water suppliers should continue to fluoridate at the required permit levels for two reasons:

• If water suppliers reduce the level, they could be voluntarily and perhaps unnecessarily putting themselves in violation of a permit condition, and the possibility exists that they might not run out of fluoride anyway.

• Based on available literature, including a CDC table that displays recommended levels based on average daily maximum air temperature, the intended beneficial effect of fluoride at sub-optimal levels (below 0.7 mg/l) is lost, so it might just be a waste of fluoride.