Changes of Fluoride Content in Sand From Sandboxes Located on Playgrounds in Police (West Pomerania, Poland)

The aim of the study was to determine fluoride content in sand from sandboxes in Police town (West Pomerania, Poland). This area is exposed to excessive emissions of fluoride compounds because of the proximity of chemical plants. The sand samples were collected five times in a period from March to November in 2016. Fluoride content was determined using the potentiometric method with an ion-selective fluoride electrode. The obtained results showed that fluoride content was ranged from 0.09 to 1.48 mg·kg-1 dm. The lowest fluoride content was recorded in the sand collected in place, which was the closest to the emitter, and the largest in the samples from sandbox, which was furthest from the emitter. Analyzing the changes in the content of this element over time, the largest fluoride concentration of sand occurred in July or September depending on location. Pearson correlation coefficient at p < 0.05 (r = 0.925) showed a significant positive correlation between fluoride content and the distance from fluoride emitter.