Author Institution: Department of Community Dentistry, School of Dentistry, and Department of Biology, Case Western Reserve UniversityOhio like several other states in the US is mandated by law to optimally fluoridate all public water systems serving over 5000 people. The purpose of this study was three-fold: 1) to determine if Ohioans on public water supplies are receiving optimally fluoridated water, 2) to determine the knowledge level of water treatment plant operators who fluoridate drinking water, and 3) to compare small and large water treatment plants. A pre-tested survey was sent to all 224 water treatment plants that adjust the fluoride concentration of drinking water in Ohio. A 100% response rate was accomplished, with 93 small and 131 large water treatment plants responding. A z-test was computed to compare proportions between small and large water treatment plants. Significance was assessed at p <0.05. Nearly 90% of water treatment plant operators correctly identified the optimal fluoride level, however almost 30% used incorrect means of determining the optimal level. Approximately three-quarters of the water treatment plant operators were able to maintain the fluoride concentration to within 0.1 mg F/L of their optimal level. A significantly greater proportion of large water treatment plant operators were able to maintain a fluoride concentration to within 0.1 mg F/L of their optimum level when compared to small water treatment plant operators (83.2% vs 60.2%, z = 3.60, p <0.05). Most water treatment plant operators are knowledgeable concerning fluoride levels, however small water treatment plant operators may need additional technical assistance to reach the level attained by large plants
