Comparison of Adjusted Fluoride Concentrations Between Water Treatment Facilities and Endpoints in Alberta, Canada.

OBJECTIVES: This investigation aimed to determine whether fluoride concentration in water at the user endpoint remains the same as at the adjusted source, i.e., water treatment facilities. METHODS: Daycares in Alberta, Canada, were used as the endpoint to measure fluoride concentration. They were randomly selected from a list of 400 licensed daycares provided by the Ministry of Children's Services. All water samples collected from the daycares were sent to the accredited Alberta Centre for Toxicology (ACFT) for analysis within 7 days of collection. ACFT used ion chromatography to determine fluoride concentration levels. Statistics analyses were conducted using the software SPSS 25. RESULTS: Water samples were collected from 141 daycares in 35 municipalities. In municipalities that adjust fluoride content, public water is supplied by 8 Alberta Environment & Parks regulated water systems. Fluoride concentration in water samples examined at the endpoint ranged from 0.58 mg/L to 0.79 mg/L. The differences between fluoride concentration at the water treatment facilities and the daycares ranged from -0.03 to 0.22 mg/L. CONCLUSIONS: This study confirms that the concentration of fluoride adjusted at water treatment facilities in Alberta is maintained at endpoints at the approximate optimal level of 0.7 mg/L.

The prevalence and levels of enteric viruses in groundwater of private wells in rural Alberta, Canada.

The prevalence and levels of enteric viruses in untreated groundwater of private wells used for drinking and/or agricultural practices in rural Alberta were studied using the qPCR panel assay, integrated cell culture with qPCR and cell culture in the volume of 500 liters per sample through serial sampling. Seven viruses were assessed including adenovirus, rotavirus, norovirus, astrovirus, sapovirus, reovirus and JC virus. Five viruses were detected with an overall positive detection rate of 6.33 % (45 of 711 samples). The most frequently detected virus was adenovirus (48.9%, 22/45) followed by rotavirus (44.4%, 20/45), reovirus (20%, 9/45), JC virus (6.7%, 3/45) and norovirus (6.7%, 3/45). There was no significant difference in the positive detection rates, ranging from 1.1% to 3.4% by various well settings used for broiler farms, cow/calf farms, feedlots and rural acreages. Effects of well characteristics (aquifer type, well depth, static level of water, well seal) and well completion lithology on potential viral contamination of groundwater of private wells were also analyzed upon available data. The findings demonstrate that occurrence of enteric viruses is low and viral contamination is sporadic in groundwater of private wells in rural Alberta. Conventional fecal bacterial indicators (coliform and/or E. coli) were not a representative marker for viral contamination in groundwater wells in rural Alberta.