Could the region you live in prevent or precipitate kidney stone formation due to mineral intake through tap water? An analysis of nine distribution regions in Flanders

Objectives: To analyse the mineral content of tap water in Flanders and assess if the region one lives in could prevent or precipitate stone formation due to a difference in mineral content. Methods: Data from six water companies providing tap water to nine regions in Flanders regarding calcium, magnesium, potassium, sodium and sulphate content in tap water was retrieved. Minimum and maximum values were collected and compared between the different geographical regions. Results: The highest calcium level was found in region 9 with a value of 157.0 mg/L, which is almost 10 times the value found in region 8 (16.1 mg/L). Region 6 had the highest magnesium (31.8 mg/L), potassium (30.5 mg/L), sodium (126.6 mg/L) and sulphate (218.5 mg/L) levels. The lowest level of magnesium (2.7 mg/L) was found in region 1, which was almost 12 times lower as in Region 6. Region 9 had the lowest level of potassium (1.5 mg/L), which is a factor 20 lower than Region 6. The lowest sodium and sulphate levels were found in region 8 (6.8 mg/L and 3.0 mg/L), respectively. The difference between the highest and lowest level of sulphate was a factor 70. Conclusion: There is a broad range in the minerals found in tap water between the different production sites in the nine distribution regions in Flanders. However, due to the high standards tap water has to meet in Flanders, the region one lives in will not lead to a higher or lower risk of kidney stone formation if the advised 2 to 3 L per day are consumed.