Global analysis and prediction of fluoride in groundwater

Abstract

The health of millions of people worldwide is negatively impacted by chronic exposure to elevated concentrations of geogenic fluoride in groundwater. Due to health effects including dental mottling and skeletal fluorosis, the World Health Organization maintains a maximum guideline of 1.5 mg/L in drinking water. As groundwater quality is not regularly tested in many areas, it is often unknown if the water in a given well or spring contains harmful levels of fluoride. Here we present a state-of-the-art global fluoride hazard map based on machine learning and over 400,000 fluoride measurements (10% of which >1.5 mg/L), which is then used to estimate the human population at risk. Hotspots indicated by the groundwater fluoride hazard map include parts of central Australia, western North America, eastern Brazil and many areas of Africa and Asia. Of the approximately 180 million people potentially affected worldwide, most reside in Asia (51–59% of total) and Africa (37–46% of total), with the latter representing 6.5% of the continent’s population. Africa also contains 14 of the top 20 affected countries in terms of population at risk. We also illuminate and discuss the key globally relevant hydrochemical and environmental factors related to fluoride accumulation.

Riboflavin Attenuates Fluoride-Induced Testicular Injury via Interleukin 17A-Mediated Classical Pyroptosis

“…The World Health Organization recommends a maximum limit of 1.5 mg/L of fluoride in drinking water. 33 And the maximum limit for fluoride in drinking water in China is 1.0 mg/L. 34 Therefore, we treated mice with 100 times the human dose (100 mg/L NaF).…”

“…To investigate whether IL-17A regulates fluoride-induced testicular pyroptosis, a riboflavin intervention in a fluoride-treated IL-17A –/– C57BL/6J mouse model was established. The World Health Organization recommends a maximum limit of 1.5 mg/L of fluoride in drinking water . And the maximum limit for fluoride in drinking water in China is 1.0 mg/L .…”

Groundwater Quality and Health: Making the Invisible Visible

“…Geogenic substances are released from the aquifer matrix due to long-term water–rock interactions. ,, The types and concentrations of geogenic substances in groundwater depend on the sedimentogenesis and hydrobiogeochemistry of aquifer systems. , The geogenic substances of most concern include As, F, and I, and groundwater contamination by these substances has been a global problem which threatens the health of several hundreds of millions of people. ,,,,− In China, about 80 million people were influenced by using high F groundwater as the source of drinking water supply, and about 19.6 and 31 million people were exposed to high As and I groundwater, respectively . The high As groundwater in southeast Asia has attracted global concern because it has caused serious health problems among the local people. − Other geogenic substances such as U, Cr, Se, and ammonium in groundwater have been studied in recent years., − When the concentrations of geogenic substances exceed the safe levels recommended by the World Health Organization (WHO) or local governments, the groundwater is deemed to be harmful.…”

Inorganic Hydrogeochemistry in the 21st Century

“…Applications of ML to hydrogeological sciences had largely been limited to physical hydrology, but the last few years have seen a surge in applications to hydrogeochemistry, including the prediction of arsenic, fluoride, manganese, and general solute concentrations (Podgorski and Berg 2020; Erickson et al 2021; Stackelberg et al 2021; Podgorski and Berg 2022; Wood et al 2022). Many ML tools are now available.…”