The case for re-evaluating the upper limit value for selenium in drinking water in Europe

Area of Science:

• Environmental Science
• Toxicology
• Public Health

Background:

• Selenium is an essential trace element vital for human health.
• Excessive selenium intake can lead to toxicity, as the margin between beneficial and harmful levels is narrow.
• Tap water represents a potential source of increased selenium intake.

Purpose of the Study:

• To review methods for establishing safe selenium limits in drinking water.
• To emphasize the importance of considering total selenium exposure from all sources.
• To advocate for geographically adapted selenium limits in drinking water.

Main Methods:

• Overview of approaches for calculating safe selenium intake levels.
• Analysis of World Health Organization (WHO) guidelines for drinking water quality.
• Consideration of total dietary selenium intake (food and beverages).

Main Results:

• The narrow therapeutic window for selenium necessitates careful monitoring of water concentrations.
• European regulations set a limit of 10 microg/l for selenium in drinking water.
• Total selenium intake from food and beverages must be factored into setting safe drinking water levels.

Conclusions:

• Drinking water selenium concentration is a critical parameter for public health.
• Geographically specific risk assessments are needed to adapt selenium limits.
• WHO recommendations support tailoring drinking water standards to local conditions and total intake.