Health Risks of Excessive Selenium in Drinking Water

Selenium is an essential trace mineral crucial for human health in small amounts, supporting functions like metabolism and immunity. However, when its concentration in drinking water exceeds safe limits (typically above 40 micrograms per liter, as per WHO guidelines), it becomes a significant health hazard, leading to a condition known as selenosis.

The health impacts of chronic selenium overexposure from water include:

1. Gastrointestinal Distress: Early symptoms often include nausea, vomiting, abdominal pain, and diarrhea.

2. Neurological Damage: Numbness, tingling sensations in extremities, lack of coordination, and even paralysis can occur in severe cases.

3. Hair and Nail Problems: Brittle hair, significant hair loss, brittle nails with white spots, and deformed nails are common visible signs.

4. Skin Rashes: Dermatitis and skin inflammation can develop.

5. Fatigue and Irritability: General malaise, chronic fatigue, and increased irritability are frequently reported.

6. "Garlic Breath": A distinctive garlic-like odor on the breath is caused by the exhalation of certain selenium compounds.

7. Liver and Kidney Damage: Long-term exposure can impair the function of these vital organs.

8. Potential Cardiovascular Effects: Some studies suggest links to increased risks of cardiovascular problems.

The severity of symptoms depends on the level of selenium and the duration of exposure. While acute poisoning is rare from water alone, chronic intake of even moderately elevated levels poses serious health risks over time.

Protection is Key: Ensuring drinking water selenium levels are within safe limits is crucial. Regular water testing, especially in areas with known selenium-rich geology, and using appropriate filtration technologies if needed, are vital steps to prevent selenosis and safeguard public health.