Balancing chemical equations is a key chemistry skill. Use these step by step instructions to write and balance chemical equations. Balancing chemical equations is a key chemistry skill. Use these step by step instructions to write and balance chemical equations.
So, there are many signs and symptoms of Selenium Overdose- some occur very early and some occur much later. 1  Early Signs: Some of the early signs of Selenium Toxicity are endocrine hormone disturbances- particularly thyroid issues. Poor hair and nail growth are early signs that are probably the easiest to notice.
Selenium toxicity usually occurs from industrial exposure to selenium and not by taking dietary supplements, but it is possible to ingest too much selenium if you regularly take large doses. Speak with your doctor before taking large doses of any dietary supplement, including selenium, and follow the directions on the product label. Sources: