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.
Symptoms of overdose. 1  Change in consciousness. 2  decreased awareness or responsiveness. 3  difficulty with breathing.  lack of muscle 1  tone. lightheadedness.  loss of 1  consciousness. pinpointed pupils of the 2  eyes. severe sleepiness.  shortness of 1  breath. slow or irregular heartbeat.  unusual tiredness.