Safety
Citric acid is recognized as safe for use in food by all major national and international food regulatory agencies. It is naturally present in almost all forms of life, and excess citric acid is readily metabolized and eliminated from the body.
Interestingly, despite its ubiquity in the body, intolerance to citric acid in the diet is known to exist. Little information is available as the condition appears to be rare, but like other types of food intolerance it is often described as a "pseudo-allergic" reaction.
Contact with dry citric acid or with concentrated solutions can result in skin and eye irritation, so protective clothing should be worn when handling these materials.
Excessive consumption is capable of eroding the tooth enamel.
Close contact to the eyes can cause a slight burning sensation, and may cause loss of sight.