Zinc Oxide (chemical formula: ZnO), is a white or yellowish white powder that is odourless, bitter in taste and virtually insoluble in both water and alcohol.
Zinc oxide is used as a bulking agent and a colourant in the production of; rubbers, white paints and enamels, printing inks, white glue, opaque glass, and quick setting cement.
The chemical also acts as both a skin protectant and a UV protectant, making it one of the key ingredients used in many nappy rash creams and sunscreens. It is also found in other cosmetics such as; makeup, nail products, foot powders, soaps and baby lotions. Sunscreens containing zinc oxide are considered ‘physical sunscreens’ as they provide protection by forming an actual physical barrier on the skin, as opposed to ‘chemical sunscreens’.
As zinc is an essential nutrient, it is also added to food (human and animal) and even fertilisers to increase their nutritional value.
Exposure to zinc oxide can occur through eye and skin contact, inhalation and ingestion.
Eye contact with zinc oxide may cause irritation. Repeated exposure may result in inflammation and redness with the possibility of temporary vision impairment.
Skin contact is not thought to have harmful effects, but exposure can still be quite damaging if it enters the bloodstream through open cuts or abrasions. Skin irritation can occur when exposure is prolonged or repeated – this may lead to; mild inflammation, redness and swelling. Prolonged and repeated exposure can also result in acne-like eruptions known as “zinc oxide pox”.
Inhalation of zinc oxide dust and vapours can cause wheezing, coughing and breathing difficulties. People with impaired respiratory function may have their condition worsen if excessive concentrations are inhaled.
Ingestion of insignificant quantities is not thought to be cause for concern, however larger doses may lead to gastrointestinal disturbances such as vomiting, abdominal cramps and diarrhea.
If eye exposure occurs, remove any contact lenses and flush the eye with plenty of fresh running water. Seek medical attention without delay.
In the event of skin exposure; remove all contaminated clothing, footwear and accessories and cleanse the affected area with plenty of soap and water. Contaminated clothing must be washed prior to wearing again. Seek medical attention if irritation occurs.
If zinc oxide is inhaled by a person, remove them from the contaminated area to the nearest fresh air source and monitor their breathing. If they find breathing difficult, provide them with oxygen. If they are not breathing and you are qualified, perform CPR. Seek medical attention.
If zinc oxide has been swallowed, the patient should drink water immediately. First aid is generally not required, but if in doubt, contact, seek medical attention.
Emergency eyewash fountains should be accessible in the immediate area of the potential exposure to the chemical.
Local exhaust ventilation is usually required to remove or dilute any air contaminants.
PPE including; safety glasses with side shields, chemical goggles, PVC overalls, gloves and masks are recommended when handling zinc oxide.