Hydroquinone is a granular white solid organic compound with the chemical formula C6H4(OH)2. In addition to being produced synthetically, it occurs naturally in the environment in certain beetles, bushes and mushrooms.
The compound has been found to be carcinogenic in rats when taken orally, however there has been no research to indicate carcinogenic effects of hydroquinone in humans.
Hydroquinone is used across the beauty, photography and oil industries.
It is used in the development of photos as well as being found in; foods, oils and greases as an antioxidant. In beauty, it is used to remove pigment from the skin in topical products to treat hyperpigmentation (liver spots, freckles, “age spots”) and melasma. It works by blocking melanin production but is a somewhat controversial chemical for this purpose. Whilst not readily available in Australia, hydroquinone is banned in Europe, the UK and Japan as it can cause skin irritation as well as other side effects.
The routes of exposure for hydroquinone include; inhalation, ingestion and skin and eye contact.
Inhalation of hydroquinone may produce inflammation and irritation of the respiratory system. People with already compromised respiratory function (conditions such as emphysema or chronic bronchitis), may suffer further disability upon inhalation. Other symptoms may include; perspiration, intense thirst, nausea, vomiting, diarrhoea, hyperactivity, falling blood pressure, stomach pain, convulsions, coma, excess fluid in the lungs and more. Respiratory and kidney damage may follow.
Ingestion of 1 gram of hydroquinone caused ringing in the ears, nausea, dizziness, feelings of suffocation, increased respiration rate, vomiting headaches and collapse. Death by central respiratory failure has followed after ingestion of 5-12 grams of the chemical.
Hydroquinone produces severe skin irritation when exposed to the skin. It has been known to cause severe inflammation and irritation characterised by redness, swelling and possible blistering, which may be present beyond 24 hours of the initial exposure. Entry into the bloodstream through open cuts or wounds may lead to other harmful effects on the body.
Eye exposure may cause mild to severe eye irritation with symptoms including redness, pain and blurred vision. Permanent eye injury is also a possibility.
If inhaled, remove the person from the contaminated area to the nearest fresh air source and monitor their breathing. Seek medical attention if symptoms persist.
If swallowed, urgent hospital treatment is likely to be needed. If medical attention is more than 15 minutes away (or unless instructed otherwise), induce vomiting with fingers down the back of the throat. This should be only performed if conscious and the patient should do this leaning forward or on their left side to prevent aspiration.
If skin exposure occurs, remove all contaminated clothing, footwear and accessories and cleanse the affected area with plenty of soap and water. Contaminated clothing should be washed prior to wearing again. Seek medical attention if symptoms persist.
If the chemical makes contact with the eyes, flush the eyes out immediately with fresh running water, remembering to wash under the eyelids. Removal of contact lenses should only be done by a skilled individual. Seek medical attention if symptoms persist.
Safety showers and emergency eyewash fountains should be accessible in the immediate area of the potential exposure to the chemical and there should always be adequate ventilation (install local exhaust if necessary).
The PPE recommended when handling hydroquinone includes; safety glasses with side shields, chemical goggles, protective gloves, a dust respirator, a PVC apron, overalls and boots.
Do not eat, drink or smoke when using hydroquinone.