What are the effects and dangers of Camphor on the human body?

Introduction of Camphor

Camphor is an icterane monoterpene and cyclic monoterpene ketone made by steam distillation of the bark and wood of the camphor tree, and has many biological properties such as insecticidal, antibacterial, antiviral, anticoccidial, anti-injurious, anticarcinogenic, and cough suppressant. It has been used to treat toenail fungus, warts, insect bites, cold sores, piles and osteoarthritis. Camphor is applied to the skin to increase local blood flow and acts as a "counter-irritant" to reduce pain and swelling by causing irritation. Some people apply camphor to the skin to treat airway disorders and to treat heart conditions. Camphor is also used as an ear drop and to treat minor burns. However, camphor should not be applied to broken skin because it can enter the body quickly and reach concentrations high enough to cause poisoning.

Effects and Dangers

Camphor is probably safe for most adults when applied to the skin in low concentrations in creams or lotions. Camphor can cause some mild side effects such as skin redness and irritation. When inhaled in small amounts as part of aromatherapy. Do not use more than 1 tablespoon of camphor solution per quart of water. Camphor is not safe for oral use in adults. Ingestion of camphor can cause serious side effects, including death. The first symptoms of camphor poisoning occur quickly (within 5 to 90 minutes) and may include burning of the mouth and throat, nausea, and vomiting. Other symptoms can affect the nervous system, such as seizures, confusion and muscle contractions, as well as effects on vision.

Serious pediatric toxicity resulting from exposure to small amounts of camphor-containing products has long been a problem. Twenty years ago the United States Food and Drug Administration took several actions in an attempt to ameliorate this risk. Despite these changes, camphor remains commonly available in many nonprescription vaporized or topical “cold” medications, topical musculoskeletal anesthetic “rubs” and “cold sore” preparations, though its efficacy is largely unproven. Data from the American Association of Poison Control Centers demonstrate that camphor continues to be a common source of pediatric exposures. A review of the literature reveals persistent reports of toxicity resulting from exposure to relatively small amounts. In the pediatric population, exposure to as little as 500 mg is cited as a cause of mortality. More commonly, 750 to 1000 mg are associated with the development of seizures and death. Currently available products with 10% camphor contain 500 mg in 5 mL. It is concluded that small doses are dangerous. In children less than 6 years of age, exposure to 500 mg or more requires rapid triage to the closest health care facility.

Camphor remains a product with the potential for serious toxicity in the pediatric patient. One mouthful (9.3 mL) of several currently available products has the potential to cause serious morbidity and even death. Exposures estimated to be 500 mg or greater should be triaged to a hospital by ambulance and observed until 3 h post-ingestion before medical clearance is given

References:

[1] JEFFREY N LOVE MD Janet S M Maura Sammon MD. Are one or two dangerous? camphor exposure in toddlers1[J]. Journal of Emergency Medicine, 2004, 27 1: Pages 49-54. DOI:10.1016/j.jemermed.2004.02.010.

[2] WEIYANG CHEN Alvaro V, Ilze Vermaak. Camphor–a fumigant during the Black Death and a coveted fragrant wood in ancient Egypt and Babylon–a review.[J]. Molecules, 2013, 18 5: 5434-5454. DOI:10.3390/molecules18055434.