We all think of over-the-counter-sports creams as safe to use. They can be easily picked up at the local drugstore and because they are topically applied, they are often applied excessively to areas of injury and pain.

But, did you know that one of the common MAIN INGREDIENTS in sports creams can be hazardous and even fatal if used liberally enough to cause an overdose? The ingredient, Methyl Salicylate, is responsible for one known death and many other cases of toxicity. And this is just one of many dangerous chemicals found in sports creams. Other problematic chemicals include petroleum, propylene glycol, triethanolamine, sodium lauryl sulfate, and polysorbate-80.

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Since chemicals absorbed through the skin are not broken down by enzymes and removed, they tend to accumulate over time. And it’s the gradual, cumulative effects of long-term, repeated exposures that are the real concern. And this isn't new-age mumbo jumbo. In 2007 Arielle Newman a 17 year-old cross-country runner from Notre Dame Academy, NY, died from an accidental overdose of methyl saclicylate (the minty scented ingredient found in products like Icy Hot, Tiger Balm and Ben Gay). It was determined that her body had absorbed a toxic amount of this ingredient as the chemical was absorbed over time by repeated use.

Remember that your skin is your largest organ, and absorbs a great deal of what is applied to it --ever wonder why bioidentical hormones are often given in the form of a topical cream? Because they are absorbed quickly! Take some extra precautions when it comes to what you are slathering on your skin-- check out these potentially harmful chemicals that are common ingredients of OTC sports creams.

Methyl Salicylate

Methyl Salicylate is a chemical relative of aspirin and both drugs belong to the anti-inflammatory analgesics known as salicylates. Methyl Salicylate is more toxic than aspirin and is dangerous to consume orally. This information should give us a head’s up. Arielle’s death shows us that if enough of this chemical is absorbed through the skin, then it is possible to reach toxic levels by topical administration as well. The chemical enters the bloodstream through the organ of the skin and both heat and exercise (which increase the blood circulation) increase the absorption of methyl salicylate.

Unfortunately, even many medical professionals do not realize how easily methyl salicylate enters the bloodstream after being topically applied to the skin—even though the toxicity of oral ingestion of the chemical IS well know in the medical community, including pharmacists and poison control professionals. The warning signs of overdose are the same whether the chemical is absorbed through the skin or orally ingested. Signs of overdose of methyl salicylate are: tinnitus (ringing in the ears), stomach upset, rapid breathing, agitation, irregular heartbeat, nausea, dizziness and convulsions – and, if not immediately treated can lead to heart failure, respiratory arrest and death.

Petroleum

Many analgesic sports creams also contain petroleum products. Petroleum based ingredients like the paraffin petroleum can have negative side effects including finding the petroleum byproduct in breast tumors, suffocation of the skin, premature aging and aggravated acne.

Also, Petroleum jelly and oils are designed so that they remain on the surface of the skin and cannot penetrate very deeply (if at all) into the subcutaneous tissue. So, unless your injury is limited to the surface area of the skin, oil-based formulas cannot make contact with the injured cells.

***Ingredients of Ten of the Most Popular Analgesic Sports Creams on the Market***

Propylene Glycol

Propylene glycol is a form of mineral oil, an alcohol produced by fermentation of yeast and carbohydrates. The form most pertinent to this article is the pharmaceutical grade. Although less concentrated than industrial grade propylene glycol–which is used as an active ingredient in engine coolants and antifreeze, airplane de-icers, polyurethane cushions, and paint products– the pharmaceutical grade is still controversial because it is ingested or applied topically. The pharmaceutical grade of propylene glycol has been found to provoke allergic reactions in people with eczema and other skin allergies, even in formulations of much less than 50%. The FDA lists the following as effects of overdose: metabolic acidosis, lactic acidosis, acute tubular necrosis, allergic contact dermatitis, hemolysis, central nervous system depression, seizures, arrhythmias, and nephrotoxicity.

Triethanolamine

Many popular sports creams contain triethanolamine, which is considered a moderate hazard ingredient by the Cosmetics Database. According to the U.S. National Library of Medicine, the Association of Occupational and Environmental Clinics, and cosmetic Ingredient Review, strong evidence exists that triethanolamine is “a human skin, immune system, and respiratory toxicant.” It has been shown in animal studies to affect the sensory organs at very low doses (especially when used around the mouth, eyes and lips) and to show positive mutation results on mammalian cells. Triethanolamine has also been shown to cause liver and bladder cancer and testicular changes.

Polysorbate-80

The Cosmetics Database reports concerns about Polysorbate 80 being linked to cancer, developmental and reproductive toxicity, organ toxicity and neurotoxicity. In 2006, animal studies showed reproductive effects at very low doses and in vitro tests on mammalian cells showed positive mutation results.

Sodium Lauryl Sulfate

Sodium Lauryl Sulfate is a surfactant, detergent, and emulsifier commonly used in topically-applied products and in industrial cleaners. It is unfortunate, to say the least, that this product is still being used in topically-applied products for humans because nearly 16,000 studies confirm the toxicity of this chemical.

The Environmental Working Group’s Skin Deep: Cosmetic Safety Reviews states that research on SLS has demonstrated links to:

Irritation of the skin and eyes
Organ toxicity
Developmental/reproductive toxicity
Neurotoxicity, endocrine disruption, ecotoxicology, and biochemical or cellular changes
Possible mutations and cancer

What's the bottom line here? READ the label of what's in your sports cream!