Teflon, which is known chemically as polytetrafluoroethylene, or PTFE, is a plasticlike substance made up of a complex mixture of perfl uorinated chemicals (PFCs). Unlike known environmental villains such as DDT and PCBs, PFCs are not generally volatile – in other words, they do not become easily airborne and so tend not to migrate long distances. In addition, to produce a substance such as Teflon, these compounds are usually ‘locked’ into polymers – chains of molecules – so it was assumed that they couldn’t leak into the environment. Even if they did, it was assumed that they wouldn’t break down; and even if they did, it was assumed that they were biologically inert. All of these assumptions are being proved wrong.

Scientific data shows that PFCs fulfil every single criterion for persistent bioaccumulative toxins: that is they do not biodegrade, they accumulate in people, animals and the environment, and they have been shown in laboratory tests to be toxic to mammals. Although there are nearly 100 known PFCs, only two have been studied in any depth: perfluorooctane sulfonate (PFOS), a breakdown product of the stain-repellent Scotchguard (now withdrawn from sale), and perfluorooctanoic acid (PFOA), a breakdown product of Teflon. Both have been found in the blood of nearly every human tested, as well as in animals in the Arctic and Atlantic oceans.

Once in the environment, PFCs have been shown to accumulate in organs like the liver, gall bladder and thyroid gland. In primates, including humans, exposure to one of Teflon’s breakdown products, PFOA, has led to an underactive thyroid (hypothyroidism). A prolonged state of hypothyroidism is a risk for obesity, insulin resistance and thyroid cancer.

Laboratory studies also show that PFOA is toxic to at least nine types of cells that regulate immune function. Cells in the spleen and thymus – both critical to immune function – are particularly vulnerable, and humans exposed to PFOA show reduced immune function. Most recently, PFOA has been linked to raised cholesterol and triglyceride (blood fat) levels in factory workers, and in animals to potentially dangerous changes in the size and weight of several important organs such as the brain, liver and spleen. PFOA is also thought to be a hormone disrupter.

In 2005, the US Environmental Protection Agency classified PFOA as a ‘likely human carcinogen’ and asked industry to work towards eliminating PFOA and related chemicals from emissions and products by no later than 2015.

10-20% Distillates (petroleum), hydrotreated heavy naphthenic (C20-C50).
Can be classified as a suspected human carcinogen if it contains > 3% polycyclic aromatic hydrocarbons (PAHs). The chain lube manufacturer did not use the carcinogen classification in the product literature so there is some probability that the PAH concentration is below the limit.

There have been some studies showing toxic effects on adrenals, bone marrow, liver, lymph nodes, kidney, stomach, thymus through prolonged or repeated skin exposure; however I found mention of a study of rabbit skin exposure toxicity LD>5000mg/kg, which is not significantly toxic.

10-15% Short chain chlorinated paraffins (C6-C18)

From an assessment by the Australian National Industrial Chemicals Notification and Assessment Scheme (NICNAS): SCCPs exhibit very low acute toxicity by all three routes in animals. Mild skin and eye irritation were observed in some animal studies. Available human data indicate that SCCPs do not cause skin irritation and are not sensitisers.

1-5% Solvent naphtha (petroleum), light aromatic (C8-C10).

Can be classified as a suspected human carcinogen if it contains > 0.1% benzene. The chain lube manufacturer did not use the carcinogen classification in the product literature so there is some probability that the benzine concentration is below the limit.

My bottom line opinion is that this chain lube, which will be used sparingly and infrequently (i.e. once every few weeks) does not present a significant hazard to the user or to the environment. I'd recommend that you wash if you get any on your skin and certainly don't drink it. Also, do not throw unused portions in the trash.

I have know idea why the LBS dropped the product. Their stated justification does not match reality.