http://demo.rkmsuk.com/MSDS/5%20bitumen.pdfhttp://www.inchem.org/documents/ehc/ehc ... Number:5.7
Material Safety Data Sheet from what sounds like a company that manufactures bitumen. WHO document about petroleum products, including bitumen.
"SKIN: Repeated exposure to hot bitumen or bitumen fumes may cause inflammation of the skin, acne
like lesions, development of horny growths on the skin, darkening of the skin and sensitization of the
skin to light. Bitumen may cause hair loss, dryness, scaling, and dermatitis. May aggravate existing
skin conditions. Bitumen contains chemicals that may have a carcinogenic potential."
There you go. May have carcinogenic material. Everybody start fear mongering. *rolls eyes* (/sarcasm)
Sorry, I think I'm being a bit of an ass here. I work in a medical field and hear these types of conversations all the time, so it gets a little bit tiring to me.
On a serious note, if you're this anxious about it now, you'll likely never be anxiety-free, because no one in their right mind will design a good study to test the carcinogenic potential of exposing a human to bitumen. All the data will be from animal models (which are super artificial) or from retrospective data, i.e. looking back at people who have certain illnesses or have been exposed to bitumen in the past and seeing if there is any correlation.
To that end, if you read the rest of the data sheet or go to the referenced WHO publication, it basically says that if you PAINT (seriously?) the equivalent of 200mg of bitumen to your skin every day for two years, you *might* have a higher chance of cancer. or you might not, depending on which study you listen to. These are based on animal studies.
Looking back at health records of humans who have *worked* in these plants or with asphalt or other of these types of things, there was NO EVIDENCE of increased risk of cancer or decreased lung function. You will note in the details that 1/96 men in one study developed lung cancer - for comparison, ~7/100 americans will be diagnosed with lung cancer per year. I think those 96 men actually did quite well. These data are based on the WHO EHC which i linked. Interestingly, mice who INHALED bitumen DROPLETS did not increase their chances of lung cancer. I know, right?
Now, all said and done, here are the facts thus far
1. bitumen contains carcinogens
2. there is no evidence that bitumen causes cancer in humans (at least that I found, please correct me if i'm wrong, since I'm not going to spend 6 hours reviewing this)
It's up to you which evidence is more important. I always tell my patients that everybody will have their own threshold for OKAY and NOT OKAY. If you're okay spending 8 hours per day x5 years sitting next to a sheet of KNOWN carcinogens, knowing that people have worked 8 hours per day x40 years in harvesting/manufacturing/applying bitumen without adverse health effects, then please go for it. If not, then get another case - you're not losing out on much in the long term.