cancer risk?

Question

Do you think the one in a million cancer risk standard used to estimate safe levels for environmental lifetime exposure to possible carcinogens is sensible? Give reasons.

Answer 1

There are many factors that are not considered when looking at a simple dose standard for determining risk. Here are a few examples:

1) Biochemical individuality (genetic variation, variation in detoxification abilities, etc.)

2) Synergistic effects of other toxins co-existing in the subject (e.g. a person can be exposed to 5 different chemicals/toxins at the same time, each at a 'safe' level, but the combined effects may be very toxic)

3) Nutritional status - can have a major impact on absorption (e.g. low calcium intake results in increased lead absorption after lead exposure), detoxification, protection against tissue/DNA damage, DNA repair abilities, etc.

4) Other health issues can increase susceptibility to a specific toxin (e.g. a co-existing chronic disease, chronic infection, chronic inflammation, etc.)

5) Timing of exposure (e.g. exposure in utero, infancy, pre/post-menopause, etc. may have drastically different effects)

6) Intensity/duration of exposures (e.g. a few large doses vs. steady, low doses).

Best wishes and good luck.

Answer 2

With all the carcinogens in our air and water, we have to have some kind of standard. If you mean one person in one million will get cancer from a certain kind of carcinogen in the environment, it is better than no standard. And no standard, or some politically correct standard that increases the profits of already wealthy people who could give a damn, is what has brought us to your question in the first place.
Now if you mean one part in one million, say for water or air, that is another thing. One part in one million of certain molecules could mean death to millions depending upon the type of toxic molecule and in which environment it is placed.
There are no safe levels of any toxic molecule; one atom of plutonium in your lungs marries you to cancer, end of story, case closed, that is all she wrote.

Answer 3

Just to throw something out there, studies show that exposure to synthesized substances (by man) shows no significant risk increase compared to exposure to naturally occurring substances.