It's all in the RISK
If you don't know it already, let me be the first to tell you:
There is no doubt that most/all petroleum products and/or raw petroleum contain(s) chemicals which can cause/induce cancer or other medical problems in humans and other of God's creatures under the right exposure and duration conditions. The EPA and other regulatory agencies have wrestled with this for decades.
It is a tough balancing act to
protect people from hazardous materials while at the same time allowing people
to use fuels in automobiles and lawn equipment, allowing mechanics to
work on cars and other vehicles, etc. Pushed to the limit, the EPA
could require every one of us to walk around in "moon suits" all of the time and to so equipment our children on the playground.
The question always is "Where do we draw the line?"
Such is the duty of
"industrial hygienists" to determine.
Similarly, everyone knows that chlorinated solvents can cause cancer, yet we still allow people with little or no education in the matter to clean cloths with "dry cleaning fluids". And we still use dry cleaning solvents to clean electronic parts, circuit boards, etc. We still use these solvents for engine cleaning, tools cleaning, etc.
There is always the balance of benefit versus risk that no one has been able to figure out.
I have no doubt that many of the cancer cases you mention were either caused by the petroleum that was released AND/OR the chemicals that were used to deal with the cleanup. The problem is: What was the percentage of cancers due to this effect, how much to that effect, how much was due to something else, etc.?
It is almost impossible to sort this all out in a rigorous manner and the cost of doing so would be over-whelming. It is sort of like trying to figure out who passed gas at a church benefit when everyone is denying blame and pointing to others.
Sorry for the crude analogy.
Comments from Alaskan newspaper,