“Was not their mistake once more bred of the life of slavery that they had been living?—a life which was always looking upon everything, except mankind, animate and inanimate—‘nature,’ as people used to call it—as one thing, and mankind as another, it was natural to people thinking in this way, that they should try to make ‘nature’ their slave, since they thought ‘nature’ was something outside them” — William Morris


Thursday, November 29, 2012

Cultures of Energy Liveblog 6

The heavy PAH's are supposed to pose no risk to human health

But aging of crude reduces acute toxicity; the aromatics with a greater molecular structure are toxic increasingly relative to the number of carbon rings
It was thought they were not biologically available
but after Exxon Valdez << decline in fishing population there were new studies

many multi ringed compounds >> long term negative effects because they do become biologically available

3 to 5 ring PAH's metabolize as plastogens: they rearrange sections of chromosomes

so more rings are not more benign...

chronic long term sublethal effects increase with time not diminish, especially with heavier ones

scientists: complexity of these hydrocarbons
the metabolites of distinct PAH's depend on the organ, development, size, etc. Very interactive

multi ringed compounds >> questioning protection of scientific knowledge
cf tobacco industry
petroleum industry not innocent here: 1775 chemicals in fossil fuels and cancer link!
1930s hydrocarbons <> leukaemia
50 years of manufacturing uncertainty to stall regulation

>> production of constrained certainty
to foreclose the need for further research
insistence on the heavy rings' inertia

>> demonstrated that crude TPH level of 67 000ppm not deleterious...
>> reduce need to analyze sites

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