http://www.treehugger.com/files/2010...l-debunked.php
<i>"Natural" doesn't always mean good, despite what the marketing people would like you to believe. Arsenic, lead and mercury are as natural as can be, but you wouldn't want them in your food or your living room. Well, crude oil is also natural, but it's toxic to most living organisms (exceptions are rare, mostly bacteria), and the waters of the Gulf of Mexico are the living room and fridge of countless species.
These ecosystems haven't evolved in contact with oil, in the same way that most of the heavy metals found deep in the Earth's crust are toxic to us because over evolutionary time we haven't been exposed to them much. It's the same basic principle that explains why oxygen is toxic to certain microorganisms because they evolved in places where there's little or no O2.
Second Level
And while the oil itself might be "natural", the spill itself certainly isn't. That oil was sequestered deep underground and has been there for millions of years. It very probably wasn't going anywhere until we drilled there. In that regard, it's 100% a human-made disaster.
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