虽说未精炼的原油毒性不是很强，但还是很重的。如果它包裹住鸟翼，将最终会使鸟窒息。

Although unrefined crude isn't very toxic, it's heavy, and if it coats the wings of birds, it will eventually smother them.

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图为污水池里的油砂残渣，其中混有沙子、污水以及萃取未精炼的石油产品后所残留的有毒化学物质。

A containment pond holds tar sands tailings, consisting of a mixture of sand, water, and toxic chemicals that remain after the unrefined oil products have been extracted.

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