It's a refined mineral oil, which is a colourless and odourless substance, and it's related to petroleum jelly. We don't know where it came from and we need to do a lot more testing on this substance to try and track it back to its source. There are people speculating it could be from a ship, that's possible but we just don't know yet. We need to look at what happened and if appropriate take legal action and also, frankly, shame the people.
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