The Chinese have quite the problem with exactly that. Eating something pulled out of a sewer tends to have health effects and gutter oil is sometimes made from

The Chinese have quite the problem with exactly that. Eating something pulled out of a sewer tends to have health effects and gutter oil is sometimes made from grease from a sewer. https://en.wikipedia.org/wiki/Gutter_oil https://en.wikipedia.org/wiki/Gutter_oil