" Only forest fires produce more black carbon than bunker fuel. Bunker fuel can have a sulfur content of up to 45,000 parts per million (ppm). Low-sulfur diesel for cars is supposed to contain 10 ppm. The sulfur is converted into acid "

― Rose George , Ninety Percent of Everything: Inside Shipping, the Invisible Industry That Puts Clothes on Your Back, Gas in Your Car, and Food on Your Plate