Here's a link for a safety data sheet for a conventional 'cutting oil' used in metal working. There are a few different types of cutting oil but this one seemed the least safe. It contains 'mineral oil' plus a few additives. It's probably best to wash the scrubbing pad with acetone and then water but this cutting oil does not appear to be very hazardous in small quantity.

[URL unfurl="true"]http://www.herchem.com/CanadianENGMSDS/MSDS336%20Dark%20Cutting%20Oil.pdf[/URL]