A long time ago we outlawed containers trucks that carry food liquids (orange juice for example) from carrying other non-food chemicals, even with truck washing. China just does not have those standards.
You can bet a delivery of orange juice for packaging from a truck in China has plenty or residue from whatever was carried in the tanker truck on the previous load. And they are not meticulous about washing them out. I've seen the process first hand there.
Good Lord!!!!!!!!