Jasmin covered the issues with various types of plastics in baby bottles, but there are also issues to be aware of when recycling. Sustainability engineer Pablo Paster runs those numbers on the bottoms of almost everything plastic, and notes that little of it is actually recycled at all, but "down-cycled," at best.

Rather than using returned soda bottles to make new soda bottles, "down-cycling" refers to their use in making lower-grade plastic products such as park benches, milk crates, and plastic speed bumps. The reason for this is that there are thousands of types of plastic and a huge selection of additives that contaminate the quality of the recycled plastic.

See Pablo's explanation of the different numbers at ::Ask Pablo

Difficulty level: Easy