Resin Identification Numbers

Toxic Plastic Ranking and Plastic Classification

Your guide to the types of plastics – their Resin Identification Numbers and toxicity.

The Plastic Family

American Chemistry Council plastic identification numbers:

1. Polyethylene Terephthalate (PET, PETE)
2. High-Density Polyethylene (HDPE)
3. Polyvinyl Chloride (PVC, vinyl)
4. Low-Density Polyethylene (LDPE)
5. Polypropylene (PP)
6. Polystyrene (PS, EPS)
7. Other: when package is made with a resin other than the six listed above, or is made of more than one resin and used in a multi-layer combination

Plastics Ranked According to Toxicity

1. Polyvinyl chloride (PVC, vinyl) and other halogenated plastics
2. Polyurethane (PU), Polystyrene (PS), Acrylonitrile-butadiene-styrene (ABS), Polycarbonate (PC)
3. Polyethylene-terephthalate (PET, PETE)
4. Polyolefins (PE, PP)
5. Bio-based plastics

Category 1, 3, 6, 7 are considered unsafe
(chlorinated plastic) = toxic plastic

Category 2, 4 and 5 are considered safer
'still toxic, just lesser severity'

Labelling

With both classification indexes for the different types of plastics, we are all familiar with the imprint of the plastic number on plastic food containers, plastic packaging, plastic cups, and other plastic products. My question to the design and build industry is why most plastic products from insulation, wall boards, furniture, to paint, textiles and accessories do not clearly have the type of plastic displayed.

The majority of these chemical based plastics still leach and offgas VOCS through the whole product lifecycle. Consumers and design professionals can request the MSDS (Material Safety Data Sheet) from the manufacturer, which details each ‘ingredient’ within the product and any finishes. Why is this information not available freely?