Resin Codes 1–7 on Food Plastic Bottles: Material, Safety, and Recycling Guide

In everyday life, plastic items such as drinking cups, mineral water buckets, plastic tableware, beverage bottles, and baby bottles are everywhere, and they are often heated or reused over long periods. What many people overlook is that these habits may carry a deadly risk—one hidden in the numbers printed on the bottom of plastic bottles.

Numbers 1 through 7 each stand for a different material class; when a product contains several materials, the code indicates its main material. This labeling approach began in the United States and has since been accepted and adopted by many countries, China included. While its primary purpose is to make plastic recycling and reuse easier, it also lets consumers identify the material, intended uses, and suitable conditions for the plastic products they use.

Inside the triangle with arrows, each number has a distinct meaning:

'1' — PET (polyethylene terephthalate): produces carcinogenic substances after 10 months of use.

'2' — HDPE (high-density polyethylene): difficult to clean and prone to bacterial growth.

'3' — PVC (polyvinyl chloride): can produce carcinogens when exposed to high heat and grease.

'4' — LDPE (low-density polyethylene): can produce harmful substances at high temperatures.

'5' — PP (polypropylene): a material specifically for microwave-safe lunch boxes.

'6' — PS (polystyrene): heat- and cold-resistant, but not suitable for microwave use.

'7' — PC and other materials: used for baby bottles and space bottles; however, cups made from this material can easily release the toxic substance bisphenol A at high temperatures, harming human health. Do not heat such cups or leave them in direct sunlight.

Consumers can use the marking graphic on the bottle bottom or in a clearly visible area to determine whether a bottle is reusable. For food packaging, they should choose a qualified plastic bottle with quality and safety assurance, namely QS certification; under the stated conditions of use, consumers can use it with confidence. For bottles without a reuse graphic on the bottom or in an obvious place—such as common mineral water bottles or unmarked bottles—consumers are advised not to reuse them for food. If such bottles have already been reused, low-oil and low-acid foods should be stored at low temperature, and use should be stopped as soon as possible. A reporter's visits to supermarkets and shopping malls found that reusable plastic containers are almost impossible to find.

After recycling, plastic bottles are not allowed to be used for food packaging; if the quality supervision department finds such use, the manufacturer's production license will be revoked immediately. Because recycling and processing change some properties of plastic bottles, they are difficult to turn back into plastic bottles and are mostly used for non-food container products.

— Source note: China Packaging Network (pack.cn), original link: http://news.pack.cn/show-361797.html