Guide to Plastic Safety: What You Need to Know About Plastic Resin Codes

The truth about plastic resin codes

Many of us have seen those plastic resin codes beneath plastic containers—you know, those little numbers within triangles? In fact, there are a handful of myths surrounding what those codes are supposed to be. One myth claims that they’re supposed to tell you if a certain plastic is microwaveable. Another myth claims that the numbers tell you for how many years you can use the container.

To set things straight, those codes don't really indicate such things. Plastic containers are marked with these resin codes just so that recyclers would know what type of plastic a particular bottle or vessel is made of. It makes the task of segregating plastics faster for recycling.

 

What’s so bad about plastic?

As a parent, it’s important for you to know that checking the resin code is also a good way to determine which plastic containers are safer for your family, especially your children. This is because some of the plastic containers produced for household use actually contain harmful substances. For instance, dangerous plasticizers are often added to plastics to improve their “plasticity.”

Phthalates are among the most common plasticizers added to plastics because they increase the final material’s flexibility and durability. However, recent studies have shown that phthalates are dangerous endocrine disruptors. Endocrine disruptors are chemicals that act like natural hormones; but by imitating hormones, they disrupt the body’s endocrine system and cause problems like birth defects as well as physical and mental developmental disorders.

There are many other chemicals added to plastics that act as endocrine disruptors or cause other serious illnesses like cancers. It is therefore important that you familiarize yourself with the dos and don’ts of plastic use before buying and using plastic dinnerware for your family or plastic lunchboxes and water bottles for your kids.

 

Click here to learn more about plastic resin codes and what numbers to avoid.

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Read on to learn more about plastic resin codes and what numbers to avoid.

Plastic resin numbers to avoid: 7, 3 and 6

1. Plastic resin number 7 is the category that includes polycarbonate (PC), the plastic material that contains the dreaded chemical, bisphenol-A (BPA). BPA is also an endocrine disruptor, which has been discovered by the U.S. National Institutes of Health to have an effect on a baby’s brain development and behavior. A 2008 study by researchers from the Yale School of Medicine also discovered that BPA can interfere with brain functions that are important to memory, learning and mood.

Although not all resin number 7 plastics contains BPA, it is still wise to avoid them altogether. You really can't be sure what a resin number 7 plastic container is made of because it is the “others” category in the resin code system. It is an umbrella code for all plastics that don’t fall under resin numbers 1 to 6. One resin number 7 plastic that is regarded safe, though, is polyactide (PLA), which is a biodegradable plastic made from corn.

 

2. Vinyl chloride is another dangerous chemical, and it is found in plastic resin number 3 or polyvinyl chloride (PVC) plastic. The U.S. Environmental Protection Agency warns that vinly chloride is an environmental pollutant that can cause permanent or incapacitating ailments (e.g. liver cancer) in people. In addition, people who burn plastic items should be warned that burning polyvinyl plastics releases dioxins, which are known to cause immune system suppression, reproductive disorders and cancer.

 

3. Another material that contains suspected carcinogens or cancer-causing chemicals is plastic resin number 6 or polysterene (PS) plastic, which is made using chemicals like butadiene, benzene and styrene.

 

Click here to learn more about the safest plastic resin numbers.

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Read on to learn more about the safest plastic resin numbers.

The safest are plastic resin numbers 1, 2, 4 and 5

Plastic resin number 1 or polyethylene terephthalate (PET), plastic resin number 2 or high density polyethylene (HDPE), plastic resin number 4 or low density polyethylene (LDPE), and plastic resin number 5 or polypropylene (PP), are currently considered safe for use and are not known to leach any carcinogenic chemicals or endocrine disruptors. Of course, you should always try to be up-to-date with the most recent scientific studies that may dispute the safety of these plastics.

 

Additional Safety Tips

• Never assume that a plastic container is microwave or dishwasher safe. ANY plastic container is bound to change chemically, degrade and release chemicals when heated. If you need containers that you intend to heat in any way, choose heat-resistant glassware like those made from borosilicate (e.g. Pyrex) instead.
• Never boil your baby’s plastic feeding bottles or sippy cups. Just use warm water, or if you intend to sterilize by boiling, choose heat-resistant glass bottles instead.
• Throw away all plastic containers which have become scratched or cloudy from frequent use. They are more likely to release dangerous chemicals.
• Avoid consuming canned food and drinks. The cans of products like powdered baby formula, sardines and fruit juices have liners that are made from plastics with BPA.

Although it is advisable to avoid using plastic containers altogether, this may not be entirely practical. The best thing to do is to learn which of these plastics are safer for use and which ones you’re better off avoiding.

 

Photo from flickr.com