If you've ever glanced at the bottom of your water bottle or meal prep container, you may have seen a number printed on the plastic. These numbers are crucial for indicating and understanding the type of plastic you're using — and the potential health risks it may pose.
While more and more research finds that plastics aren't good for us, what does that really mean for our Tupperware? Learn which plastic containers you can safely use and which you may want to toss.
Plastic 1: Polyethylene Terephthalate (PET)
If your soda bottle or peanut butter jar has the number one printed on the bottom, it's a PET container, according to the Sea Studios Foundation. These containers are light-weight, clear and smooth in texture — and intended for single use only.
One of the most easily recycled plastic varieties, PET is commonly used for water or soda bottles, detergent containers and peanut butter jars. Currently, there are no known health issues or concerns associated with this plastic and it is commonly recycled into new bottles or polyester fabric.
Plastic 2: High-Density Polyethylene (HDPE)
Like PET, HDPE is a frequently used, safe plastic container. It's denoted by a number 1 on plastic containers. HDPE products are safe and are not known to transmit any chemicals into foods or drinks, making this plastic a low health risk variety, according to Chemical Safety Facts.
This plastic is most often used for milk or water jugs, laundry detergents and shampoo bottles. Like PET, HDPE is a single-use container and should be properly recycled after use. Typically, these containers are either recycled back into new containers or converted into plastic lumber, pipes, rope or toys, according to the Sea Studios Foundation.
Plastic 3: Polyvinyl Chloride (PVC or V)
While PET and HDPE don't have any associated health risks, PVC (which is denoted by a number 3 on plastic) has been shown to produce harmful chemicals like lead, DEHA and dioxins in manufacturing, disposal or destruction, according to the Sea Studios Foundation.
Exposure to these chemicals may lead to decreased birth weight, learning or behavioral problems in children or hormone disruption. Due to the potential risks PVC poses toward babies and young children, the American Academy of Pediatrics recommends avoiding this plastic in kids' food containers.
PVC is often found in clear food packaging or cling wrap, some plastic squeeze bottles, vinyl pipes and shower curtains. This type of plastic is one of the least recyclable varieties due to the chemical additives.
Read more: The 4-Week Meal-Prep Challenge
Plastic 4: Low-Density Polyethelene (LDPE)
Low-density polyethelene is a generally safe plastic variety that has no known health risks associated with use. However, the manufacturing of LDPE does produce organic pollutants, causing potential harm to the environment, according to the Sea Studios Foundation.
Not usually recycled, LDPE (denoted by the number 4) is most commonly used to package bread or frozen food. Most plastic wraps are also made of LDPE and are intended for single use only.
Plastic 5: Polypropelene (PP)
Polypropelene containers do not leach harmful chemicals into foods or liquids and are not associated with any known health issues. Typically, this plastic is transluscent or opaque in color and has a high melting point, which typically makes these containers microwave or dishwasher safe, according to Chemical Safety Facts.
Type 5 plastic is used to make yogurt containers, cream cheese containers, maple syrup bottles or prescription bottles. Unlike other safe plastics, PP is not easily recycled due to varieties of type and grade, making it difficult to achieve the right consistency, according to the Sea Studios Foundation.
Plastic 6: Polystyrene (PS)
Polystyrene comes in rigid and formed shapes and is denoted by the number 5. While recycling this plastic is possible, it's not generally economically beneficial. Rigid forms of PS plastic are typically found in CD cases or disposable cutlery, whereas formed PS typically comes in the form of styrofoam, including packaging peanuts, egg cartons or building insulation.
Styrene is a chemical that can be released by polystyrene, which may act as a neurotoxin over time and has shown harmful effects on red-blood cells, the liver, kidney and stomach organs of animals, according to the Sea Studios Foundation. When leached from polystyrene, styrene can be absorbed by food and stored in body fat once ingested. Over time, this exposure can lead to accumulation of this chemical in the body.
Plastic 7: Mixed
The number 7 indicates that your container is constructed with a mixed variety of other plastics. Typically, mixed plastics are practically impossible to recycle and pose the most potential health hazards, according to the Sea Studios Foundation. Polycarbonate plastic (often included in plastic seven), leaches bisphenol A (BPA) into food, a known endocrine disruptor. BPA may also create genetic damage and may effect development.
Mixed plastics are typically used to construct lids, medical storage containers, five-gallon water bottles and sports water bottles, among other items.
Read more: 5 Potential Health Hazards of Canned Wine
What To Do About Your Plastic Containers
While certain plastics can be risky, this doesn't mean you have to go and toss all your meal prep containers and water bottles. Here are some steps you can take to safely handle your plastic:
- Avoid heating food in plastic containers
- Wash plastic with a mild detergent
- Opt for glass containers when you can
- Prioritize plastics that are on the safer end of the spectrum (types 1, 2, 4 and 5)
- Avoid using type three plastic with children's food or drink