Reduce, reuse, and recycle has been a national mantra for decades. In an effort to shrink our collective carbon footprint, consumers often reuse plastic water bottles.

But is this a safe practice? The answer isn’t black and white.

In this article, we’ll look at the types of plastics used to hold water and other beverages. We’ll also look at the chemicals those bottles may be leaking when reused, and best use options.

Plastic bottles are made from a variety of resins and organic compounds that can be manufactured into synthetic polymers.

Plastic bottles have a recycling code imprinted on them. This code tells you what type of plastic they’re made from.

Plastic codes range from numbers 1 to 7. These designations are designed to help with batch sorting during recycling:

#1polyethylene terephthalate (PET or PETE)
#2high-density polyethylene (HDPE)
#3polyvinyl chloride (PVC)
#4low-density polyethylene (LDPE)
#5polypropylene (PP)
#6polystyrene (PS)
#7other

Not all types of plastics are used to make plastic bottles. Most plastic bottles manufactured today are made from #1, #2, or #7 plastics. Read on to learn about these three types of plastics.

#1 – polyethylene terephthalate (PET or PETE)

Polyethylene terephthalate is the chemical name for polyester. Despite its name, PET doesn’t contain phthalates.

It also doesn’t contain other concerning chemicals, such as BPA. It does contain aldehyde and antimony in small amounts.

Antimony has been found to leach out from plastic bottles into the liquid they contain when the bottle is submitted to heat exposure, such as being left out in the sun, or in a hot car.

Manufacturers design and produce PET bottles as one-time-use only products. Although the Food and Drug Administration (FDA) has approved PET bottles for single use and for reuse, many manufacturers and consumer advocates urge the public to limit their PET bottles to one time use only.

#2 – high-density polyethylene (HDPE)

HDPE plastic is currently considered a low-hazard plastic with a low risk of leaching.

HDPE contains nonylphenol, which has been found to be dangerous to aquatic life. Nonylphenol is also an endocrine disruptor. This means it may affect your endocrine system, which controls your hormones.

It’s important to note that it’s not been definitively proven that nonylphenol can leach out of HDPE bottles. High-density polyethylene is sturdy and designed to ward off bacterial growth. It’s not thought to be affected by heat or sunlight.

Manufacturers use HDPE for large bottles, such as milk jugs and gallon-sized water bottles. These bottles are intended for only one-time use. They’re widely recycled.

#7 – other

Bottles with recycling code #7 are often, though not always, made from polycarbonate plastics or epoxy resins, which contain BPA (bisphenol A).

Small amounts of BPA can leach out of plastic containers into the liquid or food they contain. The FDA has stated that “BPA is safe at the current levels occurring in foods.”

BPA is, however, an endocrine disruptor that’s been linked to multiple health concerns, including:

BPA may also adversely affect children’s behavior and hurt the brain and prostate glands in fetuses, infants, and children.

Use bottles with this code with caution. Never heat or reuse them.

Large containers and bottles designed to hold 3, 5, or more gallons of water are sometimes made from #7 plastics.

If you’re eco-conscious, you’d probably rather reuse plastic bottles than buy new ones over and over again.

While that’s understandable, it may not be the most proactive thing you can do, either for the environment or your health.

Choose an eco-friendly reusable bottle

Plastic bottles aren’t manufactured or designed for ongoing use. If you wish to be eco-conservative, you’re better off buying an eco-friendly water bottle made from recycled stainless steel. Aluminum bottles sometimes have liners that contain BPA.

Healthline

Beware of microplastic contamination

One study analyzed bottled water from multiple manufacturers in several countries. Researchers found that 93 percent of them were contaminated with microplastics.

Microplastics are tiny particles of plastic that leach into liquid or food from the container they’re housed in.

Reusing plastic bottles with codes #1 and #2 is probably fine to do on occasion, provided you take certain precautions.

Unless you know for certain that the #7 bottle you have doesn’t contain BPA, don’t reuse it. You may also wish not to use it at all, even for one-time use.

Watch for cracks, dents, or dings

Plastic bottles of any kind shouldn’t be reused if they show even slight signs of wear and tear, such as cracks or dings. These allow chemicals to more readily leach out of them.

Keep in mind that tears can be microscopic and hard to see. That’s one reason why one-use-only plastic bottles aren’t recommended for reuse.

Don’t let them heat up

Don’t let plastic bottles get hot. This also allows chemicals to leach out more readily.

If you’re using a plastic bottle in hot weather, a hot yoga studio, or in other places that get humid or steamy, throw it away. Don’t expose plastic bottles to direct sunlight.

Wash between uses with warm, soapy water

Plastic bottles should be washed between uses so they don’t harbor bacteria. Use warm (not hot) soapy water. Rinse thoroughly before refilling.

What about bottle caps?

Most bottle caps are made from #2 or #5 plastics. These should also be reused conservatively and washed between uses.

Healthline

Recycling plastic bottles gives them a second life. Recycled plastic can turn into products such as clothing, furniture, and new plastic bottles.

Plastic bottles that aren’t recycled take, on average, 450 years to biodegrade in landfills.

Even though most plastic bottles can be recycled, many of them end up in landfills or incinerators since people don’t recycle them. Many plastic bottles also become litter, clogging our oceans and severely damaging marine life.

Bottles with recycling codes #1 and #2 can and should be recycled. PET plastic bottles are the most recycled type.

No need to sort bottle codes, but do rinse them out

To recycle your plastic bottles, you don’t need to sort them according to their plastic codes. This is done automatically at most recycling centers. You should, however, rinse or wash out your bottles before recycling them.

Check with your local recycling center or with your local elected officials to find out the exact recycling specifications required in your area.

Not all plastic bottles can be recycled

Bottles with recycling code #7 can’t be recycled or reused. Avoiding use of bottles with this code may make sense for you and your family, as well as for the planet and our national economy.

Most plastics weren’t designed to be recycled. With that in mind, a new type of plastic was recently created by scientists at the Department of Energy’s Lawrence Berkeley National Laboratory.

The material is called poly(diketoenamine), or PDK. It can be broken apart at the molecular level and given life in any new form, including a different texture, color, or shape without compromising its initial quality or performance.

This type of material will be easier to sort at recycling centers. It’ll also make recycled materials made from it more durable and of better quality.

If used in a broad-based manner by manufacturers, plastics made from PDK may make plastic waste in landfills and in oceans a thing of the past.

The United Nations estimates around 300 million tons of plastic is manufactured each year. Of that number, more than 8 million tons finds its way into our oceans. There it contaminates coral reefs and kills mammals, fish, and seabirds, who mistake plastics for food.

The manufacturing process for all types of plastic requires vast amounts of energy. Plus, it emits toxins and pollutants into the air, water, and ground water. This contributes to global warming and increases the planet’s toxic load, affecting humans and animals.

Plastic bottles litter our streets, marring the national landscape. They choke our landfills, taking centuries to decompose. If they’re incinerated, they release toxins into our environment that contribute to health and environmental problems.

When you factor in that most plastic bottles are designed for one-time use, the solution is clear: Use fewer plastic bottles. Swap them out for permanent solutions that won’t cause the same level of harm to our environment.

Best practices

  • Always recycle plastics.
  • Take the time to rinse out bottles before recycling.
  • Check with your local recycling center to determine whether bottle caps should be left on or taken off.
  • Make recycling a family practice. Enroll your family in encouraging others to recycle 100 percent of the time at school, at work, and at home.
  • Avoid using plastic bottles whenever possible. Opt for recycled or recyclable options, such as glass, porcelain, or stainless steel.
  • Set an example for your community by picking up and recycling plastic bottles and other types of litter when you see it on the street, beach, or other location.
Healthline

Manufacturers design plastic bottles for one-time use only. They can be reused conservatively, provided they’ve not experienced any wear and tear.

Swapping out plastic bottles for more permanent solutions, such as bottles made from stainless steel, is better for your health and for the environment.