Are Glass Bottles Better Than Plastic?

Yes. Here’s why.

In the 1970s, plastic revolutionized beverage containers. They were everything that glass bottles were not. They were less expensive to transport, did not break, and were lighter for consumers to carry. It was an easy pick between the two and plastic bottles steadily replaced glass bottles.

Plastic is also very cheap to manufacture, thus saving business owners considerable money. Plastic became a win for both consumers and retailers. However, we didn’t then realize what this transition meant for the environment.

Oil vs Sand

Most plastic bottles are made of PET, also known as polyethylene terephthalate. It’s what makes them durable, light, and useful for holding various edible items such as beverages, ketchup, mustard, and more. To make these bottles, plastic pellets are heated to 500 degrees Fahrenheit then injected into molds.

What exactly is PET? PET is technically polyester – yes, the one used for making clothes. It is a widely used material for food and beverage containers as well as non-food products like shampoo. PET is made using natural gas and crude oil which are both non-renewable resources.

The main component of glass is sand, whether it’s borosilicate glass or soda-lime glass. Bottles are usually made from soda-lime glass; the same type as your drinking glasses (not mugs or tea cups, which are ceramic).

Clear, green, and brown glass can all be recycled, although separately; automation takes care of this. After the glass is crushed it is run through a sorter which can differentiate and filter the colors.

Manufacturing Pollution Footprint

Every year millions of barrels of oil are used to make plastic bottles as well as the additives infused into the plastic, such as plasticizers, biocides, and pigments. Making plastic bottles requires a factory with its associated greenhouse gas emissions, such as carbon dioxide.

Glass is made of four components, namely sand, soda ash, limestone (or boron oxide for borosilicate glass), aluminum oxide, and minor, natural additives depending on the type or design. These ingredients are quarried with the corresponding use of fossil fuel required to extract them. Making glass bottles also requires a lot of heat and this process generates carbon dioxide emissions.

Transporting glass bottles on a truck produces a heavier carbon footprint than transporting plastic bottles because glass weighs more. But transportation from factory to market is a small slice of the full lifecycle of a glass bottle. The added transportation impact is more than offset by the glass bottle’s long life and potential to be perpetually recycled.

Health Affects

Glass bottles are non-porous, eliminating any risk of harmful chemicals leaching into your (or worse, your growing childrens’) beverage. Glass bottles are also suitable for heat sterilization to eliminate bacteria.

Plastic bottles, being permeable, can affect the flavor and quality of their contents by absorbing tastes or smells. Plastic bottles also contain chemicals that can, over time, leech into the bottle’s contents.

BPA (bisphenol A) is often cited as a health risk of plastic but today it is not used in plastic that could have lengthy food contact. The U.S. FDA banned baby bottles from containing BPA years ago. Companies that make BPA-free bottles, and related items like container lids, are aware of BPA concerns and typically clearly state “no BPA” in the plastic product’s sales  copy.

While BPA might be less of a concern these days, chemicals known as phthalates (recall PET’s official name is polyethylene terephthalate) are a serious concern as they are proven to affect our health. Besides being a component of plastic bottles, phthalates can be found in many other products that are in direct contact with food.

PET will eventually degrade into microplastics and then pass into the food chain or on to us by other means (salt, air, more). If you are feeling especially nerdy you might want to peruse this scientific paper about the impact of microplastics on us and on marine animals. (It gets easier after the abstract.)

Recycling Glass and Plastic Bottles

PET is recyclable. However, most plastic bottles never make it to a recycling facility. This has caused one of the biggest problems our planet is facing today; our plastic waste has skyrocketed to a rate that’s almost impossible to grasp.

Glass bottles, on the other hand, can be recycled indefinitely. Many glass bottles and containers in your local market are made of recycled glass. According to the World Wildlife Fund, recycled glass decreases water pollution by 20% and air pollution 50% versus the first time it is made.

Cullet (crushed glass used for recycling) costs less than virgin glass and saves energy because it melts at a lower temperature and thereby reduces emissions of greenhouse gases. In fact, recycled glass uses 40% less energy the new glass. According to British Glass, recycling one glass bottle saves enough energy to run a desktop computer for 25 minutes.

Environmental Impact When Not Recycled

Plastic bottles are estimated to take several centuries to decompose. When plastics degrade in our oceans they turn into tiny particles called microplastics.

These microplastics are less than five millimeters long. They make their way into the stomachs of fishes and other marine species, moving through the entire food chain. While microplastics are confined to the gut, which we usually do not eat, that cannot be said about the chemical constituents of the microplastic, including toxic phthalates, which could end up in the tissue that we do eat.

Microplastics can already be found in almost every possible natural environment – the marine ecosystem, our water, salt, soil, food, everywhere – and microplastics are expected to persist for centuries.

Nurdles are a form of microplastic associated with plastic manufacturing, including plastic bottles. Unfortunately, due their small size, they are hard to contain at the factory and easily find their way into the environment. We get pollution from all phases of the plastic lifecycle from nurdles to fully made trash, to microplastics

Is Glass Biodegradable?

According to the New Hampshire Department of Environmental Services, glass takes one million years to decompose – indeed a very long time. However, a discarded glass bottle is likely to be damaged by environmental action and ground back into sand in much, much less than a million years. Be it 10 years or a million, while it’s awaiting that fate, glass does not leach toxins and other harmful chemicals into the environment.

Are glass bottles better than plastic?

When you consider the perpetual reusability and recyclability of glass and that it has no dangerous health or environmental impact it’s clear that glass is the better choice for food, health, and planet earth.