The Journey of the Plastic Bottle

Ah yes, the ubiquitous plastic bottle. Despite the growing trend of reusable bottles, America is still in love with disposable, one time use plastic bottles. According to the International Bottled Water Association (IBWA), bottled water consumption in 2012 amounted to 9.67 billion gallons, just large than a 6% year over year increase. Bottled water is a multi-billion dollar industry—$11.8 billion in 2012. Why do people consume bottled water? Our nation is in constant motion; with so many people constantly on the run, perhaps bottled water is a convenience factor. The IBWA asserts that “[Consumers] know that safe, convenient, refreshing bottled water has zero calories and is the healthiest option on the shelf.” I’m no expert, but I would hope the general public is educated enough not to need to be informed by the bottled water industry that water is a healthy, zero calorie beverage. I would hope.

But no matter how they sell it, bottled water, along with the billion dollar market for carbonated beverages, it means one thing: they need a whole lot of plastic bottles. But how do you make a plastic bottle? Physically making the bottle is simple compared to the task of making the plastic itself. What even is plastic? Most plastics begin miles below the earth’s surface, in the form of viscous black liquid petroleum—crude oil.

But how is that black oil turned into a clear plastic bottle? Most plastic bottles are made out of polyethylene terephthalate (there’s a reason why they abbreviate it PETE). These bottles are lightweight and are imprinted with the recycling code “1.” The entire process requires many complicated steps, the technicalities of which will not be described in detail here. The concept is that plastics are polymers. “Poly” means many, and “mer” comes from the Greek merlos, meaning part. Thus, polymer means “many parts.” This is indeed the case. A polymer is essentially a chain of monomers (“one part”). One simple structure repeats itself in a seemingly endless chain. The repeating part of PETE is shown below.

In a (complicated) process called polymerization, these parts are linked together to form a long chain—the polymer.

But if only it were that simple. It turns out that crude oil can’t simply be processed directly into plastic. There are several other processes that must occur to transform crude oil into intermediate products that can then be used to make the plastic itself. After the plastic itself is made, it must be shaped into whatever shape specified by the beverage company. A common process for this is to first mold it into a test-tube shape with threads for a cap, called the preform (pictured at right). The walls of the preform are intentionally thicker than the walls of the finished bottle. This is because the preform is placed between two halves of another mold, and air is injected into it until it conforms to the shape of the mold. Essentially, the preform is inflated like a balloon until it reaches its final shape. Pretty cool, huh?

All in all, crude oil has to be drilled from a well and shipped from the well to a crude oil refinery. From there, intermediate products must be produced, and finally the plastic itself. After that, it still has to be formed into a bottle shape. All steps have potentially involved transportation of the finished or unfinished products to and from different facilities. And the bottle doesn’t even have water in it! The bottles still have to go to the beverage maker’s facility to be filled and then shipped to local distributers and stores.


The moral of the story? In the case of the plastic bottle, there’s more than meets the eye. So think twice before you choose bottled water over tap water.





  1. Its funny how people react when you tell them they are drinking out of containers made out of the same base resource that is used to synthesize the fuel that runs their SUV. Really informative blog. Can’t wait to see what you write next week.

  2. This was really interesting! The picture of the dark crude oil really makes you think about where your beverage bottles are coming from. I used to be an obnoxious user of plastic water bottles, but I’ve transitioned to a re-usable water bottle. This post really makes me happy I did!

  3. Sarah Bevilacqua says:

    You have a really good way of making borderline boring topics interesting. I knew the general idea of making plastic, but like Kyle, I really appreciated the picture of crude oil. It’s hard to imagine that a clear bottle comes from an ink black liquid. Also good pitch for the environment!

  4. The image of the crude oil (gross!) juxtaposed with the clear water bottle was really effective. I should have used that on my college roommate, who was (a pretty decent guy but) the most wasteful user of plastic water bottles I’ve ever met. In my experience, which is limited, of course, the wealthiest people I knew were usually the pickiest about always having bottled water. I don’t want to generalize, though; is that the case for others?

Speak Your Mind

Skip to toolbar