Blog about plastics, materials, processing and engineering tools

Bottles

Some time ago I wanted to buy a bottle for water and I decided to go for shopping, to simply buy a bottle. How surprised I was when I saw the number of available types. One made of polypropylene (PP) plastic, second of polycarbonate (PC) plastic, some had a label of BPA-FREE and so on. It was so confusing, that I decided to check what is going on…

Types of plastic bottles

Depending on the polymer being used we can have two types of permanent plastic bottles, one made of polypropylene and second of polycarbonate. The bottle, doesn’t matter of which material is made, is durable, reusable, it doesn’t wrinkle when exposed to the heat and can have colours, which kids just love.

And what about BPA-FREE?

bpa-free-id

Well, the BPA is Bisphenol A, a carbon-based synthetic compound, which is used to produce some plastics and epoxy resins.

And it is not the healthiest substance I know of. According to this study, the BPA can affect our health in a rather bad way.

Polycarbonate bottles

The polycarbonate (PC) is an example of a plastic that is usually produced using the BPA, but actually does not have to. It is possible to produce the PC without using the BPA. And that’s exactly what the BPA-FREE means: made without BPA. It also means that the plastic, whichever it is, does not contain the traces of BPA.

And polypropylene

The polypropylene is claimed to be safe for the health, even for newborn children and it is not produced using the BPA.Nonetheless, it’s better to check if the product based on the PP is also labelled BPA-FREE, especially if the product is used for food or water storage.

The point here is that, even if the PP is not produced using the BPA, it can still be produced in plant where other, BPA based resins are produced, and consequently the PP can be contaminated with the traces of BPA.

Three steps to buy a good plastic bottle:

1. Take the bottle out of package.

2. Check if one of the symbolsis presenton the bottom of the bottle:

a) “PC 07” or “PC 7” or the symbol:

PC07

b)  “PP 05” or “PP 5” or the symbol:PP05

3. Check if the bottle has the “BPA FREE” label*.

*Remember to buy only bottles with the label “BPA Free” stuck on the product or on the package of the product  (it cannot be abrochure). Here is an example of properly labelled product.

Sources and more informations:

1. BPA Free  information in Polish

2. Bisphenol A -Wikipedia

3. Study about Bisphenol A

4. Article – 1

5. Articale -2