Wednesday 5 February 2020

What Does BPA, PLA, Phthalates Mean?

Some Plastic Terms Explained
Plastics Animals in a Row Image by Magda Ehlers from Pexels

What is BPA? 

BPA stands for Bisphenol A and used in resins since the 1950s and also used in plastics.

It can form a shiny hard plastic surface called polycarbonate and has been used in the production of plastic plates, microwaveable food trays, re-usable water bottles, sippy cups, canned foods, dental sealants & even some till receipts.

In a survey of 2,517 people 93% had detectable levels in their urine. It has been known to disrupt endocrine function affecting hormones in mice & has caused health concerns among many due to its estrogen mimicking effects. The FDA have since banned BPA in sippy cups and baby bottles. [BPA has also been banned in baby bottles in the EU.]


How to avoid? 

The advice mentioned in the National Geographic article above is to avoid putting plastics in the dishwasher (which may encourage BPA to leach out during the hot wash) and avoid plastics with recycling codes 3, 6 and 7 which could have BPA compounds. 

(Some BPA free alternatives are available but the article highlights that some of these can also be problematic – check out the article highlighted above for more info).


Phthalates are added to Poly vinyl chloride (PVC) plastic and helps to make it become more flexible. They can be used in paints, household cleaning bottles as well as vinyl floors. Due to its flexibility it can be used in cling film, catheters, IV tubes and children’s toys. Studies suggest it could affect hormones and also the fetus, so similar to BPA it can cause health concerns.


How to avoid? 

The website above suggests using wax wrap or parchment paper instead of cling film, avoid microwaving plastics and use ceramic or glass containers instead for storage. Buy cosmetics that are phthalate free. Plus avoid anything containing PVC.

Phthalates are commonly found in human urine samples. An analysis of 1999-2000 data found metabolites of DEP in all 2,540 samples and metabolites of DBP in 99% of samples. (DEP is a type of phthalate used in fragranced products, DBP can be found in nail polish). These 2 chemicals are now banned in cosmetics sold in the EU.


Double Rainbow Over Field Photo by James Wheeler from Pexels

What is PLA? 

PLA or Polylactic Acid is a plant based type of plastic usually made from cornstarch. Due to its natural backbone it is often touted as biodegradeable and sometimes compostable product. The downside it may need specific conditions to break it down effectively.

According to zerowasteman site they quote, ‘It is not recommended to put these PLA biodegradable plastics into your home compost, they might remain there for 100 – 1000 years.’


Industrial composters use a much higher heat setting, although it may not biodegrade at the same rate as your partially rotten food taken out for collection from the average household. Indeed, industrial composters may not accept any plastic based content whether natural or not. 

How to dispose? 

PLA bags are unsuitable for home composting and may also not be taken with your household food waste, so the natural solution is to recycle with normal plastic bags right? Sadly wrong! 

Recycle Now site states that plastic bag collections points at supermarkets cannot accept biodegradeable plastic bags. I’m guessing these bags are recycled into new bags, so they do not want biodegradeable content in it.

This can create a dilemma for the consumer – they want a non oil based plastic solution, one that breaks down as well, but at the moment it is not clear how best to dispose of them. 

Normal landfills may not have the right conditions to break them down quickly (as landfills are often hemetically sealed). Some household non recycling rubbish is sent directly to incinerators in energy recovery centres so the product may end up being incinerated at the end of its life instead.


Bioplastics is a term given to more natural, non petroleum based plastics. These may be derived from corn starch, sugar cane, vegetable matter, cellulose, wood chips or straw. I have seen mushroom based packaging also coming onto the scene using mycelium (they do say these are home compostable).

Wikipedia however states that,‘Not all bioplastics are biodegradable nor biodegrade more readily than commodity fossil-fuel derived plastics.’

They also state that the term ‘Bioplastic is misleading, because it suggests that any polymer derived from the biomass is environmentally friendly.' 


So similar to the PLA (polyactic acid, plant based plastic) above, some of these items may not be suitable for normal or even industrial composting.

Check out these sites for more: recycling biodegradeable coffee cups / how to dispose of your PLA based cup / how plastics are recycled (mentions compostable/biodegradeable).


It’s great that other plastic alternatives are out there but the consumer does need to be aware that it may not be as easy to dispose of, despite the impression by some of the products listing them as eco friendly or compostable. 

I think for the moment, re-use them as many times as you can, then put them in your normal bin and at least the basis of the product was less reliant on petroleum based chemicals.

Even better, try and switch to plastic free alternatives, for example re-usable tote bags, mesh bags for weighing and carrying vegetables, and covering foods with wax wraps, brown paper or tin foil, or buying bulk items in glass jars so there’s less need for plastic wrapping or bags.

Check out my reviews and homemade section for more ideas on making that plastic swap!

mobius loop recycling triangle symbolgreen dot symbol

Related articles – what the recycling codes mean

The article below looks at recycling symbols and numbers; also what HDPE, PET etc means and how these are recycled.