Plastic number 5 - Polypropylene

Polypropylene, plastic number 5, is one of the lowest hazard plastics around. You are familiar with it in ice-cream containers, drinking straws and the screw top lids of soft drink bottles.  It is also in most homes in the form of Tupperware and in rugs and carpet backings. Most domestic uses of PP are either for long term use, such as in food containers, or for food packaging, which is able to be recycled easily.  For these reasons there isn't a lot of concern about over use or misuse of PP.

Our fabulous Bokashi buckets are made of recycled PP, for example, and if you own one, will use it for many years to come.  But if lid were to split and need replacing, for example, it would be easily recycled with in the Council recycling.  This is really the ideal way to use plastic. Make sure it's for long term, not single use, and then recycle the plastic product when the useful life is over.

One use of PP that isn't so fabulous is the now ubiquitous 'green' shopping bags.   Becasue the PP in these bags looks more like a fabric bag than a plastic bag they are known as 'non-woven'.  Green bags are strong and really useful for grocery shopping.  I'd rather see a green bag than a plastic bag at the supermarket checkout any day.  But if they tear, as they sometimes do, they are just as likely to end up in landfill as a LDPE plastic bag, and they simply don't biodegrade.

There are other concerns with non-woven polypropylene  (NWPP).  Although less energy is used to create NWPP bags than it does to create cotton bags, they take more energy to manufacture than conventional plastic bags.  They need to be used many times for an environmental benefit to start to accrue - about 171 times. Sadly, many are used about half that number.

Some companies claim to be making NWPP bags from recycled material, however with current manufacturing techniques this is not possible and all NWPP bags are made from virgin material.  And although PP is very recyclable, the NWPP used in disposable nappies, surgical gear and shopping bags isn't. 

Studies have found they can become really contaminated with bacteria (meat, sweaty gym clothes - it all ends up in there) and they should be washed occasionally.  Unfortunately, as is the way with these things, many people will find that too much of a hassle and just replace them. NWPP bags are all made in China, so the carbon footprint, from crude oil as the raw material, to shipping across the globe, to ending up in landfill is not fabulous (the same can be argued for most re-useable shopping bags, but it's a particular problem here because they aren't being used over and over and many people have accumulated many more than they need).

We all need to carry our groceries in something, and there's almost always a degree of compromise in most eco-lifestyle choices.   As always, it's always better to have thought about it and made a mindful decision about what is going to work for you, rather than not thinking about it at all.