Thread by @GeorgeMonbiot

It's not just that many "compostable" bioplastics don't compost as they should. Most are likely to be more environmentally damaging than the fossil fuel plastics they replace.🧵

Favoured feedstocks for bioplastic are maize and potato starch. Both crops are notorious for the soil erosion they cause. They also require large applications of pesticides, fertilisers, irrigation water and diesel.

Then there's the land footprint: the environmental metric that's perhaps most important of all, but is all too often ignored. Maize and potatoes require good arable land. Every hectare used to make bioplastic is a hectare at least partly removed from food production.

This means that either bioplastic raises the price of food, pushing it further out of the reach of the poor, or it requires an expansion of the arable land area, with all the environmental damage that entails.

I say "likely to be", as remarkably little work has been done comparing the environmental impact of bio- vs fossil plastic. Why, I wonder?
This paper makes a good start. doi.org/10.1016/j.onee…

So which should we choose? Fossil plastic or bioplastic? Well, to the greatest extent possible, neither. The priority is to reduce the use of all materials, rather than spreading the fire of environmental destruction from one sector to another.

Thread triggered by this report, by @phoeb0
theguardian.com/environment/20…