I should go plastic-free.

Reducing plastic waste is an excellent idea, and so is avoiding single-use items like plastic bottles. But avoiding the stuff altogether? Green groups are worried that the war on plastic could do more harm than good, and I’ve already written about some of the problems with the alternatives to plastic. If you live in the UK and dispose of plastics properly, then it’s pretty unlikely to end up in the sea.

And why only plastic? All types of waste are bad for the environment. Currently, going ‘plastic-free’ is something of a national obsession, even though plastic makes up just a small fraction of waste in this country.

If you are concerned about the impact of plastic pollution, there would be more benefit to getting involved in beach cleans and litter picking than searching around for alternatives to plastic. So let’s carry our reusable bags and bottles with us and refuse the straw. But then let’s move on.

If I am good at recycling and use a bamboo toothbrush, it’s surely ok to fly. I should just pack some reusable cutlery for the flight.

Sadly, it takes more than separating the recycling to fly and still keep your environmental impact down. A a well-known study found that the benefits of recycling are quite small compared to the impacts of flying, which emits so much co2 and other nasties.

Depending on how far you flew, you’d basically have to spend the rest of the year growing all your own food, buying nothing new, and walking everywhere in order to make no more than your fair share of impact on the planet. (And for the record, taking a reusable bottle on a return transatlantic flight will save around 320g of greenhouse gases, the carbon footprint of the flights will be at least 1.6 tonnes).

I should bring my own containers to buy meat and cheese

Hmm……. a recent, highly-regarded meta study of the environmental impacts of food concluded that the single best thing you could do for the environment is to give up animal products altogether. Even the most sustainably produced meat has higher impacts than plant-based food. When you consider the huge environmental costs of meat production, avoiding the impacts of the packaging will make very little difference to that. And if you have to drive a bit further to reach a shop that will allow you to bring your own container, the added carbon emissions will probably reduce any environmental benefits to nil.

I should aim to buy things in ‘recyclable’ or ‘biodegradable’ packaging.

Not necessarily. Most of the environmental impacts of a product occur before it reaches the shop shelves, rather than what happens to it when we’ve finished with it. Many packaging materials that have a reputation for being more ‘recyclable’ (whatever that means) have a higher overall carbon footprint than packaging considered ‘less recyclable.’ Choosing what to buy according to what it’s made from is a headache, and it’s not even clear that there is any environmental gain from doing so. Even plastic can be recycled, whatever they tell you.

As for ‘biodegradable’ packaging, this really depends on how the materials to make the packaging are sourced, and whether it is able to fully decompose at the end of its life. If biodegradable materials end up in landfill, they give off greenhouse gases, and if biodegradable plastics are put in the recycling they can cause havoc. One recent study comparing the impacts of different types of plastic bottles found that the one made from plant-based, biodegradable materials ‘showed the worst environmental performance’ when compared to alternatives made from virgin or recycled plastic.

I should wear natural fabrics to avoid microfibres from polyester clothes getting into the sea.

I wish I knew of a solution to the problem of microfibres from clothes, but switching to ‘natural’* fabrics is not it. Materials like cotton have to be grown somewhere, and increasing land for agriculture is one of the major causes of biodiversity loss and deforestation. It also takes away land from food production, consumes lots of water, and emits greenhouse gases. A study found little difference between the overall environmental impacts of cotton, polyester, and hemp, and there is evidence that ‘natural’ fibres can also have impacts on wildlife. Hubbub have some suggestions for ways you can reduce microfibres shedding into the water.

You can tell whether a product is sustainable or not just by looking. If it is made from material x, it must be bad for the environment. If it is made from material y, is must be good.

Not necessarily. It depends how the item was produced, how the materials were sourced, how the product is used and how sustainable the alternatives would have been. Most of this information is not available to us when we are choosing what to buy.

For anything which is not food or hygiene products, it’s better to ask – how much do I need it and how much value am I likely to get from it? Do I need to buy it new, or could I get hold of it second-hand or borrow one?

Electric vehicles are an environmentally friendly alternative to petrol and diesel vehicles.

This depends what you mean by ‘environmentally friendly.’ Electric vehicles have less global warming impact, yes (although clearly it depends on the source of the electricity used to power them). But only when you compare them to conventional vehicles. Compared to walking and cycling, their global warming impact will be huge, because of the fossil fuels involved in mining and producing all the materials to make them, manufacturing them, transporting them, and generating electricity to power them in a system which still burns fossil fuels.

As well as global warming impacts, the process to manufacture electric vehicles is more toxic than the process to make conventional vehicles, the materials needed for them are hard to source ethically, and all vehicles add to congestion and local air pollution from tyres and braking.

So, electric vehicles do have some environmental benefits, but they are not ‘environmentally-friendly.’ The ideal is always to reduce car use as much as possible.

Plastic takes 1000 years to biodegrade.

No-one really knows how long it takes to biodegrade – it hasn’t been around for long enough. It could be centuries, it could be millennia, or it may not biodegrade at all. But it doesn’t biodegrade quickly, that’s for sure.

Imported food always has a higher carbon footprint than locally-produced food.

Not necessarily. If food is transported by ship it could potentially have a low carbon footprint, while local food that is intensively produced could have a high one. As a general rule, say no to foods (and flowers) that have travelled a long distance and have a short shelf-life. These are most likely to have been air-freighted, and were probably frozen or chilled along the way. Sadly, this includes avocados.

Prioritising which environmental issues to be concerned with is simply a matter of personal preference.

Well, yes and no. If you choose to be an environmental activist then yes, it is difficult to take on all the environmental problems in the world. You’re going to have to select. But when it comes to lifestyle choices, there is plenty of scientific research to tell us which are the biggest impacts to prioritise.

The biggest one thing you can do for the environment is to reduce your consumption of animal products. That’s not a value judgement of anyone’s personal choices. That’s the conclusion of a super-thorough, scientific study based on 40,000 farms across the world and covering 90% of all foods eaten.

Impacts can be measured and compared. Avoiding food waste has more benefits than avoiding packaging waste. The environmental impact of the way something is produced is usually more significant than whether or not it can be recycled. Avoiding flying will have more environmental benefit than reducing your rubbish.

Of course, whether or not you choose to eat meat or fly is a personal decision, and for some people, circumstances mean that the ideal option is not always possible. But if you are taking action to benefit the environment, aim to make choices based on the evidence.

Update:

Since I wrote this, everyone’s been asking, ‘in that case, what am I supposed to do?’ I wrote What to buy, and what not to buy and The Lazy Individual’s Guide to Reducing Your Environmental Impact, if that helps.

*I am not sure what is ‘natural’ about cotton compared to polyester. Cotton is cultivated by people for profit and most likely grown with modern irrigation technologies and synthetic pesticides. Polyester is derived from oil, a naturally occurring substance in the earth’s surface. Both oil and cotton have to be intensively processed before they can be turned into useful products. ‘Natural’ is not a very useful word in this context.