Ever since plastic shopping bags were first developed, they have been controversial. At first, people were reluctant to give up their familiar paper bags. They resisted change. To modern observers, this conservative instinct may appear fortuitous. After all, aren’t plastic bags bad for the environment?

Ever since their introduction, the resistance against plastic bags was motivated in part by environmental concerns. Today, paper bags are being offered as alternatives to plastic by many retailers, and “eco-friendly” canvas bags are wicked trendy as the must-have accessory for the modern environmentally conscious shopper.

But there are reasons plastic won, and those reasons are not limited to price, convenience or hygiene. The environmental concerns about plastic shopping bags are not just wrong, but dramatically so. If you carry around an organic cotton bag for your shopping, you might as well nuke the planet for all the good you’re doing.

The first patent for a plastic shopping bag with gussetted sides, welded seams and intrinsic handles was issued in 1965. They weren’t introduced in America until 1979, however, and their uptake was slower there than elsewhere in the world.

Early plastic bags were weak and unable to cope with heavy items. A 1986 article in the LA Times describes the battle of the bags: shoppers with cars preferred the shape of paper bags; shoppers who walked or took the bus much preferred the more convenient plastic carrier bags.

Plastic packaging was displacing paper in supermarkets in large part for hygiene reasons. Liquids from meat would soak through paper, making it weak and exposing other items to bacterial contamination. Paper would stick to frozen foods and tear upon removal.

At the till, plastic bags were cheaper, lighter, stronger, easier to transport, easier to carry, and took up less space under the counter.

By the mid-Eighties, plastic bags were dominant, led by Europe, Japan and Australia, with the US not that far behind.

At least one country banned plastic bags at the outset: Italy. Its motive was to curtail litter. But elsewhere, the plastic bag came to represent all that was supposedly wrong with the modern world. They were made from petrochemicals. They were numerous. They were disposable. They persisted in the environment, and, as litter, had a visible impact on animal life. Today, plastic bags are the poster child for landfills, roadside litter and oceanic garbage.

In recent years, the most common argument in favour of the campaign against single-use plastic bags is not just about unsightly litter, but that “ocean debris” kills over a million sea birds and more than 100,000 marine mammals every year.

This claim, as I explained in a column two months ago, is highly dubious. Those numbers actually include injuries, and the sources cited in support of these numbers turn out not to support them at all.

They also do not place matters in the proper perspective. Campaigners like to use scary big numbers out of context, which is why they won’t mention the percentage of sea birds or marine animals that die. That number would be quite small, and unimpressive in a campaign advertisement. For the same reason, campaigners don’t point out that only between 2% to 3% of our plastic waste reaches the ocean as litter, and that the vast majority of oceanic garbage is in fact abandoned fishing gear, and not consumer litter.

Other arguments rely on simplistic rhetoric, like the notion that plastic persists in the environment, or contributes excessively to greenhouse gas emissions. These arguments are equally ill-founded, as we’ll soon see.

In response to popular fears about plastic bags, countries began to impose levies to discourage their use despite the paucity of evidence of substantial environmental harm. More recently, some cities, states and countries introduced outright bans.

The first plastic bag ban in the US was proposed in New York in 1988, but the idea was defeated in court by the plastics industry. A ban was enacted in the same year in Maine, but was overturned three years later.

In 2005, San Francisco introduced a levy on bags, valuing the “externalities” at 17 cents (about R2.50) per bag. This would, in principle, cover the cost of disposal, recycling and, where necessary, environmental clean-up. The fee was defeated soon after, but a ban on single-use plastic bags was enacted in 2007.

By 2008, major retailers in the US were engaged in voluntary initiatives to phase out single-use plastic bags. In 2014, California became the first US state to outlaw plastic bags, in a measure upheld by voters in 2016. A year later, in 2015, Arizona became the first US state to outlaw plastic bag bans, citing concerns that excessive regulation might stifle economic growth.

Meanwhile, other countries have followed suit, either imposing taxes on plastic shopping bags, like Denmark, Ireland and many other European countries, or imposing outright bans, as Australia and China did.

South Africa passed measures to prohibit light-weight bags and mandate a minimum thickness, and imposed its own charge of 46 cents per bag in 2003. This was intended to decrease their use and encourage the re-use of bags. A small part of that charge, three cents, rising to 12 cents today, was intended to fund a recycling programme.

Local retailers, too, have jumped on the bandwagon. Pick n Pay is piloting a compostable bag to replace single-use plastic carrier bags. Spar has launched a “Stop Plastic” campaign, complete with celebrity endorsements, and is offering alternatives to plastic bags in many of its stores. It even has a catchy hashtag, #ReThinkTheBag, so local Twitter celebs can signal their impeccable virtue.

Despite a significant initial fall in plastic bag use, research by Johane Dikgang et al. At UCT found that the effectiveness of South Africa’s plastic bag charge is diminishing over time, despite comprehensive application at checkout counters. Although the charge was reduced shortly after its imposition, it has returned to its initial level since. Still, the consumption of bags per R1,000 of groceries bought is steadily increasing. The study offers several good behavioural reasons why we might not be that price-sensitive to a low-cost, disposable item such as a shopping bag. Is saving 46 cents really worth shlepping a bunch of bags from home to the shops? Consumers also did not re-use bags for future shopping, as intended.

The charge has, however, turned a R400-million a year cost for retailers into a R400-million a year profit, a former chairman of the Plastics Federation of South Africa told a newspaper in 2006. A more recent estimate suggests plastic bags produce a profit to their sellers of over R700-million a year.

In addition, the tax man has collected some R1.8-billion since the introduction of the levy, of which half has been allocated to recycling projects, the government claims. The other half went into the general spending kitty, to enrich assorted Zumas and Guptas. Yet despite almost a billion rand in funding for recycling, government figures suggest that only 5% of plastic bags are in fact getting recycled.

The Dikgang study could find no data to evaluate the impact the bag charge had on the waste stream or the environment. There is simply no evidence, at all, that it works, and nobody is even trying to find out. However, in light of growing plastic bag use, the authors thought it reasonable to expect that the plastic litter problem will persist.

The recycling programme, outsourced to a a company called Buyisa-e-Bag, collapsed amidst allegations of fraud, and the R100-million it received from the bag levy went up in smoke.

The UCT researchers recommended that the levy be increased to achieve a sustained reduction in the consumption of plastic bags. If that is the goal you want to achieve, this makes intuitive sense, of course. However, the researchers were also pointedly sceptical of the goal.

“The plastic bag may be (and probably is) a symbol of uncaring abuse of the environment, without being intrinsically problematic,” the wrote.

“Indeed, plastic bags may impose fewer negative externalities than substitutes like paper bags. As such, one could argue that the marginal external cost should in fact be negative.”

Wait, instead of paying for plastic bags, we should be paid to use them because they’re better for the environment than alternatives like paper or canvas bags? Why hasn’t anyone told us this?

For answers, let’s turn to Denmark, the pioneer of plastic bag levies in Europe. In Denmark, only four single-use bags are used per capita per year, compared to 500 per year in the US and in South Africa. Their policy to curb plastic bag use has clearly worked.

Yet in February 2018, its Ministry of Environment and Food issued an astonishing report entitled Life cycle assessment of grocery carrier bags. It compared the environmental impacts, from resource extraction and manufacturing to end-of-life processing, of a range of plastic bag types, bleached and unbleached paper bags, re-usable organic and conventional cotton bags, and composite bags. It compared the environmental impacts of each against those of heavy-weight bags made from low-density poly-ethylene (LDPE), re-used as waste bin liners.

“In general,” said the report, “reusing the carrier bag as a waste bin bag is better than simply throwing away the bag in the residual waste and it is better than recycling.”

With that surprise out of the way, here are a few more. They will, I’m afraid, alarm you. You need to re-use a recycled shopping bag twice to reduce the environmental impact to the level of ordinary thick shopping bags made from virgin materials. For other plastics, you’d have to re-use the bag between 35 and 84 times to achieve the same low environmental impact.

Paper requires far more energy than plastic to produce, and is bulkier and heavier to transport. According to the Danish report, you’d have to use a paper shopping bag 43 times, no matter whether it’s bleached or unbleached, to reduce its environmental impact to that of ordinary plastic shopping bags.

If you have a composite tote bag made of jute, poly-propylene and cotton, you need to re-use it 870 times. If you prefer a nice pure cotton bag, you’d have to re-use it 7,100 times.

And if you’re a fancy-pants who insists organics will save the planet, you’d have to use your organic cotton shopping bag a mind-blowing 20,000 times to match the environmental performance of good old-fashioned plastic shopping bags.

To put that in perspective, that’s a shopping trip every single day, seven days a week, 365 days a year for 55 years to justify just one organic cotton bag. You’d need a daily shopping trip for 19 years to justify one ordinary cotton bag. It’s a trip every day for a month and a half to make your paper bags pay environmental dividends.

And if you re-use your plastic shopping bag even once, you’d have to take your flashy feel-good organic cotton bag to the market every day for 110 years to match the environmental friendliness of plastic. If you only went shopping three times a week, make that 250 years.

The Danish numbers are the most extreme I’ve ever seen, but that might be because Danes never litter and their waste management is super-duper amazing. Even so, other governments have also concluded that plastic bags are far more environmentally friendly than paper or cotton bags.

An impact assessment on proposed bag levy laws was conducted for the Scottish government in 2005. (Our government should take notes on how to compile an impact assessment.)

It concluded that a levy made little noticeable difference (1% or less) to environmental indicators. Waste increases with a switch from plastic to paper bags, unless a levy is also charged on paper bags. Paper bags have a higher environmental impact relative to plastic bags. Heavy-weight re-usable plastic bags are more sustainable than light-weight single-use plastic bags, paper bags, or degradable bags.

“A paper bag has a more adverse impact than a plastic bag for most of the environmental issues considered,” the report said.

“Areas where paper bags score particularly badly include water consumption, atmospheric acidification and eutrophication of water bodies.”

Environment UK issued a report in which it compared various bag types to light-weight bags made of high-density poly-ethylene (HDPE). These bags are less likely to be re-usable than the heavy-weight LDPE bags the Danes used as a reference, and which are mandated in South Africa.

It found that ordinary light-weight HDPE bags outperformed all other bags in eight out of nine environmental impact categories. This included the thicker and heavier LDPE bags, paper bags, HDPE bags with a pro-degradant additive, compostable starch-polyester bags, non-woven poly-propylene bags and cotton bags.

All of these had to be re-used, often many times, to match the low environmental impact of ordinary light-weight shopping bags. The worst of the lot, again, were cotton bags, which needed to be re-used 131 times to match single-use HDPE bags. If those HDPE bags get re-used at all, even if only for waste bin liners, that number rises sharply.

This result is much, much better for cotton bags than the Danish study, but it does not make them “eco-friendly”, by any stretch of the imagination.

Besides, even after only four and a half months of daily use, a cotton bag is going to be pretty grungy. Which brings us to the clincher: human health.

Research has found that people “seldom if ever” wash re-usable bags, and often re-use them for different purposes. Most kinds readily absorb meat juices and other liquids, and are often stored in warm cars, which makes them perfect petri dishes for bacterial contamination.

If you use a re-usable cotton shopping bag, you might not live long enough to realise its supposed environmental benefits, even under the best of circumstances.

The mandatory charge for plastic bags, the government levy, the voluntary plastic bag reduction programmes, and the campaigns to ban the plastic bag, are all terribly misguided. They’re making the world a worse place, for human health and the environment alike.

When the cashier at the till greets you with a smile and that warm word of supermarket welcome, “Plastic?”, just say: “Yes please, I’m saving the planet. I don’t want to get sick. And your boss is an idiot.”

Hurrah for the cheap, convenient, strong, hygienic, and amazingly eco-friendly plastic shopping bag! DM