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  Straits Times Forum 25 May 07
Plastic bags needed, but reduce dependence
Letter from Liang Xinyi (Ms)
Communications Executive Singapore Environment Council

Straits Times Forum 16 May 07
Plastic bags are the enemy
Letter from Sam Bateman (Dr)
S. Rajaratnam School of International Studies
Nanyang Technological University

Straits Times 12 May 07
Plastic bags are not the enemy
By Senior Writer, Andy Ho

SOME supermarkets in Singapore have taken to asking you to 'donate' 10 cents for every plastic bag you use when shopping on the first Wednesday of every month. The aim is to get consumers to reduce the use of plastic bags due to their environmental impact.

However, the move is like a regressive tax that hurts the poor much more than the rich. More importantly, is it really necessary?

As the National Environment Agency (NEA) notes, 'plastic bags do not pose a threat to the environment in Singapore'. Still, it says, it is wasteful to use plastic bags excessively.

On average, Singaporeans use 625 bags per person per year. Research in several countries shows that the main problem with plastic bags is not their environmental impact per se but littering.

They are so light that plastic bags can easily become windblown litter. But littering is generally not a problem here. In countries where it is, discouraging their use might be justifiable.

For instance, in South Africa, its Environment Minister (only half in jest) called the plastic bag his country's national flower: It can be seen snagged on trees and hedgerows, fluttering along road fences and bushes, littering school yards, polluting rivers and so on.

The other morning, I drove up and down Mandai Road out in the suburbs and counted all of four stray plastic bags. In the afternoon, I counted just one in the Toa Payoh streets around The Straits Times office.

In most countries, despite being very visible, plastic bags represent just a tiny fraction of all the waste.

In Ireland, for example, they comprise under 1 per cent of total waste by weight and under 1 per cent of the bags become litter.

So littering may just be a perceived problem rather than a real one.

What about the fact that plastic bags choke up landfills since they are not biodegradable? Singapore has just one landfill left at Semakau island. This accepts only ash from the four incineration plants (at Ulu Pandan, Tuas, Senoko and Tuas South) as well as trash that cannot be incinerated, like construction and demolition waste.

Thus, plastic bags don't appear at Semakau anyway. Instead, they are incinerated just as 91 per cent of the 2.56 million tonnes of waste generated last year were. During incineration, energy is (re)captured as heat which is then used to boil water to produce steam which drives turbines to generate electricity.

According to the Environment and Water Resources Ministry, the four incineration plants consume about 20 per cent of the electricity they generate. The excess is sold to consumers through the electricity market, supplying 2 per cent of Singapore's total electricity consumption.

Thus, the petroleum used to make plastic bags is, in effect, reused to generate power.

If not plastic, then what? Making people pay for plastic bags - like Ireland's 'plastax' imposed to fight a perceived problem of littering - led to an increased use of paper bags, with more check-out staff resorting to double bagging - using two paper bags so they won't tear - and thus generating even more waste.

In fact, paper bags are environmentally less friendly than plastic bags if we compare them over their life cycles.

In such a cradle-to-grave analysis, we determine the energy consumption and environmental emissions at each stage of a bag's life cycle.

This approach starts with raw material extraction and proceeds through its processing, and then the manufacture, distribution, use, reuse and final disposal of the bag. The consumption of other base materials like ink, pigment or glue, energy sources (oil, gas, coal, and so on), and the way solid and waterborne waste as well as atmospheric emissions are managed must also be factored in.

Within this broader concept of sustainability, a German study and three Irish ones, among others, have found plastic better than paper bags. Fewer resources are used to make the former:

Over their lifetimes, a plastic bag uses about 40 per cent the amount of energy as one paper bag does. Also, transporting the lighter plastic bags around uses 11 times less fuel compared to paper bags. Having less mass than paper means that plastic bags produce less solid waste too.

All in all, factoring in consumer convenience as well, plastic bags do better than paper bags on all indicators except for the risk of littering.

A life-cycle analysis carried out in September 2004 by EuroCommerce, an organisation whose members include the national trade associations of 29 European countries as well as individual companies, confirmed that there was little or negative gain to be made if single-use paper bags were substituted for single-use plastic bags.

What's best then?

A 2004 study carried out by the Carrefour hypermarket chain in France found that plastic bags that were durable enough to withstand more than two trips were of particular benefit.

Two Australian studies (not funded by the plastics industry) as well as the EuroCommerce study confirmed this finding. So go with durable plastic bags.

What about reusable calico (cotton) bags? Cotton growing uses a lot of chemical fertilisers and pesticides. In fact, 10 and 25 per cent of the world's pesticides and insecticides, respectively, are used to grow cotton. Consider also the deplorable conditions under which Third World workers labour to make these bags.

Moreover, a life-cycle analysis must include the use of water, detergent and power to wash and dry such bags, waterborne waste thereby produced, and even electricity used to iron cotton bags, as some people are wont to do.

How about biodegradable bags? If these end up in landfill, they may degrade faster - but we have no such landfills anyway. No biodegradable polymer used to make these bags is less dense than polyethylene (used to make the usual plastic bag).

So, bag for bag, a biodegradable one requires more raw material to begin with.

Moreover, to speed up degradation, a chemical additive is included in the BioBag marketed in Australia by Valpak, for example. In sum, their overall resource and energy use as well as their greenhouse gas emissions over the whole life-cycles aren't too promising.

Of course, more could be done to encourage people to adopt the reusable plastic bag. Yes, the affluent could choose to blow US$960 (S$1,400) on a Hermes fold-up shopping bag.

The rest of us just need to be reminded not to litter with the plastic bag.


Straits Times 16 May 07
Plastic bags are the enemy
Letter from Sam Bateman (Dr)
S. Rajaratnam School of International Studies
Nanyang Technological University

DR ANDY Ho, in his article, 'Plastic bags are not the enemy' (ST, May 12), misses some key points.

The problem with plastic bags is not just littering but their impact on the marine environment and marine life.

It's an old environmental adage that 'everything has to go somewhere', and stormwater and run-off inevitably take many of the plastic bags used in Singapore to the sea where they can go on polluting and killing marine life for many years.

Aluminium cans and plastic bottles do not degrade in the ocean for over 200 years and common plastic shopping bags will also last a long time.

The durable plastic bags recommended by Dr Ho would be around in the sea longer.

The statement by the National Environmental Agency that 'plastic bags do not pose a threat to the environment in Singapore' reflects little sensitivity to the problems of the marine environment.

Plastic bags may not be a threat to Singapore's environment but they certainly are to the seas around Singapore.

I understand Singapore has measures in place to recycle stormwater and to prevent waste from entering the sea. However, Singapore is an island and it is physically impossible to prevent all waste from entering the sea.

Dr Ho talks about not finding many plastic bags along Mandai and Toa Payoh roads but I did my own field research at the weekend. I went to West Coast Park and checked the waterfront and nearby canals. I traced the canals back inland as far as I could and saw no measures to prevent waste from reaching the sea but there were plenty of drains into the canals, and no shortage of rubbish, including plastic bags, on the banks just waiting for the first heavy storm to carry it all to the sea.

The waterfront around West Coast Park was particularly depressing with rubbish, including a rubbish bin near the shore overflowing with waste in plastic bags. The waterfront around the Sungei Buloh wetlands was just as bad when I visited it some weeks ago.

I have two suggestions.

First, there should be no let-up with measures in Singapore to reduce the use of plastic bags and, second, some environmentally aware community group should promote a 'clean up Singapore waterfront' campaign.

The campaign would stop the waste that's on many parts of the foreshore from getting back into the sea.

Straits Times Forum 25 May 07
Plastic bags needed, but reduce dependence
Letter from Liang Xinyi (Ms)
Communications Executive Singapore Environment Council

I REFER to the article, 'Plastic bags are not the enemy' (ST, May 12), and would like to address some of the issues brought up.

Plastic bags are needed in our daily lives for various uses (from lining refuse bins to containing wet produce), but excessive usage and wastage of plastic bags, especially empty ones, has many environmental repercussions.

Plastic bags are produced from petroleum, a non-renewable fossil fuel. When burnt, plastic bags emit carbon dioxide and poisonous gases. They take approximately 1,000 years and 450 years to break down on land and in water respectively.

It is thus necessary to reduce our dependence on plastic bags in order to conserve fossil fuel reserves for future generations, as well as to curb carbon dioxide emission to mitigate the climate change phenomenon.

While it is true that plastic bags generally do not constitute an eyesore on Singapore's streets, we should be reminded that this is often thanks to the efforts of an efficient squadron of sweepers and cleaners.

A recent study by the National Environment Agency has concluded that littering still remains a perennial issue in Singapore, especially among the young.

Due to their light weight, plastic bags are easily blown around and often land up in waterways, rivers and the sea. It is easy to observe plastic bags stranded among the mangrove roots or floating in the sea at some of our major beaches and mangrove spots.

Local coastal clean-ups have revealed that plastic bags are one of the most common forms of coastal debris. Each year, millions of marine creatures and seabirds choke on plastic bags which are washed into or discarded in the waters.

Plastic bags are cheaply and readily available in Singapore, creating the impression that they are 'free'. However, if we include the environmental costs of plastic bags, pre- and post-production, the true costs reflect a staggering price to our environment.

It is noteworthy that both plastic and paper bags have their benefits and drawbacks. However, none would emerge the champion if its environmental impact is assessed over its life cycle. A reusable bag is still the best alternative in the long haul.

Ultimately, the decision to use plastic, paper or re-usable bags still lies with the consumer.

Everyone should be well informed of the environmental issues surrounding plastic bag usage and aware of the alternatives available before arriving at a responsible decision.

Let's move beyond plastic bags comments on this article and other thoughts on the leafmonkey blog

Related articles on marine litter, Global issues: marine, Singapore: plastic bags and wild shores
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