The
question we get asked most often is “are your bags biodegradable?”.
You would think there would be a simple answer to this question, but
the answer is more complicated than most people imagine. For
example, the location where something degrades can
determine what it turns into. Our bags are oxo-degradable, which
means that above ground, in the presence of oxygen and sunlight they
degrade to carbon dioxide and water at a similar rate to
cornstarch bags. However, we have chosen to use oxo-degradable bags,
not because of how they degrade above ground, but how they behave
below ground. Because the reality
is that the vast
majority of dog poo bags end up in landfill. And
in offering a product, we believe our responsibility extends beyond
the point of our bags being placed in a rubbish bin. This is where
things become more complicated. Because
when you place biological material in a landfill, it can be very bad
for the Planet.
Our
bags are made from HDPE (high density polyethylene) which is the same
material used to make “single use plastic
supermarket
bags”. There
has been a lot of talk recently about "single use plastic
supermarket bags", however, with very few people willing to
defend their use, the dialogue has been somewhat one-sided. Since our
bags are made of the same material (as are most dog poo bags sold in
New Zealand) we believe it might be a good time to offer some
perspective on the issue. Here's how we see it:
Every
human alive has an effect on our Planet, and we each have a
responsibility to keep our individual environmental footprint as
small as possible. This is made more difficult when we do not have
access to accurate information about how to do this. In the
developing world, there is a very real problem with plastic
pollution, but in the developed world, our contribution to
environmental pollution comes almost entirely from our greenhouse
gas emissions. It is critical that we understand the difference.
Special
interest groups within the environmental movement have decided they
need a rallying point and have chosen “single use plastic bags”.
We believe in doing this, have taken the focus away from some very
simple, unglamorous, and yet, very important things that we in New Zealand could be
doing to help save our Planet from the greatest threat we have ever
faced. That threat is Global Warming.
There
are many half-truths and dubious statistics circulating on the
internet about “single use plastic bags”. We believe that in
order to have a rational discussion on the topic, some of these need
to be clarified.
Misconceptions
about plastic bags:
"Plastic
bags clog up landfills"
Modern
landfills do have a problem. A massive problem. They produce
greenhouse gas. Lots of it. Globally landfills are responsible for
around 11% of all man made methane emissions (New Zealand's total annual landfill methane contribution is almost 4,000,000 tons CO2e). And methane is a very
potent greenhouse gas. Its warming potential is around 30 times that
of CO2. Methane is created by the anaerobic (without oxygen)
breakdown of biological materials in landfill waste. Biological
material consists of things like wood, paper, garden waste and food
scraps. It constitutes a staggering 64% of our domestic waste. It is
this biodegradable material that is causing the problem, not the
inert waste. If the food scraps you scrape into your rubbish bin
produce 4kg of CO2 above ground, in the landfill, the methane
produced has an equivalent warming potential of 120kg of CO2e.
Ironically,
HDPE bags can prevent the production of greenhouse gases in landfills
by preventing water (essential for anaerobic degradation) from
getting to the biological material. So biodegradable material,
secured tightly in a plastic bag can not only be prevented from
turning into methane, its carbon content can be trapped in the
landfill forever, taking it out of the carbon cycle. This is known as
carbon sequestration. You will be hearing a lot more about carbon
sequestration over the next few years because we have already pumped
too much carbon in the atmosphere, and we need to find ways to reduce
it by taking carbon out of the carbon cycle. When you landfill an
HDPE bag containing biodegradable material, the plastic that came
from crude oil pumped up from underground, is returned underground
and takes with it, yet more carbon. (that's if you decide you don't
want to recycle)
"You
can't recycle soft plastics"
Actually,
you can. The problem is that it currently takes a little more effort
than recycling your hard plastic, because it is not currently
collected from your door so you have to take it back to the
supermarket where you bought it. And if you do collect all your soft
plastics (from frozen pea packets to biscuit wrappers, and everything
in between), you will notice that the plastic bag you put them in
accounts for a tiny fraction of the total volume of the soft plastics
you have collected. And you will find you have collected a lot of
soft plastic.
"Plastic
bags are made of toxic chemicals"
There
are many types of plastic, but when we discuss them we seldom
differentiate between them. Some plastics are toxic, some are not.
PVC, polystyrene and polycarbonates are three examples of the former.
They contain aromatic hydrocarbons which are dangerous to humans.
Single
use plastic bags are made of HDPE. This is a very pure compound made
up of just carbon and hydrogen in a linear chain. It is not toxic.
Its basic building block is ethylene (this occurs naturally in
plants). To produce HDPE, ethylene is formed into long chains, which
are very stable. HDPE can be burned. This produces carbon dioxide and
water.
"Every
piece of plastic ever made is still with us"
This
well-worn phrase is not actually true. Plastics eventually degrade to
smaller molecules (mostly carbon dioxide and water). Their speed of
degradation is dependent mainly upon the wall thickness of the product they are made into.
"Plastic
bags take a hundred years to degrade"
Thin
film HDPE is an engineering miracle. With a wall thickness of less
than the width of a human hair, an HDPE bag can easily hold one and a
half thousand times its own weight. Pound for pound this makes them
an incredibly efficient product. The long carbon chains in HDPE not
only make it very strong for its weight, they also make it hard to
break down. Having said this, there are organisms in the environment,
both bacteria and fungi, that can metabolise it. It is not dissimilar
in its chemical composition to bees wax. Modern production of HDPE
uses additives that form weak points in the carbon chains, that react
with sunlight to break the chains down into much shorter lengths.
So, above ground (in the presence of UV light), it begins to degrade
quite rapidly. This is helped by the fact it is a thin film (around
13 microns in thickness). The smaller the pieces become, the easier
it is for microbes to digest them. It can't get into our food chain,
because if ingested by an animal, it can't pass from the animal's gut
to its tissue. When degradation is complete (called mineralisation),
the two chemicals you end up with are CO2 and water.
"Huge
numbers of plastic bags end up in the environment and cause
pollution"
Many
countries, especially in third world, have poor or non-existent waste
management systems. A recent scientific study has concluded that 95%
of all oceanic pollution originates from 10 large rivers of the
developing world. This does not mitigate our responsibility, but It
does make it possible to calculate New Zealand’s contribution to
oceanic pollution. Although we are led to believe that our use
of “single use plastic supermarket bags” is a large contributor to global
oceanic pollution, the facts do not bear this out. New Zealand is a
first world country and does a very good job of ensuring the vast
majority of our domestic waste ends up in landfills. And, of the
small amount of litter that gets into our environment, “single use
plastic bags" make up just 1%. Interestingly, 40% of our
environmental litter is fast food wrappers. It is not absurd to infer
that most plastic bags that make it into our environment come from
fast food outlets. Which is not a particularly convincing reason to
ban supermarket bags.
"Plastic
bags kill marine animals"
If
you Google search pictures of The Great Pacific Garbage Patch you
will find a striking absence of plastic bags. What you will find are
a lot of bottles, and bottle caps. All the studies we have read
regarding deaths of marine animals by ingestion, blame hard plastics.
Plastic degradation is slower in the ocean due to lower temperatures,
but relative to thicker plastic, thin walled plastic bags degrade
much more quickly. HDPE has a specific gravity is around 0.95, so it
floats on or near the surface where it is exposed to sunlight (see
above).
Plastic
bags are not known to kill marine animals by entanglement. Here is a
quote attributed to David Santillo, a senior biologist with
Greenpeace, to The Times of London, "It's very unlikely that
many animals are killed by plastic bags. The evidence shows just the
opposite. We are not going to solve the problem of waste by focusing
on plastic bags. With larger mammals it's fishing gear that's the big
problem. On a global basis plastic bags aren't an issue."
There
is documented evidence that pieces of soft plastic have been ingested
by sea turtles.
Their known preference is for rubber balloons and clear/translucent
plastics such as cling wrap. Studies of our coastline have
determined that the known death rate of sea turtles in New Zealand by
ingestion of plastic, is two animals per year. However, the
information available does not, unfortunately, specify whether these
deaths are due to hard or soft plastic. However,
comprehensive
international studies show that the majority of turtle deaths caused
by plastic ingestion are due to hard plastic. The same is true for
sea birds.
If
even one sea turtle was killed by ingesting a plastic bag it would be
tragic. However, the threat of extinction seems much more likely
from other causes. The fishing industry kills hundreds of thousands
of turtles annually in gill nets and on long lines. People still
hunt them for their meat, eggs and shell (for jewelry). Human
population growth is encroaching on their breeding grounds, and
global sea level rise is eroding their nesting beaches.
(Interestingly, unlike most vertebrates, sea turtles do not have sex
chromosomes. The sex of their young is determined by the temperature
of the sand in which they lay their eggs. A few degrees temperature
rise could mean no males are born to continue the species. So a
pressing issue in their preservation is control of Global Warming).
"Single
use plastic bags are still a massive environmental problem. We use a
billion a year"
Recent
landfill statistics give us a very accurate picture of what we are
consuming by measuring what we are throwing away. So what percentage
of landfill is taken up with plastic bags? Plastic waste account for
12.1% of landfill. Roughly half of this (6%) is soft plastic.
"Single use plastic bags", however, are just a small
fraction of this total. There is an often quoted figure of one
billion bags used by Kiwis every year. This may be a little on the
high side, but if we use this figure, we can determine the percentage
of landfill taken up with single use plastic bags. The average
supermarket bag weighs around 5.5 grams (we will call it 6 grams).
1,000,000,000 x 6 grams = 6,000,000,000 grams = 6,000,000 kg = 6,000
tons. Six thousand tons of plastic sounds like a huge quantity but,
to our shame, we currently send to landfill around 3 million tons of
waste annually so, as a percentage, single use plastic bags make up
approximately 0.2% of this total. Less than one quarter of one
percent.
"There
are better options than plastic bags, like paper, jute and cotton"
From
a Global Warming perspective, this is not true. Paper production is
highly polluting. Paper cannot be infinitely recycled (a maximum of
4 times until the fibres become too short to bind to each other).
Eventually, unless it is burnt, all paper will end up in a landfill
where it will produce methane. Similarly when cornstarch bags end
up in a landfill, which the vast majority of them will, they create
methane. Plus any organic matter they contain will then be exposed to
water and will also turn into methane. Jute has a high water
requirement which limits its production. It also turns to methane in
landfill. A cotton tote bag with an equivalent carrying capacity has
a Global Warming Potential of 327 “single use plastic bags” (you
can find more information on this further down the page)
"When
you put plastic in a land fill it takes a thousand years to break
down"
Below
ground, deprived of oxygen, HDPE is inert. Similarly, if you send
concrete to the landfill, it will remain there, inert. It is strange
that a different standard is placed on these two substances. Both
have been extracted from the ground, chemically modified and returned
to the ground. The main difference is that the lump of concrete will
still be a lump of concrete in a billion years. (The plastic bag and
its contents may quite possibly have turned back into crude oil).
In
truth, if you put anything
in a landfill, you want it to remain there, inert and unchanging.
Burying
things is not a new practice for humans. If you dig down in the
centre of London, you will find evidence of Roman habitation 40 feet
below ground. Everything above that was deposited by humans. The
argument that HDPE is bad because it is a man-made substance must
also be applied to concrete; used by the Romans in ancient London
(though
invented much earlier than that *). As
far as we are aware, there is no environmental group advocating a ban
on dumping of concrete in landfills.
"Plastics
are a petroleum product so they contribute to Global Warming"
When
petroleum products are burned, their carbon content is dispersed into
the atmosphere as CO2. When crude oil is turned into plastic the
carbon is trapped. If the plastic is burned, its carbon content is
released into the atmosphere, but if it is buried, the carbon remains
trapped.
Incidentally,
if you have ever got close to a jar of crude oil you will know that
it is pretty disgusting stuff, for something made by nature. The
hydrogen sulfide it gives off, which smells like rotten eggs, can
actually kill you. It’s lucky that most of it is buried deep
underground. If it was possible to turn all of it into inert plastic
and re-bury it underground the world would, arguably, be a better
place.
"I
don't care what arguments you put forward, plastic bags are just
evil"
“Single
use plastic supermarket bags” are a tiny subset of all the plastic
we use. So, why do we all share a bias against them. We all like to
believe that we reason with our frontal lobes, but every decision
must pass by our amygdala, the part of our brain that registers fear
and disgust. Through many years of subtle indoctrination, “single
use plastic bags” have become somehow the embodiment of the
disgusting way we treat our planet. When you think about plastic bags
you may well think of stinking landfills, or dying sea turtles. But
“single use plastic bags" haven’t just fallen into this
role. Decades of visual imagery has seared into our brains an
association with death and decay and profligate waste. Even the term
"single use" is a misnomer, because almost all are used at
least twice. But whenever they are discussed in the media, they are
never thoughtfully re-purposed, they are "discarded". Next
time you see a news article about oceanic pollution, no matter what
kind, it will almost certainly be accompanied by a picture of a
“single use plastic bag”.
We
could quite easily have chosen “single use plastic drink bottles”
instead. What is the difference between them? One answer could be
that “single use plastic bags” have no strong pro-lobby group.
“Single use plastic drink bottles”, as a sub-group, is far more
detrimental to the planet than “single use plastic bags”. Their
wall thickness is around 50 times that of HDPE film which means they
remain intact in the environment far longer. They can be found in
their millions in the Great Pacific Garbage Patch and on the shores
of Midway Island at its centre, and their bottle caps in the stomach
contents of the resident dead albatross chicks. So, why is it these
more worthy candidates haven’t come to symbolise our profligate
Western lifestyles. One reason is that they have a strong pro-lobby
in drinks manufacturers, who constantly bombard us with advertising
images associating drinking from them as a joyful, beautiful,
life-affirming act. Just as with “single use plastic bags”, its
all in the marketing. If you think about it, in the developed world
at least, “single use plastic bottles” are completely
unnecessary. Everyone in New Zealand has ready access to clean
drinking water. Would banning “single use plastic bottles put such
a crimp on our decadent western lifestyles? If it was a choice of
banning one or the other, perhaps we should keep the one that
actually performs a useful function. Of course, it is not as simple
as making a choice between banning one thing or another. Every choice
we make affects our planet.
"Wait,
I am so confused. So what can I do to help save the planet?"
A
few simple things could really help. Here are 4 you could start with:
Stop
buying stuff you don't need. (Clothes, as an example - textiles
make up around 4% of landfill waste).
Stop
buying bottled water, or anything else that comes in a single use
plastic bottle. Just
Google a picture of Midway Island and you will see just how long they
can last in the environment. If you want to get really depressed,
look at the pictures of the dead albatross chicks and see how many
bottle caps you can count.
Most
importantly, buy a green waste bin and use it for everything
compostable that leaves your home.
If
you don't live in an area where council offer a green waste
collection service, find a private one. Not only will you be reducing
your harmful greenhouse gas emissions (around 14 tons per household
per year), you will be helping to more than double the useful life of
you local landfill. By the way, the reason it is not possible to
build houses on a landfill immediately after decommissioning it, is
less about what it seeping out of the bottom of it than what is
seeping out of the top. Methane continues to gas-off for decades.
Separate
your soft plastics and take them back to the supermarket (you go
there every week anyway).
You
could collect them in a jute bag (although a plastic bag is more
convenient). This may remind you to take the jute bag with you next
time, so you don't have to buy another one, which will possibly end
up in the kitchen drawer with all your other jute bags.
By the way, even jute bags have an environmental footprint,
both in their production and disposal. And they cannot be recycled.
And, without wishing to sound alarmist, you might be interested to do
some further reading on a scientific study undertaken in San
Francisco after their ban on single use plastic bags, which
postulated that an average annual increase in deaths by bacterial
infection of 5.5 people per year was attributable to the increased
use of reusable grocery bags. (Another study found out why they might
be a problem - ninety percent of them never get washed.)
Better
still, use an HDPE bag. Then use it again. And again (except the one
you used to carry raw chicken). You can probably easily get 10 trips
to the supermarket out of it, provided you don't buy a lot of fresh
pineapple.
And
when it is past its useful life, either recycle it or give it a
decent burial. For example, if you have to put biodegradable material
in the rubbish (meat scraps or cat litter for example) then ensure you wrap them
tightly in an HDPE bag. And remember to tie a knot in the end off the
bag.
Then
…
Spread
the word to your friends and family. Tell them what you are doing
and why, and remind them that you are doing it for their children and
grandchildren.
"But
I would like to do more"
Great.
Start a community group. Push for your local council to supply
optional green waste bins to all households. If you want to get
militant, insist that these green waste bins be compulsory for every
household. Once you have achieved that, think nationally. Start
writing letters to your local MP. Get the rest of your group to do
the same. Together, with small steps, we can make a huge difference. Here is an example:
eugenie.sage@parliament.govt.nz
Dear
Eugenie
I
have learned that in New Zealand we are presently sending massive
quantities of biodegradable material to landfills in the form of
domestic green waste and kitchen scraps. Magnified by its conversion
to methane, this is a significant contributor to Global Warming.
I
would like you to consider a law making it compulsory for all
Councils to supply separate green waste bins to every domestic
dwelling in New Zealand.
Yours
sincerely
"Why
is there so much misinformation on the internet? How can I get the
truth?"
Arm
yourself with a little knowledge. Saving the planet is not rocket
science, but it is science.
Google
searches rank by popularity, not plausibility. Think about the
wording of your search choices. If you type in “911 was a
conspiracy”, then conspiracy is what you will get. Check every
source. Verify facts. On matters of science, look for well known
organisations, who publish peer reviewed studies. And please think
before you “like” or “share”. The uncritical repetition of
improbable facts makes us all more ignorant. The current plastic bag
debate is a good example.
Ask,
does this group have an agenda? For example, the information you are
currently reading comes from a site that sells plastic bags. Why
should you trust what is said here?**
Companies wanting to sell you stuff, and even some
environmentalists pushing a particular agenda, can bend the truth.
(see the TED talk at the very bottom of this page)
And
it is possible to lie by omission. Retailers who tout cornstarch or
paper waste bags as an alternative to HDPE, tell you they are better
for the environment. However, they neglect to mention that, unless
you compost these bags yourself, they will almost certainly end up in
a landfill, where they will produce methane, which is incredibly bad
for the environment.
**
An explanation as to why you might be able to trust what is being
said here (though we strongly recommend you conduct your own
independent research) is that we sell dog waste bags, so until the
general public can be convinced to pick up dog poo with their bare
hands, dog poo bags will be exempt from any proposed ban. However,
if all “single use plastic supermarket bags” were banned or
taxed, we would stand to gain financially, because a lot of people
currently reuse their supermarket bags to pick up poo. So why are we
defending supermarket bags? Because fixing problems requires us to
base our reasoning on facts. Banning these bags is illogical and will
create more problems than it solves ***.
And
it is sucking valuable oxygen away from what we should be should be
concentrating on.
We
need to fix our attention squarely on global temperature rise. This
is the thing melting the polar ice caps, that will flood heavily
populated low lying areas of the planet, causing refugee crises,
famine and war; the thing that will cause the extermination of
species by the hundreds of thousands. A global temperature rise of
just a few degrees.
If
we can convince every consumer of the planet's resources to start
doing these small, unglamorous things, together we can achieve
something huge. But if we expect New Zealand to become carbon
neutral, every New Zealand household must be working towards that
same goal.
***
One of the problems with changing the equilibrium of any
environment, is the law of unintended consequences. As an
example, it was once considered a brilliant idea to introduce the
Australian Possum to New Zealand so that it could employ people in
the fur trade. The result has been the devastation of our
native flora and fauna.
Consequences
can be equally catastrophic when you ban something. The example
in San Francisco of an increase in death rates from bacterial
infections coinciding with the banning of plastic bags, if connected,
would be a tragic illustration of this.
But
even the more mundane consequences of banning plastic bag are not
talked about. People must have an alternative, and every
alternative has an environmental cost. A non-woven multi-use
polypropylene bag weighs 80 grams, an HDPE bag weighs 6 grams.
So, if you can get 10 trips from an HDPE bag, you need to get well
over 100 trips from a polyprop bag. So if you don't get more
than 2 years out of your polyprop bag (assuming approximately one
supermarket trip a week), then from an environmental standpoint, you
are no better off than if you had been using HDPE bags. But in
the meantime, people would still be buying bags for bin liners, dog
poo pick up, and everything else that they currently re-purpose their
HDPE bags for. So the net result could well be more plastic,
not less.
And
if you have ever thrown away a multi-use bag because you somehow
ended up with too many, rest assured that you are almost certainly
not alone. And if it is just now dawning on you that it was
made of jute, and you put it in your rubbish bin, so it went to the
landfill, where it decomposed anaerobically, which produced methane
with a global warming potential of 30
jute bags,
then please congratulate yourself, you have obviously been paying
attention.
Concrete
and other problems
We
have included a couple of interesting facts about concrete to help
illustrate the point that in environmentalism things aren't always
quite as straightforward as they might be portrayed to be. Plus, it
might make you think twice about ripping up and re-concreting your
driveway just because it is looking a bit shabby.
Concrete
was first used by humans around 6,500 years ago. Modern production of
cement creates a lot of carbon dioxide, up to 1 ton of CO2 for every
1 ton of cement produced. Cement production accounts for
approximately 7% of world-wide greenhouse gas emissions.
Hydroelectric
power generation is thought of as green energy. However, hydro
schemes require dams, which are made of concrete. The Clyde Dam
contains 1,000,000 tons of concrete. If you calculate the embodied
energy of the cement required to build the dam, it comes to around 6
hundred million megajoules. The power output of the Clyde power
station is 7.5 million megajoules per year. So it will take 79 years
for this power station to cancel out the embodied energy required to
make it. The Clyde started producing power in 1993, so it should have
that debt paid off by 2072. If it is still running by then, it will
truly be producing green energy.
There
are ways to make concrete more environmentally friendly. One way is
to add fly ash. The addition of fly ash can reduce the CO2 producing
ingredients of cement by up to 90%. Ironically, the main source of
fly ash is coal fired power stations.
PAPER,
CORNSTARCH, JUTE AND COTTON Bags - some inconvenient truths
Paper
bags are often marketed as being greener than plastic bags. Paper, it
turns out, is a dirty business. We recommend that you do your own
research. Here are a few categories you could select in order to make
up your own mind. Just Google paper production and:
deforestation,
air pollution, water pollution, water consumption, landfill methane,
carbon monoxide, ammonia, nitrogen oxide, mercury, nitrates, benzene,
volatile organic compounds, bleaching.
Much
of the paper associated with food wrapping becomes contaminated to
the point where you would not put it in your recycle bin. But even
uncontaminated paper cannot be infinitely recycled (a maximum of 4
times until the fibres become too short to bind to each other). So,
eventually , unless it is burnt, all paper will end up in a landfill
where it will, as we all know, produce methane.
And
paper with printing on it, has additional problems. Google: recycled
paper and de-inking.
There
are five main problems associated with the use of cornstarch bags.
Firstly, their production takes valuable farm land away from food
cultivation. Secondly, they don't break down as quickly as promised.
This can be especially troublesome when they are labelled
“Flushable”. Thirdly they contaminate plastic recycling. Being
visually indistinguishable from petroleum based plastics, they are
unable to be sorted from the waste stream. This a serious problem for
those involved in recycling standard soft plastics. Fourthly, if bags are labeled biodegradable, people tend to be less careful in their disposal. Since cornstarch only degrades readily in industrial composting where the temperature are much higher than you find in the general environment, when disposed of carelessly, these bags can last as long in the environment as HDPE bags. But the fifth
and major problem they have is that if they end up in a landfill,
which the vast majority of them will, they create methane. Plus any
organic matter they contain will then be exposed to water and will
also turn into methane.
Jute
is hailed by many environmentalists as a saviour of the planet. More
than 95 percent of the World's jute production occurs on the Ganges
Delta, which sprawls across India's West Bengal and a large part of
Bangladesh. If you know anything about Bangladesh, you will be aware
that it is blessed with inordinate quantities of water (often way too
much of it). Everything we grow has a water requirement. Potatoes,
for example, have a water requirement of 287 M3/ton (cubic metres per
metric ton). While not as thirsty as cotton, jute requires a large
amount of water for its production (2,605 M3/ton). That is slightly
more than the quantity of water in an olympic size swimming pool.
Approximately ten percent of this figure is grey water component, or
water that is required to process to final product and is
contaminated in this manufacturing process. With water becoming a
scarce commodity in many parts of the world, it does not seem that
there are many places where an up-scaling of jute production would be
feasible. In case you are wondering, HDPE bags do not use any
appreciable water in their manufacture. If a jute bag weighs 100gm
then it took approximately 260 litres of water to produce the
material it is made from (this does not take into account any further
processing or dying that may have occurred).
If you want to dispose of your worn out jute bag responsibly, please
do not put it in your household rubbish. The safest thing you could
do is burn it. That way, hopefully, all you will be releasing into
the atmosphere is CO2 (provided it has no inorganic printing on it).
A
comprehensive study commissioned in 2006 by the UK Government
determined that a cotton bag has the same Global Warming Potential as
327 "single use" plastic bags, so would need to be reused a
staggering 327 times to equal the environmental impact of using a
new "single use" HDPE bag for each shopping trip.
This number is so large, it may not make sense to you. So let
us put it another way. Say you use your cotton bag for your
once-a-week supermarket shop. In order for it to have a less
detrimental impact on the Planet than using a brand new "single
use" plastic bag every time you shop, you will have to use it for 6 years
and three months. Let's say you decided you could squeeze two
uses out of your "single use" plastic bag before you turn
it into a bin liner. Then, in order to match that, your cotton
bag would have to last 12 years and 4 months. Three uses, 18
years 6 months. Four uses, 24 years 8 months etc.
Provided you burn it once it has worn out.
Everything
we do has a cost.
Carbon
sequestration
You
will be hearing a lot more about this in the near future, because our
future will depend upon it. Some “eco-friendly” sellers
already boast that their green products sequester carbon. Just as an
example, some who sell jute bags and other jute products, claim that
the jute takes carbon out of the atmosphere. While this is true when
the plant is growing, there is just one problem with this argument.
When any biodegradable material is disposed of, the carbon is
released again, sometimes as CO2 and sometimes as Methane. If you are
trying to reduce total atmospheric carbon, you need to make sure that
once sequestered, it cannot escape back into the atmosphere. This is,
in practice, impossible with an organic product. Unless you
bury it underground sealed in a container that is impervious to water
(like an HDPE bag, for example).
Environmentalism
We
may have mentioned before that we are passionate about the
environment. However, we find ourselves increasingly frustrated by
elements of the Environmental Movement. Here is an example.
Rogue
Scientists
Environmentalists
can struggle to achieve cut-through in this information-soaked modern
world. Sometimes, in order to grab attention, they massage statistics
and fudge facts. But when they put on a lab coat and do this as a
scientist, they are taking an incredibly dangerous risk. If we lose
our trust in the scientific community, all hope is gone. Scientists
will become as trustworthy as politicians, and politicians will be
able to claim that climate change is fake news.
Below
is a small and seemingly innocuous example of how a scientist,
however well-intentioned, has allowed his data to be massaged to fit
a specific agenda. This article appeared in the Dominion Post in
2017. (we don't want to pick on anyone in particular, so we have
redacted the scientist's name).
'Horrific'
deaths from soft plastic
A
third of turtles found dead on New Zealand beaches have swallowed
plastic, an expert says, and single-use shopping bags are the most
common culprit.
D**
G****, of Massey University's Coastal-Marine Research Group, said the
turtles' intestinal tract became blocked when they mistook soft
plastics for jellyfish, resulting in “horrific” deaths.
“In
the turtles that I've looked at, and [from] other studies around the
world, it's the soft, white, and translucent plastics items – so
plastic bags particularly – that are consumed in a higher
proportion than other items,” G**** said.
The Government has
been facing mounting pressure from local bodies, environmental
groups, and school children to take action over the more than a
billion plastic bags Kiwis discard annually. So far, there has been
no real movement on the problem.
G**** had studied the bodies of
roughly 80 stranded turtles over the past six years, and said of
those with plastic in their stomaches, about half had died as a
direct result.On one occasion, he was able to tell by the label that
the plastic wrapping had come from Lower Hutt.
G**** said the
argument he had heard from Environment Minister Nick Smith in the
past – that action was not needed as plastic bags made up only a
small percentage of the waste stream – failed to look as the facts,
or the environmental impact of plastic bags.
“It has a huge
impact because it looks like natural prey; it goes out in the oceans,
it doesn't break down, and they float in the water continuously until
they are either ingested or entangle an animal” he said.
Now,
before you read on, close your eyes for a second and try to form a
mental picture as to how many dead sea turtles are found
washed up on New Zealand shores annually.
Did
you guess 40, 80, 200, 1,200 ? The answer can be easily deduced from
the information above. One third of 80 is 27 sea turtles with plastic
in their stomach. Half of those, 13 turtles, had died as a direct
result. Over 6 years. So 2 deaths per year. And these deaths were
attributed to “plastic”. Curiously, the author did not narrow the
category of plastic down in this particular sentence to “soft
plastic”. There is research data available on this subject. It
varies by species, but sea turtles tend to ingest more hard plastic,
especially in the open ocean, simply because hard plastics survive in
the open ocean much longer than soft plastics. Hard plastic, by its
nature, lodges in the gut more easily than soft plastic, and is thus
more likely to kill the animal.
In
one of the cases Mr G**** mentions that he was able to tell that the
plastic wrapping had come from Lower Hutt. If the clue that he used
the word “plastic wrapping” didn't give it away, then the fact
that it had a label on it means it was obviously not a supermarket
bag. It was almost certainly a piece of cling film, sea turtles'
second favourite soft plastic, with a sticker attached. A fact that
Mr G**** would have been well aware of, but failed to clarify. He
also would have been well aware, but failed to mention, that their
favourite man-made soft material is rubber balloons (Helium balloons
freeze at high altitude and when they burst, form stringy “legs”
which are visually attractive to turtles). Which makes a nonsense of
Mr G****'s opening statement. He ends with a stunning quote (and not
just his assertion that HDPE bags don't break down). For a person
involved in marine research, Mr G**** doesn't appear to have spent
much time in the water. As children, you may well have tried once to
catch a fish in a plastic bag. You would have soon realised that it
is practically impossible, even when you are moving the plastic bag
as fast as you can. While drifting on the tide, the idea that a
plastic bag could entangle a marine animal is simply ludicrous. Ask
almost any marine biologist.
What
we don't understand is that Mr G**** must be well aware that that his
article dramatically misrepresented the facts, and that other
factors, like fishing by-catch and degradation of nesting habitats,
are threats several orders of magnitude larger to turtles' survival
than single-use shopping bags. Why, we ask ourselves, would he risk
his reputation, and the reputation of the scientific community in
general, over HDPE bags? Mr G****, if you ever come across this page,
we would love to hear from you.
---
Here
is an interesting TED talk that sums up how we feel about how
certain sections of the Environmental movement have hijacked truth
and reason (for MSG, think single-use plastic bags).
Environmental
Exaggeration