Poisons > Plastics
Plastic is used everywhere - from plastic bags to light fittings, from
bubble wrap to cling film (or Glad Wrap in NZ). Plastic is the common name given
to products made from oil that have undergone a chemical reaction known as
polymerisation, a process where an unimaginably huge number of small molecules
are linked together to form the plastics we use and consume today. Consume? If
you think you are not eating plastic, please read on.
Some say that we are in The Age of Plastic
Plastics have been with us for many years and new generations of hybrid
plastics are appearing as composites and laminates to create much tougher
materials used in bench tops, airplane wings, flooring, dentistry, cosmetic and
surgical tools and components.
While plastics continue to be a very useful product range, there is a growing
downside to the use of plastics. As you are no doubt aware, plastic bags
blow in the wind and plastic litters our cities, countryside and oceans. Plastic
and Plastic bags are non-biodegradable and have become an environmental curse
and a hidden killer in our midst.
Those who live or visit the coast have all seen the detritus washed up on our
beaches - the plastic bottles, bits of old fishing net and chord, broken fish
crates, bouys, cotton buds, plastic bags and all manner of stuff thrown
overboard or dumped on land which ends up in the sea.
The Eastern Garbage Patch as
it's become known, is a several hundred square mile area of floating plastic
rubbish in the Pacific Ocean that is a popular feeding place for albatrosses
and sea turtles. Thousands of them die each year after mistakenly consuming
plastic or feeding it to their young. In total over 260 marine species
worldwide have been found to have eaten plastic, and although it doesn't
always kill them immediately, it weakens them and consequently whole species
are now under threat by entanglement and ingestion.
While plastic starts its life as a
useful product, but over time it starts to break down into smaller and smaller
pieces and fragments which are to be found everywhere in our oceans where they are
known as Mermaids Tears. These are tiny but still visible particles of
plastic that are continuously degrading into ever smaller pieces and will remain
in the environment for hundreds or even thousands of years.
Researchers have discovered that if you eat any ocean fish, you may also be
eating plastic. Yes that's right, plastic just keeps breaking down into ever
smaller particles to the degree that plastic permeates the oceans of the world and at the
molecular level plastic is absorbed my marine creatures and when they are eaten by
larger fish, the particles then accumulate in their flesh and so on up through
the food chain to our dinner plate.
Ecoestrogens or Xenoestrogens
Now if you're not chemophobic, perhaps its time you were. What do plastics and
spermicides have in common? And what do they have to do with low sperm counts,
precocious puberty, and breast cancer? Read on to find out.
Estrogens are a group of hormones produced in both the female ovaries and male
testes of most species (including humans), with larger amounts made in females
than in males. They are particularly influential during puberty, menstruation,
and pregnancy, but they also help regulate the growth of bones, skin, and other
organs and tissues.
Over the past 10 years, many synthetic compounds and plant products present in
the environment have been found to affect hormonal functions in various ways.
Those that have estrogenic activity have been labeled as environmental
estrogens, ecoestrogens, estrogen mimics, or xenoestrogens (xenos means
Some arise as artifacts during the manufacture of plastics and other synthetic
materials. Others are metabolites (breakdown products) generated from pesticides
or steroid hormones used to stimulate growth in livestock. Ecoestrogens that are
produced naturally by plants are called phytoestrogens (phyton means plant).
Many of these estrogen mimics bind to estrogen receptors (within specialized
cells) with about the same affinity as estrogen itself, setting up the
potential to wreak havoc on reproductive anatomy and physiology of any animal or
human that happens to ingest them. They have therefore been labeled as
disruptors of endocrine function.
The number of substances that behave like estrogens and appear to be practically
everywhere from plastics to sunscreens, and there are thousands of examples.
Perhaps the most well known examples are the male alligators at Lake Apopka,
Florida which are declining due to rapidly diminishing penis size, the increase
in American boys growing breasts, the diminishing sperm count in American men,
and the incidence of testicular cancer, which typically affects young men in
their 20s and 30s which has increased worldwide. Numerous studies have also
implicated xenoestrogens as the responsible agents in breast cancer.
The growing number of estrogen mimics in the environment has been linked to
early puberty in girls. The normal, average age of onset is between 12 and 13. A
recent study of 17,000 girls in the United States indicated that 7 percent of
white and 27 percent of black girls exhibited physical signs of puberty by age
seven. For 10-year-old girls, the percentages increased to 68 and 95,
respectively. Studies from the United Kingdom, Canada, and New Zealand have
shown similar changes in the age of puberty onset.
Is a synthetic chemical used to make dental sealants, microwavable plastics,
linings for metal food-and-beverage containers, baby bottles, and numerous
other products. The chemical is well known to mimic the effects of estrogen
and tests had found that bisphenol-A leaches into our food and water and that
it's widely prevalent in human blood.
The FDA reported that 95 percent of baby bottles sold in the United States are
made of a hard plastic known as polycarbonate all leach out the synthetic
estrogen named bisphenol-A, especially when heated or scratched.
Studies verifying the estrogenic activity of bisphenol-A were published in
Nature in the 1930s, but it did not arouse much concern then. A 1993 report
published in Endocrinology showed that bisphenol-A produced estrogenic effects
in a culture of human breast cancer cells.
There are perhaps 100,000 synthetic chemicals registered for commercial use
in the world today and 1,000 new ones are formulated every year. While many are
toxic and carcinogenic, little is known about the chronic effects of the
majority of them. And there is growing concern about their potential
hormone-disrupting effects. The problem of exposure is complicated by numerous
carrier routes, including air, food, water, and consumer products.
Plastics are only one group of chemically made products that we will use and
eventually consume as they degrade and infiltrate our environment and food
chain. According to Dr. George Pauli, Associate Director of Science
Policy, FDA Office of Food Additive Safety in the regulations mandated in 1958,
we must assume that all plastics migrate toxins into the food they contact.
As consumers, we look for ways to maintain the status quo of our modern lives.
However, the only logic I can see in the regulation of food contact plastics is
profit at the expense of our health, the economy, society, and environment. You
needn’t be a polymer scientist to know that plastic shouldn’t contact food and
the less plastic in your immediate environment, the healthier you will be. It is
time to be real and a good grip on logic, remove plastic from your life and
Plastic debris in our oceans
Plastic density in our oceans
Hazards of environmental estrogens
Disruptors Research Initiative
Alternatives to Plastic
Tulane and Xavier Universities,
Estrogens and Other Hormones
World Wildlife Fund,
Toxic Chemicals, Endocrine Disruptors
Environmental Health Perspectives 114(January):106-112.
effect of bisphenol A disrupts pancreatic b-cell function in vivo and induces
Morgan, K. 2003. Wrong number: Plastic ingredient spurs chromosomal defects.
Science News 163(April 5):213. Available to subscribers at http://www.sciencenews.org/articles/20030405/fob6.asp.
Raloff, J. 2004. This pollutant fights lupus. Science News 165(Jan. 17):45.
Available to subscribers at http://www.sciencenews.org/articles/20040117/note12.asp.
Reused paper can be polluted. Science News 163(May 24):334. Available to
subscribers at http://www.sciencenews.org/articles/20030524/note14.asp.