http://serc.carleton.edu/NAGTWorkshops/health/case_studies/plastics.html :
"Of the most devastating elements of this pollution is that plastics takes thousands of years to decay. As a result, fish and wildlife are becoming intoxicated. Consequently the toxins from the plastics have entered the food chain, threatening human health. In the most polluted places in the ocean, the mass of plastic exceeds the amount of plankton six times over. This is a large piece of evidence that leaves the problem of polluted oceans undeniable. It is upsetting that more of clean up effort is not taking place."
"The worse part is, these plastics don't biodegrade, so they brake up into tiny pieces that are consumed by fish and sea mammals. Plastic is killing more than 100,000 sea turtles and birds a year from ingestion and entanglement. "
"Chemicals in plastics are released into the water as well as the atmosphere. Fish easily become contaminated from the chemicals in the water. This is a direct link of how plastic chemicals enter the food chain"
"In fact, not only do the toxins in plastic effect the ocean, but acting like sponges, they soak up other toxins from outside sources before entering the ocean. As these chemicals are ingested by animals in the ocean, this is not good for humans. We as humans ingest contaminated fish and mammals."
"There are different types of ways that plastic is dangerous for humans. Direct toxicity from plastics comes from lead, cadmium, and mercury. These toxins have also been found in many fish in the ocean, which is very dangerous for humans. Diethylhexyl phthalate (DEHP) contained in some plastics, is a toxic carcinogen. Other toxins in plastics are directly linked to cancers, birth defects, immune system problems, and childhood developmental issues."
"Other types of toxic plastics are BPA or health-bisphenol-A, along with phthalates (mentioned above). Both of these are of great concern to human health. BPA is used in many things including plastic bottles and food packaging materials. Over time the polymer chains of BPA break down, and can enter the human body in many ways from drinking contaminated water to eating a fish that is exposed to the broken down toxins. Specifically, BPA is a known chemical that interferes with human hormonal function."
"As far as protecting yourself from contamination, it is probably best not to have a diet that consists mainly of fish, since most is probably contaminated. "
http://news.nationalgeographic.com/news/2009/08/090820-plastic-decomposes-oceans-seas.html
"The Japan-based team collected samples in waters from the U.S., Europe, India, Japan, and elsewhere, lead researcher Katsuhiko Saido, a chemist with the College of Pharmacy at Nihon University in Japan, said via email.
All the water samples were found to contain derivatives of polystyrene, a common plastic used in disposable cutlery, Styrofoam, and DVD cases, among other things"
"About 44 percent of all seabirds eat plastic, apparently by mistake, sometimes with fatal effects. And 267 marine species are affected by plastic garbage—animals are known to swallow plastic bags, which resemble jellyfish in mid-ocean"
"Once Styrofoam, for example, breaks down, the tiny polystyrene components start to sink, because they're heavier than water, Moore said. "So it's likely that this styrene pollutant is prevalent throughout the water column and not just at the surface.""
"The Ecology Center currently picks up clean, rigid plastic containers, but we encourage people to avoid buying plastics whenever possible, since most plastics are not recyclable in the same way that glass, metals, and fibers are. Plastics are typically turned into only one other product, which must be landfilled at the end of its life. As the plastics recycling infrastructure develops and viable new plastics markets emerge, the Ecology Center will evaluate the collection of other plastics, based on operational, cost, and environmental concerns."
Initial actions you might take:
"Bring your own cup or thermos
when purchasing beverages away
from home. Avoid plastic by buying in glass
or metal whenever possible. Look for items with little or no
packaging. Avoid individually wrapped
portions (cheese slices, juice boxes,
etc.) Bring your own containers and
bags to stores and refill or reuse
them. Purchase items in containers that
can be refilled. Eliminate packaging by buying in
bulk and large containers."
It affects every country and every ocean, and shows us in highly visible terms the urgency of shifting towards a low carbon, resource efficient Green Economy"
“One community or one country acting in isolation will not be the answer. We need to address marine debris collectively across national boundaries and with the private sector, which has a critical role to play both in reducing the kinds of wastes that can end up in the world's oceans, and through research into new materials. It is by bringing all these players together that we can truly make a difference.”
"Citing the harmful impact of marine debris, UNEP said some 270 species worldwide are affected by entanglement in or ingestion of the trash marine, including 86 per cent of all sea turtles species, 44 per cent of all seabird species and 43 per cent of all marine mammal species"
“There is growing concern over the potential impact on human health of toxic substances released by plastic waste in the ocean,” it added, noting that scientists are studying whether contaminants linked to cancer, reproductive problems and other health risks can enter the food chain when ingested by marine animals."
And plastics and their additives aren't just around us, they are inside virtually every one of us- present in our blood and urine in measurable amounts, ingested with the food we eat, the water we drink and from other sources.
Two broad classes of plastic-related chemicals are of critical concern for human health-bisphenol-A or BPA, and additives used in the synthesis of plastics, which are known as phthalates. Halden explains that plastics are polymers-long chains of molecules usually made of carbon, hydrogen, oxygen and/or silicon, which are chemically linked together or polymerized. Different polymer chains can be used to create forms of plastics with unique and useful properties.
BPA is a basic building block of polycarbonate plastics, such as those used for bottled water, food packaging and other items. While it has been considered benign in the form of a heavily cross-linked polymer, its bonds can break down over time, when plastics are repeatedly washed, exposed to heat or other stresses, liberating the building blocks of the chemical, which are toxic. BPA has been recognized since the 1940s as an endocrine disrupting chemical that interferes with normal hormonal function.
This January, the FDA announced an important reversal of its 2008 claims regarding the safety of bisphenol-A, expressing new concern about "potential effects of BPA on the brain, behavior and prostate gland of fetuses, infants and children," and pledging to collaborate with other federal health agencies to reevaluate the chemical's safety
Halden explains that while plastics have legitimate uses of benefit to society, their brazen misuse has led to a radically unsustainable condition. "Today, there's a complete mismatch between the useful lifespan of the products we consume and their persistence in the environment." Prominent examples of offending products are the ubiquitous throwaway water bottles, Teflon-coated dental floss and cotton swabs made with plastic PVC sticks. All are typically used for a matter of seconds or minutes, yet are essentially non-biodegradable and will persist in the environment, sometimes for millennia.
For some years now, scientists have increasingly turned their attention to what remains of the plastic debris after prolonged exposure to wave action, saltwater and solar radiation. Over time, plastics break down into very tiny fragments, known as “microplastics”. Microplastics are now being detected in ocean waters, sand and sea-floor sediments all over the world. These tiny particles, just 20 to 50 microns in diameter, are thinner than a human hair. Marine organisms such as mussels filter these particles out of the water. Experimental analyses have shown that the microplastics accumulate not only in the stomachs but also in the tissue and even the body fluids of shellfish. The implications are still unclear, but as many plastics contain toxic substances such as softeners, solvents and other chemicals, there is concern that microplastics could poison marine organisms and, if they enter the food chain, possibly humans as well.
In other cases, the debris itself can become a death trap. Dolphins, turtles, seals and manatees can become entangled in netting or fishing line. Some of them drown; others suffer physical deformities when plastic netting, fishing line or rubber rings entwine the animal’s limbs or body, inhibiting growth or development.
There is another threat associated with plastic debris as well: almost indestructible and persistent in the environment for many years, plastic items drift for thousands of miles and therefore make ideal “rafts” for many marine species. By “hitch-hiking” on floating debris, alien species can cross entire oceans and cover otherwise impossibly long distances. Plastic debris thus contributes to the spread of invasive species to new habitats, and can even destabilize habitat equilibrium in some cases
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