Health Issues: Plastics in the Food Chain

News about synthetic plastic compounds in exported pet foods and toothpaste from China caught headlines in the U.S. in 2007. Afterwards, the USDA and FDA reported that they were testing imported food additives. Officials confidently assured the public that, "There is no evidence to suggest products bound for the human food supply are contaminated."

In 2008, melamine, the white powder used to make plastic and foam, further scandalized China when it was detected in food products made for sale within the country. Thousands of Chinese children have been sickened and a few have died from melamine contamination. Because melamine is cheap and full of nitrogen, it can be added to foods like milk and yogurt and fool inspectors.

But the truth is that recent worries about plastics are just the tip of the iceberg. Researchers have been concerned for some time about the chemical compounds that make up plastic. The home environment is inundated with plastics in the form of toys, kitchen containers, house wares, clothing, furniture, and more. Plastic bags used to tote them from the store overwhelm garbage bins and landfills. Bottles and plastic wrappers land along the side of the road.

Since the 1960s, plastics in diverse forms have become more common than glass, wood, or paper on store shelves. Many useful products that save time, reduce injury, and improve quality of life are made from plastic. Plastics protect healthcare provides, shielding them from body fluids and the spread of disease. Disposable plastics reduce restaurant costs.

At the same time, plastic stays with us for a long, long time. There is no known organism that breaks down plastic in the environment, so every bit of plastic that has ever been made is very likely to be with us right now. Estimates of how long it will take plastics to be reabsorbed by the environment range from 400 years to a much longer unit of geologic time. The amount of plastic in the environment is growing and growing.

In the 1980s, people worldwide began to notice the mess of plastic that was washing up on beaches and the harm it was doing to birds and animals that became tangled in fishing line and 6-pack rings. Initiatives like the Chesapeake Bay Foundation's Clean the Bay Day program were organized to clean up debris on the beaches. Some thought they were just tidying up exercises, but organizers understood that they are also keeping some plastic out of the food chain.

According to the Chesapeake Bay Foundation, "shoreline litter is not just a public eyesore, it is harmful to wildlife, a source of toxic water pollution, and symptomatic of other, less visible forms of pollution entering local waterways."

In England, University of Plymouth marine biologist Richard Thompson has combed the beaches since the 1980s and discovered dead birds with so many small pieces of plastic in their stomachs, probably scooped up because the birds thought it was food. But animals full of plastice likely died from starvation or blockage of the intestines.

Ten years ago, Captain Charles Moore of the Algalita Marine Research Foundation took a seldom used path across the Pacific Ocean after a sailing race. On that trip across the North Pacific Gyre he saw a patch of floating plastic debris slowly swirling in the current. The garbage patch is said to be the size of the state of Texas.

There are gyres in every ocean of earth where plastic floats around and around. Plastic is swept back and forth and in and out by currents and tides. All the while, the mixed debris of plastic bags, bottles, buckets, and toys is eroding into smaller and smaller pieces.

Scientists and environmentalists have trawled to collect water samples and sort the debris to determine how many of the small particles in oceans and rivers are plastic. One-third and more of the samples contain tiny plastic pieces of the sort that birds and fish often see as their food. The tiny particles of plastic that make their way through the digestive tract become embedded in the tissue of dead animals. Captain Moore has said that "The base of the food chain is being displaced by a non-digestible, non-nutritive component which is actually outweighing and outnumbering the natural food. That is our core issue."

As the persistence of plastics in the environment becomes better understood, consumers are questioning the safety of eating fish. The Mayo Clinic says, "As good as fish are for your health, be aware of potential downsides. Some types of fish may contain significant amounts of contaminants, such as mercury, polychlorinated biphenyls, dioxins or other chemical pollutants. Fish acquire these toxins from pollutants in lakes, rivers and oceans."

More research is needed to determine the ultimate consequence to humans. The plastics accumulate in systems and can concentrate toxic chemicals. Neil Seldman of the Institute for Local Self Reliance has said that plastic is a bigger danger than global warming because it is killing the lowest common denominator in the food chain. The problem can only be eased when greater public awareness results in less use of plastic. Manufacturers who acknowledge the problem are looking into ways to create degradable plastics.

In the meantime, the most effective way to limit the amount of plastic entering the food chain is beach cleaning and using alternatives to plastic whenever possible. Consumers can avoid the use of single-use plastic bottles, containers, and packaging to send a message to producers. Recycling can extend the useful life of plastic products and keep them out of the food chain for at least for a few more years.