The Problem Explained
The Deeper Story
Plastic trash is either directly thrown or washed by heavy rains and rivers into the North Pacific Ocean. It is swept up in the currents of a gigantic swirling vortex known as the North Pacific Gyre.
An estimated 11 million tons (and growing) of floating plastic covers an area of nearly 5 million square miles in the Pacific Ocean, 700 miles northeast of the Hawaiian Island chain and 1000 miles off the coast of California.
Humans produce 100% of the plastic pollution in the ocean — and it is entirely preventable.
Approximately 80% of this plastic pollution originates on land, and 20% is produced from recreational boaters, commercial operations, maritime industries, and the military.
Many hazardous chemicals make their way into our oceans as well including: gasoline, motor oil, and anti–freeze from our cars; pesticides and fertilizers from agricultural operations; manure from stockyards and animal processing plants; and human waste from faulty septic systems and overloaded sewage treatment plants. American manufacturers admit to releasing 4 billion pounds of pollutants into our air and waterways annually.
Once in the marine environment, scientists refer to these waste products as “persistent organic pollutants” (POPs). These consist of compounds such as DDT and DDE (pesticides), PCBs (found in automobile fluids and flame retardants), and dioxins (found in herbicides and as a byproduct of waste incinerators) and many others. Collectively we humans make over 100,000 synthetic chemical compounds that take hundreds of years to break down. Many of these pollutants are known carcinogens, and are harmful to both animals and humans when ingested. Studies have also shown that these ocean-borne plastic particles contain POP levels up to a million times higher than in the surrounding sea water. For this reason, scientists refer to the Gyre as “toxic soup”.
Plastic is a petroleum-based product and a chemical compound that is insoluble in water. Due to its inherent characteristics, it attracts other similar chemicals to its surface area thereby becoming a vehicle to transport toxins. Although it is not biodegradable, plastic is photo-degradable and when exposed to sunlight, it breaks down into smaller and smaller pieces.
Small marine creatures consume these small fragments of chemical-laden plastic, mistaking them for phytoplankton. In a process called bio-accumulation, toxic compounds build up in an organism at a rate faster than they can be broken down, thus impacting the food chain from bottom to top. Ultimately, these harmful substances wind up in the seafood on our dinner plates and we thereby become subject to bio-accumulation ourselves.
Other animals such as sea turtles and birds also consume larger bits of plastic mistaking it for food. These larger fragments cannot pass through an animals’ digestive systems and have no nutritional value. With no room left for their normal food, they slowly starve to death. Albatross unwittingly feed plastic to their young, causing them to die of starvation, too. Once an animal dies and its body decomposes, all that remains is the plastic, which is then released back into the environment where it will continue to cause harm.
6. Lead: Lead is a soft gray, acid-soluble metal that exists in three oxidation states (0, +2, +4)(www.epa.gov/waterscience/criteria/library/ambientwqc/lead80.pdf). Lead is used in electroplating, metallurgy, and the manufacturing of construction materials, radiation protective devices, plastics, and electronics equipment (www.epa.gov/waterscience/criteria/library/ambientwqc/lead80.pdf). Lead pollution comes from house and car paint, manufacturing lead batteries, fishing lures, water pipes and fixtures all give off lead. Lead can cause many health problems including damage to the brain, kidneys and reproductive system. Lead can also cause birth defects and it has been shown to cause low IQ scores, slow growth and hearing problems for small children.
The Dirty Dozen:
A pesticide applied to soils to kill termites, grasshoppers, corn rootworm, and other insect pests, aldrink can also kill birds, fish, and humans. In one incident, aldrin-treated rice is believed to have killed hundreds of shorebirds, waterfowl, and passerines along the Texas Gulf Coast when these birds either ate animals that had eaten the rice or ate the rice themselves. In humans, the fatal dose for an adult male is estimated to be about five grams. Humans are mostly exposed to aldrink through dairy products and animal meats. Studies in India indicate that the average daily intake of aldrin and its byproduct dieldrin is about 19 micrograms per person.
Used extensively to control termites and as a broad-spectrum insecticide on a range of agricultural crops, chlordane remains in the soil for a long time and has a reported half-life of one year. The lethal effects of chlordane on fish and birds vary according to the species, but tests have shown that it can kill mallard ducks, bobwhite quail, and pink shrimp. Chlordane may affect the human immune system and is classified as a possible human carcinogen. It is believed that human exposure occurs mainly through the air, and chlordance has been detected in the indoor air of residences in the U.S. and Japan.
Perhaps the most infamous of the POPs, DDT was widely used during World War II to protect soldiers and civilians from malaria, typhus, and other diseases spread by insects. After the war, DDT continued to be used to control disease, and it was sprayed on a variety of agricultural crops, especially cotton. DDT continues to be applied against mosquitoes in several countries to control malaria. Its stability, its persistence, as much as 50 % can remain in the soil 10-15 years after application, and its widespread use have meant that DDT residues can be found everywhere; residual DDT has even been detected in the Arctic.
Perhaps the best known toxic effect of DDT is eggshell thinning among birds, especially birds of prey. Its impact on bird populations led to bans in many countries during the 1970s. 34 countries have banned DDT, while 34 others severely restrict its use. Still, it has been detected in food from all over the world. Although residues in domestic animals have declined steadily over the last two decades, food-borne DDT remains the greatest source of exposure for the general population. The short term acute effects of DDT on humans are limited, but long term exposures have been associated with chronic health effects. DDT has been detected in breast milk, raising serious concerns about infant health.
Used principally to control termites and textile pests, dieldrin has also been used to control insect-borne diseases and insects living in agricultural soils. Its half-life in soil is approx. 5 years. The pesticide aldrin rapidly converts to dieldrin, so concentrations of dieldrin in the environment are higher then dieldrin use alone would indicate. Dieldrin is highly toxic to fish and other aquatic animals, particularly frogs, whose embryos can develop spinal deformities after exposure to low levels. Dieldrin residues have been found in air, water, soil, fish, birds, and mammals, including humans. Food represents the primary source of exposure to the general population. For example, dieldrin was the second most common pesticide detected in a U.S. survey of pasteurized milk.
These chemicals are produced unintentionally due to incomplete combustion, as well during the manufacture of pesticides and other chlorinated substances. They are emitted mostly from the burning of hospital waste, municipal waste, and hazardous waste, and also from automobile emissions, peat, coal, and wood. There are 75 different dioxins, of which seven are considered to be of concern. One type of dioxin was found to be present in the soil 10-12 years after the first exposure. Dioxins have been associated with a number of adverse effects in humans, including immune and enzyme disorders and chloracne, and they are classified as possible human carcinogens. Laboratory animals given dioxins suffered a variety of effects, including an increase in birth defects and stillbirths. Fish exposed to these substances died shortly after the exposure ended. Food, particularly from animals, is the major source of exposure for humans.
This insecticide is sprayed on the leaves of crops such as cotton and grains. It is also used to control rodents such as mice and voles. Animals can metabolize endrin, so it does not accumulate in their fatty tissue to the extent that structurally similar chemicals do. It has a long half-life, persisting in the soil for up to 12 years. In addition, endrin is highly toxic to fish. When exposed to high levels of endrin in water, sheepshead minnows hatched early and died by the ninth day of their exposure. The primary route of exposure for the general human population is through food, although current dietary intake estimate are below the limits deemed safe by world health authorities.
These compounds are produced unintentionally from many of the processes that produce dioxins and also during the production of PCBs. They have been detected in emissions from waste incinerators and automobiles. Furans are structurally similar to dioxins and share many of their toxic effects. There are 135 different types, and their toxicity varies. Furancs persist in the environment for long periods, and are classified as possible human carcinogens. Food, particularly animal products, is the major source of exposure for humans. Furans have also been detected in breast fed infants.
Primarily used to kill soil insects and termites, heptachlor has also been used more widely to kill cotton insects, grasshoppers, other crop pests, and malaria carrying mosquitoes. It is believed to be responsible for the decline of several wild bird populations, including Canadian Geese and American kestrels in the Columbia River Basin in the U.S. The geese died after eating seeds treated with levels of heptachlor lower than the usage levels recommended by the manufacturer, indicating that even responsible use heptachlor may kill wildlife. Laboratory tests have also shown high doses of heptachlor to be fatal to mink, rats, and rabbits, with lower doses causing adverse behavioral changes and reduced reproductive success. Heptachlor is classified as a possible human carcinogen, and some two dozen countries have either banned it or severely restricted its use. Food is the major source of exposure for humans and residues have been detected in the blood of cattle from the U.S. and from Austrailia.
- Hexachlorobenzene (HCB)
First introduced in 1945 to treat seeds, HCB kills fungi that affect food crops. It was widely used to control wheat bunt. It is also a byproduct of the manufacture of certain industrial chemicals and exists as an impurity in several pesticide formulations. When people in eastern Turkey ate HCB-treated seed grain between 1954 and 1959, they developed a variety of symptoms, including photosensitive skin lesions, colic, and debilitation; several thousand developed a metabolic disorder called porphyria turcica, and 14% died. Mothers also passed HCB to their infants through the placenta and through breast milk. In high doses, HCB is lethal to some animals and, at lower levels, adversely affects their reproductive success. HCB has been found in food of all types. A study of Spanish meat found HCB present in all samples. In India, the estimated average daily intake of HCB is 0.13 migrograms per kilogram of body weight.
This insecticide is used mainly to combat fire ants, and it has been used against other types of ants and termites. It has also been used as a fire retardant in plastics, rubber, and electrical goods. Direct exposure to mirex does not appear to cause injury to humans, but studies on laboratory animals have caused it to be classified as a possible human carcinogen. In studies mirex proved toxic to several plant species and to fish and crustaceans. It is considered to be one of the most stable and persistent pesticides, with a half life of up to 10 years. The main route of human exposure to mirex is through food, particularly meat, fish, and wild game.
- Polychlorinated Biphenyls (PCBs)
These compounds are used in industry as heat exchange fluids, in electric transformers and capacitors, and as additives in paint, carbonless copy paper, and plastics. Of the 209 different types of PCBs, 13 exhibit a dioxin-like toxicity. Their persistence in the environment corresponds to the degree of chlorination, and half lives can vary from 10 days to 18 months. PCBs are toxic to fish, killing them at higher doses and causing spawning failures at lower doses. Research also link PCBs to reproductive failure and suppression of the immune system in various wild animals, such as seals and mink. Large numbers of people have been exposed to PCBs through food contamination. Consumption of PCB contaminated rice oil in Japan in 1968 and in Taiwan in 1979 caused pigmentation of nails and mucous membranes and swelling of the eyelids, along with fatigue, nausea, and vomiting. Due to the persistence of PCBs in their mothers bodies, children born up to seven years after the Taiwan incident showed developmental delays and behavioral problems. Similarly, children of mothers who ate large amounts of the contaminated fish from Lake Michigan showed poorer short-term memory function. PCBs also suppress the human immune system and are listed as probable human carcinogens.
This insecticide is used on cotton, cereal grains, fruits, nuts, and vegetables. It has also been used to control ticks and mites in livestock. Toxaphene was the most widely used pesticide in the U.S. in 1975. Up to 50% of toxaphene release can persist in the soil for up to 12 years. For humans, the most likely source of toxaphen exposure is food. While the toxicity to humans of direct exposure is not high, toxaphene has been listed as a possible human carcinogen due to its effects on laboratory animals. It is highly toxic to fish; brook trout exposed to toxaphene for 90 days experienced a 46% reduction in weight and reduced egg viability, and long-term exposure to levels of 0.5 micrograms per liter of water reduced egg viability to zero. 37 countries have banned it, and 11 other have severely restricted its use.
- The 12 chemicals in the dirty dozen are known as persistent organic pollutants (POPs).
- Production: The nine POP produced for use in agriculture were introduced from 1920 to 1950, with production peaking in the 1960s and 1970s for crops. By 1990, these substances were banned for use on crops and termite control by most North American and European countries, although they continued to be manufactured as a wood preservative, for pest control, and as intermediaries for other chemical processes. Production volumes of POPs in North America and Europe have substantially declined since the 1970s. Japan, not known to have been a major producer, produced smaller quantities of endrin, heptachlor, and HCB.
- POP production and world trade still persist. There are about 39 countries where companies report production. There are probably three more countries–Tanzania, Lebanon, and Sri Lanka–where companies or foreign subsidiaries of producing countries, formulate POPs, but these countries have poor right-to-know public reporting requirements.
- A rapid expansion of overall chemical manufacturing is occurring now in Asian countries. For the 30 largest chemical manufacturers, 14% of their growth has been in developing countries (8). Between 1980 and 1997, chemical production capabilities in developing countries increased by more than 300%. Many more locally owned chemical companies are reporting production for export and most developing countries with a chemical manufacturing base are now able to produce alternatives to POPs.
- Today it is difficult to identify the volume of POPs produced by the companies listed in the trade by international chemical directories. In 1990, Battelle Corporation in Geneva, Switzerland, developed a database on POP production that became the basis for studies conducted by Environment Canada, the OSPARCOM inventory, and the U.S. Environmental Protection Agency (U.S. EPA) (3,9,10). Battelle no longer produces this database. Environment Canada has committed resources to estimate total global production and atmospheric loading of POP substances. Reports are now complete for toxaphene and lindane. Reports for other POPs are scheduled in the next 10 years. Wood MacKenzie Company in the United Kingdom, a commercial company, tracks production of the 40 largest chemical companies that account for 80% of the world market. It reports no POP production in 1997.
- In the United States the volume of chemical production was reported by the International Trade Commission in the “Synthetic Organic Chemicals: U.S. Production and Sales” report. These data were collected annually for 78 years until the U.S. Congress stopped publication in 1996. There now is no central government reporting mechanism in the United States that reports the volume produced annually in the United States of any given chemical.
- Trade: Globally in 1997, of the top 30 pesticide-producing countries, industrial countries accounted for 85.3% of pesticides exported. Developing countries were responsible for 14.7%, a share that is growing. The PIC Agreement focuses on how to control the trade of POPs. Tools to evaluate the trade of the nine agrochemical POPs have been improved by adoption of Harmonized Tariff Schedules (HTS) between European Union (EU) countries, North America and many other countries involved in world trade.
(“Aldrin and Dieldrin: A Review of Research on Their Production, Environmental Deposition and Fate, Bioaccumulation, Toxicology, and Epidemiology in the United States.” J. Lisa Jorgenson. 2000. http://ehp03.niehs.nih.gov/article/fetchArticle.action?articleURI=info:doi/10.1289/ehp.01109s1113)
The Nasty Nine
- Pentabromodiphenyl ether
This PBDE congener, sometimes referred to as “penta,” was used as a flame-retardant in foam upholstery and furnishing. It was first banned in Germany, Norway and Sweden in the 1980s and 1990s, then in the Europe Union in 2003. The last U.S. manufacturer stopped producing the chemical in 2005, and the Environmental Protection Agency subsequently banned its production in the U.S. It is still manufactured elsewhere, primarily in China, and can be imported to the U.S. Maine and Washington have banned it and nine other states have proposed bans.
The chemical may cause a range of health problems, including liver disease and reproductive and developmental problems. It has been found in human breast milk.
2. Octabromodiphenyl ether
Like its sister “penta” this polybrominated diphenyl ether, or PBDE, has been linked to health issues and has largely been phased out in developed nations.
This insecticide, also known as Kepone, was used until 1978 in the United States on tobacco, ornamental shrubs, bananas and citrus trees, and in ant and roach traps. It is chemically almost identical to Mirex, which was one of the original “Dirty Dozen” banned by the treaty.
Workers using chlordecone suffered damage to the nervous system, skin, liver and male reproductive system. It may still be in use in developing nations, despite its being banned in the industrialized world.
An agricultural insecticide also used to treat head lice and scabies in people, lindane has been banned in 50 nations because the organochlorine pesticide can attack the nervous system. In the United States, it was used until 2007 on farms, and it is still used as a “second-line” treatment for head lice when other treatments fail.
Additionally, because Lindane is the only useful product in a family of chemicals generated to produce the pesticide, there is persistent chemical waste created by the process. For every ton of Lindane produced, six to 10 tons of waste are produced.
One of the persistent chemical waste products produced by making Lindane, alpha-hexachlorocyclohexane may cause cancer and liver or kidney problems.
Another of the persistent chemical waste products produced by making Lindane, beta-hexachlorocyclohexane may cause cancer and reproductive problems.
The company 3M used PFOS to make Scotchgard fabric and other stain-resistant products until 2002. The chemical is also used in a number of industrial processes. It is found in the bodies of people around the world, and in relatively high concentrations in Arctic wildlife — reflecting the global transport of persistent chemicals like these. Unlike the other chemicals on the “nasty nine” list, PFOS will have its use restricted, not banned.
A polybrominated biphenyl, or PBB, hexabromobiphenyl is a flame retardant that has been linked to a range of health problems, including weight loss, skin disorders, nervous and immune systems effects, and effects on the liver, kidneys, and thyroid gland. While it is no longer used in developed nations, it may still be in use in developing nations.
Used in the manufacture of an insecticide, and as a flame retardant, Pentachlorobenzene may damage the nervous and reproductive systems, as well as the liver and kidneys. It is also used as a head lice treatment and can be found in the waste streams of some paper mills, petroleum refineries, sewage treatment plants and incinerators.
v All were banned because they accumulate in the tissues of living things, including humans, because they are all but indestructible once released into the natural world, and because they can spread across the globe with weather patterns and migrating animals. Not to mention that they have been linked to a range of health issues, including cancer and reproductive and developmental problems.