Researchers have found 167 chemicals, pollutants, and pesticides in the blood and urine of nine adult Americans. The study, which was led by Mount Sinai School of Medicine in New York, in collaboration with the Environmental Working Group and Commonweal, appears in a recently published edition of the journal Public Health Reports (Thornton, et al. 2002). It is the first publicly available, comprehensive look at the chemical burden we carry in our bodies.
In their report, Body Burden, Environmental Working Group says, "None of the nine volunteers works with chemicals on the job. All lead healthy lives. Yet the subjects contained an average of 91 compounds each – most of which did not exist 75 years ago."
Scientists have not studied the health risks of exposures to complex chemical mixtures, such as those found in this study. For two-thirds of the chemicals found, many of which are banned, researchers have partially studied the extent to which these chemicals individually can harm human health. They have found that these compounds can threaten nearly every organ in the body at every stage of life, from cancer to nervous and immune system damage.
The blood and urine from the nine volunteers were tested for 210 chemicals that can be divided into seven basic groups: PCBs, dioxins and furans, organophosphate pesticide metabolites, phthalates, other semivolatile and volatile chemicals, and metals.
Of the chemical groups tested, the most prevalent were those contained in 24 classes of semivolatile and volatile chemicals, with 77 detected. These classes include well-known industrial solvents and gasoline ingredients, such as xylene and ethyl benzene, that are used in a variety of common products like paints, glues, and fire retardants. The laboratory found 48 PCBs in the nine people tested. PCBs were banned in Canada and the United States in the 1970s, but are recycled for some electrical equipment and are used in other countries. They persist in the environment for decades. Lead was found in all 9 participants, and methyl mercury was found in 8.
It is increasingly evident that background exposures to industrial chemicals and pesticides are contributing to a portion of the steady increase in some health problems.
What Is a "Safe Dose"? Graphic missing
The Dose Does Not Make the Poison
Hundreds of studies in the peer-reviewed literature show that adverse health effects from low dose exposures are occurring in the population, caused by unavoidable contamination with PCBs, DDT, dioxin, mercury, lead, toxic air pollutants, and other chemicals. The health effects scientists have linked to chemical exposures, in the general population, include premature death, asthma, cancer, chronic bronchitis, permanent decrements in IQ and declines in other measures of brain function, premature birth, respiratory tract infection, heart disease, and permanent decreases in lung capacity.*
A growing body of literature links low dose chemical exposures in animal studies to a broad range of health effects previously unexplored in high dose studies. In low dose testing, scientists are using sophisticated techniques to measure subtle but important changes in the functioning of apparently undamaged organ systems, including alterations in immune function (such as antibody response), enzyme activity, hormone levels, cellular changes in tissues, neurobehavioural parameters, organ growth, and hormone and neurotransmitter receptor levels.
Importantly, many low dose effects are detected following exposure in the womb or during early childhood development. These tests focus on the effects of chemical exposures at levels that occur in the general population, far below the so-called safe levels. Scientists are finding that low doses of chemicals can be far more harmful than previously believed.
For instance, through low dose studies of bisphenol A, a plasticizer chemical commonly used in dental sealants and plastic water bottles, scientists have revealed health effects at levels 2,500 times lower than EPA's "lowest observed effect" dose, with adverse outcomes ranging from altered male reproductive organs and aggressive behaviour, to abnormal mammary gland growth, early puberty, and reduced breast feeding.
Meanwhile the chemical industry continues to claim that low dose exposures to hundreds of chemicals simultaneously are safe. These claims, however, are nearly always based on a lack of scientific information, not on a definitive, scientific proof of safety.
High dose animal studies provide the foundation for government exposure limits for contaminants in consumer products, drinking water, food, and air. Indeed, the regulatory system for chemical exposures is dependent on the notion that high dose studies reveal all the toxic properties of a chemical being tested. We now know that this is not true.
Tests Miss the Effect
A number of factors, each of which can be as important as the exposure dose, determine a compound's toxicity, including the timing of exposure, genetic vulnerability and the spectrum of responses. For example, some individuals are 10,000 times more sensitive to airborne particles, including allergens and pharmaceuticals.
Another problem is that the toxicity of mixtures is almost never studied. Current high dose studies, like those required for pesticides used on food, are conducted with purified single chemicals. In the real world, people are exposed to low dose mixtures of several hundred chemicals. Scientists do not understand the toxicity of these mixtures, and with few exceptions are not investigating them.
What You Can Do
Demand:
- that the Canadian government get on with the testing they are supposed to do under the Canadian Environmental Protection Act.
- that the chemical industry make all its test results public on the internet and to government.
Personal:
- Eat fewer processed foods, less meat and high fat dairy products, and more organic produce.
- Eat wild salmon, not canned tuna.
- Don’t microwave food in plastic; use glass or ceramics.
- Avoid artificial fragrances and reduce the personal care products and cosmetics you use.
- Avoid breathing gasoline fumes.
- Don’t use stain repellants, and reduce the household cleaners you use.
* NOTE TO THE READER: An asterisk * indicates that the Watershed Sentinel has removed the numerous research citations from this text. The full report and all references are available at www.ewg.org/reports/bodyburden. On that site, you can also take an eye-opening "virtual" body burden test to assess your own exposure.
What The Tests Found in Nine Healthy Volunteers
Cancer: 76 carcinogens in nine people. On average, each person contained 53 chemical carcinogens.
Between 1992 and 1999, cancer incidence in the US increased for breast, thyroid, kidney, liver, skin and some forms of leukemia. The incidence of childhood cancer increased by 26 percent between 1975 and 1999. The incidence of testicular cancer also rose between 1973 and 1999.* The probability that a US resident will develop cancer at some point in his or her lifetime is 1 in 2 for men and 1 in 3 for women.* Just 5 to 10 percent of all cancers are linked to inherited, genetic factors.*
Major nervous system disorders: 94 chemicals in nine people. On average, each person contained 62 nervous system toxicants.
Several recent studies have determined that the reported incidence of autism may be increasing, and is now almost 10 times higher than in the mid-1980s.* The number of children being diagnosed and treated for attention deficit disorder and attention deficit hyperactivity disorder has also increased dramatically in the past decade.* The causes are largely unexplained, but environmental factors, including chemical exposures, are considered a potential cause or contributor.
Defects of the reproductive system: 77 chemicals in nine people. On average each person contained 55 reproductive toxicants.
Studies show that sperm counts in certain parts of the world are decreasing.* Incidence of hypospadias, a birth defect of the penis, doubled in the United States between 1970 and 1993, and is estimated to affect one of every 125 male babies born.* The incidence of undescended testicles (cryptorchidism) and testicular cancer also appears to be rising.* Several studies have suggested links between developmental exposure to environmental contaminants and cryptorchidism or testicular cancer.*
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[From WS April/May 2003]