Chemicals and Man
Do we understand the interaction?
|A man and a machine apply weed killer and fertilizer to a Price lawn in the 1940's. How much does the use of now banned chemicals applied then affect peoples bodies today? Is there still residual from those practices? And what about what people are using now?|
In one of the largest studies of chemical exposure ever conducted on people, the United States Centers for Disease Control and Prevention reported in 2005 that most American children and adults are carrying in their bodies numerous kinds of pesticides and poisonous compounds used in various products. Worse yet, many of those substances are known to cause health problems.
More recently, this past spring the Oregon Environmental Council tested the blood and urine of 10 Oregonians for almost 30 toxic chemicals. When the results came back, each person tested had at least nine of the chemicals in their bodies.
"I've lived in the same community for most of my life,'' said Vicki Berger, of Salem, Ore., one of the people who volunteered for the study. "And although I haven't lived in industrial areas, I still have all these pollutants in my body.''
It's a dilemma all Americans face and one they have little control over. In some areas certain kinds of diseases run rampant without anyone really knowing what causes the problems, until a study is done. And sometimes even studies are not conclusive about the causes.
The Oregon study marked the first time toxic chemicals had been tested for their presence in Oregonians. Other studies have shown similar levels in residents of Washington and other states.
Normally, people think of pollution in their bodies from living next to a smokestack, but really, a lot of these exposures are coming from the food you eat and everyday consumer products like the shampoo you use,'' said Renee Hackenmiller-Paradis, program director at the Oregon Environmental Council.
All the levels found in the Oregon residents fall well under Environmental Protection Agency thresholds. And the sample size is too small to generalize about levels in the state's population.
Yet it brings up a point that people have been thinking about for years.
How much of a disease pattern in a family is genetic and how much is environmental.
It also begs the question of communities as well. Why do some innocuous communities seem to have higher rates of cancer or other chronic diseases with no apparent reason for the higher rates.
Carbon residents have long suspected that cancer rates in certain communities have been brought about by environmental factors. Some say it was the coal mining with the dust in the air and miners bringing it home on their bodies. To some that meant higher rates not only for the miners themselves, but for their families too.
Others blame radon for some health problems. It is a tasteless, odorless gas that over many years of exposure can lead to various chronic maladies.
Still others say that the real problem in Carbon County came from the atomic testing in Nevada during the 1950's and 60's. While most people think of downwinders only being from southern Utah, new information points to the fact that many of the hottest spots for descending radioactivity were much farther, some as distant as New York state.
Others point to the genetic differences between Carbon County and much of the rest of Utah. Many people who settled here were from eastern and southern Europe, a genetic pool very different from those of northern Europe. Weaknesses in genetic lines have the potential to relegate some diseases to the back burner while bringing others forward, especially when mixed with environmental factors.
Regardless of the source, the CDC tests show that people have many different substances in their bodies. Companies that produce or use these chemicals warn that studies showing chemicals in the human body are not reason to eliminate the chemicals.
"The public should not be misled into thinking that the products of chemistry are inherently dangerous just because chemicals can now, through improvements in analytical chemistry, be detected at trace levels in people's blood or urine,'' the American Chemistry Council said in a statement. ``Biomonitoring indicates presence. It doesn't mean there is a significant health risk.''
In the Oregon case the OEC tested for familiar chemicals such as mercury, pesticides and PCBs. It also tested for some less-familiar names such as:
Phthalates, a class of 25 chemicals used in consumer products to soften plastics, carry fragrances and act as solvents and fixatives
Perfluorinated compounds, often used in protective coatings on cooking pans, and water and grease repellents for clothing and furniture. There are few studies regarding health effects in people, but animals studies show these chemicals damage organs.
Bisphenol A. The building block of polycarbonate plastic for some baby bottles, reusable water bottles, plastic utensils, compact discs and coatings that line food containers. In animal studies, they have caused reduced sperm count and impaired immune system functioning.
|A post World War II crop spraying operation in Carbon County.|
Chemicals find their way into people's bodies in several ways. For example, some chemicals such as phthalates in shampoos can be absorbed through the skin. Others, such as the perfluorinated compounds, can collect in household dust and then be breathed in. Pesticides found in foods can directly enter the body when the food in eaten.
The report documented bigger doses in children than in adults of many chemicals, including some pyrethroids, which are in virtually every household pesticide, and phthalates, which are found in nail polish and other beauty products as well as in soft plastics.
The 2005 CDC report which looked for dozens of toxic compounds in about 2,400 people was claimed to be the largest study of its kind to date.
Recent fears about lead use in the Chinese manufacture of children's toys has brought peoples attention to the problem of chemicals in the living environment even more. However, lead levels in the children in the 2005 study showed that they had declined over several years. The study compared lead in children living today with that of those tested in the 1970's when over 88 percent of kids tested had high levels of lead. The 2005 study showed less than 2 percent had elevated levels.
However, at the time, the study showed that there were more than 100 substances that were not natural to the body in humans tested.
Many experts felt the study showed that human beings have polluted the environment so much that the backlash from mother nature had come to roost.
The report only showed what chemicals existed in people tested but did not assess the health threat the chemicals might pose. They even made a point that a measurable amount of a compound in the human body does not mean it causes any kind of disease. But in many cases the CDC has limited information on what amounts may be harmful or if some type of combination could be a causation for disease of damage.
One of the biggest questions and surprises in the study was about pyrethroids levels in people. Pyrethroids were developed from compounds in plants and flowers and synthetically enhanced. They have been one of the bullwarks of pesticides that were considered much safer than old kinds of pesticides such as DDT and Diazonon. However, they work because they affect the nervous system of their targeted pests. Pyrethroids are used in agricultural and household pesticides. They are also one of the main weapons used by many public agencies to kill mosquitoes.
While the CDC will not commit to the idea that the chemicals being absorbed, breathed and swallowed will cause problems in humans, some researchers say that the links are fairly direct.
Research on animals hint that many of the compounds cited in the CDC study can affect various organs including the brain and the immune system.
In the world of research chronic, long term exposure to many compounds has not been studied intensively, although that is changing. The CDC is a scientific organization that works on the principles of proof. If something hasn't been proved it is just conjecture, no matter what the anecdotal evidence suggests.
Some environmentalists have been working toward having laws enacted that would make chemical companies test chemical compounds more extensively.
Probably the biggest fear many people have concern children. While it is obvious that children will not only be exposed to new compounds for a longer time than adults, their bodies also tend to amass chemicals in higher rates and hold them strongly. Some tests show that the younger children are the more they are suceptable to this process, and in fact tests on animals show that young animals and their fetuses can be harmed more than those exposed later.
In the same CDC study, nearly 6 percent of women of childbearing age had mercury that exceeded the level that the Environmental Protection Agency deemed safe to a developing fetus.
Within the next year the CDC plans to extend the study and look into over 300 more chemcials that may plant itself inside the human body.
That is a small drop in the bucket considering that there are over 80,000 chemicals in use today and the rate of new chemicals coming on the market each year is presently at about 1,500.
While it is impossible to avoid the chemicals that are in the environment, and despite the fact that science is not really sure on a lot of them whether they can cause body damage or disease, everyone can cut down the chemicals going into themselves by following a few simple steps.
Unchecked and unprotected, hazardous chemicals can easily enter and attack the body. Be aware of the chemicals used around the house and at workplaces. Take a minute to become familiar with product warning labels and Material Safety Data Sheets.
Here are some other tips.
Avoid breathing chemicals. Use chemicals only with proper ventilation and use a respirator if appropriate.
Avoid skin contact with chemicals. Wear gloves and other protective clothing.
Use and store hazardous chemicals away from food and always wash hands before eating.