This first-person account from National Geographic details the reporter David Ewing Duncan's quest to identify the chemicals his body has absorbed over his lifetime.

His story began a year ago, shortly after a battery of 14 blood tests to find levels of 320 chemicals residing in his body, acquired "by merely living." Like, for example, chemicals absorbed from the dump near his boyhood Kansas home that's now an EPA superfund site.

Recently, Duncan was told, among other alarming news, that his test for the presence of flame-retarding compounds called polybrominated diphenyl ethers (PBDE's), which can interfere with thyroid function, cause reproductive and neurological problems, and hamper neurological development, showed alarmingly high levels -- 10 times the average found in U.S. residents and more than 200 times the average for Swedes.

The probable cause was extensive air travel (some 200,000 miles annually) leading to exposure to airplane interiors sprayed with flame retardants.

Other chemicals that were found in his body include PFOA's, PCB's, mercury, and phthalates.

Duncan notes that several illnesses have been rising mysteriously, such as autism, leukemia, male birth defects, and childhood brain cancer, and notes that some experts suspect a link to the many man-made chemicals in our food, water, and air.

Dr. Mercola's Comment:

Often, I share studies about the toll the toxic chemicals all around us -- think mercury and perfluorooctanoic acid (PFOA) -- can take on our bodies. But the often-toxic results I report may seem a bit abstract, allowing you to feel a false sense of security. I suspect you'll feel quite differently from now on, after reading this awesome story.

Incidentally, the growing curiosity about the chemicals in his body, such as polybrominated diphenyl ethers (PBDE), pushed the reporter to test his body for mercury after eating swordfish, one of the most toxic fish around, and halibut.

After taking a blood test 24 hours after eating the fish, his levels of mercury had more than doubled to 12 micrograms per liter, a frightening climb, says one scientist, considering children have experienced measurable losses in IQ with mercury levels in their blood at 5.8 micrograms.

That's why I urge you so often to take control of your health by making some common sense lifestyle changes. One good way to avoid toxins is to eat organic.

Where traditional farmers apply chemical fertilizers to the soil to grow their crops, organic farmers feed and build soil with natural fertilizer. Traditional farmers use insecticides to get rid of insects and disease, while organic farmers use natural methods such as insect predators and barriers for this purpose.

Traditional farmers control weed growth by applying synthetic herbicides, but organic farmers use crop rotation, tillage, hand weeding, cover crops and mulches to control weeds.

The result is that conventionally grown food is often tainted with chemical residues, which can be harmful to humans. The Environmental Protection Agency (EPA) considers 60 percent of herbicides, 90 percent of fungicides and 30 percent of insecticides to be carcinogenic.

Pesticides can have many negative influences on health, including neurotoxicity, disruption of the endocrine system, carcinogenicity and immune system suppression.

Pesticide exposure may also affect male reproductive function and has been linked to miscarriages in women.

Aside from pesticide contamination, conventional produce tends to have fewer nutrients than organic produce. On average, conventional produce has only 83 percent of the nutrients of organic produce. Studies have found significantly higher levels of nutrients such as vitamin C, iron, magnesium and phosphorus, and significantly less nitrates (a toxin) in organic crops.

If you must buy conventional produce, there are ways to reduce your pesticide exposure.

Thoroughly washing all fruits and vegetables will help, although all pesticide residues cannot be removed by washing. You can also remove the outer layer of leaves or peel vegetables if possible. Another alternative is to grow your own vegetables, although this takes space, time and climate considerations.

Other ways to avoid environmental toxins include:

Rather than eating fish, which is largely contaminated with PCBs and mercury, consume a cleaner source of high-quality omega-3 fats such as krill oil.

Avoid processed foods -- remember that they're processed with chemicals!

Only use natural cleaning products in your home, and switch over to natural brands of toiletries, including shampoo, toothpaste, antiperspirants and cosmetics.

Avoid spraying insect repellants that contain DEET on your body. There are safe, effective and natural alternatives out there, like Neem-Based Botanical Outdoor Gel.

Remove any metal fillings as they're a major source of mercury. Be sure to have this done by a qualified biological dentist.

Avoid artificial food additives of all kind, including artificial sweeteners and MSG.

Limit your use of drugs (prescription and over-the-counter) as much as possible. Drugs are chemicals too, and they will leave residues and accumulate in your body over time.