Radon, is it really a serious threat to health?

Radon, is it really a serious threat to health?

Yes, radon is a serious health hazard. It is a radioactive substance that comes from uranium and thorium in the rocks and soil of the earth. It leaks from the ground and into the air at the soil-air junction such as in basements. Radon quickly breaks down and attaches to air and water particles, making it easy to inhale. These particles, radon progeny, stay in the lung, emitting radiation and causing damage that can lead to cancer (from “Radon Action Month:  Why Nurses Should care about Radon Exposure,” by P. Allen, et al, Tar Heel Nurse, Winter, 2015).

Because radon primarily gets into the body through inhalation, it isn’t surprising that lung cancer is the main disease it has been linked to and is the only one officially identified by the CDC (EPA, 2015). Because it is naturally occurring, odorless, and colorless, people rarely suspect its presence. An estimated 15% of lung cancer deaths are believed to be caused by it and it is the number one cause of lung cancer in non-smokers. It is the leading preventable cause of death and decreasing it in buildings could save more lives than efforts to eliminate home fires, fall prevention and drownings, not to take away from these important measures (from J. Worrell, et al, “Radon Exposure:  Using the Spectrum of Prevention Framework to Increase Health Care Provider Awareness,” in Clinical Journal of Oncology Nursing, Dec. 2016).

Kits to measure radon levels are available at home improvement stores but in some areas, kits are offered at reduced cost through the state’s radon detection program or health departments. The kits should be placed at the lowest level where people live. For a reading of 4.0 pCi/L or greater, a mitigation system can be installed to vent the radon to outdoor air, where it is quickly diluted and no threat. Radon should be measured every few years if the level is above two or if a mitigation system is installed (American Family Physician, Audio Digest for December, 2017).

Radon can be found all over the world. In the U.S., parts of the Midwest have high rates, as does Kentucky, and the northeast. Portions of the West near fault lines may have radon problems too. The only way to really know is to use a kit to measure it. There is great variability even from one house to the next due to difference in building materials, environment, etc. Also, the U.S. population is quite mobile so current exposure doesn’t indicate lifetime risk.

Smoking is still the number one risk for lung cancer in smokers and even thought radon is the main cause in non-smokers, it is important to understand that there is a ten to twenty-fold greater risk of lung cancer from radon for smokers compared to non-smokers (Worrell, et al, 2016). To put it another way, the EPA estimates that 86% of radon-induced lung cancer deaths are found among current and former smokers (from Editorial Letters in the American Journal of Public Health, Sept. 2013, Volume 103, #9.

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Nickel and its health effects

Nickel and health

Nickel is a naturally occurring substance but isn’t known to be an essential nutrient. A few nickel compounds pose a health risk.

Probably the most common and concerning exposure to nickel is nickel carbonyl. It is found in second-hand smoke. Nickel carbonyl is a potent carcinogen. This adds to the long list of hazards for those exposed to second-hand smoke, especially children.

Those working in nickel refinery and processing plants can be exposed to nickel through inhalation. If protection isn’t used, they are at risk for lung, laryngeal and nasopharyngeal cancer.

The most common problem with nickel is from skin contact. Ten to twenty percent of people are sensitive to nickel. It is a common cause of contact dermatitis. Jewelry, including white gold items, as well as watches and earrings are typical sources. Metal fasteners on clothing, if it is in contact with skin, is another source of exposure. Allergic dermatitis from nickel is more common after prolonged contact with skin. Dental prostheses may also contain nickel and cause problems.

Nickel and nickel compounds are toxic pollutants. Per the EPA, drinking water shouldn’t have any more than 0.1 mg/L of it.

Reference:  Pediatric Environmental Health, third edition. American Academy of Pediatrics, 2012.

Chromium: The good, the bad, and the not-so-important

Chromium:  The good, the bad, and the not-so-important

Chromium is found and produced in several different forms. The most common forms are metallic, trivalent and hexavalent. The trivalent form occurs naturally and is an essential nutrient. Its needed for fatty acid and cholesterol production and insulin metabolism. It is found in eggs, meat, cheese, whole grains and certain fruits and vegetables. Metallic chromium isn’t pertinent to this article (Pediatric Environmental Health, 3rd edition, Dr. Ruth Etzel, Editor, and Dr. Sophie Balk, Assoc. Editor. Elk Grove Village, IL:  2012).

Hexavalent chromium is the toxic form. The US National Toxicology Program, World Health Organization, EPA, and International Agency for Research on Cancer have all identified hexavalent chromium as a human carcinogen. It comes mostly from industrial emissions and passes into the air, water, and soil. It’s also part of tobacco smoke. Chromium is used in so many ways it isn’t surprising it is found in more than 50% of the National Priorities List superfund hazardous waste sites as well as many landfills. Fossil fuel burning and steel production are major sources of chromium in the air. The movie Erin Brockovich was about The Pacific Gas and Electric Company’s role in the excessive chromium in water and even though it has been out a long time, this is still a real problem.

Absorption of hexavalent chromium from the lungs is high. Gastrointestinal absorption of this form can be as high as 50% but much of it is converted to the trivalent form. Chromium doesn’t stay in the body very long, so antidotes and chelators aren’t in demand. Vitamin C helps convert hexavalent chromium to the trivalent form. Laboratory assessments are not particularly useful, and environmental documentation is more helpful.

Topical chromium is a common cause of allergic contact dermatitis. Swallowing a large amount of hexavalent chromium could cause nausea, vomiting and acute kidney failure.

The biggest concern is with chronic inhalation of the hexavalent form of chromium. Those at highest risk are those working or who have worked in industries where chromium is used. These individuals have an increased chance of developing nasal and lung cancer. The latter risk increases with the duration of an exposure and there’s about a 13 to 30-year latency period. In “Profiling stainless steel welding processes to reduce fume emissions, hexavalent chromium emissions and operating costs in the workplace,” (by M. Keane, et al in Journal of Occupational and Environmental Hygiene, 2016, v. 13#1, pages 1-8) almost half a million Americans do some welding in their work, and that is a potential exposure. Gas metal arc welding was found to create less exposure to toxic gases.

In “Hexavalent Chromium Is Carcinogenic to F344/N Rats and B6C3F1 Mice” (by M. Stout, et al, in Environmental Health Perspectives, v117, #5, for May 2009, pages 716-722), the possibility of an increased risk for oral, stomach and duodenal cancer with chronic consumption of water polluted with excess chromium was raised. The research done involved giving water with various levels of hexavalent chromium in it to the test animals for 2 years. Before you decide that this isn’t relevant to humans, consider the fact that rats and mice are used in research because they share many biological processes and tissue structures with humans.

This all lends support to having water tested, including well water, before even a sip.