Chlorine is one of the most common industrial disinfectants in the U.S., touted as an effective and cheap method to fight waterborne diseases and dangerous bacteria since the late 1800s. It's pumped into our swimming pools, public drinking water, refrigerator units, laundry solvents, dry cleaning, pesticides, paper, plastics and our household cleaning products.
But an emerging body of compelling research suggests this insidious chemical and its carcinogenic by-products are adversely affecting our health. According to the U.S. Council of Environmental Quality: "Cancer risk among people drinking chlorinated water is 93 percent higher than among those whose water does not contain chlorine." So before you sign up your children for indoor swim classes this fall, or reach for that jug of Clorox under your sink to fight those tough stains, let's take a look at the potential risks involved.
Dr. Alfred Bernard, professor of toxicology at the University of Louvain in Brussels, published a series of studies documenting the effects of chlorine in swimming pools. His 2007 report, found in the official journal of the American Academy of Pediatrics, showed airway and lung permeability changes in kids who participated in an infant swimming group, substantiating previous studies linking chlorine to asthma and recurrent bronchitis in children.
In 1993, Greenpeace issued a call to action entitled "Chlorine, Human Health, and the Environment: The Breast Cancer Warning." In this article, they flagged organochlorines as a "significant risk factor" for breast cancer, citing a study that showed 16 different organochlorines causing mammary cancers in lab animals. Additionally, a separate study in Hartford, Connecticut found that "one common factor among women with breast cancer is that they all have 50 to 60 percent higher levels of these chlorination by-products in their fat tissue than women without breast cancer."
Israel is a hot topic often cited in the organochlorine-breast cancer discussion. In the 1970s, Israel had one of the highest rates of breast cancer and contamination levels due to organochlorine pesticides. However, when the government issued an aggressive phase-out of three organochlorine pesticides (DDT, alpha-benzene hexachloride (BHC), and gamma-benzene hexachloride, commonly known as lindane) breast cancer rates dropped by eight percent between 1976 and 1986. In comparison, during that same time period, breast cancer rates increased an average of one percent annually in the United States, where only DDT was completely banned.
According to a study published in the American Journal of Epidemiology in November 2006, participants who drank chlorinated water had a 35 percent greater risk of bladder cancer compared to their counterparts. If the participants were regular pool swimmers, that risk jumped to 57 percent.
In the late '60s, Joseph M. Price, M.D., wrote a book entitled Coronaries Cholesterol Chlorine postulating that the basic cause of atherosclerosis (hardening of the arteries), heart attacks and most forms of strokes is not cholesterol, but chlorine contained in processed water. To support his position, Dr. Price carried out a series of experiments on chickens. Within months, 95 percent of the chickens that drank chlorinated water developed atherosclerosis. Years later, Dr. Richard Bull of the Environmental Protection Agency (EPA) ran a similar study with pigeons, not only backing up Price's analysis but also finding that the subjects had a 50 percent higher level of cholesterol when exposed to chlorine-treated water.
Birth Defects and Infertility
While the evidence is still largely divided concerning the affect of chlorine on infertility (some studies show an association, others do not), a relationship between chlorine and birth defects is more conclusive. To wit, the risk of heart problems, cleft palates, and major brain defects in children are almost doubled in areas where drinking water is disinfected with chlorine. This finding was based on an analysis of over 400,000 infants in Taiwan (published in Environmental Journal in June 2008), piggybacking similar results involving ventricular septal defects in Norway and the U.K.
How To Protect Yourself From The Hazards of Chlorine
1) Install chlorine filters on all the faucets in your home. And don't forget your showers! In 1992, Dr. Halina Brown published a study in The American Journal of Public Health reporting that 2/3 of our harmful exposure to chlorine/chloroform is through inhalation and absorption of the skin during shower time.
2) Purchase chlorine-free, organic tampons. These contain no polyester, rayon, plastics, or other synthetic materials and do not use chlorine chemicals to whiten the product.
3) Avoid chlorinated swimming pools, especially indoors where there's less ventilation.
4) Go organic. This applies not just to your food but also to your dry cleaner.
5) Swap out your chlorine-laden cleaning products for the all natural varieties. A plethora of green DIY recipes can be found here , or you can opt for the store-bought alternatives.
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