The Connection Between Chlorine and Asthma

Is Your Family in Harm's Way?

Several years ago, at the 2000 Olympic games in Sydney, Australia, the United States swim team astoundingly announced that more than one-fourth of its members suffered from some degree of asthma. This high rate of asthma symptoms among competitive swimmers inspired several health researchers to find an explanation and cause for the disproportionate number of asthma cases among the swim team members. The studies produced some alarming results.

Although chloramines and Trihalomethanes (THMs) have long been known to be agitators of asthma and its symptoms, studies have now proven that these harmful chemicals may actually cause asthma in previously healthy individuals.

The truly frightening aspect of this finding is that you and your family are likely exposed to these asthma-inducing chemicals every day.

Chlorine, when combined with organic substances (such as skin particles, hair follicles, water-borne bacteria, and even sweat and urine), forms THMs. Two recent European studies deeply scrutinized these substances in order to determine their negative health effects. Researchers found that nitrogen trichloride, one of the many known THMs, was a main culprit in many forms of occupational asthma. Fortunately, once the study participants were removed from exposure to the harmful chemical, their asthma symptoms showed dramatic improvements over a relatively short period of time. Many of the participants were even relieved of the burden of steroid inhalers!

Dr. K. Thickett, a physician in the occupational lung diseases unit at the Birmingham Heartlands Hospital, conducted one such study in which workers suffering from asthma or asthma symptoms at an indoor swimming pool were analyzed. The study participants were asked to change jobs and move away from the swimming pool. Amazingly, each of the subjects either stopped taking inhaled steroids, altogether, or noticed a significant dissipation in their asthma symptoms as a result of this measure. Explaining the reason for these results, Dr. Thickett stated, “It isn't just the exposure to the chlorine that is causing asthma in swimmers. [What is] more important is the chemical reaction that takes place when chlorine mixes with sweat, urine, skin, and hair, and releases derivatives such as aldehydes, halogenated hydrocarbons, and chloramines, all of which contribute to asthma.”

Prolonged inhalation of levels of THMs and such chlorine gases as those found near an indoor swimming pool, will not only cause asthma, but will irritate the sensitive areas in the eyes, nose, and throat, as well.

Amazingly, the chemicals found near indoor pools constitute only about 1/4 of the chemical vapors that result from showering in chlorinated water!

Dr. Thickett summed her study by stating, "Our results show that nitrogen trichloride is a cause of occupational asthma in swimming pool workers, [such as] lifeguards and swim instructors." The good news is that the effects of exposure were reversible and that the asthmatic symptoms all but disappeared once the subjects were placed in a new environment, free of chlorine gas.

A second study, conducted by Dr. Simone Carbonnelle of the industrial toxicology and occupational medicine unit at the Catholic University of Louvain, involved 226 healthy school children with an average age of 10. The study participants were followed to determine how much time they spent around swimming pools and how that amount of time affected the condition of their lung tissue. The results of the study were quite conclusive and showcased further evidence for the link between harmful THMs, chlorination byproducts, and asthma symptoms.

In her study, Dr. Carbonnelle exposed the children to air around the school's swimming pool for an average of just over fifteen minutes per day. After analyzing the study results, she found levels of lung tissue damage in the children that were directly proportional to the amount of time the children spent around the pool.

In some study participants, Dr. Carbonnelle was shocked to find levels of tissue damage that were similar to what she would expect to find in a heavy smoker.

Concluding her study, Dr. Carbonnelle explained, “These findings suggest that the increasing exposure to chlorine-based disinfectants used in swimming pools, and their byproducts, might be an unsuspected risk factor in the rising incidence of childhood asthma and allergic diseases.” The dangerous chemicals to which Dr. Carbonnelle was referring are the same THMs and chloramines we are exposed to in our homes every day, due to showering, washing clothes, washing dishes, flushing toilets, and running the tap.

Even Ralph Riley, head of the National Pool Water Treatment Advisory Group, admitted, "We have known for a long time that chloramines can trigger, rather than cause asthma.” These studies contradict Mr. Riley by implicating chloramines and THMs as a direct cause of asthma. Tempering his earlier statement, Mr. Riley added that the industry was constantly looking at ways of reducing the levels of chloramines while continuing to retain the necessary protection against infection in the water.

The same chlorine that results in asthma-inducing THMs and chloramines is used in our tap water, as well as in our swimming pools. The same substances found to be the major culprits of asthma symptoms in the two studies, Volatile Organic Compounds (VOCs), are found in almost every municipal water supply in North America. The health hazard created in inhaling these substances is just now coming to our knowledge.

In one recent examination of tap water contaminants, several health professionals reported, "Assessments of drinking water safety rely on the assumption that ingestion represents the principle route of exposure." In fact, it was long believed that the greatest exposure to dangerous chemical contaminants came from eating foods prepared in chlorinated water or drinking that water.

However, recent studies have shown that the greatest risk of exposure may come from inhalation of chlorinated water.

The U.S. EPA, the primary regulatory health agency in the country, has stated that every household in America on a chlorinated water system has an elevated level of chloroform gas in the indoor air. This elevated level is directly attributable to showering, washing dishes, washing clothes, and flushing toilets with chlorinated water. The fact of the matter is, every time you open a waterspout in your house, you are releasing asthma-causing substances into your household atmosphere.

We have all experienced rough, brittle hair and dry, itchy skin as a result of swimming in a chlorinated pool. These reactions in the body occur when chlorine chemically bonds with proteins in the hair, skin, and scalp. Precisely for this reason, it is recommended that swimming pool water be kept at a concentration of 1-3 parts per million of chlorine. An unfortunate finding for the health of many water consumers, however, is the fact that our tap water regularly exceeds these levels, especially during summer months when bacteria levels are at their highest.

In 1986, the National Academy of Sciences estimated that 200 to 1000 people may die in the United States each year from cancers caused by drinking or eating foods prepared in chlorinated water. Conversely, Dr. Julian Andelman of the University of Pittsburgh found that the major threat caused by these water pollutants is far more likely to occur as air toxins in the home. Andelman discovered that, in the shower, hot water will liberate about 50% of dissolved chloroform and 80% of dissolved TCE into the air. Both the heat of the water and the large surface-to-volume ratio of small droplets increase vaporization. Chlorine, TCE, chloroform, benzene, and other dangerous chemicals are readily absorbed through the lungs into the bloodstream, thus contributing to the effects of asthma.

In the past two decades, the incidence of childhood asthma has quadrupled.

Asthma is now the leading cause of hospital admission in Canada and the leading cause of student absenteeism in the U.S. Despite these appalling figures, the gold standard in asthma treatment today remains in inhaled steroid products, rather than in prevention.

Before resigning yourself or your child to a life attached to an inhaler, first try improving your indoor air quality as a preventive measure. Two precautionary tools, the BelKraft Whole House Water Filter and the BelKraft Shower Filter , will greatly reduce toxic chemicals in your water, and, by consequence, improve the air quality in your home. In this era of increasing health risks, there is no better time than now to protect you and your family from the threat of cancerous and asthma-inducing air contaminants by installing a quality home water filtration system.

*Dr. K. Thickett of the Occupational Lung Diseases Unit at the Birmingham Heartlands Hospital, Birmingham, England.

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