Link Between Chlorine and Asthma | The Jackal

18 Apr 2011

Link Between Chlorine and Asthma

Checking out your drinking water might be a good idea if you or a family member has asthma and allergies.  A recent Belgian study concluded that chlorine, a common chemical added to water to help kill bacteria, could be making asthma in children worse.  Fumes from chlorine in pools, and even in the shower, could trigger an attack for some people with asthma and allergies.

Those who suffer from asthma and allergies are often sensitive to gases that are produced when chlorine sanitizes bacteria in sweat or urine.  These gases can build up in an enclosed shower, irritating the lungs.

Scientists consider chlorine one of the most toxic elements found in nature. Exposure to chlorine vapour can create adverse health effects, especially for allergy and asthma sufferers. The Asthma Foundation has estimated that 1 in 4 New Zealand children have asthma.

Synthetic chemicals are all around us: in the products we use, the clothes we wear, the food we eat, and the air we breathe. It's no wonder that many people have become sensitive to these chemicals. In fact, it's estimated that 15 percent of the population has become sensitised to common household and commercial products like chlorine, bleach, detergent, cosmetics, perfume, and paints.

Chemical sensitivity is defined as an adverse reaction to toxic chemicals in the air, food, and water. It can affect your breathing, digestion, and heartbeat, as well as cause headaches, arthritis, and urinary tract infections. Judgment, perception, and memory may also be impaired. Other symptoms include bloating and gas after eating, irritability, extreme fatigue, muscle and joint aches and recurring throat infections. Almost 30 percent of those diagnosed with chemical sensitivity are exposed to chemicals at their jobs. Special testing is available to diagnose chemical sensitivity and treatment will depend on the type of chemical involved. The best treatment is to avoid or eliminate the harmful chemicals.

Clean water is one of the most important requirements. It is a sad fact that something as essential to life as clean drinking water can no longer be granted to us. Unsafe water is not just a third world problem. Despite our obvious advantages, New Zealand’s water quality is woefully lacking with many areas having an E rating. This means that the water is unsafe to consume.

More than 700 organic chemicals have been identified in drinking water and some of them are suspected cancer-causing agents. There are around 35,000 pesticides containing 600 chemical compounds. Many of these chemicals are known to cause birth defects, nerve damage, sterility and cancer. Chlorine, the chemical used to keep swimming pools clean, may increase a child's risk of developing asthma, the results of a new study indicate. In recent years, the incidence of childhood asthma has risen dramatically.

In Ireland, researchers carried out tests on 226 healthy children who swam regularly, in order to determine the levels of lung proteins in their blood. An increase in these proteins indicates that the cells lining the lungs have been damaged, which can lead to asthma. The researchers also measured the lung proteins in 16 children and 13 adults before and after exposure to an indoor chlorinated pool. As well as this, they studied relations between pool attendance and asthma prevalence in 1,881 children. The study found that those who attended pools regularly, whether they were swimming or not, were most likely to have high levels of lung proteins. However those who swam most often had protein levels similar to that of a regular smoker.

It appears that when chlorine reacts with organic matter in a swimming pool, such as sweat or urine, a mixture of potentially harmful chemicals result, which is then inhaled by people.

Belgian researchers tracked asthma rates among hundreds of primary school children and found they rose with the length of time, spent swimming in chlorinated pools. Based on these findings, the Belgian researchers concluded that 'the increasing exposure of children to chlorination products in indoor pools might be an important cause of the rising incidence of childhood asthma and allergic diseases in industrialised countries'.

Children who swim in public pools are more likely to suffer from asthma because chlorine irritates their lungs, according to the first major study of the disinfectant's possible health risks. The high concentrations of chlorine in the air above swimming pools were found to irritate the epithelium, the lining of the lungs so severely that it breaks down. It then becomes easier for pollens, dander, smoke and other irritants to cross the barrier and set off an asthma attack.

The finding offers an unexpected explanation for why asthma rates have risen so sharply over the past few decades in industrialized countries, including Canada, the researchers say. But it also undermines standard medical advice, which holds that asthmatics should avoid exercising in cold, dry air because it can aggravate the lungs. The moist, warm air of indoor swimming pools is often touted as the perfect alternative.
"The belief that the swimming pool environment is safe is so deeply rooted in our minds," the researchers write in their paper, released in the British journal Occupational and Environmental Medicine.

Blood test, given to 29 adults during the study, also analysed a certain protein that indicates damage to the epithelium. It showed the level of epithelial damage due to inhaled chlorine varied consistently with the length of time spent breathing the chlorine rich air of a swimming pool. As the team expected, asthma rates in the larger group showed the same trend. "These changes are far from being negligible," the report says.

Dr. Ken Chapman, director of the Asthma Centre at Toronto Western Hospital, said the results are "disturbing," but pointed out they were preliminary findings and said more research should be done on the dangers of swimming pool chlorine. One of the study's authors, Dr. Alfred Bernard, a toxicologist at the Catholic University of Louvain in Belgium, said he was surprised to find no serious epidemiological study of the health dangers of chlorine in swimming pools. In his paper, he urged policy-makers to rethink its widespread use and to switch to another disinfectant or improve air-quality monitoring.

"This lack of concern is also reflected in the existing regulations, which in most countries ... are focused on the microbiological quality of pool water, largely ignoring the air quality," wrote Dr. Bernard and his co-authors, all either toxicologists or respiratory specialists from three Belgian universities, with an Australian co-author.

Dr. Chapman compared chlorine's toxic effects to sulfur dioxide, a common environmental pollutant that is also thought to irritate the epithelium.

A 1998 Health Canada report found that 13% of Canadian students aged 5 to 19 suffered from asthma, with a range from 9.7% in Sherbrooke, Que., to 18% in Prince Edward Island. The most commonly cited factors that trigger asthma attacks among these students were colds (86%) followed by exercise (75%), pollen, flowers, grass, plants or trees (58%), tobacco smoke (55%), dust (55%), cold air (53%) and pets (47%).

A more recent Health Canada report found that, although asthma is more common among children, it also affects roughly 5% of adults, making it "one of the most prevalent chronic conditions affecting Canadians."