Filed under: J500 Week 11 | Tags: 2009 Water Quality Report, chlorine, cholera, dangers of chlorination, Lawrence Public Works, nerve gas, ozone purification, UV light purification, World War I
“Don’t drink the water!” The only time I’ve heard those words were near a swimming pool. After an early experiment with trying to drink pool water I learned its truth. Whether it’s the little kids or the chlorine, pool water makes you sick.
After looking into the Lawrence Public Works’ 2009 Water Quality Report I found that atrazine can cause reproductive cancer. As I scrolled through the list of other contaminants in Lawrence water I wondered which might be dangerous. Nothing caught my attention until I noticed our chlorine levels are .2 parts per million (ppm) more than the legal limit.
This is frightening because according to the U.S. Council of Environmental Quality, “Cancer risk among those drinking chlorinated water is 93% higher than among those whose water does not contain chlorine.”
The EPA set the legal limit (Maximum Contamination Level) for chlorine at 4 ppm. Any level above that is illegal. At 3.8 ppm, we have more chlorine in our water than almost any other chemical. Clean pool water can upset the stomach and a swimming pool‘s levels are usually only 2-3 ppm.
In World War I chlorine was the first poison gas used in warfare. It attacked soldiers’ respiratory systems and killed thousands within minutes. Such concentrated doses were rarely used since then but chlorine stayed around.
Governments favored chlorine as a water disinfectant. With its help people stopped the persistence of typhoid and cholera. But they did so with risk.
When the element enters a water system it breaks down into trihalomethanes, which are Class B carcinogens. Class B carcinogens are labeled such because they are known to cause cancer in animals, but not humans. (However, this doesn’t mean that a study was ever conducted on humans so to me it’s still possible.)
A 1994 EPA study listed chlorine as “especially harmful” to soil and and marine life. It is intended to kill microorganisms; side-effects are expected. Rumored side-effects include skin irritation, colon cancer and other gastrointestinal complications. Chlorine seems to be most dangerous during its application, when workers are in direct contact with the substance.
Why does Lawrence need so much chlorine in its water? Aurora Shields, Lawrence Water Quality Manager, said that though 3.8 ppm was the highest level Lawrence contamination averaged closer to 3 ppm. That is 3 milligrams of chlorine in every liter of water.
Shields said the city used a safer ammonia-based hydrochlorite option instead of pure chlorine. The levels weren’t dangerous, she said, because they could be legally higher. Because of our utility infrastructure, Shields thinks chlorine is the only viable option for current water disinfection. She said that she feels safe drinking Lawrence tap water regularly.
Chlorine manufacturers seem to be aware of their product’s negative light. Most chlorine mishaps happen en route to the water system so they focus on transportation safety. Compared with a direct leak of the chemical, chlorine contamination in water is negligible. I wonder if it’s this sort of relative situation (“At least it’s not a spill”) that keeps us satisfied with chlorine levels.
Though chlorine protected us from cholera I don’t think we should use it because of past practice. Just as cholera is a former disease so should chlorination should be an former practice. Now we can clean our water with ozone filters and UV light. This would clean our water better and leave it healthier for future generations.
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