Building off of my last post on the pollution of the Catawba River, I decided to look at the effects of additives that are put in drinking water to improve its overall quality, although the word “quality” is highly subjective in this sense.
Microbes are living organisms found in water. These microscopic organisms include E. coli, Cryptosporidium, Giardia lamblia, and Legionella. These microorganisms originate from a variety of places such as in fecal matter from animals and humans, to being naturally found in water. These microbes can cause a series of health issues from gastrointestinal issues such as vomiting, diarrhea, and cramps to types of pneumonia. In order to combat these microbes’ water companies, cities, or counties often add antimicrobials to water in order to prevent these health effects. Disinfectants are often added too drinking water supplies in order to kill off bacteria that if ingested, can be hazardous to humans (Escherichia coli). Chlorine based disinfectants are by far the most common in use. These disinfectants can directly cause eye and nose irritation, anemia, stomach disorders, and nervous system disorders.
Although the disinfectants cause some problems directly, a real issue arises in the byproducts formed when these disinfectants are introduced. These byproducts include Bromate, Chlorite, Haloactic acids, and trihalomethanes. These byproducts adversely affect humans by increasing cancer risks, causing problems in the liver and kidneys, and by causing complications in the Central Nervous System (CNS).
When looking at additives added to water during waste water treatment Acrylamide is a definite standout when it comes to harmful chemicals. The effects of acrylamide are more complications in the nervous system, blood conditions, and more increases risks of cancer.
I believe it is important to look at how we are trying to prevent and remove these additives from the water. The U.S Environmental Protection Agency (EPA) sets MCLG (maximum level containment goals) and MRDLG (maximum residual disinfectant level goals) which are the levels of contaminant under which there are no adverse health effects
The EPA then sets MLC (maximum contaminant levels) and MRDL (maximum residual disinfectant levels) which are the maximum levels of contaminant allowed into water without penalization from the EPA. The MLC and MRDL differ from MCLG and MRDLG because of considerations of current clean up technology and costs. Maximum levels are set as close to goals as possible after these considerations are made.
|Disinfectants and Byproducts||MCLG (mg/Ml)||MCL (mg/L)|
Although the EPA is setting contaminant levels, it is hard to say that once they have been breached that they will dilute over time, or in other words they might become a permanent part of the environment and ecosystem. Like last week I draw connections to “I Am Legend”. In that film humans mutate after taking a miracle cure to cancer. The parallel is drawn because as the people in the film ingest chemicals that are potentially harmful, as we too are ingesting chemicals that are effecting our Central Nervous System. I think we are treading on thin ice, because we do not know the long-term effects of the chemicals we are ingesting. Who knows the harm we could be causing to not only ourselves but our subsequent generations.