There is lots of controversy over whether water filters actually work or not, and if they are even necessary for people in the United States who do not have a lead problem with their water pumps. I read online that tap water is perfectly fine to drink most of the time in America, yet my roommate has a Brita water filter, and so I wanted to see if they are actually necessary.

In one study from March of 1996 published on the US National Library of Medicine (National Institutes of Health) website, the microbiological quality of filtered water through a Brita was measured in an experimental study in both households and two laboratory settings. 34 filters were tested in households, in which 24 filters increased the bacteria counts in water by as much as 6,000 cfu/ml. Out of 6 filters tested in the labs, 4 of them also increased the bacteria counts. The amount of bacteria was less in the tap water than the filtrated water after one week of use at two different temperatures, one room temperature and another 4 degrees celsius. Therefore, it was concluded that the filter in the Brita had bacteria growing on it during the week it was in use by as much as 10,000 more counts of bacterial colonies than the tap water, not filtered.

Another report from the University of Berkeley on December 6, 2000 concerning filtered water versus tap water found that using a Brita filter is okay if used simply for extra precaution and personal preference of the taste of the water, but the filter does not kill bacteria. The filter traps the bacteria which becomes a breeding ground for other bacteria. Tap water is filtered by Chlorine, yet if the filter is not changed and contains built up bacteria, it puts extra bacteria back into the naturally filtered water from tap. Tap water comes from filtered water plants and typically has low bacteria counts because of the minimal level of chlorine in the water that is safe for humans to digest and kills the bacterial cells. The problem that arises, and why people partially use filters, is because the tap water can be contaminated from the industrial pipes and drains that it goes through from plants to faucets. Some people prefer to get water through a purified bottle or use a filter because of the smell that the chlorine can cause, but it is mostly harmless. Brita filters, though they claim to remove bacteria, heavy leads, and chlorine, do not remove organic chemicals, known as THMs (tribalomethanes), that are naturally evaporated out of tap water but trapped in the filtered Brita. Brita can however be helpful in filtering out chemicals and germs from plumbing issues or other industrial metals and lead but ultimately, this resource concluded that unless there is a serious issue, Brita filters added bacteria and do not filter out microorganisms that tap water does naturally, so tap is essentially safer/purer.

From both the study and report, it seems as though Brita filters are not necessary if the tap water is not contaminated with lead. But does this mean that my roommate should stop using her Brita and drink straight from the sink? I researched Penn State’s water system to see if there was any record of issues with the filter systems or if the water would be exposed to any possible lead contamination or any related contamination source. I was able to find a Source Water Assessment Summary for The Pennsylvania State University  from 2003 on the public water system. After reading over it, I found that the source of water for Penn State is composed of nine wells in two well fields located in Big Hollow and Houserville. The water is treated with chlorine at a treatment building before it goes to the distribution center. The summary includes a list of possible contamination sources, but most are common and possible threats to any water source. Ongoing protection activities for watersheds is included, as well as protection needs. I was unable to find a more recent survey, but from this summary, I was unable to see any direct harmful threats as a result from drinking the tap water. There seems to be no more risk drinking out of the faucets here at PSU than there is drinking from tap water at home.

In conclusion, should my roommate stop using her Brita filter, is it necessary, or should she drink tap water? This reminds me of a question that was on a pop quiz earlier this year that asked: “As described, is the study design good enough to provide data that would cause you to alter your bathroom behavior?” The question had an asterisk because it was more of a personal opinion, which I feel is the case for this Brita question. I personally do not see a huge problem with drinking the tap water, and the Brita could most likely be adding more bacteria. It would have to be up to her to decide what matters most to her, that being taking the chance of extra bacteria or having water that maybe tastes better because of the filter.

Sources:

http://www.ncbi.nlm.nih.gov/pubmed/8740859

http://waterindustry.org/Water-Facts/filtered-1.htm

Click to access RW4140095001%20Penn%20State%20Univ%20–%20Univ%20Park.pdf