Introduction
With the ever
increasing range and use of pharmaceuticals, anti-biotics, and birth control
among the American population the levels of these chemicals are likewise
increasing in the water supply. The intentional and unintentional disposal of
these chemicals all leads to their place in the sewer system. According to a national
survey done by the Associated Press, many water distributing companies across
the U.S. don’t even test for these chemicals, and they are being found in our
drinking water (1). The effect of these chemicals in the water supply is
somewhat researched, but widely unknown in most cases (2, 3). This makes
necessary more research on the effects of chemicals in the water supply not
only on fish, but also on other organisms such as bacteria, fruit flies, and
even humans.
There are two mains
sources of pharmaceuticals in our water supply. One is their consumption by humans
for medical reasons. After the body processes these chemicals they are excreted
and end up in the sewer system. Another major source is from the agricultural
industry and animal farming. Several anti-biotics and hormones are used in
agriculture and animal farming, and these chemicals also end up in the sewer
system (4).
The USGS stated before
congress that the presence of the aforementioned chemicals in the water supply
is a cause for concern and recommends more research in this area (5). In a different
study, the USGS expressed a concern for interactions between pharmaceuticals in
the public water supply (6). They found evidence to suggest that the
interactions between these chemicals are capable of disrupting the endocrine
system in organisms such as fish (6). Even though the physiological effects of
these chemicals are widely unknown, there is research that suggests that low
doses of drugs such as anti-biotics, hormones, and waste products such as
bisphenol-A can cause serious effects over an extended period of time.
Goal
1: Water Collection
First,
we would need to collect water samples from various cities around the state of
Alabama. We will collect water samples from before and after the city’s water
treatment plant in order to see which chemicals they are effectively filtering
out and what remains in the public water supply. Samples will be taken from
cities such as: Marion, Birmingham, Tuscaloosa, Mobile, and Montgomery. In
addition, we will also take samples from the natural waterways including: the Cahaba
River, Alabama River, Lake Tuscaloosa, etc. Taking samples at the major run-off
points and then approximately one mile downstream will help us measure how
effectively the chemicals used in agricultural farming are diluted through
natural cleaning mechanisms.
Goal
2: Identification of pharmaceuticals present
The
next step in our research is to identify which chemicals are present. To do
this will analyze the water samples using mass spectrometry. This method will
be accurate and sensitive to the chemicals we are looking for (anti-biotics, sex
hormones, industrial chemicals, etc.), even at low concentrations.
Goal
3: Toxicological effects in model organisms
Once
we know which chemicals are present in the public water supply and the natural
waterways, we will conduct various experiments with model organisms to
determine their toxicological effects. In order to determine the effects of
these chemicals on the environment, we will conduct a series of dosage
experiments on zebrafish (D. rerio),
bacteria (E. coli), and fruit flies (D. melanogaster), three species that are
often used as models to study the effects of chemicals on living things. We are
interested to see how these chemicals affect these organisms both at high doses
over short periods of time and at low doses over long periods of time.
zebrafish (D. rerio)
bacteria (E. coli)
fruit flies (D. melanogaster)
References
(1)
Goodman, A. (2008) Sedatives and Sex Hormones in
Our Water Supply. Associated Press. http://www.alternet.org/water/80505/?page=1
(2)
Schreck, C. (2007) Endocrine Disruption:
Sex-Changing Fish and More. Unitied States Geological Survey. http://gallery.usgs.gov/audios/3
(3)
Collier, R. (2012) Swallowing the pharmaceutical
waters. Canadian Medical Association Journal. http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3273502/?tool=pmcentrez
(4)
Bartekt-Hunt, S., Snow, D.D., Damon-Powell, T.,
Miesbach, D. (2011) Occurrence of steroid hormones and antibiotics in shallow
groundwater impacted by livestock waste control facilities. Journal Contaminant
Hydrology
(5)
Hirsch, R.M. (2008) Congressional statement made
by the Associate Director for Water (Dr. Robert M. Hirsch) at the USGS before
the Committee on Environment and Public Works.
(6)
Barber, L.B., Murphy, S.F., Verplanck, P.L.,
Sandstrom, M.W., Taylor, H.E., and Furlong, E.T. (2006) Chemical loading into
surface water along a hydrological, biogeochemical, and land use gradient—A
holistic watershed approach. Environmental Science and Technology, v. 40, no.
2, p. 475-486.
