Volume 6, Spring 2008 - Saddleback College

Fall 2007 Biology 3A Abstracts
environmental conditions for one week. Then aggression levels were once again measured.
There was not a significant difference in aggression responses between the pre- and postexposure
to ethinyl estradiol.
Introduction
Pharmaceutical drugs in water supplies
Pharmaceuticals, household chemicals, and
biogenic hormones are released directly into the
environment after passing through wastewater
treatment processes, which are often not designed to
completely remove these chemicals from the effluent.
Many of these chemicals are in streams throughout the
United States, including antibiotics, various
prescription drugs, nonprescription drugs, steroids,
reproductive hormones, personal care products, and
other extensively used chemicals (Kolpin et al., 2002).
Thus, the extent of pharmaceutical and personal care
products (PPCPs) in the aquatic environment and their
consequences are beginning to be monitored by some
scientists (Potera, 2000).
U.S. Geological Survey personnel tested a
total of 139 streams; Table 1 lists the prescription drugs
that were found and the respective concentrations
(Kolpin et al., 2002). This list contains drugs that are
used for a variety of different conditions in the human
body. According to Christian Daughton, chief of the
Environmental Chemistry Branch of the U.S.
Environmental Protection Agency (EPA)
Environmental Sciences Division in Las Vegas,
Nevada, researchers worldwide have discovered more
than sixty different PPCPs in water sources (Potera,
2000).
Table 1. List of some prescription drugs detected in
streams across the United States (from Koplin et al.,
2002, pg 1204)
Chemical N RL Feq (%) Max Median
Albuterol 84 0.029 0 ND ND
Cimetidine 84 0.007 9.5 0.58 0.074
Codeine 84 0.1 10.4 1 0.2
Digoxin 46 0.28 0 ND ND
Dilitiazem 84 0.012 13.1 0.49 0.21
Fluoxetine 84 0.018 1.2 0.012 0.012
Gemfibrozil 84 0.015 3.6 0.79 0.048
Metfibrozil 84 0.03 4.8 0.15 0.11
Paroxetine 84 0.26 0 ND ND
HCL
Rantidine 84 0.01 1.2 0.01 0.01
Warfarin 84 0.001 0 ND ND
Environmental engineer Pierre Labadie and
his students at the University of Sussex obtained water
samples from the Ouse River at two sites: Ditchling
(200 m downstream) and Lewes (500 m downstream).
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Saddleback Journal of Biology
Spring 2008
Varying concentrations of levels of estrogen were
detectable in both the depth profiles of Ditchling and
Lewes. Average estrogen concentrations in the water
column at the Ditchling site, during the month of
December, were predicted to be among the highest,
whereas, at Lewes, no subsurface peak was observed,
and estrogenic activity declined with increasing
sediment depth (Labadie et al., 2007).
It should be noted that estrogen was targeted
for this experiment due to the potential of interfering
with normal reproduction and development in fish
living downstream from sewage plants. Little
information is known about the effects of
environmental occurrence, transport, and ultimate fate
of many pharmaceuticals that are designed to stimulate
a physiological response in humans and animals
(Kolpin et al., 2002).
Effects of estrogen on humans
Approximately 39% of women today are
taking some kind of birth control method. Birth control
pills, also called “the Pill”, are typically prescribed to
patients to change the way the body works and prevent
pregnancy.
Hormones are chemical substances that
control the functioning of the body’s organs. Most birth
control pills, or "combination pills", contain a
combination of the hormones estrogen and
progesterone to prevent ovulation (the release of an egg
during the monthly cycle). A woman avoids pregnancy
by not ovulating. One hormone pill is taken orally
each day, in the form of tablets, at about the same time
for 21 days.
In some cases, the effects of hormones on
behavior depend on the environment. Estrogens can
affect physiology and behavior through two general
pathways. It can alter the activity of neural cells by
genomic action. When estrogen binds to a classical
estrogen receptor in the cytoplasm, it enters the nucleus
and changes gene expression (which ultimately leads to
changes in proteins). This is why it is often necessary
to wait several days or weeks for effects of hormone
manipulations to occur (Kolpin et al., 2002).
As a sex hormone, estradiol is present in both
females and males. It not only has a critical impact on
reproductive and sexual functioning but also other
organs, including bone structure.
Effects of estrogen on aquatic animals