Just how dirty have our coasts become?
The Providence Journal
By Patricia Holden
January 16, 2000
People naturally want to live near the ocean. Thats
one reason why California, Florida, and the Carolinas are among the
nations fastest-growing states. Unfortunately, more people means
more human waste. In turn, this means that more human waste finds its
way into the water along those coastlines.
At least, that is what we think. But, in reality,
we dont know how healthy or diseased our beaches are because the
testing that government agencies conduct to monitor those beaches is
not nearly sophisticated enough. Our beaches may be very safe. Or they
may be health hazards. No agency can yet say which is true.
It is hard for any agency to know just how sick people could become from recreating along the coastlines around the United States, or if theyre getting sick at all. Some swimmers, surfers, and fishermen voluntarily take crude precautions- that is, they avoid the beaches that are near the creek mouths and sewer outfalls. These precautions, i.e., the "ounce of prevention", could be a "cure" for protecting swimmers. But, since there are so very few epidemiological studies of how sick swimmers become in our coastal waters, and few facts about the levels of contamination, its a tough sell for public health agencies to broadly recommend when or where not to swim, surf, or fish.
The reason that the health of our beaches is in question
is that the testing methods used and required by government agencies
dont directly detect pathogens in the coastal waters around the
United States. (A pathogen is either bacteria or virus that can cause
disease, usually respiratory infection, gastrointestinal ailments, and
ear and eye infections.) Heres how coastal water in the United
States is monitored.
Agencies test what are called "indicator organisms,"
jargon for microbes that are only indicative of the presence of human
waste in the environment- proxies for human waste microbes. Based on
these "proxy" tests, agencies may post a warning to those
using the beach. Every year some big beach is closed because results
of the test show high levels of "indicator organisms." While
indicator organisms are good yet conservative methods for protecting
drinking water, they throw off false negative and false positive readings
in storm water, creeks, and oceans. This is because indicator organisms
may be found in soil, in creek waters or in animal waste. So it is tough
to know if there are organisms in the ocean that could really make people
In short, indicator organisms are not a good way to
test for pathogens in environmental waters. We need improvements that
will give the public greater assurance as to the safety of beaches and
*Augment current monitoring (i.e., indicator organisms)
with tests that more accurately measure the presence of pathogens, or
the presence of human waste. These tests would involve greater use of
molecular biology. Unfortunately, most public agencies dont yet
have these tools. But perhaps the use of chemical markers for human
waste can be used as a temporary solution until better testing is developed.
*Improve our data base for the illness rate for swimmers,
surfers and fishermen who use these coastlines. If we could have a more
comprehensive database of who gets sick, the frequency of the illnesses,
and what type of illness, then wed have a better understanding
of how contaminated shorelines are.
*Develop a more systematic way of detecting human-waste
sources. We need to know whats going on in what are called "black
boxes," septic systems and old sanitary sewers that have been around
for a long time. Residential septic systems are all over the country
and they have been seen as a proper way of waste disposal, but we dont
yet understand how each field functions, and how much septic systems
could be contributing to shoreline contamination.
*Greater coordination among groups conducting research
on shoreline contamination around the United States. As with law enforcement
agencies, people are surprised by the lack of communication between
scientific groups. By using the Internet, agencies can gather more information
about what other groups are doing to monitor shoreline water, and can
gather the latest research on water contamination.
Our beaches are national treasures. As populations increase along our shores, there is an even greater need to produce more sophisticated tracking, testing, and monitoring. Not only for our own recreational use, but for those who depend on the oceans for other reasons as well.
Patricia Holden is an assistant professor of environmental microbiology at the Bren School of Environmental Science & Management at the University of California at Santa Barbara.