The Fate of Hormones in the Aquatic
Environment
Figure 1: Examples of hormones present in the aquatic environment effluent.
Starting in the early 1990s, researchers began reporting feminization
of male fish (e.g., the presence of egg proteins in their blood).
In rivers that received significant inputs of municipal wastewater
effluent, the feminization of male fish was found to be attributable to
the presence of steroid hormones, such as 17beta-estradiol, ethinyl
estradiol and estrone (Figure 1). Over the past decade, our
research group has developed analytical methods for quantifying the
extremely low concentrations of steroid hormones present in the aquatic
environment (e.g., certain species of fish can be feminized by exposure
to steroid hormones at concentrations as low as 1 ng/L). We also
have studied the fate and transport of these compounds and more
recently have begun to study sources of steroid hormones unrelated to
municipal wastewater.
As we learned in the initial phase of our research (Huang et al. 2001),
the concentrations of steroid hormones in municipal wastewater effluent
usually are high enough to induce feminization of fish. In some
cases, the concentrations also are high enough to interfere with
chemical communication among fish, which is crucial to successful
reproduction (Kolodziej et al. 2003). While it may be possible to
reduce the concentrations of steroid hormones to levels that do not
pose a risk by applying advanced treatment methods, such as reverse
osmosis, most utilities are reluctant to invest in such expensive
treatment systems. Engineered treatment wetlands provide a
potentially cost-effective approach for reducing the concentrations of
steroid hormones. Doctoral research conducted by James Gray (Gray
and Sedlak 2005) demonstrated the partial removal of steroid hormones
in an engineered wetland located near Los Angeles (Figure 2).
However, the removal was incomplete and additional research is needed
to quantify the roles of sorption, biotransformation and photolysis in
the removal process.
Figure 2: Engineered Treatment Wetlands.
More recently, we have
begun to turn our attention to sources of steroid hormones unrelated to
wastewater effluent. For example, as part of his doctoral
research, Ed Kolodziej showed that runoff from dairy farms and effluent
from aquaculture facilities both contain measurable quantities of
steroid hormones (Kolodziej et al. 2004). More recently, we have
found elevated concentrations of steroid hormones in watersheds where
grazing cattle have access to streams. We are currently studying
the potential impacts of steroid hormones and other
endocrine-disrupting compounds in California's Central Valley in
collaboration with Professor Daniel Schlenk
(UC Riverside) and Dr. Robert Spies (Applied Marine Sciences).
For more information see:
Gray J.L. and Sedlak D.L. (2005) The fate of
estrogenic hormones in an engineered treatment wetland with dense
macrophytes. Water Environ. Res.,77, 24-31.
Huang, C.H. and Sedlak, D.L. (2001) Analysis of estrogenic hormones in
municipal wastewater effluent and surface water using ELISA and
GC/MS/MS. Environmental Toxicology and Chemistry, 20, 133-139.
Kolodziej E.P., Harter T. and Sedlak D.L. (2004)
Dairy wastewater, aquaculture and spawning fish as sources of steroid
hormones in the aquatic environment. Environ. Sci. Technol., 38,
6377-6384.
Kolodziej E.P., Gray J.L. and Sedlak D.L. (2003)
Quantification of steroid hormones with pheromonal properties in
municipal wastewater effluent. Environmental Toxicology and Chemistry,
22, 2622-2629.
|
|
The Fate of Hormones in the Aquatic Environment
Pharmaceutically-Active
Compounds in Aquatic Systems
Formation
and Removal of NDMA in Water Recycling Systems
Oxidation of Contaminants by Iron Nanoparticles in the Presence of Oxygen
|
