[Pharmwaste] Natural, Synthetic Endocrine Disruptors Pass From Septic Tank to Groundwater

[DeBiasi,Deborah]

The text to this article was 'scrubbed' in the previous email - I'll try again


BNA, Inc.  
Environment Reporter

Volume 37 Number 32 
Friday, August 11, 2006
 					Page 1677 
 
ISSN 1521-9410
 
Water Pollution
 
Drinking Water

Natural, Synthetic Endocrine Disruptors
Pass From Septic Tank to Groundwater
By Pat Phibbs-Rizzuto 

Natural and synthetic endocrine-disrupting chemicals can pass through septic systems and reach groundwater, according to a study that will appear in the Aug. 15 print issue of Environmental Science & Technology, the American Chemical Society's journal. 

While groundwater studies have been conducted in regions where septic tanks are believed to be the source of water pollution, this is the first study to specifically track natural estrogen, synthetic estrogenic chemicals such as nonylphenol, and other organic wastewater contaminants, from a specific septic tank through the soil and into groundwater, lead author Christopher H. Swartz told BNA Aug. 8. 

Swartz works with the Silent Spring Institute and the Stockholm Environment Institute, research organizations focused on environmental issues. 

"I was surprised that natural estrogen traveled as far as it did," he said. The research team measured a type of estrogen in groundwater up to 25 feet from the septic tank. 


Pollutants Crossing Property Lines

A distance of 25 feet means "you may be pretty much crossing over the property line and into your neighbor's property," Swartz said. 

Organic wastewater contaminants, such as those Swartz studied, have been detected in private drinking water wells on Cape Cod, where this study took place. 

The study was conducted on Cape Cod because more than 85 percent of residents and commercial properties use septic systems, he said. 

As a result of the cape's housing boom, widespread use of septic systems, and the shallow groundwater aquifer that is used for drinking water on the cape, scientists have become increasingly concerned about wastewater contamination of the cape's drinking water supply, Swartz said. 

Previously, researchers have studied the extent to which nitrogen and phosphorus could be transferred from septic systems to groundwater, Swartz said. 

But his research team wondered if other chemicals, including hormone disruptors, might be transferred along with the nitrogen and phosphorus. Hormone disruptors are chemicals that mimic, block, or alter the function of normal hormones. This study focused on natural estrogen and synthetic estrogen-like chemicals. 

Estrogenic compounds have feminized male fish by making them release a protein that normally is excreted by female fish, the Silent Spring Institute said in a news release publicizing its study. While it is not known whether the environmental concentrations of hormone-disrupting chemicals would harm human health, some scientists are concerned about the chemicals' potential to cause harm especially when exposure occurs during critical prenatal and childhood reproductive development, the release said. 

Swartz said his team found a type of estrogen in groundwater at concentrations similar to levels that have feminized male fish in other studies. 

More research is needed to know whether other types of septic tanks located in other geological settings would also leach wastewater contaminants into groundwater, Swartz said. 

"I hope the study's results will get people to start thinking about long-term sustainability of on-site sewage treatment," he said. 

It is important, for example, to provide as great a distance as possible from groundwater to the leachate pits that collect overflow water from septic tanks, he said. 

Leachate pits also should not be overloaded, lest the amount of waste overwhelm the bacteria that break it down, Swartz said. 


Modeling Effects to Identify Sources

A second study, published Aug. 3 in the online version of Environmental Science & Technology, also deals with endocrine-disrupting compounds. 

A team of British researchers, led by John P. Sumpter from Brunel University's Institute for the Environment, discuss a method regulatory authorities could use to identify sewage treatment works with the greatest likelihood to release endocrine-disrupting chemicals at levels that would harm aquatic organisms. 

The British research team used the Geography-referenced Regional Exposure Assessment Tool for European Rivers (GREAT-ER) hydrological model to predict concentrations of estrogen and other estrogenic chemicals, including nonylphenol, throughout an entire river catchment area. 

By using this method to identify where effects would be most likely to occur, regulators could target sewage treatment works predicted to have the most severe effects on aquatic organisms, the study said. 

"This would produce the most rapid improvement in the quality of the aquatic environment," the study said. 

The first study, Steroid Estrogens, Nonylphenol Ethoxylate Metabolites, and Other Wastewater Contaminants in Groundwater Affected by a Residential Septic System on Cape Cod, can be purchased at http://pubs.acs.org/cgi-bin/abstract.cgi/esthag/asap/abs/es052595+.html. 

The second study, Modeling Effects of Mixtures of Endocrine Disrupting Chemicals at the River Catchment Scale, can be purchased at http://pubs.acs.org/cgi-bin/abstract.cgi/esthag/asap/abs/es052554d.html. 

By Pat Phibbs-Rizzuto

 

 


Deborah L. DeBiasi
Email:   dldebiasi at deq.virginia.gov
WEB site address:  www.deq.virginia.gov
Virginia Department of Environmental Quality
Office of Water Permit Programs
Industrial Pretreatment/Toxics Management Program
Mail:          P.O. Box 10009, Richmond, VA  23240-0009 
Location:  629 E. Main Street, Richmond, VA  23219
PH:  	804-698-4028
FAX: 	804-698-4032