Only after the last tree has been cut down.  Only after the last river has been poisoned.  Only after the last fish has been caught.  Only then will you find that money cannot be eaten.

"When an activity raises threats of harm to human health or the environment, precautionary measures should be taken even if some cause and effect relationships are not fully established scientifically. In this context the proponent of an activity, rather than the public, should bear the burden of proof." - Wingspread Statement of the Precautionary Principle.
Study Shows Factory Farms Lower Neighboring Homes’ Property Values
Money losses add to health, fly, fume, water quality and traffic problems

Posted July 31, 2003, Gettysburg, PA: Citizens for Pennsylvania’s Future (PennFuture) cited a Penn State University study released (June 6) which showed that home owners in Berks County (PA) are better off living near a sewage treatment plant than a factory farm when it comes to the value of their property.

“A nearby factory farm lowers a family’s property values by more than $1,800,” said Jan Jarrett, PennFuture’s director of Outreach. “This is on top of the problem with flies, dangerous fumes, water contamination and traffic that families must endure when one of these industrial animal factories opens. However, this same land, when used as a traditional farm, actually increases property values.

The study, summarized in the report "The Impact of Open Space and Potential Local Disamenities on Residential Property Values in Berks County, Pennsylvania," was authored by Richard Ready, assistant professor of agricultural and environmental economics, and Charles Abdalla, associate professor of agricultural and environmental economics at Penn State's College of Agricultural Sciences.

The study found that open space — including forested acreage and grass, pasture and cropland — located within a quarter-mile of a house had the largest positive effect on the value of that house. The researchers also found that landfills and large-scale animal operations have negative influences on nearby house prices. The complete study is available online at http://www.landuse.aers.psu.edu