AUDUBON, Iowa (AP)--Farm wife Sharlene Merk is encouraged by research findings that a cocktail of ground horseradish and hydrogen peroxide can cut the stench of hog manure.

From the door of her rural farmhouse in southwest Iowa, Merk can see two long blue buildings containing thousands of hogs on a neighboring farm. A second hog farm, with thousands more animals crammed into three white buildings, is less than half a mile away.

The 67-year-old Merk said the stink often makes her and her husband Leroy, 71, feel physically ill.

"A lot of times we simply have to leave home because it is so bad," she said.

When mixed with a manure slurry, the horseradish cocktail neutralizes the chemical compounds that comprise odor--substances called phenols, said Jerzy Dec, a senior research associate at Pennsylvania State University.

Dec said the horseradish mixture cut odor intensity as much as 50 percent--at least that's what the six people on the test panel said after sniffing the hog slurry, obtained from a university research farm.

The findings were confirmed through gas chromatography, which documents the chemical makeup of the air. It confirmed that 100 percent of odor-causing chemicals were neutralized for at least 72 hours.

"At least you have three days to go and dispose of your treated manure," Dec said.

The study, which appeared in the June 29 issue of the Journal of Agricultural and Food Chemistry, emerged from previous research that found that minced horseradish roots, potato tubers and white radish roots, combined with small amounts of hydrogen peroxide, removed phenols, including industrial contaminants, from water and soil.

Dec said the horseradish works because it contains large quantities of an enzyme that breaks down the phenols, which are formed from sugars.

The horseradish mixture is environmentally friendly and can be reused up to six times before having to be replaced, making it a cost-efficient option for farmers.

Horseradish prices are a little high, but "if this method catches on then the prices should drop dramatically," Dec said.

Dec said the discovery is important as factory farms continue to spread in Iowa, where hogs outnumber people 5-to-1, and in other rural states across the nation. Such factory operations, which can house thousands of animals under one roof, produce tons of manure, often stored onsite in pits and lagoons.

The stench from such farms has caused neighbors to launch legal battles against them and industry experts worry that it could halt the growth of livestock enterprises.

Dec said he would like to perform larger tests with the horseradish mixture and he hopes the $40 billion pork industry will dedicate more money toward research of odor control.

Leon Sheets, 52, who operates a 1,200 head farrow to finish hog farm near Ionia, said there is much work being done on the topic.

"We're using some existing technology, some natural things already," he said. "This will just be further enhancement as pork producers try to just be more community friendly."

Other attempts at odor control include a recent study at Purdue University, where scientists are tinkering with the ingredients of hog feed. University of Iowa researchers said they developed a system that would reduce odor by bombarding manure with ultrasound, but the process to get a patent has stalled.

That there are existing production facilities for horseradish makes it an attractive option, Sheets said.

"With an existing product this has to be good if the combination of products are determined that it really works," he said.

Merk said she would much prefer the smell of horseradish to that of hog slurry.

"I think we could take that a heck of a lot better than the other," she said, chuckling.

Date: 7/21/05