Making modern manure

Tasty manure solution? (carbonated!)
POSTED 24 AUG 2001

RELATED
WHY FILES:
Urine to the rescue

Beef, Hormones and GMOs

Downwinders beware: farm-fresh fertilizer is stored in a "lagoon," AKA "pond."
Courtesy Penn State's Instructional Resource Server

bubbles

At a cost of $10 per cow per year, carbonate treatment could reduce threats to human health.

Livestock make about 100 billion kilograms of manure in the United States each year, and most of it is spread on farm fields. Downwinders beware: farm-fresh fertilizer is stored in a 'lagoon,' AKA 'pond.'

Downwinders beware: farm-fresh fertilizer is stored in a 'lagoon,' AKA 'pond.'

Manure contains plenty of pathogens, but according to conventional wisdom, those disease-causing microbes are held by soil particles. They do not run off to streams or percolate to the groundwater.

Today, as huge livestock farms raise thousands of head of livestock at factory farms, manure disposal problems are multiplying. Unfortunately, the assumption that current manure-disposal practices are safe has recently been hit with a triple whammy:

In Walkerton, Ontario, seven people died and hundreds got sick in May, 2000, after cattle manure carrying a deadly strain of E coli (O157:H7) washed into a municipal well.
In 1996, a survey by the Environmental Protection Agency found that 40 percent of rural wells were contaminated with E coli. Although most strains are harmless, E coli marks fecal contamination of water.
Tests at Cornell University showed that E coli can migrate through soil to the groundwater.

Today, it seems that bacterial pathogens can also infect surface water, and vegetables that are either grown with or washed in that water, says James Russell, a researcher with the Agricultural Research Service of the U.S. Department of Agriculture in Ithaca, NY.

Russell sees trouble -- not just fetid vapors -- bubbling up from the giant manure pits and lagoons where farmers store animal waste.

He wondered: Could manure be disinfected safely and cheaply?

a metal pipe pointed into the 'lagoon'

The answer was as close as the stream of urine from the back of a dairy cow. For years, Russell says, scientists have known cow urine kills microbes in cow manure.

Dairy Research and Education Center, Purdue University

A few tests told Russell this only happened if the mixture contained at least as much urine as feces. Tragically, cows make too little urine -- the average American cow makes about 40,000 kilograms of manure -- and less than half that stunning quantity of urine.

Even non-farmers know urine contains plenty of ammonia, which, according to conventional wisdom, was the microbe killer.

Although Russell's tests disproved this notion, he observed that the chemical reaction that makes ammonia (urine's urease reacts with urea -- repeat three times, please) also produces an ion, or molecular fragment, called carbonate. And carbonate ion turns out to be the bacteria blaster.

In lab tests, Russell found that added carbonate would compensate for the shortage of urine-borne carbonate. After five days' treatment, E coli could not be found in samples that, before treatment, contained 100,000 to 100 million units of E coli.

As near as Russell can make out, carbonate kills the bacteria by reacting with magnesium ions to make magnesium carbonate. This "rock," as Russell calls it, removes necessary magnesium, and the bacteria die.

So carbonated cow manure could be a health drink for the landscape.

But the implications could extend beyond the barnyard. "Carbonate appears to have a relatively broad-spectrum ability to kill Listeria, Salmonella, a variety of pathogens," says Russell. "That's a new finding."

In other words, carbonate treatment could become an affordable weapon against nasties in other filthy wastes.

bubbles Selling carbonated cow manure
Some day. Russell's experiments were done in the lab, not on the farm. Although he says it should cost as little as $10 per cow per year, it's uncertain whether farmers will bother unless pressed by regulators.

Things may start slowly, Russell indicates, noting that the technique might be adopted first at large farms, especially those located in sensitive areas that feed municipal drinking-water systems.

-- David Tenenbaum

BIBLIOGRAPHY
Use of Carbonate and Alkali to Eliminate Escherichia coli from Dairy Cattle Manure, Francisco Diez-Gonzalez et al, Environmental Science and Technology, 2000, 34, 1275-1279.

POSTED 24 AUG 2001
	RELATED WHY FILES: Urine to the rescue Beef, Hormones and GMOs Fossil Feces Inventing Agriculture Filtering Pollution Countless bacteria Downwinders beware: farm-fresh fertilizer is stored in a "lagoon," AKA "pond." Courtesy Penn State's Instructional Resource Server	Livestock make about 100 billion kilograms of manure in the United States each year, and most of it is spread on farm fields. Manure contains plenty of pathogens, but according to conventional wisdom, those disease-causing microbes are held by soil particles. They do not run off to streams or percolate to the groundwater. Today, as huge livestock farms raise thousands of head of livestock at factory farms, manure disposal problems are multiplying. Unfortunately, the assumption that current manure-disposal practices are safe has recently been hit with a triple whammy: In Walkerton, Ontario, seven people died and hundreds got sick in May, 2000, after cattle manure carrying a deadly strain of E coli (O157:H7) washed into a municipal well. In 1996, a survey by the Environmental Protection Agency found that 40 percent of rural wells were contaminated with E coli. Although most strains are harmless, E coli marks fecal contamination of water. Tests at Cornell University showed that E coli can migrate through soil to the groundwater. Meet Poopsi Cola Today, it seems that bacterial pathogens can also infect surface water, and vegetables that are either grown with or washed in that water, says James Russell, a researcher with the Agricultural Research Service of the U.S. Department of Agriculture in Ithaca, NY. Russell sees trouble -- not just fetid vapors -- bubbling up from the giant manure pits and lagoons where farmers store animal waste. He wondered: Could manure be disinfected safely and cheaply? The answer was as close as the stream of urine from the back of a dairy cow. For years, Russell says, scientists have known cow urine kills microbes in cow manure. Dairy Research and Education Center, Purdue University A few tests told Russell this only happened if the mixture contained at least as much urine as feces. Tragically, cows make too little urine -- the average American cow makes about 40,000 kilograms of manure -- and less than half that stunning quantity of urine. Even non-farmers know urine contains plenty of ammonia, which, according to conventional wisdom, was the microbe killer. Although Russell's tests disproved this notion, he observed that the chemical reaction that makes ammonia (urine's urease reacts with urea -- repeat three times, please) also produces an ion, or molecular fragment, called carbonate. And carbonate ion turns out to be the bacteria blaster. In lab tests, Russell found that added carbonate would compensate for the shortage of urine-borne carbonate. After five days' treatment, E coli could not be found in samples that, before treatment, contained 100,000 to 100 million units of E coli. Bye-bye bug As near as Russell can make out, carbonate kills the bacteria by reacting with magnesium ions to make magnesium carbonate. This "rock," as Russell calls it, removes necessary magnesium, and the bacteria die. So carbonated cow manure could be a health drink for the landscape. But the implications could extend beyond the barnyard. "Carbonate appears to have a relatively broad-spectrum ability to kill Listeria, Salmonella, a variety of pathogens," says Russell. "That's a new finding." In other words, carbonate treatment could become an affordable weapon against nasties in other filthy wastes. Selling carbonated cow manure Some day. Russell's experiments were done in the lab, not on the farm. Although he says it should cost as little as $10 per cow per year, it's uncertain whether farmers will bother unless pressed by regulators. Things may start slowly, Russell indicates, noting that the technique might be adopted first at large farms, especially those located in sensitive areas that feed municipal drinking-water systems. -- David Tenenbaum
		BIBLIOGRAPHY Use of Carbonate and Alkali to Eliminate Escherichia coli from Dairy Cattle Manure, Francisco Diez-Gonzalez et al, Environmental Science and Technology, 2000, 34, 1275-1279.
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