[USCC] Use of Composted Manure on Food Crops

[McNelly, Patrick]

The following article by Dennis Avery was picked up today in the Orange
County Register, and I'm sure that is has appeared elsewhere recently.
I'd be interested in the opinions of other members of this list on this
topic.  Avery has a long history of opposing using composted organics in
agriculture.  I can't vouch for the veracity of anything he says here,
but I suspect he hasn't gotten all of his facts straight.

 

Some good commentary on this issue can also be read on Grist -
Environmental News and Commentary:

 

http://gristmill.grist.org/story/2006/9/15/232913/864

 

 

Tainted Spinach Raises Questions of Manure on Food Crops

 

 

Ten years after one of the country's top food safety experts warned of
danger from putting manure on food crops, Americans are still being
devastated by manure-born pathogens. It doesn't have to be. 

 

Contaminated raw spinach has just killed at least one person, brought
devastating kidney failure to 23, hospitalized more than 75, and
sickened more than 150 people across America. The deadly spinach has
been traced back to Natural Selections Foods, the largest grower of
organic lettuce and spinach in the United States. 

 

Organic rules bar the use of manufactured fertilizer on their crops, so
organics use composted manure and other animal wastes on their fields.
Animal manure is the ultimate source of the virulent E. coli O157:H7,
which contaminated the spinach. 

 

In 1995, the Journal of the American Medical Association quoted Dr.
Robert Tauxe, head of food borne illnesses for the U.S. Centers for
Disease Control, telling a medical conference that "'Organic' means a
food is grown in animal manure. . . . We got rid of human waste in our
food and water, and I think we're going to have better control in the
future of manure in our food and water." 

 

The Organic Trade Association responded that organic food was safe
because farmers compost their manure. Dr. Tauxe responded that
"Unfortunately, knowledge of the critical times and temperatures needed
to make composted animal manures microbiologically safe is incomplete." 

 

Today, USDA organic rules allow manure to be applied after just 3 days
of composting-right up to harvest time! Raw manure can be applied until
90 to 120 days prior to harvest, under most state-level rules for all
farms. But a recent University of Minnesota study found that produce
grown with manure aged 6 to 12 months was still 19 times more likely to
be contaminated with E. coli than foods grown with manure aged more than
a year. 

 

Virtually no farmers age their manure for a year as too much of the
vital nitrogen gasses off into the air during that time. Instead, most
conventional farmers put their manure only on feed crops such as corn or
on pasture. That may be why the Minnesota researchers found organic
produce three times more likely to be contaminated with E. coli (7% of
samples) than conventional (2%). 

 

Organic activists love to claim that the deadly O157:H7 strain of E.
coli is caused by "factory farming." Not so. The USDA says it has found
O157:H7 in every cattle herd it's tested for it. A Swiss study last year
found "no significant differences" in O157:H7 prevalence between organic
and conventional dairy farms. Claims that "grain feeding" of cattle
causes O157:H7 to flourish are also unsupported; various studies have
found the opposite. 

 

Washing the food can't fully protect consumers either. Rutgers
University has shown that lettuce (and likely spinach) can take up
O157:H7 via its roots and harbor the pathogens inside the leaves! In
short, there is no practical way to ensure full safety in the food crops
fertilized with manure, composted or not. 

 

Is it time to get the manure out of human food crops? 

 

States could require that manure either be used on non-food crops or
composted for at least a year. Annual questionnaires could identify the
relatively few farms that compost with regular government inspections
made.

 

This will raise howls of protest from the organic movement, which also
protested the current weak manure rules. However, it's now clear that
using manure on food crops involves a serious public risk-especially
with leafy produce like lettuce and spinach. The organic movement should
want to ensure its customers health as urgently as do public health
officials. 

 

Eating no longer needs to be a deadly game of Russian roulette. 

 

 

Dennis T. Avery 

 

Director, Global Food Issues