What is E. coli?
E. coli (Escherichia coli) are bacteria that normally live in the intestines of animals, including humans. In fact, the presence of E. coli and other kinds of bacteria within our intestines is necessary to help the human body develop properly and to remain healthy (see web site: http://www-micro.msb.le.ac.uk/video/Ecoli.html). There are approximately 100 strains of E. coli, most of which are beneficial.
Are all E. coli equal?
No. Although E. coli inhabit the intestinal tract as beneficial microorganisms, there also are strains of E. coli that are known to produce toxins. Four such strains have been identified. The National Center for Infectious Diseases, Centers for Disease Control and Prevention (CDC), particularly warns of the dangers posed by the rare strain E. coli O157:H7, a pathogenic strain isolated from manure from cattle, sheep, pigs, deer and poultry. This strain can cause severe diarrhea and kidney damage and sometimes death. Young children, the elderly, and those with weakened immune systems are the most vulnerable.
The current outbreak originating in Germany is linked to a new strain, E. coli 0104:H4, which has never been seen in an outbreak before. This new strain appears to be highly infectious and toxic, but little else is known about it thus far. What is known is information about the 0157:H7 strain, which has been linked to outbreaks in the past.
How does E. coli O157:H7 get into food?
Statistics from CDC show that a vast majority of food-borne disease is associated with cross-contamination and handling later in the distribution chain and in the home. According to the CDC, most illness from E. coli O157:H7 has been associated with eating undercooked, contaminated ground beef. In recent years, E. coli O157:H7 has been identified in outbreaks of foodborne illness linked to fresh produce.
The bacteria live in the intestines of some healthy cattle, and contamination of the meat may occur in the slaughtering process. Eating meat that is rare or inadequately cooked is the most common way of possible exposure to E. coli O157:H7 contamination. Person-to-person transmission also can occur if infected people do not adequately wash their hands. Produce may become contaminated by pathogenic E. coli due to exposure to contaminated water, improper use of manure, or improper handling at the plant, in transport, at the retailer, or in the home.
Are organic products more likely to be contaminated by E. coli?
No, there is no evidence to indicate this. All food—whether conventional or organic—is susceptible to E. coli. In fact, CDC has issued the following statement: “The Centers for Disease Control and Prevention…has not conducted any study that compares or quantitates the specific risk for infection with Escherichia coli O157:H7 and eating either conventionally grown or organic/natural foods. CDC recommends that growers practice safe and hygienic methods for producing food products, and that consumers, likewise, practice food safety within their homes (e.g., thoroughly washing fruits and vegetables).”
A University of Minnesota study concerning fecal E. coli in fresh picked produce by Mukherjee et al, published in the Journal of Food Protection (Vo. 67, No. 5, 2004), found that the percentage of E. coli prevalence in certified organic produce was similar to that in conventional samples. However, it did find a marked difference in the prevalence of E. coli between the samples from certified and non-certified organic farms. “Ours is the first study that suggests a potential association between organic certification and reduced E. coli prevalence,” the authors wrote. They noted that the results of the study “do not support allegations that organic produce poses a substantially greater risk of pathogen contamination than does conventional produce.”
What does the organic industry do to ensure safe and wholesome produce?
Certified organic growers and processors not only are inspected by third-party independent certifiers in order to qualify for organic certification, but they also follow strict guidelines for safe and hygienic food production. As with all food producers, they must be in compliance with local, state and federal health standards, and food safety laws. Pasteurization, selected use of chlorine, and other food safety practices also are allowed and followed in organic production.
What is the connection between E. coli and manure use in farming?
Conventional and organic agriculture both use manure as a part of regular farm soil fertilization programs. Certified organic farmers, however, must maintain a farm plan detailing the methods used to build soil fertility, including the application of manure, as mandated by the Organic Foods Production Act (OFPA) of 1990 and the National Organic Program (NOP) rule of December 2000. According to the latter, raw animal manure must be composted if it is to be applied to land used for a crop intended for human consumption, unless it is applied to the land at least 120 days prior to harvest if the edible part crops come in contact with soil, and at least 90 days prior to harvest of edible parts that do not come into contact with soil. OFPA further recommends a longer period if soil or other conditions warrant. No other agricultural regulation in the United States imposes such strict control on the use of manure.
Certifiers and scientists recommend the use of well-composted manure to reduce the incidence of E. coli.
What precautions should consumers take?
It is always important to be careful when handling any food. The U.S. Food and Drug Administration (FDA) instructs consumers to always wash fresh fruits and vegetables thoroughly before eating. Always clean any surface that has come in contact with raw meat before any other item is placed on that surface. Always thoroughly wash hands after handling raw meat, and before handling any other utensil or food item. Always cook meat until the juices run absolutely clear. Prepare meat and poultry separately from fruits and vegetables, and use separate clean utensils for cutting and mixing.
In addition, the Produce Marketing Association recommends the following:
- At the store: trust your senses. Look for fresh-looking fruits and vegetables that are not bruised, shriveled, moldy, or slimy. Don’t buy anything that smells bad. Don’t buy packaged vegetables that look slimy. Buy only what you need. Keep meats separate from produce.
- At home: Handle fresh fruits and vegetables carefully. Put produce away promptly, and keep it in the crisper. Remember to keep all cut fruits and vegetables covered in the refrigerator, and throw away produce you have kept too long. Wash all fruits and vegetables in clean drinking water before eating. Do not use detergent or bleach when washing fruits and vegetables. Store prepared fruit salads and other cut produce in the refrigerator until just before serving. Discard cut produce if it has been out of the refrigerator for four hours or more.
Helpful government sites: