WHEN I WAS IN THE THIRD GRADE, I read Laura Ingalls Wilder’s book Little House on the Prairie.  The story of a little girl on the frontier was totally engaging, but what I remember most about the series is the food.  The Ingalls family was never hungry, but their diet was limited.  Laura’s excitement over an occasional treat made that clear.  In one chapter, she goes to a birthday party and receives a whole orange – just for her.  In another, she hopes there will be some pork left over by the time she gets to eat at a party.  Oranges?  Pork?   Those definitely did not seem like treats to me.  I felt sorry for her when she finally got a piece of actual candy – a single candy heart from the general store – and she couldn’t even allow herself to eat it because it was too pretty.

    In my modern American life, I can find any almost fruit or vegetable, cut of meat, or variety of cheese at any grocery store any day of the year.  I can open a cookbook for any kind of cuisine and, with very little effort, buy the ingredients for any dish I want to make.  My food supply is marked by reliability and variety.  How the developed world transitioned from a primarily small farm based agricultural system to an industrialized one is a big subject, and one I don’t know much about (nor is it a transition I regret – I’m glad I’m not a farmer like my ancestors were).  But it is clear that the way our food is produced today is dramatically different from how it was a century ago.  It’s also clear that over the past 20 years there has been a growing rejection of conventional industrialized farming in favor of organic methods.  Is this trend justified based on real dangers associated with conventional farming, or is it the result of overblown fears and misinformation?

    Modern agriculture depends on technological implements such as synthetic fertilizer and pesticides, specially bred crops (especially cereals), heavy machinery, and irrigation.  Traditional agriculture depends on crop rotation and natural fertilizers to supply plants with nitrogen, but during World War I, the Haber-Bosch process made synthetic nitrogen fertilizer widely available, freeing farmers to develop monoculture.  In the 1940s, chemical pesticides emerged and became widespread in farming.  In 1945, Norman Borlaug of the Rockefeller Institute took his results from a 20-year wheat breeding program, along with synthetic fertilizer and other implements, to Mexico and turned the country from a wheat importer to a wheat exporter.  This success was repeated in India in the 1960s and China in the 1980s.  “The Green Revolution,” as Borlaug’s work is now known, is credited with allowing food production to keep pace with worldwide population growth, and he won the Noble Peace Prize for it in 1970.

    Almost as soon as modern implements like chemical fertilizers and pesticides came about, the organic farming movement began.  The term organic farming was coined by British agriculturalist and scholar Lord Northbourne, in his 1940 book Look to the Land.  In it, he advocated thinking of a farm as an organic whole, and this remains an important goal of organic farming today.  In order to be certified organic, crops must be produced on farms that use no synthetic fertilizer or pesticides, and livestock must be raised without growth hormones or routine antibiotics.  Crops cannot be genetically modified or irradiated, and food additives must be on the National Organic Program’s short list of approved substances.  Organic farmers use crop rotation, manure, and compost to replace synthetic fertilizers, and natural pesticides, mulching, and hand weeding to cope with pests.  Yields are lower, and human inputs higher, which, in combination with the cost of complying with tight EPA regulations, makes organic food more expensive than conventionally grown food.  More and more people are willing to pay the price.  The organic food market has grown by about 20% per year since the early 1990s.  People may choose organic for a variety of reasons, including the fact that it is more energy efficient and less polluting than conventional farming, but health concerns regarding chemical residues on food are often primary.  So, it is worth asking what risks modern conventional farming present, and whether organic food is healthier and thus worth the price.          

                                                                                                                                                                                                                             

    IN 1993 THE NATIONAL ACADEMY OF SCIENCES released the report “Pesticides in the Diets of Infants and Children,” which acknowledges that pesticides have improved human health by increasing crop yields, but also notes that they pose significant health risks due to their toxicity.  Pesticides are inherently toxic – it’s the reason they’re effective at killing plant and animal pests.  Some known risks of pesticides, as shown by studies in lab animals, include birth defects, nerve damage, cancer, and possibly fertility problems.  Infants and children are particularly sensitive because they eat more in proportion to their body weight than adults do, and they consume far fewer types of foods than do adults.  The EPA regulates pesticide use; the amount of pesticides present on food, called the residue, must not exceed the tolerance level, which is the amount of the pesticide on an agricultural product that is considered safe by the EPA.  The 1993 National Academy report describes tolerances this way:

      “Tolerance concentrations are based primarily on the results of field  

      trials conducted by pesticide manufacturers and are designed to

      reflect the highest residue concentrations likely under normal

      conditions of agricultural use. Their principal purpose is to ensure

      compliance with good agricultural practice. Tolerances are not based

      primarily on health considerations.”

    Not based primarily on health considerations?  That was very worrisome, especially for children because, as the report continues, “exposure to pesticides early in life can lead to a greater risk of chronic effects that are expressed only after long latency periods have elapsed. Such effects include cancer, neurodevelopmental impairment, and immune dysfunction.”

    The report recommended that safe exposure levels be based on what is safe for infants and children, and since tolerances constitute the only tool that the EPA has under law for controlling pesticide residues in food, it also recommended that the EPA re-evaluate it’s process for determining tolerances so that it is based more on health considerations and less on agricultural practices.

    THE NATIONAL ACADEMY REPORT led to the Food Quality Protection Act (FPQA) of 1996.  This act directed the EPA to develop health-based standards for pesticide tolerances and required that some 9,600 tolerances covering pesticide residues in food be updated within 10 years.  The review was completed in 2006.  Some pesticides were taken off the market, other remained because the EPA concluded that they met the safety standard required by the FPQA.

    As a consumer, I feel reassured that the EPA has recently reviewed the pesticides found on my food, but at the same time disconcerted that it took over 50 years from the time pesticide use became ubiquitous for the government to make health considerations a standard by which safety is judged.  Rachel Carson’s Silent Spring, the book that first drew attention to the problems of synthetic pesticides, was published in 1962, so why did it take 34 years to get the FPQA?  The chemical industry mounted a huge campaign to discredit Carson and minimize government oversight, and I can only assume that was a major factor.  I do not believe that government agencies are impervious to lobbying from industry (nor from environmental activist groups for that matter).  On the other hand, the EPA has nothing to gain by allowing hazardous levels of toxic chemicals in the food supply.

    In 2006, four scientists at The Organic Center, a nonprofit organization dedicated to promoting organic farming techniques, wrote a report evaluating pesticide residues in food after the FPQA enactment.  They found that pesticide “exposure” had decreased by a third, but pesticide residues in imported food were up (although still in compliance with EPA regulations).  They also criticized the EPA for not reducing dietary exposure to some of the riskiest pesticides, particularly organophosphates.  (Organophosphates cause neurological impairments in lab animals and have been linked with motor and attention deficit problems in humans.  Since 1996, 17 organophosphate pesticides have been taken off the market.  Thirty one remain, with the EPA stating they meet the safety risk standard for the FQPA.)

    The Organic Center believes EPA tolerance levels for pesticides are too high, but it seems to me that they believe the only acceptable amount of pesticide is zero.  Dose does matter, as Paracelsus, the father of toxicology said: “the dose makes the poison.”  As an example, in 2002 a group of Swedish researchers found the chemical acrylamide in starchy foods that are cooked at high temperatures, so it is present in baked potatoes, French fries, chips, breads, and other baked goods (but not in boiled or raw foods).  Acrylamide is a neurotoxin and possible carcinogen. But the Food and Agriculture Organization of the World Health Organization gives acrylamide a “no adverse affect level” of 0.5 mg/kg body weight per day, and given the acrylamide amounts measured in food, the average woman could eat 92 pounds of French fries every day and still have consumed less than half the no adverse affect level of acrylamide.  In spite of this, the California attorney general’s office sued 4 major food manufacturers for not listing acrylamide as a potential carcinogen in their products (they settled out of court for a combined amount of $ 2 million).  This is ridiculous.  I think that science’s ability to detect vanishingly small quantities of chemical compounds, matched with people’s natural tendency to worry, can mean that panic trumps reason at times.  I found it funny and strange that The British Food Standards Agency found it necessary to write “eating is not a risk free activity” in reference to the acrylamide scare.

    MANY MAINSTREAM DOCTORS and scientists do not believe synthetic pesticides are a significant health risk.  The Mayo Clinic website states “most experts agree that the amount of pesticides on fruits and vegetables poses a very small health risk.”  Extoxnet, a pesticide database maintained by five universities, claims to give “objective, science-based information about pesticides.”  They write that “pesticide levels tend to decline over time because the residues break down and because crops are usually washed and processed before reaching the marketplace.   So … levels in our food generally are well below legal limits by the time the food reaches the grocery shelves.”  For anyone interested, you can get nitty-gritty details on any pesticide in use at Extoxnet.  But no one has time to become an expert on pesticides; in my opinion, this is why we have an EPA.  At some level we must rely on authorities to evaluate the safety of foods we buy and eat – be they scientists at The Organic Center or scientist contributors to Extoxnet.  Ultimately, I think whether or not one trusts that the EPA is adequately protecting consumers from toxins may be more of an emotional than a rational decision.

    Whether or not to buy organic depends on your comfort level regarding risk.  It is fairly straightforward to test acute effects of high doses of pesticides, but much harder to determine the effects of long-term, low-level exposure.  I cannot be certain that low-level pesticide exposure will not eventually give me cancer, but pesticide residues on conventionally grown foods fall below the threshold of risks that I worry about.  For infants and children, however, I do have nagging concerns about sensitivities to chemicals – in spite of the fact that the EPA is required to make tolerance levels safe for children.  The same goes for pregnant women.  However, I don’t think it’s necessary for children to eat a totally organic diet.  If my son eats blueberries a few times a year, I’m not going to worry if they’re not organic.  But I do think it would be a good idea to make a list of the few foods your children consume the most of and buy those organic.  For adults, I would check this list of the foods with the highest pesticide levels, and if you eat a lot of anything on it, then maybe buy those things organic.  A 2008 Organic Center Report said that foods with the very lowest pesticide levels are onions, grains, meats and poultry, bananas, citrus, and pineapple.  Washing and scrubbing fruits and vegetables and throwing away the outer leaves of lettuce and other leafy vegetables will help remove pesticides.  Some people recommend peeling all your fruits and vegetables, but that would mean removing a lot of nutrients, so I wouldn’t do it.  Overall, a varied diet mainly composed of fresh produce and whole grains is the healthiest way to eat, whether the food comes from an organic farm or not.

                                                                                                                                       

Want to read more?

I think The Organic Center is a balanced source of information on organic food. 

Extoxnet has a good list of FAQs that are worth browsing.

The EPA website is hard to navigate and not that useful unless you’ve got a lot of time on your hands.