Public interest in the environment is increasing, and the news is full of stories about food safety. Those developments have led many to push for a return to small organic farms.

Such farms do have advantages, but there is no guarantee that organic farms are better for the environment or food safety.

Organic farms ban the use of pesticides and genetically modified organisms, minimizing inadvertent effects on other organisms. However, whether such avoidance makes organic production "better" for the environment is largely a matter of personal priorities. For the most part, these chemicals, used properly, don't pose any net threat to the environment. Many objections to their use are philosophical rather than scientific.

Further, the required soil conservation practices are not unique to organic production. Many traditional growers use the same practices, even though not required, because of the associated soil fertility and erosion mitigation benefits.

Some types of organic food, such as poultry, require more energy to produce than their conventional counterparts. Production of organic milk requires more land input and generates more CO{-2} emissions.

Some may argue that organic production means more local food, thus cutting down the environmental impacts of the associated "food miles."

But a recent study from the United Kingdom's Department for Environment, Food and Rural Affairs suggests that for some foods, global production might have a smaller environmental footprint than local production. While global products are transported long distances, they are also produced and transported in very large quantities, creating positive economies of scale.

Purely local food production is limited to only those crops well-suited to being grown in the local environment. This means a considerably diminished variety of foods for most consumers, and many organic foods are still transported long distances for this very reason.

Nor is it true that organic foods are necessarily a safer and healthier option than conventionally grown food. In a recent analysis of government data on fruit, vegetables and meats, Consumer Reports found that foods such as asparagus and bananas, even when treated with pesticides, do not tend to contain detectable levels of pesticides anyway. While the concept of any pesticides in or on our food sounds scary, the majority of conventional foods have no detectable pesticide residues.

There is the possibility of disease outbreaks from any food; the spinach responsible for last year's E. coli outbreak was grown on a small organic farm.

A comprehensive 2002 review of scientific research found that with the possible exception of nitrate content, there is no strong evidence that organic and conventional foods differ in concentrations of various nutrients.

We should continue to investigate sustainable farming practices. But the public should understand that conversion to small organic farms will not necessarily have notable environmental and food-safety benefits.