(AP/J. Scott Applewhite)

The Food and Drug Administration on Friday finalized long-awaited rules that establish the first federal standards for how fruits and vegetables are grown, harvested and packed in the United States.

"It’s been a long and arduous task, to say the least," said Michael Taylor, FDA's top food safety official, who has crisscrossed the country in recent years to address the concerns of large and small producers alike, from apple farmers in Maine to onion growers in Oregon. "Finalizing the rules is just one part of building a modernized food safety system."

Growers subject to the new regulations will face an array of responsibilities -- ensuring the safety of water used in irrigation, for example, or making sure workers practice good hygiene while harvesting and packing, or keeping deer and other wildlife away from planted fields so their waste doesn't contaminate crops.

"It’s going to be a sea change for the industry," said Jim Gorny, vice president for food safety and technology for the Produce Marketing Association, a national trade group that largely supported the FDA's efforts.

[Can the FDA actually prevent foodborne outbreaks instead of just reacting to them? We're about to find out.]

Like other experts, Gorny said many fruit and vegetable growers around the country already adhere to the new standards. But the rules essentially amount to a set of best practices that will apply to most farms and packing houses.

"A rising tide lifts all boats, and everybody going to have a minimum standard they’ll have to abide by," Gorny said. "This is certainly a big step forward."

The produce rule is a key piece of a far-reaching law, signed by President Obama in early 2011, that marked the first major overhaul of the nation's food-safety system in generations. That legislation was aimed at putting in place safeguards to prevent foodborne illnesses, rather than to only react to outbreaks. Tainted foods sicken an estimated 48 million Americans each year, sending 128,000 to the hospital and killing several thousand, according to the Centers for Disease Control and Prevention.

In addition to the produce rule, the food-safety law mandated a series of other reforms. Among them: Manufacturers must create plans to identify and prevent contamination risks in processing plants, and food importers must verify that their foreign suppliers are producing food at a level that meets U.S. standards. (The FDA also finalized the details of this latter requirement on Friday).

Taylor said the produce rule in particular is meant to prevent the type of high-profile outbreaks that have become commonplace in the United States. Those episodes have involved spinach tainted with E.coli, cantaloupes contaminated with Listeria and a recent multistate outbreak of salmonella in imported cucumbers that has killed four Americans and sickened hundreds of others.

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The new regulations do contain exemptions for certain people and certain foods. For instance, the rules exempt farms with average annual sales of $25,000 or less, as well as certain farms that bring in less than $500,000 a year and sell primarily to consumers within a 275-mile radius. Smaller farms also will have much longer to comply with the new rules, which will be phased in over the next several years.

The FDA exempted a lengthy list of fruits and vegetables that it said are usually cooked or processed prior to being consumed, and therefore are less likely to harbor pathogens. That means pecans, peppermint, potatoes and pumpkins are exempt, while papayas, parsnips, passion fruit, peaches, pears, peas and peppers are covered.

Disagreements remain, especially around how -- and how often -- farmers must test their water supplies for contamination.

"It's a very touchy issue, water," said Gorny, noting that irrigation water can come from wells, rivers, reservoirs and any number of other sources, making it difficult and costly to take the ongoing number of samples being required by regulators. "FDA has taken an approach we're concerned about; it's pretty prescriptive ... We're concerned about the total number of samples, the costs and the standards they've chosen."

Still, Gorny and others said the agency has solicited widespread input from the industry, and Taylor on Friday said the FDA would continue to evaluate how best to ensure the safety of water supplies on farms.

How well and how quickly the new rules take hold will depend, at least in part, on how much money Congress gives the FDA to implement them. The Obama administration requested nearly $110 million for the coming year to fund the implementation of the new food-safety legislation. The Senate and House draft budgets currently call for no more than $45 million.

Sandra Eskin, director of food safety at The Pew Charitable Trusts, said it's more important than ever for lawmakers on Capitol Hill to actually fund the legislation they passed five years ago.

"It's crunch time," Eskin said, noting that FDA needs to hire more food-safety experts and train state regulators who will help implement the new rules. "This is prevention-based regulation, and it costs money ... But these rules are ultimately going to benefit society."

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