Did the tomato do it?

The tomato is the prime suspect as the source of the salmonella outbreak that has sickened hundreds across the US in recent weeks. However, US government regulators still have little idea where the outbreak started, let alone that the tomato is definitely the guilty fruit.

The outbreak is the largest produce-linked salmonella outbreak in the US with 810 people in 36 states sickened to date. It is estimated to have cost the food industry at least $100 million as consumers eschew tomatoes and some crops rot on the vine.

Scientists have not established how tomatoes can be contaminated. Some experiments show bacteria can enter tomatoes submerged in cold water. Others suggest salmonella-contaminated water can enter through the stem or flower of a tomato plant. For now, the FDA recommends consumers avoid raw red round, red plum and red Roma tomatoes unless grown in a state not yet implicated in the outbreak.

As tomatoes are the second-highest sellers (behind packaged salad) in grocery stores’ produce sections, the fallout is considerable.

Lisa Lochridge, spokeswoman for the Florida Fruit and Vegetable Association, said the scare could cost hundreds of millions of dollars. “The ripple effect is huge: it's not just the growers but everyone on the supply chain — the packers, the shippers, on down to food service and the retail level.”

The extended US food chain and the system for distributing fresh produce have exacerbated the difficulties in isolating the source of the outbreak. At the same time, the economic fallout continues to impact all sorts of companies which are not necessarily implicated at all.

Investigators from the FDA have collected 1700 samples from packing, washing and storage facilities in Florida and Mexico but none have so far proved positive for the virulent Saintpaul salmonella strain.

The FDA has said that it may never find the culprit. “It's important to control expectations, and it's possible that this investigation will not ultimately provide a smoking gun,” said David Acheson, the FDA's associate commissioner for foods. “That's not that unusual with tomato outbreaks.”

The uncertainly has left consumers jittery and many in the tomato industry angry. Tom Nassif , a spokesman from Western Growers, a trade group representing most of the fresh-produce industry in California and Arizona, has stated: “The collateral damage inflicted on thousands of innocent producers in this country by FDA blanket ‘advisories’, such as with spinach and tomatoes, cannot go unchallenged.”

The outbreak is also adding to tensions between tomato growers in Florida and Mexico. Mexican imports to the US have soared since the mid-1990s, and Florida growers have lobbied for import curbs and tougher regulation of Mexican tomatoes. Last year, Mexico exported about $960 million worth of tomatoes to the US, accounting for almost 80% of the import market.

Contaminated produce scares are not restricted to the US nor is fallout following outbreaks affecting many totally innocent companies. The solution is to have rigorous food safety practices and rigorous traceability standards.