If you’ve ever travelled abroad, you may have visited countries where tourists are given the advice “Don’t Drink the Water”. I have a very distinct memory of traveling in Guatemala and getting violently ill despite being very careful to not drink anything except purified water. Then a friend asked: Did you eat any salad? And in fact I had.
Americans take it for granted that the water they use to flush the toilet will not end up coming out their kitchen and bathroom faucets, but the same is not true everywhere. You may think of our landmark Clean Water Act mostly prohibits dumping of toxic chemicals into lakes and rivers, but it also requires that sewage effluent be treated before it is released into waterways.
Many of the species of microbe that can contaminate water or food come from feces — poop. Salmonella generally comes from rodent or bird poop, including chicken poop. E. Coli comes from rodents as well as other mammals including livestock, wild animals and humans. But one microbe, the parasitic Cyclospora, comes only from human feces.
Cyclospora has been in the news alot lately, thanks to a widespread outbreak of food-borne illnesses in the U.S. that has been linked to iceberg lettuce grown by Taylor Farms — in Mexico. The media coverage of this outbreak has been, IMHO, terrible — as coverage of food safety issues usually is in the U.S. media. This is a big outbreak — thousands of people affected in several states — which provides a clue to the scale of the problem. Cyclospora can be transmitted through poor hygiene, by an individual or group of individuals who aren’t washing their hands after using the bathroom. But that is not going to translate into a multi-state outbreak where likely hundreds or thousands of heads of lettuce were contaminated.
It should be clear at this point that this outbreak resulted from the contamination of an entire lettuce field. There are two ways this can happen. The first would be large-scale flooding of a field by a river or steam. The river might be continuously contaminated, as many rivers in developing countries are. However, under current food safety regulations, any field where fresh vegetables like lettuce are growing cannot be harvested after such a flood. Assuming that a very large company like Taylor Farms was following even minimum food safety practices, that would eliminate the likelihood that the contamination resulted from a flood.
The more likely possibility is that the irrigation water used to irrigate the lettuce was contaminated. Current food safety regulations on irrigation water have changed several times recently as the FDA has struggled to adopt a workable standard that prevents contamination yet doesn’t disqualify most or all agricultural water sources. However, I would say that the current rules are based on the relatively clean water that most farmers in the U.S. use to grow their crops. I think it’s safe to say the FDA rules do not assume that irrigation water is likely to be heavily contaminated with human sewage as water in places like Mexico often is.
This is based on the assumption that produce growers outside the U.S. pay any attention at all to food safety. Technically, all food grown outside the U.S. must meet the same standards for food safety as domestic foods. But the reality is that even in the U.S., enforcement of these regulations is a huge challenge. The idea that the rules are being followed overseas, even if it’s American companies growing the produce, defies logic. And cven if they are trying to grow food that is safe to eat, how can they if the water is routinely contaminated?
In most of the media coverage about food-borne illness, they mention that the incidence of people getting sick from fresh produce is increasing every year — or at least the number of incidents being reported increases. What is rarely reported is that the percentage of fresh produce consumed in the U.S. that is imported is also growing every year. I don’t believe this to be a coincidence or just a correlation. More imported produce = more foodborne illness. The water used for irrigation where those crops were grown likely has a lot to do with it.
Does it make a difference if the produce grown outside the U.S. is organic or conventional? I don’t think so. I have a deep suspicion of imported produce that claims to be certified organic. Corruption is endemic in countries like Mexico, and the profit motive for fraud is huge. But even if there are committed organic growers in other countries, it’s no guarantee they have clean water to use for irrigation.
A question no one in the media is asking is why Taylor Fams — a company based in the Salinas Valley of California, aka, “America’s Salad Bowl “– would be sourcing lettuce from Mexico during the prime lettuce season here. The answer is simple: Growing lettuce and many other crops outside the U.S. costs significantly less than it does to grow them in the U.S., and especially in California. But clearly those cost savings to the company come with a potentially larger human cost. If the company made that calculation while knowing that the local water supply where they were growing the lettuce in Mexico might be contaminated, they essentially made a bet that put thousands of American’s health at risk.
I cannot promise you that fruits and vegetables from Terra Firma will never make someone sick — no one who grows fresh produce can. Outdoor fields are exposed to birds, rodents, and mammalian wildlife that can potentially contaminate the crops without the farmer becoming aware of it. Much of our produce is hand-harvested, and while our employees are trained to always wash their hands and stay home if they are sick, it’s still possible that bacteria may be transmitted.
However, I can make one promise to you — as can most American farmers who grow fresh produce: the water we use for irrigation has zero potential for contamination from human sewage.Terra Firma’s irrigation water comes from one of two sources: deep groundwater wells, or Lake Berryessa (which is the source of drinking water for the cities of Vacaville and Fairfield). While not all of our water sources meet drinking water standards since we do not treat it, it does meet recreational water standards for swimming. There are no sewage treatments upstream of our farm. That makes it lower risk than other local surface irrigation water sources that are used for farming in this area, including Clear Lake — the source of water for most farmers north of us in Yolo County — and the Sacramento River, which is the source of water for thousands of farms in the Central Valley. But even those water sources have little risk of Cyclospora contamination.
In my (clearly biased) opinion, if you want to avoid getting sick from fresh fruits and vegetables, you should start by checking the label to see where they are grown. Some items are less likely to be contaminated by irrigation water, such as avocadoes and tree fruit. Tomatoes are generally grown on trellises with drip irrigation so the fruit has no contact with water. But I would never eat lettuce grown in Mexico — even when visiting.