Farmers will soon have to start testing their water to comply with the Food Safety Modernization Act.
Produce growers must be compliant with the rule’s water testing requirements two years after their compliance date for the other FSMA requirements, said Don Stoeckel, a Cornell Cooperative Extension food safety associate.
The smallest regulated farms, which sell $25,000 to $250,000 in produce a year, have until January 2022 to comply.
Stoeckel spoke about the water testing requirements in an eXtension webinar on Tuesday.
For untreated surface water, farmers must do an initial survey of at least 20 samples collected as close to harvest as possible over two to four years, Stoeckel said.
These tests are used to calculate the geometric mean — an average of the samples — and the statistical threshold, which accounts for big jumps in bacteria levels.
Such spikes would come from feces, either human or animal, entering the water upstream from the farm, Stoeckel said.
The U.S. Food and Drug Administration, which is implementing FSMA, says the criteria were designed to allow for occasional high readings of E. coli, reducing the chance that a farmer will have to stop using a water source because of small changes in quality.
If the water does not meet the requirements, corrections are required as soon as possible, but no later than the following year, according to FDA.
Untreated surface water may not contact produce. Farmers need to find some other water source for food contact surfaces, hand washing water, sprout irrigation water and ice.
If E. coli is detected in water that will touch produce, farmers must stop using the water immediately and correct the problem.
For untreated groundwater, FDA requires four tests in the first year. If those tests are OK, testing can be done once every year after that.
If water does not meet the accepted levels, Stoeckel prefers that farmers find out what the problem is and fix it.
Alternatively, the rule allows farmers to treat the water to kill the bacteria, though no products are currently labeled to treat irrigation water. That means any treatment is off-label and illegal right now, Stoeckel said.
A third option is to wait for the bacteria to die off between irrigation and harvest.
Farmers may account for a 0.5 logarithm per day reduction, up to four days, Stoeckel said.
Some guidance on water testing procedures has yet to be released, so farmers may not be able to start building their water quality profile this year, Stoeckel said.
The produce safety rule is a minimum requirement. So following its rules may not always be enough to deliver safe produce, Stoeckel said.