National Editor Tom Karst
National Editor Tom Karst

One web page that all industry leaders should bookmark is the produce safety rule docket at  

With more than 600 comments received so far on the FDA's proposed produce safety rule, one can begin to identify what issues are flashpoints for the regulations.

Here is a comment from Donna Pahl of Maryland about the water quality requirements, whcih FDA officials have said was perhaps the most difficult to compose. Pahl is an extension GAPs educator at the University of Maryland.

From the comment:

Comment on Water Quality Requirements in Food Safety Modernization Act

Our lab is writing to comment on the proposed microbial regulations for the quality of crop spray water in the Food Safety Modernization Act. The proposed regulations call for agricultural water that contacts the edible portions of covered produce to be “safe and of adequate sanitary quality for its intended use”. The proposed regulations state that any water that contacts the edible portion of crops should test under 235 cfuE.coli/100ml in a single test, or 126 cfuE. coli /100ml as a rolling average.

We work as GAPS educators and researchers at the University of Maryland. One of the universal concerns that growers express is the proposed recommendation for water used in preparing crop sprays. Growers throughout the Mid-Atlantic use surface water sources (ponds, springs, and canals) to mix with pesticides for contact application. Since groundwater and wells are not always available near their fields, this is a common practice. Crop sprays are typically applied to the edible portion of the plant.With pesticide application, only a limited amount of water is sprayed onto the crop – ranging from 30 to 300 gallons per acre. This differs significantly from overhead irrigation, which requires about 27,000 gallons per acre inch of irrigation water.

In our own research, we found that the levels of E. coli present in water used for the application of crop sprays did not have a significant impact on the microbial load on the surface of tomatoes. The two publications listed below are linked field studies completed by our lab. Water sources of significantly different water quality (groundwater and ponds) were used to prepare and apply pesticides to tomatoes. Twenty-four hours after the pesticide application treatments, tomatoes were harvested, rinsed, and massaged to elute surface bacteria. The resulting washwater was tested with conventional microbiological and molecular methods. Even after performing the non-recommended practice of applying water with high levels of fecal indicator organisms, there were no significant differences in the microbial load on the tomatoes. For more detail, please reference the publications listed below.

We ask that the FDA closely consider the science available when determining the water quality standards in the Food Safety Modernization Act for crop spray application water. While we always teach growers the value of water quality, our research showed less effect on the microbial quality on covered produce than we had expected. Enacting the proposed water quality standards on crop spray water without sound scientific evidence may result in unnecessary financial burden on fruit and vegetable growers attempting to comply with FSMA.


The comment illustrates the challenge the FDA has in implementing "science-based" regulations on issues such as water used for the application of crop sprays.  This is just one of 1,000 issues that show how time-consuming and difficult writing and implementing the produce safety rule will be.