Food safety issues pose a more serious threat to the produce industry than damage from insects, plant diseases and other pest problems.

And some of those safety concerns may be reduced by paying closer attention to water, says Texas AgriLife Extension plant pathologist Juan Anciso.

Anciso, who works from the Texas A&M Research and Extension Center in Weslaco, discussed water quality issues during the recent Texas Food Safety Conference in Austin. He said producers, handlers and shippers all need to be aware of water quality concerns. Contamination may occur pre-harvest or post harvest, he said.

Pre-harvest issues include irrigation and irrigation sources. Post harvest concerns include wash water and produce sanitation. “Good agricultural practices must include water testing protocols,” Anciso said.

Irrigation sources affect contamination risk. Anciso said surface water “poses the greatest potential for contamination. Effluent runs into rivers (and other surface water sources) and contaminates the water. Pathogen numbers may be high in rivers.”

Ground water is less likely to be contaminated. “If ground water tests positive for contaminants, something is wrong,” Anciso said. “A cracked well head or other problem allows contamination.”

Municipal water sources are the least likely to be contaminated.

Irrigation methods also affect potential for contaminants to affect produce. “Subsurface drip irrigation is the least likely to contaminate,” he said. Furrow irrigation is a bit more likely (to contaminate) and overhead spray systems pose the greatest potential for contamination. “The less potential for water to contact the plant, the less likely contamination will occur.”

He said producers should “know the watershed. Identify any possible point or non-point pollution sources. Follow best management practices to reduce pollution. The more you understand where water comes from and how it is delivered, the better you are able to assure less contamination.”