Toxicologist Halimatou Traoré knew that chemists in West Africa needed a workshop to train them in the newly acclaimed “QuEChERS” (pronounced “catchers”) pesticide residue analysis method. Not only would learning this technique give them a “quick, easy, cheap, effective, rugged, safe” method (the acronym comes from the adjectives) for extracting and analyzing pesticide residues on fruits and vegetables, it would also enhance their credibility with international standards organizations. They could be sure that crops in West Africa do not exceed the maximum residue level standards set by the European Union for importing mangoes, tomatoes and green

beans—the most important cash crops of West Africa. Finally, the workshop would be a valuable networking opportunity.

The dream of putting on such a workshop was one thing, but the wherewithal was another. Enter Virginia Tech researchers Don Mullins, Pat Hipkins, and Jean Cobb, who have been working on a USAID-supported project in integrated pest management in West Africa since 1999. Halimatou, head of quality control at a government toxicology lab in Bamako, had worked with the Virginia Tech group over the years, and it was through her friendship with the researchers that the workshop came about.

Cobb, senior project associate of the Pesticide Residue Laboratory at Virginia Tech, said, “We had the dream of doing a QuEChERS workshop in September of 2005, but had no idea that Mr. QuEChERS himself would one day be here.” In fact, “Mr. QuEChERS,” Steven Lehotay, led the hands-on four-day workshop, which he also designed.

QuEChERS was developed by Lehotay and other researchers in his lab at the USDA-ARS Eastern Regional Research Center at Wyndmoor, Pennsylvania. What makes the novel sample preparation technique so appealing is its ease, low cost, and high quality results. All one needs are non-breakable tubes, small quantities of chemicals, and a centrifuge to get a sample ready for injection on instrumentation. In the past, one needed many types of specialized pieces of lab equipment, large quantities of chemicals, and much more time to process samples. The traditional multi-residue methods easily took two to four times as long as the QuEChERS method.

“QuEChERS is worldwide now,” Cobb said. “It has become the gold standard for fruits and vegetables.”

At the Bamako workshop on August 24, 2007, chemists from government, private, and university laboratories representing five West African countries learned the innovative method. The chemists understand that assuring low-residue/no-residue agricultural products is critical to maintaining vital trade with Europe and elsewhere. “If you don’t guarantee your produce as being pesticide-free, you run the risk of becoming blacklisted, essentially cut out of international trade,” explained Cobb. When this happens, it seriously affects a country’s income from agriculture. (continued...)

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