When the pesticide methomyl is sprayed on crops, farm workers aren&rsquo;t supposed to step back into the fields for up to a week.</p><p>It&rsquo;s dangerous, potentially deadly stuff and, according to federal prosecutors, it is the poison a Shawnee couple chose to exact revenge against one of the owners of the Mi Ranchito restaurant in Lenexa. </p><p>On Thursday, federal prosecutors accused former restaurant employees Arnoldo Bazan and his wife, Yini De La Torre &mdash; niece of the restaurant co-founder &mdash; of mixing the pesticide into salsa Aug. 30 and sending at least a dozen people to the hospital. </p><p>Bazan, 30, and De La Torre, 19, each face one count of conspiring to recklessly endanger other people by conspiring to tamper with a consumer product. They also are charged with two counts of tampering with a consumer product.</p><p>Prosecutors allege the couple poisoned the salsa to make customers sick so the restaurant would be blamed and hurt financially.</p><p>Methomyl is a hard-to-get pesticide used for commercial fruit, vegetable and cotton crops. It can be purchased and used only by certified professionals</p><p>&ldquo;It&rsquo;s not like you, me or John Doe can go and get it,&rdquo; said Tama Sawyer, director of the University of Kansas Hospital&rsquo;s Poison Control Center.</p><p>Sawyer said 7.5 small drops of undiluted methomyl can be lethal. She said she had not seen a case of exposure to the pesticide in the 20 years she had worked at the center.</p><p>In a statement released Thursday, federal authorities laid out the case this way:</p><p>Bazan worked at Mi Ranchito until June 27. He blamed the restaurant&rsquo;s owner for the loss of his job and vehicle.</p><p>In July, an anonymous note was sent to Mi Ranchito&rsquo;s Web site threatening harm if Bazan didn&rsquo;t get his vehicle back.</p><p>On Aug. 11, De La Torre added methomyl to salsa, authorities allege, and a day later customers started getting sick.</p><p>A little more than two weeks later, Bazan sent word to the owner through an intermediary that &ldquo;the worst&rdquo; was yet to come.</p><p>On Aug. 30, authorities allege, his wife mixed more methomyl into salsa. Three dozen customers fell ill with nausea, sweating, weakness and cramps, and at least a dozen were rushed to the hospital.</p><p>De La Torre told reporters that day that the salsa was the source of the problem. That was her last day at the restaurant.</p><p>A little more than a week later, Bazan told her not to talk to investigators or she would be physically harmed, authorities said.</p><p>Restaurant co-founder Rulber De La Torre, uncle of Yini De La Torre, said the bad publicity from the incidents had hurt him much worse than the economy.</p><p>&ldquo;I gotta tell you, this is the closest I&rsquo;ve ever been to going out of business,&rdquo; he said.</p><p>The charges announced Thursday were a &ldquo;huge relief,&rdquo; he said. &ldquo;Justice is the best thing that could have happened to me. We&rsquo;re coming back fast.&rdquo;</p><p>A spokesman for U.S. Attorney Lanny Welch said Bazan was in custody on another charge he could not specify. He said De La Torre would surrender.