"Having now researched trenbolone, we have discovered that it is a USDA approved steroid, legally used in the United States in the production of beef,” Lawson said in a statement, according to his agent. “Lab results have shown that there were extremely trace amounts of the metabolite in my sample. We are confident that we will prove that the metabolite entered my system through contamination. The Athletics Integrity Unit has been very helpful in providing us with the information needed to make our case. I am a 100% clean athlete and a big supporter of a clean sport. I am completely confident that a fair decision will be made in this case and I will be cleared of any wrong doing.”
https://olympics.nbcsports.com/2018/08/31/jarrion-lawson-doping-ban-long-jump/