Pepper plants sop up personal care product antibiotics

The U.S. Food and Drug Administration recently banned TCC from soaps because of questions about its safety and efficacy. Yet, TCC remains in many other products. It's also found in high concentrations in treated wastewater that is sometimes used to irrigate crops. The impact of TCC on human health remains unclear, but it may act as an endocrine disruptor. One obstacle to better understanding the risks of environmental TCC exposure is uncertainty about how much of it ends up in plants, and how plants metabolize the substance. So, Dawn Reinhold and colleagues undertook a study with jalapeno peppers to address this knowledge gap.

To track the antibiotic's journey from water to pepper, the researchers labeled TCC with radioactive carbon (C14). They grew the pepper plants hydroponically and, after 12 weeks, sampled the C14 content in the roots, stems, leaves and fruit. While the pepper fruit itself had relatively low levels of TCC, it contained a hefty portion of C14 in molecules that started out as TCC but then were converted to other molecules by the plant. According to the researchers, this finding indicated that the plant was metabolizing the antibiotic, and the health impact of these metabolites would need to be taken into account to fully assess the safety of TCC consumption.