Finding Dioxins In The Japanese Tsunami’s Aftermath

Because of the Tohoku earthquake and tsunami that devastated Japan’s Pacific coast in 2011, a huge cleanup operation is underway. To help protect workers processing industrial waste scattered by the disaster from refineries and factories, researchers have developed a way to detect toxic polychlorinated compounds including dioxins more quickly than the standard government technique can (Anal. Chem., DOI: 10.1021/ac3028917).

“Quick detection of toxic substances like dioxins is important for the people clearing the waste sites,” says Totaro Imasaka from the Center for Future Chemistry at Kyushu University. That’s because it allows workers to take appropriate safety precautions when clearing the sites. The government-backed method of gas chromatography and high-resolution mass spectrometry uses electron ionization. The technique ionizes a huge range of organic compounds in each sample. To make the analysis easier, the researchers must first separate the components of the sample using column chromatography, a process that requires time and care, Imasaka says. The resulting mass spectra also take a long time to analyze. As a result, the process can take up to two weeks.

Imasaka, along with a graduate student, Yu-Ching Chang, ionized the sample with a high-powered laser, which is more selective and makes fewer fragments. As a result, they had no need to run column chromatography before analysis. They used a femtosecond laser with gas chromatography and time-of-flight mass spectrometry to test seven soil samples from around the tsunami-affected area, quickly picking out four that contained dioxins. The team could identify all significant chemical species at one time in a process that took only three to four hours, Imasaka says.