GRAND RAPIDS, Mich. (WOOD) — Marijuana has become a big business industry in Michigan, but hemp is the plant of 1,000 uses. Researchers at Northern Michigan University believe that versatile plant can even be used to help remediate soil contaminated with PFAS.
NMU chemistry professor Lesley Putman says early experiments show that hemp can absorb at least one type of PFAS without any noticeable side effects.
“We grew industrial hemp hydroponically and added PFBA (perflurorobutanoic acid) to the water in which the plants were growing. The hemp took it up into the leaves, stems and flowers, and it didn’t affect the growth of the plant,” Putman said in a university blog post.
The experiments were repeated in a greenhouse setting and showed similar findings. Experiments with PFOS (perfluorooctane sulfonic acid) and PFOA (perfluorooctanoic acid), the two most popular forms of PFAS, weren’t as successful, but still showed a lot of promise.
“Because those are larger molecules that don’t move as easily and aren’t as water-soluble as small ones, they didn’t go up into the leaves as readily and were sequestered in the roots. But nevertheless, if hemp can hold them up, that’s a good starting point,” Putman said.
PFAS — or per- and polyfluoroalkyl substances — are a large group of compounds first developed in the 1940s and incorporated into all sorts of products for waterproofing and heat resistance. Decades later, research showed that PFAS compounds take a long time to break down organically and can build up in the human body, causing serious health problems including cancer.
Over the last several years, many researchers and environmental groups have worked on ways to remediate soil, water and other items contaminated with PFAS. Putman believes hemp could be cheaper and just as effective as the current remediation methods.
The primary issue, however, is that hemp treatments do not destroy the PFAS. Rather, the chemical is simply transferred to the hemp plants. For the study, Putman is working with a local company licensed to handle toxic waste, but the goal is to expand the research further and see if there is another step the researchers could take to break the tightly held bonds and destroy the chemical compound. One former researcher recommended experimenting with fungi. Another possibility is two naturally occurring bacteria that speed up the PFAS breakdown process.
Unlike marijuana, hemp has an extremely low level of tetrahydrocannbiol or THC, the psychoactive component of the plant that produces a “high.” Hemp is already used in several other materials, everything from health products and food to fabric and rope.