New research from Michigan State University has shown for the first
time that activated carbon – a substance widely used in water
purification – can help eliminate the health risks associated with
soils, sediments and surface water polluted by highly toxic dioxins.
Stephen
Boyd, a University Distinguished Professor in the plant, soil and
microbial sciences department, led the study, which is published in the
journal Environmental Toxicology and Chemistry.
The research looked specifically at soil and freshwater ecosystems that
were contaminated mainly through the industrial manufacture of
pesticides and other chemicals.
“The goal is to find and validate a
new direction in the management and remediation of soils and sediments
that are contaminated with industrial pollutants, like dioxin,” Boyd
said. “We were finally able to achieve that goal with activated carbon.”
Activated
carbon is produced when materials with high carbon concentrations, such
as coal, wood, peat or even coconut shell, undergo special treatment
processes that expose them to extremely high temperatures without
burning them. The result is a porous, highly adsorptive substance that
binds easily with organic toxins. When mixed into contaminated soil or
sediment, the activated carbon draws dioxin to it and sequesters it.
Though
the release of dioxins into the environment has been reduced by more
than 90 percent since 1990, the toxins already released continue to
persist in the environment, and can enter the food chain through fish
and other organisms.
“There’s a general malaise of health issues
associated with dioxin contamination,” said Brett Sallach, plant, soil
and microbial sciences postdoctoral research associate, who worked on
the project. “Hormone health complications, fertility issues, skin
rashes, immunity problems, cancer: they all can stem from it. Most human
exposure is linked to eating fish and shellfish that live in
contaminated streams and riverbeds.”
