is that it should be able to
take up and sequester the pollutant in harvestable aboveground
tissues and must also be able to tolerate the presence of the pollutant
while maintaining normal growth and development. In some
phytoextraction efforts a hyperaccumulating plant species is utilized.
A metal hyperaccumulator plant is typically defined as a
plant species that accumulates a metal to a concentration in the
aboveground tissues 100-fold higher than what is normally
observed for plants. The accepted criteria for heavy metal hyperaccumulating
plants are at least 100 mg/kg (0.01% dry wt.