Animal Co-Products as Novel Electron Donors for In Situ Bioremediation
Incubations were constructed using TCE-contaminated aquifer material, and each electron donor (co-product) was added as the sole electron donor. Each animal co-product was compared to 5 controls containing common electron donors (lactate, acetate + hydrogen, and one soybean oil-based electron donor) and a sterile and unamended controls.
Lactate was the fastest of the 5 controls and as a result each animal co-product was compared to it. Of the 21 animal co-products, 17 completely dechlorinated the TCE to ethene at rates faster than lactate and 4 generated ethene at the exact same rate as lactate. In general, the more proteinaceous animal co-products were able to promote dechlorination at a faster rate than the animal coproducts with a higher fat content. All materials reduced TCE to ethene (at a 1:1 stoichiometry) faster than the commercially available soybean-based electron donor (e.g. emulsified vegetable oil). This strategy introduces a new electron donor for TCE bioremediation, which thus far is faster and more cost-effective than any electron donor reported to date.