What is Fish Bone Remediation?
Fish bones are full of calcium phosphate. When the bones are grounded up and buried in moist soil, they degrade allowing the calcium phosphate to migrate in the soil. When it comes into contact with lead particles, the calcium phosphate chemically bonds with these particles resulting in a crystalline mineral known as a pyromorphite.1 Since this secondary substance does not harm people, plants or animals even when it is consumed, powderized fish bones can lower the level of toxic lead in the soil.1
How Does Chemical Bonding Occur?
Calcium phosphate involves a beneficial feature. Its internal structure has a wide surface area which facilitates the absorption of soluble lead compounds, and in doing so bonds the two together into the crystalline mineral (pyromorphite) that will not dissolve when ingested by people and animals.1 Furthermore, the risk of soluble phosphate runoff into lakes and streams is eliminated because of the low solubility of fish bones and calcium carbonate”
Is the Process Effective?
The long term stability of the pyromorphite is demonstrated across several scientific fields including geology, palaeontology, soil chemistry, geochemistry and chemical engineering.2,3 Additionally, there is a 15-year track record of the fish bone method being successfully used to reduce toxic lead levels at firing ranges and acid mine sites.2.3 Both In-situ and laboratory tests are also showing phosphates can immobilize other potentially toxic metals, including copper, zinc, cadmium, and uranium.4
What is the Application Process?
Workers rototill 3 pounds of ground fish bones into each square foot of polluted soil. When this biological material degrades, it spreads deeper into the soil with the aid of migrating water from rain or sprinklers.
Where Do the Fish Bones Come From?
The main source of fish bones comes from commercial processing plant that make pollock into fillets, fish sticks, and artificial crab meat.
- Fighting Lead with Fish Meal, Bensozia, July 22, 2011
- PIMS Using APATITE II™: How It Works to Remediate Soil & Water, Judith Wright et al, prisim.com
- PIMS Using APATITE II™: A Field Demonstration on a Lead Contaminated Soil, Slater UK Limited and PINS NW, Inc., Cambridge University, April 13m 2005 (http://www.starnet.eng.cam.ac.uk/ConferencePresentations /session4/StarnetpresentationMar2005final.pdf)
- Phosphates for Pb Immobilization in Soils: A Review, Miretzky, Fernandez-Cirelli, Environ Chem Lett. 2008. 6(3):121–133. http://dx.doi.org/10.1007/s10311-007-0133-y