Modeling interactions of toxic metals with suspended bacterial cells, extracellular polymer and biofilms in a simulated freshwater environment
- Cornell Univ., Ithaca, NY (United States)
The transport of transition metals in aquatic environments is governed by their interactions with suspended and adherent biological materials and with colloidal and deposited metal oxides. These interactions were investigated using a laboratory biofilm reactor system containing a pure culture of a single bacterial species (Pseudomonas cepacia) to exemplify biological factors influencing trace metals. Use of controlled conditions allowed for development of mechanistic models to describe bacterial growth and attachment, extracellular polymer production, and biofilm accumulation as well as the interactions of each of these phases with trace metals (exemplified by lead). Lead binding to each component of the system was characterized by determining adsorption isotherms in separate experiments. Integration of the biological model with lead binding data and a chemical equilibrium program (MINEQL) to determine speciation provided a general mechanistic model to predict lead transport and distribution. The most significant factors influencing lead distribution in these experiments were lead binding to biofilms, which consisted of up to 80% extracellular polymer and lead binding to iron oxide deposits.
- OSTI ID:
- 126546
- Report Number(s):
- CONF-950402--
- Country of Publication:
- United States
- Language:
- English
Similar Records
Trace metal interactions with microbial biofilms in natural and engineered systems
Interactions of microbial biofilms with toxic trace metals; 2: Prediction and verification of an integrated computer model of lead (II) distribution in the presence of microbial activity