Article

Evaluation of toxicity of medical devices using Spirotox and Microtox tests: I. Toxicity of selected toxicants in various diluents.

Department of Environmental Health Sciences, University of Medicine, Warsaw, Poland.
Journal of Biomedical Materials Research 05/1997; 35(1):101-5. pp.101-5
Source: PubMed

ABSTRACT Significant effort has been directed toward developing in vitro alternatives, which can be the first step of toxicity analysis. Tissue culture assays are currently the most popular in vitro tests for evaluating acute toxicity. The possibility of applying two bioassays using microorganisms in assessing the toxicity of extracts of medical devices was investigated. The Microtox test system--a luminescent bacteria toxicity test--assesses changes in light output from a luminescent bacteria, Vibrio fischeri. Spirotox used a large ciliate protozoan: Spirostomum ambiguum. The most widely used extraction solvent, 0.9% NaCl, must be concentrated up to 2% for Microtox and diluted nine times for the Spirotox test. The organic solvents ethanol, DMSO, and polyethylene glycol 400 were not toxic in either test in concentrations of 1-2%. The toxicity of reference compounds Hg, Cd, Zn, Pb, and SDS was examined in various diluents. The sequence of toxicity of the tested compounds in Spirotox and Microtox was: Hg > Cd > Zn > Pb > SDS, and Hg > Pb = Zn > SDS > Cd, respectively. Addition of organic solvents changed the toxicity of compounds tested in 60% of Spirotox tests and only in 25% of Microtox tests. Changes were low, not exceeding 100% in almost all cases. No correlation was observed between diluent and toxicant in either bioassay.

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Keywords

acute toxicity
 
cases
 
first step
 
large ciliate protozoan
 
luminescent bacteria
 
medical devices
 
Microtox tests
 
organic solvents ethanol
 
polyethylene glycol 400
 
reference compounds Hg
 
Significant effort
 
Spirostomum ambiguum
 
Spirotox
 
Spirotox test
 
Spirotox tests
 
Tissue culture assays
 
various diluents
 
Vibrio fischeri
 
vitro alternatives
 
vitro tests
 

G Nałecz-Jawecki