Relevant Publications

A list of relevant scientific publications and patents is available on the Harvard Bioscience/Mitoscan web page.

Aquatox Research personnel have also engaged in research regarding the development of the Mitoscan assays as described below.

A study assessing the intralaboratory precision of the in vitro submitochondrial particle (SMP) electron transfer (ETr) and reverse electron transfer (RET) assays was undertaken using the standard reference toxicants, pentachlorophenol (PCP), sodium dodecyl sulfate (SDS) and zinc sulfate 7-hydrate (ZnSO4 7H2O). One to three trials of each assay were manually conducted daily for at least five days with each toxicant using commercially available sources of particles and reagents. Composite coefficients of variation (CVs) for the ETr assay ranged from 20.6% for ZnSO4 to 29.3% for PCP (n>15). Composite CVs for the RET assay ranged from 6.5% for SDS to 16.5% for PCP (n>15). Comparison of intralaboratory results with data available in the literature demonstrate that the precision of both of these SMP assays is comparable to that of the more common in vivo, whole organism bacterial, invertebrate, and fish toxicity tests.

While studies assessing the toxicity of environmental contaminants to aquatic organisms date back to the early 1900s, the use of toxicity testing as a tool for monitoring the environmental acceptability of discharges from wastewater treatment and manufacturing facilities to surface waters (i.e. rivers, lakes and oceans) did not begin to evolve until the 1970s. One of the primary motivating factors behind the development of biological monitoring, or biomonitoring, was the manufacture of exponentially increasing numbers of new chemicals for which analytical procedures were generally lacking. Biomonitoring was viewed as an approach to detect the presence of potentially toxic chemicals in facility discharges without necessarily having to identify the contaminants at that stage of the assessment. Additional advantages included the reduced expense associated with biologically testing significantly greater numbers of samples in comparison with analytical procedures. This approach also focused on only biologically available forms of the chemicals in solution reflecting any interactive effects (synergistic or antagonistic) that might be occurring among contaminants within a complex sample….

Abstract

The submitochondrial particle (SMP) assay employs processed mammalian mitochondria to assess the toxicity of chemical contaminants in aqueous solutions. SMP and associated reagents are commercially available to support two individual procedures, the Electron Transfer (ETr) and Reverse Electron Transfer (RET) assays. The objective of this study was to assess the effect of storage temperature on SMP activity. One RET and one ETr assay were conducted with sodium dodecyl sulfate on each of two vials of particles stored at -20oC and -80oC at periodic intervals over a six-month span. Results demonstrated that SMP could remain active in either assay through six months of storage at either temperature. However, there were isolated vials of particles stored at -20oC that exhibited unacceptable reductions in activity for both the ETr and RET assays that was not related to storage duration. These results were used to develop guidance in assessing the acceptability of particle activity in SMP assays.