Microtox EC50 values for drinking water by-products produced by ozonolysis

Chou, Chin C.; Hee, Shane S. Que

doi:10.1016/0147-6513(92)90084-g

Cited by 14 publications

(9 citation statements)

References 17 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…Microtox@ data at 5, 15,25 minutes show the same distribution and optima. The response times selected were based on the kinetics of the luminescence decay (21,22). The ionic strength versus relative luminescence ratio in Fig.…”

Section: Methodsmentioning

confidence: 99%

See 1 more Smart Citation

Separation of pH, dilution, lonic strength and chemical matrix effects for biological monitoring of urines with the Microtox® test using nicotine, cotinine and reference urines

Chou

Hee

1993

J. Biolumin. Chemilumin.

Self Cite

View full text Add to dashboard Cite

The aim was to investigate the factors influencing light emission from Photobacterium phosphoreum in the Microtox test to interpret bioassay results for urine. Four reference urines were assessed as reference materials for the bioassay. Nicotine and cotinine were investigated as urinary markers for tobacco exposure. The optimum luminescence conditions were: 1.85%-3.25% NaCl, 0.33-0.58 mol/L ionic strength, and pH 5.8-6.7. Low pH values and high concentration of toxic trace metals were important factors in this study. Unexpected toxicity for a Standard Reference Material was attributed to zinc contamination. Nicotine and cotinine together exhibited antagonistic effects in 2% saline but this could not be observed in the urines because of substantial urine toxicity. Thus practical urinary biological monitoring with the Microtox test necessitates excretion of metabolites and compounds that are much more toxic than the urine components. Also, separation of the effects of physical factors like pH, ionic strength and dilution is essential before chemical toxicity effects can be assigned. This is the first report of Microtox EC50 values for nicotine and cotinine. The results have application to environmental samples since analyses are often uncontrolled relative to pH, ionic strength and dilution.

show abstract

Section: Methodsmentioning

confidence: 99%

“…Our procedure for the MicrotoxtRJ bioassay has been described elsewhere (21). To summarize, 0.5 mL of MOAS was added to 5 mL of reconstituted urine, and the aliquots diluted stepwise with 2% NaCl (Microtoxi@ Diluent).…”

Section: Microtox@ Bioassaymentioning

confidence: 99%

Separation of pH, dilution, lonic strength and chemical matrix effects for biological monitoring of urines with the Microtox® test using nicotine, cotinine and reference urines

Chou

Hee

1993

J. Biolumin. Chemilumin.

Self Cite

View full text Add to dashboard Cite

show abstract

“…To make the insoluble compounds bioavailable, aldehydes beyond C 3 , carboxylic acids beyond C 7 , and ketones beyond C 9 were solubilized in 0.45% methanolic growth medium. Table I gives the 25 min EC 50 values for each class of compound (5). From C l to C 7 , the toxicity for compounds of the same number of carbon atoms decreased in the order carboxylic acid, aldehyde, and ketone.…”

Section: Acute Toxicity Experimentsmentioning

confidence: 99%

“…The aims of the present paper are to review the author's research with bioluminescent bacteria in assessing the acute toxicity of simulated biological media like urine and saliva in 5.0-mL volumes using Photobacteriumphosphoreum (4)(5)(6)(7)(8) and genotoxicity with a dark mutant of Vibrio fischeri in O.200 mL volumes (2). The measurements were performed on the Microtox Model 500 Analyser (Microbics Corp., Carlsbad, CA) at 15°C for the acute test, and at 27°C for the genotoxicity test.…”

mentioning

confidence: 99%

Mutagenesis and Acute Toxicity Studies on Saliva-Leached Components of Chewing Tobacco and Simulated Urine Using Bioluminescent Bacteria

Hee¹

1997

ACS Symposium Series

Self Cite

View full text Add to dashboard Cite

“…The bacterium is standardized by storing and transporting it as a freeze-dried powder that is reconstituted into a saline growth medium at 153C at the time of the analysis. Our research group has published on the variables that a!ect the test Que Hee, 1992, 1993;Chen and Que Hee, 1995) and on some applications (Chou and Que Hee, 1992, 1993, 1994aChen and Que Hee, 1995;Que Hee, 1997). The present study explores the dependence of light output on viable cell number, the e!ects of dust on the Microtox test and cell viability, how the viability of the cells is a!ected after spills, and how spills can be sampled.…”

Section: Introductionmentioning

confidence: 96%