Environmental and Molecular Mutagenesis - Legacy Tobacco ...

120 1989 EMS Abstracts
Notes associated with the drinking water consumption, investigations of
the toxicological properties of MX are necessary . We now report a
convenient method for the preparation of 14C labelled MX needed in
those investigations . Bromo[1-14 C] aoetic acid (Ameraham) was first
converted to its methyl ester by general procedure with diazomethane
. Reaction of methyl bromoacetate with triphenylphosphine and
treatment of the adduct with base gave 14C labelled carbomethoxymethylenetriphenylphosFhorane
. Starting from this compound and
tetrachloroacetone [2-1 C] MX was then obtained in five steps using
the method of Padmapriya et al .l . The total yield was about 10 ~ .
The method is also suitable for the synthesis of (2-13C] MX .
REFERENCE : 1 . A .A : Padmapriya, G . Just and N .G . Lewis . Can . J . Chem .
63 (1985) 828 .
http://legacy.library.ucsf.edu/tid/clb93d00/pdf
345
TRADESCANTIA-MICRONUCLEUS TESTS ON CLASTOGENS AND IN SITU MONITORING, Te-Esiu Ma,
Institute for Environmental Management and Department of Biological Sciences, Western
Illinois University, Macomb, IL 61455 USA
Tradesoantia-Mioronucleus (Trad-MCN) bioassay is a highly sensitive test for
chemical clastogens of gaseous or liquid forms and nuclear radiatlon . Its high
sensitivity is attributed to the high degree of synchrony and fragility of the meiotio
chromosomes which are the targets of exposure . Quantitative data of chromosome damage
in terms of micronuclei frequency can be obtained from the synohronised tetrads (4cell
stage of the meiotic pollen mother cells) 36-48 hr after the exposure . The
microslides were prepared using the aoeto-carmine squash method . Since the
establishment of this bioassay, about 130 chemicals were tested . These include
carcinogene and mutagens, common beverages, common toxic compounds, non-prescription
drugs, house-hold chemicals and radioisotopee . Among these agents, 50% of them gave
positive responses at relatively low dosages (uM - mM) . Trad-MCN test is an unique
monitoring bioassay which can detect olastogens in the air on the site of pollution
without using the air condensates, and olaetogens in the polluted water directly
without using the sediments or concentrates . More than 30 different air pllution
sites and 20 sites of polluted water sources were ∎onitored in the US, Canada, Mexico
and People's Republic of China . Both surface water and ground water sources yielded
seasonal positive responses when tested through the year, Brackish water and diluted
eeawater samples from the polluted sites were all positive as compared with the
oontrol group .
346
PROFICIENCY OF TRE T~tAD-NCN 1MAGE ANI~SSIS BYST~1 FOR SCZORING MCN FfjEQ>~ENCY AND DATA
PROCESSING, T . H . Ma , J . Zu , W . Iia , I . Jong , W . Sun and G . Lin-, Institute for
Environmental Management and Depe~tment of Biological Sciences, Western Illinois
Oniveraitu, Macomb, IL 61455 USA, 'Department of Computer Science, Fudan University,
Shanghai, PRC, and 3Institute of Oceanology, Academia Sinioa, Qingdao, PRC .
Tradeecantia-Micronucleus (Trad-MCN) bioassay is an efficient short term test for
genotoxioity of pollutants . In order to increase the efficiency and to standardize the
MCN scoring process, an automated scoring system was developed using the principle of
image analysis in computer science . This assemblage is called the Tradescantia-
Micronucleus Image Analysis (Trad-MCNIA) System ." Results scored by Trad-MCNIA system
was compared with that scored by human observer for its proficiency, i .e . the accuracy
and speed . A set of low MCN frequency (lese than 10 MCN/100 tetrads) slides prepared
from EMS treated materials and a set of high MCN frequency (more than 50 MCN/100
tetrads) slide prepared from X-ray treated materials were used for this study . In low
frequency slides, The Trad-MCNIA system scored about the same value ae human
observers . In high frequency slides, MON frequencies scored by the System was lower
than that scored by human observers . This desorepanoy was corrected by increasing the
power of the objective of the microscope in the Trad-MCNIA System from 10 X to 20 I .
The MCN frequencies scored by the System was about 90x of that scored by human
observer at the present time . The scoring speed of the System was about 4 times ae
fast as that of the human observer, and the data can be processed and statistically
analyzed immediately after scores were recorded . Further improvement can be made by
upgrading the video camera and the computer speed .