A.L. Heard, Esq., G. Smith
Millbank.
GS/DM/46D 21st April, 1988
PROGRESS ON ASSESSMM OF SMSE ItTMI"TCAL
Ata-a-LY-vLa
There is currently a great deal of interest in an
area of
biology called biochemical and molecular
epidemiology. The
technique is based on a sample of human tissue,
usually blood,
which is examined for a number of structural or
chemical
changes. The structural changes would include
chromosome
damage whilat chemical changes include the
formation of DNA
adducts or mutations. Any observed alterations to
the genetic
material sampled would be suggestive of exposure
to a chemical
capable of interacting with DNA. The changes could
thus be
correlated with lifestyle such as exposure to
industrial
chemicals.
At the spring meeting of The British Toxicology
Society
various aspects of molecular epidemiology were
discussed
including observations on smokers. Several
speak6rs reported
differences, at both the structural and chemical
level,
between smokers and non-smokers. Chemical changes
were also
detected in the DIJA of non-smokers exposed to
environmental
tobacco smoke. Future work may well be aimed at
investigating
possible exposure of the foetus to tobacco derived
compounds.
In certain techniques applied, although changes
may be
quantified, the chemical responsible cannot be
identified. In
other specific cases however this is not the case
and certain
changes can be recognised an being due to exposure
to a
specific chemical.
The technique may thus prove to be a valuable
index of
exposure and complement monitoring data from the
environment.
An specific probes are developed it will provide
convincing
evidence of exposure to a range of compounds and
may well
contribute to the discussions on environmental
tobacco smoke.
Certainly if novel products are developed that
contain
compounds not normally found in the environment,
techniques
may well be available to monitor a sector of the
population
for level of exposure. C:)
CD
Whilst dosimetry data would be of value to the
company %10
(for example objective measurement of ETS exposure
may co
contribute to the passive smoking argument) the
danger in that
the data will be misused. Researchers will jump
from
dosimetry to risk assessment. Indeed this has
already
occurred in several publications even though the
relationshi
between the noted changes and human disease is not
underst = .
BATCo document for Province of British Columbia 28
October 1999


-2-
At present there is no scientific basis in going
beyond
the fact that molecular biology provides an
indication of
exposure to a chemical. The risk to that person's
health due
to that exposure is unknown.
G. SMITH
c.cj Dr. R. Binns
Dr. R.R. Baker
Mr. T.G. Mitchell
CD
CD
-10
00
BATCo, document for Province of British Columbia
28 October 1999