M E D I
C H E M
February 2001
2001 Membership
Contributions are Due
Now
Medichem 2001 Board
Elections – Call for
Candidates
In the envelope containing this
Newsletter,
Medichem
Members will receive an
invoice for the payment of the
2001 Medichem Membership
Dues. They have remained
unchanged at USD 50 per year.
Details concerning Medichem's
bank connection and possible
modes of payment can be
found on the invoice form.
The Secretary-Treasurer is
extremely grateful to those
who pay their dues promptly
and
thus
help
avoid
unnecessary cost and effort
for reminders later in the
year.
I would like to thank you
already now for your cooperation.
For those who, because of their
personal circumstances, find it
difficult to pay the full
membership
contribution,
Medichem has set aside a
limited amount of funds to
subsidise a scheme of reduced
membership
fees.
An
application must be made in
writing to the SecretaryTreasurer. The reduction is 50
per cent. The exact rules
governing the scheme can be
found in the Medichem
Handbook and are also
available from the Secretary.
This year, several Medichem
Board Members arrive at the
end of their terms of office:
Noel Humphry, Leo Miksche,
Kalle Ahlberg, Teo Popov,
Hugo Rüdiger, Abed Bin Onn
and
Andreas
Flückiger.
Furthermore, there are two
vacancies on the Medichem
Board that can be filled.
The following Board members
have stated that they are
willing to be a candidate for a
further term of office as Board
Members: Teo Popov, Hugo
Rüdiger, Abed Bin Onn and
Andreas Flückiger (who will
however hand over the
Secretariat to a successor).
According to Article 5, Section
4.1
of
the
Medichem
Constitution, every country can
only be represented by one
Board Member. As an
exception from this rule, there
can be two Board Members
from one country if one of
them holds an office.
Members are now asked to
nominate candidates for the
Board if they so wish.
Any member in good standing
can nominate a candidate. This
year, candidates for Board
membership may not be from
Canada, the Czech Republic,
Japan,
the
Netherlands,
Singapore, South Africa, the
US nor the UK.
Dr. Andreas Flückiger, Basel (Switzerland)


(continued on page 2)
Honorary President:
Prof. Dr.med. Dr.h.c. Alfred M.
Thiess
Chairman:
Dr. Noel F. Humphry
Dow Chemical (Australia) Ltd.
Kororoit Creek Road
Altona, Vic. 3018 (Australia)
Phone: +61-3-9226 3787
Fax: +61-3-9226 3798
---------------------------Secretary-Treasurer:
Dr. Andreas Flückiger
Corporate Medical Director
F.Hoffmann-La Roche Ltd.
CH-4070 Basel (Switzerland)
Phone:+41-61-688 37 38
Fax: +41-61-688 16 51
---------------------------Board Members:
Dr. R.W. Ahlberg (Finland)
Dr. A. Bin Onn (Malaysia)
Dr. L.J.N.G.M. Bloemen
(Netherlands)
Prof. M. Cikrt (Czech Republic)
Dr. W.M. Coombs (South Africa)
Dr. S. S. Guirguis (Canada)
Prof. Y. Kudo (Japan)
Dr. L. W. Miksche (Germany)
Dr. T. Wai-Hoong Phoon (Singapore)
Prof. T. Popov (Bulgaria)
Dr. A. R. Reid (U.K.)
Prof. H. W. Rüdiger (Austria)
Dr. Leslie M. Yee (USA)
Medichem Newsletter February 2001
(continued from Page 1)
All candidates must be
Medichem members in good
standing, and in addition
members in good standing of
the ICOH or agree join ICOH
before
the
election.
Furthermore, the nomination
shall only be valid if it is sent
in
along
with
written
acceptance of the nomination
from the candidate herself or
himself. Nominations must be
sent to the Secretary of
Medichem,
Dr.
Andreas
Flückiger, by mail or fax. They
must be in possession of the
Secretary no later than April
30th, 2001.
Dr. Andreas Flückiger, Basel (Switzerland)

PVC Softeners
Suspected of Causing
Allergies
Softeners of PVC-plastics are
suspected of increasing the risk
of respiratory allergies in
children. This is the finding of
a
recently
published
Norwegian study of 3000
children during two years in
Oslo. Research at the Danish
Institute of Working Life show
that some phthalates heighten
allergic reactions in mice.
PVC-plastics are used in a
large number of buildings,
mainly in floor coverings, but
also in some furniture, wall
coverings
and
other
furnishings. PVC is also found
in packaging. Floor coverings
can contain up to 40% of
phthalates.
Moisture
in
flooring is suspected of
increasing the emission of
phthalates.
The Danish Institute of
Working Life has now found
that certain mono-phthalates,
primarily DBP and DEHP,
appear both in the form of gas
and as particles in floor dust in
Danish
homes,
offices,
classrooms and day care
nurseries. During the coming
year, results from new studies
will be presented.
The number of Danish children
with allergies has, as in most
other Northwestern European
countries, more than doubled
in the past 25 years.
"The reasons for this can be
many, among them changes in
the immune system due to
changing eating habits", says
Leif Aringer, Chief Medical
Officer at the Swedish
National
Board
of
Occupational
Safety
and
Health.
The
Swedish
Chemicals
Inspectorate
has
recently
banned the use of phthalates in
toys for children under the age
of three. The Institute of
Analytical
Chemistry
at
Stockholm
University
is
planning to undertake a study
of softeners in PVC.
There is still controversy
among researchers as to the
role of phthalates in cancer and
hormone disorders.
(From the Newsletter of the
Joint Industrial Safety Council,
Stockholm, Sweden, Dec. 2000
issue).
Dr. Andreas Flückiger, Basel (Switzerland)

Fire Fighters at Risk for
Cancer?
Research undertaken in New
Zealand has identified that fire
fighters are three times more
likely to get testicular cancer
than the average male. The
study was conducted by the
Pg 2
Wellington
School
of
Medicine in conjunction with
the Institute if Environmental
Science and Research. Details
from http://www.fpaa.com.au
From: Hazmat & Enviroment
Notes,
November
2000,
submitted by
Jeff Simpson, Haztech Environmental,
Ashburton, Vic. (Australia)

26th Conference of the
ICOH in Singapore
A modest ~2000 participants
attended the 26th Conference of
the ICOH which took place
Aug
27th-Sept.
1st
in
Singapore.
The main topic of the
conference was the impact of
globalisation on safety and
health at the workplace.
The degree of industrialisation
is steadily decreasing in the socalled "industrialised" nations.
The service sector is growing
rapidly and the occupational
health issues related to this
sector
differ
from
the
traditional
occupational
diseases. "Soft factors" such as
job satisfaction are important
determinants of health at work.
Organisations
have
been
shrunk and the workload for
those
remaining
has
continuously increased. In
Finland, 8% of the working
population work 80 or more
hours a week. The average
European believes that each
week should have an extra 20
hours to enable him to do all
the things he should do. This
lifestyle has adverse effects on
exercise, and often nutrition is
not adapted to the limited
physical activity either.
Workers in this sector who are
not satisfied with their jobs are
Medichem Newsletter February 2001
often not very productive
although they show up at work
every
day.
The
term
"presenteeism"
has
been
coined for this phenomenon. In
Scandinavia, it has been
estimated that productivity
could be increased by as much
as 50% if health at work in the
broadest sense was tackled
effectively.
Large firms with traditionally
good safety and health
practices at work tend to
concentrate on what they
consider to be their "core
business". Other activities such
an maintenance and cleaning
are out-sourced to contractors.
It was suspected and has now
been confirmed that health
protection of the workforce of
these usually small contract
firms is generally inferior to
health protection that was
offered for the same jobs when
they were still integrated in a
large company.
The quality of occupational
health practices has been
influenced in different ways,
depending on the region of the
world. In the past 10 years, the
general health of the workforce
has improved in most OECD
countries as well and China
and India, but remained
unchanged or even deteriorated
in Latin America, Africa, the
Arab countries and in most
countries of the former Eastern
Block.
Women, children, the elderly
and the handicapped are
particularly vulnerable.
Among the traditional health
problems
affecting
productivity,
allergies,
affections of the musculoskeletal system and infectious
diseases are on the increase.
Whilst the terms "occupational
illness" and "occupational
disease" have been used almost
synonymously,
preference
being given to one or the other
depending on the country, the
point was made that maybe the
term "occupational disease"
should
be
used
when
describing the traditional and
well
established
health
problems arising from the
workplace
whereas
"occupational illness" would
describe those affections where
the causal link between the
affection
and
workplace
seemed plausible or even clear,
but the ailment was not
recognised by the country's
legal system as a work-related
health
impairment.
This
implies that the work-related
health problems that we see
these days in the countries of
the so-called first world often
no longer correspond to those
work-related health problems
that are legally recognised.
In most of these countries, on
paper,
the
costs
of
occupational accidents by far
exceed
the
costs
of
occupational
illnesses.
However, some countries such
as the UK have taken a closer
look at the situation and are
convinced that the real
situation is the other way
around: occupational illnesses
actually have a far greater
impact on a nation's economy
than is expressed by the figures
of recognised occupational
diseases.
Medichem was present at the
conference with a session of
proffered
papers
on
occupational health in the
chemical industry and a minisymposium on "Occupational
Pg 3
and environmental effects on
the reproduction process". Four
speakers presented papers: Rob
Taalman of CEFIC's Endocrine
Modulators Steering Group,
Ron Miller, toxicologist of
Dow Chemical, Sin-Eng Chia
of the U. of Singapore and
John Jackson of JacksonHocking in the UK.
The mini-symposium was very
well attended and feed-back
from the audience was very
positive.
ICOH will hold its next
conference in Foz do Iguaçú,
Brazil from February 23-28,
2003.
Dr. Andreas Flückiger, Basel (Switzerland)

Manganese
In
the
February
2000
Medichem
Newsletter,
a
summary was given on
research conducted at the
Chemical Industry Institute of
Toxicology (CIIT) in the US
on
the
mechanisms
of
manganese neurotoxicity.
In the past year, manganese has
been under particular scrutiny
by the occupational health
authorities in a number of
countries, in particular also the
UK. Manganese is used in the
making of steel and welding
rods, but it is also of interest to
those companies in the
chemical
industry
who
consider themselves to be
players in the field of the
health sciences. Manganese is
a trace element in animal feed
and fertilisers where it is used
in relatively large quantities.
A review of manganese
toxicity seems to indicate that
health-based
occupational
exposure limits (OELs) for this
material would have to be
Medichem Newsletter February 2001
lower than existing limits in
many countries. In many
countries, the OEL for
manganese compounds (as
Mn) is 0.5 mg/m³, but in some,
it is still as high as 5 mg/m³.
However,
epidemiological
studies show that men exposed
to workplace levels around 1
mg/m³
(inhalable
dust)
suffered from neurological
effects. A human no-effectlevel has never been clearly
identified, but is likely to be
well below 1 mg/m³, probably
also at less than 0.5 mg/m³.
The ACGIH have already had
their manganese TLV at 0.2
mg/m³ for a number of years
and this seems a reasonable
order of magnitude.
Blend plants in the feed
industry are not exactly dustfree, and even under good
conditions, exposures of 1 to 2
mg/m³ are typical.
Compliance with exposure
limits of 0.2 mg/m³ or possibly
less should be achieved
primarily by means other than
personal protective equipment.
One possibility to real this goal
would be to make the form or
manganese used less dusty.
The feed industry handles
other trace elements which can
be hazardous to health, such as
selenium and cobalt. The
quantities of Co and Se used
are much smaller than those of
Mn, and the cost of these
elements is higher than the cost
of manganese. In practice, that
means that making selenium
and
cobalt
preparations
inherently safer by bringing
them into a low dustiness
granulated form is a feasible
solution. The added cost of
granulation is relatively small
and absorbed by the market
without great difficulty.
This may not be the case for
manganese which is relatively
inexpensive and used in much
greater volumes.
It will be interesting to track
further developments in good
occupational hygiene practice
in the handling of manganese,
both the possible setting of
new and lower OELs but also
means of ensuring compliance
with these new limits.
Dr. Andreas Flückiger, Basel (Switzerland)

Occupational Toxicology
Roundtable 2000
The
historic
Mohawk
Mountain Hotel in Upstate
New York was the impressive
venue for the October 2000
Occupational
Toxicology
Roundtable,
an
informal
gathering of occupational
toxicology
and
industrial
hygiene specialists coming
mainly from the US but also
from
the
European
pharmaceutical industry.
Although the meeting is the
one of an informal group and
participation is only by
invitation, the Occupational
Toxicology Roundtable now
has a long-standing tradition
and a high reputation in the
industry.
Topics discussed are best
practises
of
occupational
hygiene in the pharmaceutical
industry, principles of setting
in-house
occupational
exposure limits for therapeutic
substances,
categorisation
systems for such compounds
and information given in those
sections of safety data sheets
that relate to health hazard
Pg 4
characterisation, occupational
handling,
toxicology
and
classification.
Since a fair amount of
professional judgement is
involved in dealing with these
subjects, exchanging views and
opinions and benchmarking is
considered indispensable.
Whilst
pharmaceutical
production
equipment
is
validated again and again for
its GMP (good manufacturing
practice, i.e. product-safety
related) performance, this not
so much the case for its
performance in terms of
industrial
hygiene.
A
manufacturer of a particular
piece of equipment can seldom
say reliably what e.g. the dust
leakage rate of his equipment
is. However, such information
would be very important to
compare
one
piece
of
equipment with another and to
decide what product can or
needs to be produced on what
sort
of
equipment.
Standardised
validation
procedures
need
to
be
developed to attain this goal.
Representatives
of
the
Occupational
Toxicology
Roundtable
are
working
together with the International
Society of Pharmaceutical
Engineers (ISPE) to develop
such standards.
Dr. Andreas Flückiger, Basel (Switzerland)

COSHH Essentials
The
so-called
COSHH
(Control
of
Substances
Hazardous
to
Health)
regulations were published in
the UK about a decade ago.
These regulation call for a
systematic approach to dealing
Medichem Newsletter February 2001
with hazardous substances at
all workplaces:
 collection
of
all
information available on
the
hazards
(the
compounds)
and
the
workplace where they are
handled
 assessment of exposures to
these hazards
 conclusion as to magnitude
of the health risk present
according to the formula:
risk = hazard x exposure
 decision on managing this
risk appropriately
It was soon recognised that
particularly small and mediumsized enterprises had great
difficulties implementing the
COSHH regulations. To assist
these companies in putting in
place the right measures to
control exposures at their
workplaces as often as possible
without specialist advice, the
UK
Health
and
Safety
Executive developed "COSHH
Essentials",
a
guidance
document that has gained a
great deal of applause and has
become a standard reference
far beyond the UK.
In
a
nutshell,
COSHH
essentials is about achieving
good
industrial
hygiene
whenever possible without
specialist advice and without
measuring.
You determine the toxicity of
the product based on its EU
risk phrases and check on the
safety data sheet whether skin
absorption might occur. This
information is then combined
with quantity handled and the
level of dustiness or volatility
of
the
product.
This
information leads up to
recommendations
for
the
engineering
controls
and
containment needed.
Sixty control guidance sheets
have been developed, each
covering a particular activity,
e.g. transfer, filling/emptying,
weighing, mixing.
"COSHH
Essentials"
is
designed to allow small
businesses to get on with
implementing
reasonable
industrial hygiene practices
without being blocked before
even starting by too complex a
task.
COSHH Essentials – Easy
Steps to Control Chemicals. 32
pages and 60 guidance sheets.
ISBN 0-7176-2421-8. Price:
about GBP 25.
Source: HSE Books. Phone
+44-1787-88 11 65, Fax: +441787-31 39 95.
Dr. Andreas Flückiger, Basel (Switzerland)
and Jeff Simpson, Haztech Environmental,
Ashburton, Vic. (Australia)

Insecticide Diazinon to
be Phased Out in the US
The
US
Environmental
Protection
Agency
has
announced plans to phase out,
by the end of 2004, the home
and garden use of the
insecticide Diazinon, the last
widely
used
pest-control
product made from the
organophosphate
class
of
chemicals, which are linked to
health risks for children.
Source: USA Today, Dec. 5,
2000 (Reuters). Sent in by
Jeff Simpson, Haztech Environmental,
Ashburton, Vic. (Australia)

Cancer Risk from
Occupational Handling
of Cytostatics
Pg 5
Many cytostatics have a
genotoxic
mechanism
of
action. They are therefore
classified as
carcinogens.
Individuals handling these
compounds in the health
sector, e.g. in hospitals, are
exposed to a certain health
risk.
The German BIA (Institute for
Occupational Safety of the
Occupational
Accident
Liability Insurance Fund – in
German:
"Berufsgenossenschaften")
reviewed the epidemiological
and toxicological literature to
determine the cancer risk from
occupational exposure to six
selected cytostatics. The risk
was calculated for 35 years of
daily handling of these
antineoplastic agents.
The agents evaluated were:
 cyclophosphamide
 melphalan
 methotrexate
 5-fluoro-uracil
 cisplatin
 etoposide
The database seems best for
cyclophosphamide. Biological
monitoring studies showed that
during the preparation of 2000
mg for patient application, a
nurse will typically absorb
anywhere between 2 and 60
mcgr of the compound. It was
calculated that these exposures
(if present 5 days a week, 35
years long) lead to an excess
cancer risk of 2:100,000 to
7:10,000.
Figures
for
melphalan
(Alkeran®) are less good, but
the cancer risk per mg
absorbed is at least 10 times
higher
than
for
cyclophosphamide. On the
other hand, therapeutic doses
for melphalan are lower than
Medichem Newsletter February 2001
those of cyclophosphamide
which
may reduce
the
exposures of the hospital
personnel to some extent.
A carcinogenic risk associated
with methotrexate has not been
demonstrated clearly, in fact, at
the doses relevant for the
workplace it may even be close
to nil. In any case, at
comparable doses, the risk is
clearly smaller than the one of
cyclophosphamide exposure.
In 1990, 5-fluoro-uracil (5-FU)
was classified in category 3 by
IARC. For once, this seems to
be an IARC classification that
is off "the other way", i.e. it
makes the compound appear
less harmful than it really is: 5FU has been shown to be an
animal carcinogen and its
major producers classify it
(voluntarily) as a carcinogen or
potential carcinogen. However,
the
carcinogenic
potency
seems to be rather low, lower
than
the
one
of
cyclophosphamide.
Cisplatin appears to be a more
potent
carcinogen
than
cyclophosphamide, but as for
5-FU, the data are insufficient
to quantify the difference.
Etoposide: This compound as
been well studied in terms of
causing secondary leukaemia
after full therapeutic courses.
The excess risk (per mcgr of
compound absorbed) for
hospital staff handling the
material was estimated to be
similar to the risk associated
with
cyclophosphamide,
maybe slightly higher.
Assessing the acceptability of
the calculated risks is no
longer a scientific matter.
OSHA is cited as having stated
that an excess risk of 1 case in
1000 working lives is "clearly
significant". In making this
statement, OSHA quotes a
Supreme Court decision in
which an acceptable (cancer)
risk at the workplace would be
located somewhere between 1
in 1000 and 1 in a billion (109).
In
the
Netherlands,
an
agreement between employers
and workers representatives
was reached. According to this
agreement, the excess risk for
the whole working life,
calculated by means of linear
extrapolation, should as a
target be lower than 4 in
100,000, but should never
exceed 4 in 1000.
If individuals were exposed
during their whole workinglives at TRK level (German
technically-based occupational
exposure guidance levels for
industrial carcinogens), it is
estimated that excess cancer
incidences would be in the
range of several cases per 1000
or even per 100.
Further details (in German):
Arbeitsmedizin,
Sozialmedizin,
Umweltmedizin, 36 (2001),
41-45.
Dr. Andreas Flückiger, Basel (Switzerland)


Pg 6
make up 48% of the labor
force and men 52%. In 1998,
the respective shares were 45
and 55%.
In 1950, about one in three
women participated in the
labor force. By 1998, nearly 3
of every 5 women of working
age were in the labor force.
Among women over the age of
16,
the
labor
force
participation rate was 34% in
1950 compared with 60% in
1998.
Changes in labor force
participation varied by age
group. The biggest increase in
labor force participation was
among those age 25-34 – from
a level of 34% in 1950 to 76%
in 1998. Also, in 1950, women
between 16 and 24 years of age
had the highest labor force
participation rate (44%); in
1998 women age 35-44 had the
highest rate (77%), followed
closely by those age 25-34 and
those 45-54 (both 76%). The
only age group to experience a
decline
in
labor
force
participation between 1950 and
1998 were those age 65 and
over. For more information,
consult the BLS website http://
www.bls.gov/
Dr. Andreas Flückiger, Basel (Switzerland)
Women's Share in US
Labour Force to Grow
Further
According to US Bureau of
Labor Statistics (BLS), overall
labor force participation rates
will continue to rise among
women and edge down among
men between 1998 and 2008.
As a result, women's labor
force growth should be faster
than men's. As more women
are added to the workforce,
their share will approach that
of men. In 2008, women will


Trichloroethylene to be
Phased Out as Cold Dry
Cleaning Agent in
Australia
In Australia, tichloroethylene
has been classified as a
category 2 carcinogen (likely
to cause cancer in humans) and
a class 3 mutagen (possible
genetic damage to humans)
since March 2000.
Medichem Newsletter February 2001
For this reason, the National
Industrial
Chemical
Notification and Assessment
Council is following up the
adoption
of
the
recommendations to phase out
trichloroethylene as a cold
cleaning solvent by the end of
2002. Trichloroethylene can
still be used for hot vapour
degreasing
and
cleaning
provided the vapour degreasing
equipment
meets
the
performance
standards
to
contain
and
minimise
emissions. www.nohsc.gov.au/
nicnas
Sent in by
Jeff Simpson, Haztech Environmental,
Ashburton, Vic. (Australia)


More Deaths in the US
at the Beginning of Each
Month
A peculiar phenomenon has
been observed in the US for
quite some time: the fact that
the number of deaths tended to
decrease in the course of each
month. On the average of the
years 1973 to 1988, it was
found that for each 100 deaths
during the last week of a
month, 114 persons died in the
first week of the following
month.
An investigation showed that
among the causes of death at
the beginning of the month,
drug
abuse,
alcohol
consumption, homicide and
suicide were particularly more
common than towards the end
of the month. The authors
conclude that this observed
phenomenon may be linked to
poverty. At the end of each
month, salaries are paid, but
also welfare payments are
made. It is assumed that
toward the end of the month,
certain
groups
in
the
population run out of money
and when checks are received,
more money is spent on
alcohol and drugs, leading to a
higher death rate. Source:
Deutsches Aerzteblatt, 97 (22),
2000, based on Phillips, D.P. et
al: An increase in the number
of deaths in the United States
in the first week of the month.
N Eng J Med 1999; 341: 9398. Sent in by
Prof. Dr. Dr. Alfred M. Thiess,
Ludwigshafen-Oggersheim (Germany)


Maternal Smoking
Increases PCB Burden
in Newborns
Polychlorinated
biphenyls
(PCBs) and hexachlorobenzene
(HCB) are environmental
contaminants that can be found
in traces almost everywhere.
They are considered to be
teratogenic and carcinogenic.
In particular, simultaneous
administration
of
these
compounds
and
tobaccospecific carcinogens shows
tumour-promoting affects in
animal experiments. Whilst it
was recently demonstrated that
certain
tobacco-specific
carcinogens cross the placental
barrier, nothing was known as
to the antenatal PCB and HCB
burdens.
Serum samples of eighty
newborns
were
collected
before the first feeding. The
serum samples were analysed
for PCB cogeners 28, 52, 101,
138, 153 and 180 as well as for
HCB.
For the statistical evaluation of
the results, three groups were
formed: smoking mothers,
non-smoking
mothers
Pg 7
passively exposed to tobacco
smoke
and
non-smoking
families.
The children of smoking
mothers showed the highest
PCB and HCB levels and the
lowest levels were found in the
children of the non-smoking
families. The differences were
statistically significant
(p
<0.01) for HCB, for PCB 138
and for the sum of PCBs 138,
153 and 180.
Epidemiological studies on an
association
of
maternal
smoking and childhood cancer
have so far shown ambiguous
results. From: Lackmann, G.M.
et al: Parental smoking and
neonatal serum levels of PCBs
and HCB. Pediatr Res 2000;
47: 598-601.
Dr. Andreas Flückiger, Basel (Switzerland)


Skin Absorption of
Vaporous Solvents
The dermal absorption rates of
vaporous
1,1,1-trichloroethane (111tri), trichloroethene (tri), tetrachloroethene
(tetra), hexane (hex), toluene
(tol) and m-xylene (xyl) were
determined
in
human
volunteers. The absorption data
were used for the validation of
two published models for the
prediction of non-steady-state
skin
absorption.
Five
volunteers were dermally
exposed on an area of about
1000 cm2 (forearm and hand)
for 20 or 30 minutes. An
inhalation exposure with a
known dose rate served as a
reference. Using the solvent
concentrations in exhaled air,
measured after both inhalation
and dermal exposure, the
maximum absorption rate into
Medichem Newsletter February 2001
the blood, and the average
absorption rates into the skin
throughout the exposure, were
determined using the linear
system dynamics model. The
absorption rates into the skin,
normalised
for
exposure
concentration, amounted to
0.021 cm/h (111tri), 0.049
cm/h (tri), 0.054 cm/h (tetra),
0.013 cm/h (hex), 0.14 cm/h
(tol) and 0.12 cm/h (xyl). The
maximum absorption rates into
the blood ranged from 0.005
nmol/h for 111tri and hex to
0.05 nmol/h for tol.
The ratios between predicted
and experimental values of the
absorption rates into the skin
ranged, for the model of Cleek
and Bunge, from 0.3 (hex) to
1.1 (tri and tetra), and for the
model of Wilschut and Ten
Berge, from 1.1 (hex) to 4.7
(xyl). The linear system
dynamics model allowed to
calculate not only the total
amount absorbed by the skin
but also the maximum
absorption rate into the blood.
The steady-state absorption
rate, usually described by
permeability constants, will be
below the absorption rate into
the skin and above the
absorption rate into the blood.
The skin absorption rates
predicted by the models
showed good agreement with
the experimental values. A
comparison of the estimated
whole-body skin uptake with
the inhalatory uptake from the
same atmosphere revealed that
the dermal uptake contributed
from 0.1% (hex) to 1% (tol and
xyl) to the total uptake.
(Kezic, S. et al: Skin
absorption of some vaporous
solvents in volunteers. Int Arch
Occup Env Health 2000, 73
(6), 415-22.
Dr. Andreas Flückiger, Basel (Switzerland)

Welcome to New
Members
Prof. Margarita Koleva, Dept.
of Hygiene, Ecology and
Occupational Health, Sofia,
(Bulgaria)
Prof.
Zhivka
Halkova,
National Centre of Hygiene,
Medical
Ecology
and
Nutrition, Sofia (Bulgaria)
Dr. Javier Cristián Amherd,
BASF, Rosario, Santa Fé
(Argentina)
Ms. Tania Antill, Sasol,
Johannesburg (South Africa)
Dr. Claude Witz, Givaudan
and Firmenich Ltd., Geneva
(Switzerland)
Dr. André Veneman, Akzo
Nobel,
Arnhem
(The
Netherlands)


Forthcoming Events
June 10-13, 2001, Göteborg
Exposure Assessment in
Epidemiology and Practice
Co-organised by the ICOH SC
on Industrial Hygiene. Info:
X2001,
Department
of
Occupational Medicine, St.
Sigfridsgatan 85, S-412 66
Göteborg (Sweden). Fax: +4631-40
97
28.
e-mail:
[email protected]
June 11-13, 2001, Toulouse
(France)
Dust, Fumes and Mists in the
Workplace
Organised by ISSA, Chemistry
Section. Topics: Biological
effects of and assessment and
reduction of exposure to
Pg 8
particulate pollutants, Ultrafine
particles, specific dusts. Info:
INRS,
Colloque
AISS
Puossières 2001, 30 rue Olivier
Noyer, F-75680 Paris Cedex
14 (France). Fax: +33-140 44
30 99. e-mail: [email protected]
Sept. 4-6, 2001, Prague
XXIX Medichem
Info: Congress Secretariat
Agentura Carolina, Medichem
2001, PO Box 45, Albertov
7/3A, CZ-128 01 Praha, Fax:
+420-2 2491 8681. Internet:
www.carolina.cz/medichem
2001/index.htm
The second announcement
and the registration papers
are currently in print and
will be sent out to all
members very shortly.

November 3-5, 2001, Brussels
(Belgium)
World
Occupational
Exposure Values Symposium
Presented by IOHA & ACGIH.
Info: ACGIH Worldwide, 1330
Kemper
Meadow
Dr.,
Cincinnati, OH 45240 (USA).
Fax: +1-513-742-3355. e-mail:
[email protected].
Internet:
http://www.woev.org
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