British Journal ofIndustrial Medicine, 1976, 33, 106-107
Ostwald solubility coefficients of some
industrially important substances
R. J. SHERWOOD
Colt International Ltd, Havant, Hampshire
Sherwood, R. J. (1976). British Journal ofIndustrial Medicine, 33, 106-107. Ostwald solubility
coefficients of some industrially important substances. Solubility coefficients in blood for
benzene, toluene, and xylene were determined as 6-5, 16, and 42 respectively. In lard and
olive oil, which were taken to represent human fat, corresponding values were about 450,
1300,and3900.The coefficient for vinyl chloride in lard and olive oil was 20;the value in blood
was too low to be determined by the technique used. Trichloroethylene, used as a marker, was
found to have a coefficient in lard of 660, and in olive oil of710, rather lower values than have
been accepted for fat.
To study uptake and elimination of anaesthetic
gases, analogue computer models of the processes in
the body have been developed (Mapleson, 1963),
and have been used for assessing occupational
exposures (Fiserova-Bergerova and
Recently, refinements have been made to such
models, and these have been adapted to digital
computing methods (Mapleson,
Bergerova, Vlach, and Singhal,
mathematical modelling ofmetabolic processes, such
as the production of phenol in urine after exposure
to benzene, has not yet been achieved.
Essential to such modelling is a knowledge of
Ostwald solubility coefficients as these define the
different compartments of the body. Recently, a
compendium of known determinations was pub-
lished (Steward et al., 1973) but this excluded the
importance. To provide information for the mathe-
1972a) some new determinations of
coefficients have been made and
concentrations over human blood and oil containing
known amounts of benzene (Sherwood, 1972b), a more
definitive series of measurements was made using the gas
determinations of vapour
described by Lowe and
To represent human fat, chromatographic columns were
prepared which comprised either 65 mg lard or 70 mg
olive oil adsorbed on about 4 5 g M & B Embacel support
(120-150 mesh, acid-washed kieselguhr) in 91P5 cm x 6A4
The columns were maintained at a constant tempera-
ture of 37°C with a nitrogen carrier gas flow of about 53
ml/min. A flame ionization detector was used, and
methane and trichloroethylene were used as markers.
Some difficulties were met in adsorbing the blood
sample on the Embacel support and in obtaining sharp
peaks. It was found essential to saturate the nitrogen with
water vapour at room temperature to maintain the
condition of the blood. Because the water content was
variable, the precise loading of blood was not known.
Absolute values of the solubility coefficients (K) for
lard and olive oil were determined from the equations
used by Lowe and Hagler (1969):
where VRO = gas retention volume
VGO= retention volume of inert marker
= density of lard or olive oil at column
WL = weight of lard or olive oil on column
VRO= 1-5tRFc[(PI/Po)2- 1]
where tR = time from injection to peak height
FC= carrier gas flow
Ostwald solubility coefficients ofsome industrially important substances
RESULTS FOR FIVE SUBSTANCES AND MARKER
Ostwald solubility coefficients
Pi = absolute pressure at column inlet
Po = absolute pressure at column outlet.
Absolute values for blood could not be determined
directly as WL was unknown. They were deduced
from the retention times relative to trichloroethylene,
for which an absolute value of 9 0 was assumed
(Steward et al., 1973).
The results for five substances are shown in the
The solubility coefficients for the aromatic hydro-
carbons increase with molecular weight, and no great
differences are seen between those in lard and olive
oil, so human fat is probably well represented. The
ratios between the coefficients for the aromatic
hydrocarbons and trichloroethylene in lard and oil
are consistent with those in blood.
The check measurement ofthe solubility coefficient
of chloroform in blood (8-2) is effectively identical
with the recommended value of 8-0 (Steward et al.,
1973). The absolute values for trichloroethylene of
656 in lard, and 714 in olive oil, are lower than the
recommended value of 943 derived from measure-
ments in soya bean oil by Soucek (1955), but in
close agreement with that ofLowe and Hagler (1969)
who reported 634 and 740 in human fat.
The values for benzene are lower than the pre-
liminary values reported (Sherwood, 1972a) which
corresponded to 9-2 for blood, and 890 for fat. That
for benzene in blood is in close agreement with the
values of 6-58 derived by Schrenk et al. (1941) for
dogs, and of 7-76 determined by Teisinger and
Skramovsky (1947) for man.
This work was undertaken while the author was with
Esso Europe Inc. Grateful acknowledgement is made to
Mr F. W. G. Carter of Esso Research Centre, Abingdon,
for undertaking the gas chromatographic measurements,
and to Professor W. W. Mapleson of the Welsh National
School of Medicine for helpful discussions.
Fiserova-Bergerova, V. and Cettl, L. (1972). Electric
analogue for uptake, metabolism, and excretion of
lipid soluble solvents in man (in Czechoslovakian).
Pracovni lekarstvi, 24, 56-61.
Vlach, J., and Singhal, K. (1974). Simulation and
prediction of uptake, distribution, and exhalation of
organic solvents. BritishJournalofIndustrialMedicine,
Lowe, H. J. and Hagler, K. (1969). In Gas Chromatography
in Biology and Medicine, edited by R. Porter, pp.
86-112. Churchill, London.
Mapleson, W. W. (1963). An electric analogue for uptake
and exchange of inert gases and other agents. Journal
ofApplied Physiology, 18, 197-204.
(1973). Circulation-time models of the uptake of
inhaled anaesthetics and data for quantifying them.
British Journal ofAnaesthesia, 45, 319-334.
Schrenk, H. H., Yant, W. P., Pearce, S. J., Patty, F. A.,
and Sayers, R. R. (1941). Absorption, distribution and
elimination of benzene by body tissues and fluids of
dogs exposed to benzene vapor. Journal of Industrial
Hygiene and Toxicology, 23, 20-34.
(1972a). Comparative methods of
biologic monitoring of benzene exposure. In Pro-
ceedings of the 3rd Annual Conference on Environ-
mentalToxicology,AMRL-TR-130. Aerospace Medical
Research Laboratory, Wright Patterson Air Force
Base, Ohio, USA.
(1972b). Benzene: the interpretation of monitoring
results. Annals of Occupational Hygiene, 15, 409-423.
Soucek, B. (1955). Distribution coefficient of trichloro-
ethylene (in Czechoslovakian). Pracovni lekarstvi,
Steward, A., Allott, P. R., Cowles, A. L., and Mapleson,
W. W. (1973).
anaesthetics for water, oil, and biological media.
British Journal ofAnaesthesia, 45, 282-293.
Teisinger, J. and Skramovsky, St. (1947). Sur la courbe
de saturation du benzene dans le sang.
Archives des MaladiesProfessionales de Medicine del
Travail et de Securite Sociale, 8, 257-261.
Received for publication 9 April 1975
Accepted for publication 13 January 1976