Handbook of Solvents - George Wypych - ChemTech - Ventech!

1352 Kristen I. McMartin, Gideon Koren
were employed as offset printing workers or printing trade workers. They used the solvents
for cleaning the printing machines and as diluent for printing ink. In cleaning the machines,
exposure to mixtures of nonaromatic mineral oil distillates with 0-15% aromatic compounds
may reach a high level for a short period. 40 The workers were also exposed among
other things to toluene, 1,1,1-trichloroethane, thinner, and xylene. Although the data suggest
that the findings are due to aliphatic hydrocarbons, combined solvent effects cannot be
excluded because of the multiple exposures to different solvents. 40
The mean measured level of blood toluene among the shoe workers was slightly
higher (0.51 mmol/L, 13 morning samples) than the mean among the other toluene-exposed
workers (0.38 mmol/L, 10 morning samples). 40 The shoe workers also reported use of toluene
more frequently than the other toluene-exposed workers. Industrial hygiene measurements
had been performed in three of the five work places of the shoe workers. The
concentration of toluene in air varied from 1 ppm to 33 ppm. Other solvents detected were
acetone and hexane. In two of the three shoe factories from which industrial hygiene measurements
were available, relatively high levels of hexane (33-56 ppm) were measured.
Hexane, being an aliphatic compound, may have contributed to the excess of spontaneous
abortions. 40
Comparison with IOL levels
The routine rating factor and non-routine rating factor from the Products and Chemical Divisions
range from 00 to 11 indicating no reasonable chance for exposure to some daily exposures
exceeding 50% of the OEL. The TLV-TWA for toluene is 50 ppm. 34 The Euler case
reports documented air concentrations of 298 ppm for toluene and 230 ppm for trichloroethylene.
10 Both of these air concentrations exceed current standards, but no further details of
these cases were given. Syrovadko reported a toluene exposure of 55 ppm (range 13-120
ppm), again, exceeding current standards. 36
Holmberg et al. 38 and Tikkanen 17 considered workers “substantially” exposed if their
estimated continuous exposure had been at least one-third of the current TLV concentration
or if the estimated peak exposure had reached the TLV concentration. Similarly, Ng 38 described
high concentrations of toluene (mean 88, range 50-150 ppm) exceeding current
standards. All these exposure levels for toluene exceed the current threshold limit value.
IOL toluene exposure levels are considerably lower than any value reported in the literature.
Lindbohm et al., 40 for two of four air measurements, reported concentrations of white
spirit exceeded the Finnish Threshold Limit Value (150 ppm) during the cleaning of the
printing machine. Industrial hygiene measurements were performed in three of the five
work places of the shoe workers. The concentration of toluene in air varied from 1 ppm to 33
ppm. Other solvents detected were acetone and hexane. In two of the three shoe factories
from which industrial hygiene measurements were available, relatively high levels of hexane
(33-56 ppm) were noted.
The routine rating factor and non-routine rating factor from the Products and Chemicals
Divisions for hexane isomers range from 00 to 05 indicating no reasonable chance for
exposure or minimal exposure not expected to exceed 10% of the occupational exposure
limit (OEL). The routine rating factor and non-routine rating factor from the Products and
Chemicals Divisions for n-hexane range from 00 to 07 indicating no reasonable chance for
exposure or some daily exposures between 10% and 50% of the OEL. The TLV-TWA of
n-hexane is 50 ppm or 176 mg/m 3 . 34 The TLV-TWA of other hexane isomers is 500 ppm or
1760 mg/m 3 and the TLV-STEL is 1000 ppm or 3500 mg/m 3 . 34 In comparison with the pre-