Handbook of Solvents - George Wypych - ChemTech - Ventech!

20.3 Pregnancy outcome following solvent exposure 1349
Chemical Reference Literature Exposure Levels IOL Exposure Levels
Styrene
Toluene
Saamanen 45
Harkonen 46
Euler 10
Syrovadko 36
Ng et al. 39
70-100 ppm
20-300 ppm
298 ppm
13-120 ppm
50-150 ppm
IOL: Imperial Oil Limited, OEL: Occupational Exposure Limit
“no reasonable chance for exposure
to minimal exposure not expected
to exceed 10% OEL”
TLV-TWA: 50 ppm, TLV-STEL:
100 ppm
“no chance for exposure to some
daily exposure exceeding 50% of
the OEL” TLV-TWA: 50 ppm
Results and discussion
Six studies were found that quantified toluene concentrations. The countries that reported
these observations included Germany, Russia, Finland and Singapore. In general, IOL toluene
levels are lower than those reported in the literature.
A few case reports of malformations in association with toluene exposure have appeared.
Euler 10 reported 2 cases of multiple malformations where the anomalies were similar
in children born to women who worked in shoemaking and were exposed to a soling
solution containing toluene and trichloroethylene. The average concentration of toluene in
the air was 298 ppm (1.12 mg/l) and of trichloroethylene 230 ppm (1.22 mg/l). No further
details of these cases were given.
Toutant and Lippmann 28 reported a single case of adverse pregnancy outcome in a
woman addicted to solvents (primarily toluene). The woman, aged 20 years, had a 14-year
history of daily heavy solvent abuse. On admission to the hospital, she had ataxia, tremors,
mild diffuse sensory deficits, short-term memory loss, blunted affect, and poor intellectual
functioning compatible with severe solvent and/or alcohol abuse. The male child born at
term was microcephalic with a flat nasal bridge, hypoplastic mandible, short palpebral fissures,
mildly low-set ears, pronounced sacral dimple, sloping forehead and incoordination
of arm movements with unusual angulation of the left shoulder and elbow. There was a poor
sucking reflex and movements were jerky at 2-4 days of age, although this improved spontaneously.
The authors of this report point out the similarities between this case and fetal alcohol
syndrome and suggest that there may be an analogous “fetal solvent syndrome” or
that excessive solvent intake may enhance the toxicity of alcohol.
Syrovadko 36 studied the outcome of pregnancy in a substantial number of women exposed
to toluene. Toluene exposure averaged 55 ppm (range 13-120 ppm). The factory had
its own maternity section where the women had their deliveries. Records of labor and newborns
were examined for 133 women in contact with toluene and for 201 controls from the
factory offices. There was no detectable effect on fertility. In the exposed group, records
showed a mean pregnancy rate of 3.2/worker compared with 2.6/worker in the control
group. There were no significant differences between exposed and control groups in the
mortality or adverse effects on the newborn.
In the Finnish study of Holmberg 37 on central nervous system defects in children born
to mothers exposed to organic solvents during pregnancy, 3 of the cases were exposed to toluene,
or toluene in combination with other solvents. In one case with hydranencephaly and
death 24 days after birth, there was exposure to toluene, xylene, white spirit and methyl
ethyl ketone from rubber products manufacture. The second case had multiple abnormali-