Appendix D - Dossier (PDF) - Tera

date: 20–JUL–2005
5. Toxicity Substance ID: 71–43–2
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Exposure
No detailed exposure data are presented. The full shift TWA
exposure to benzene is stated as 0.017 ppm to 0.191 ppm,
with an overall mean of 0.112 ppm and a median of 0.033 ppm.
Styrene, toluene and xylene were stated to be below 1 ppm.
Pregnancy parameters
The overall mean(SD) birth weight for this group was
3427(441) g. The gestational age had a near normal
distribution, with a mean(SD) of 39.9(1.4) weeks. The mean
birth weight was 82 g lighter, and the mean gestational age
0.2 weeks shorter, for the group exposed to benzene in
comparison to the controls.
When the data were adjusted for gestational age, benzene
exposure (–58 g, p = 0.044) and perceived work stress (–84
g, p = 0.026) were associated with a significant reduction
in birth weight. Exposure to noise and other hazards was
without significant effect.
Multivariate analysis demonstrated a significant interaction
between benzene exposure and workplace stress. Adjusted mean
birth weight was 3445 g for the control, 3430 g for those
with only exposure to benzene, 3426 g for those with only
work stress, and 3262 g for those with exposure to both
benzene and work stress. The group with both exposures
showed a 183 g reduction in birth weight relative to the
controls.
Source: A.K. Mallett Surrey
Conclusion: The authors conclude that low level exposure to benzene and
work stress interact to reduce birth weight.
25–APR–2002 (188)
Type: other: human menstrual cycle
Method: Subjects
The study population comprised newly–wed women and nonparus
married women aged 20 – 40 yr who worked for the Beijing
Yanshan Petrochemical Corporation. 1408 women with
occupational exposure to benzene, toluene, styrene and
xylene (BTSX) were recruited to the study, which ran between
1994 and 1998.
Appendix D: Benzene SIDS Dossier
Exposure assessment
Each woman’s exposure to organic solvents was determined by
an evaluation of the production/processing activity underway
in her place of work. She was classified as exposed if a
particular aromatic solvent (BTSX) was used in the vicinity
where she worked, otherwise she was classified as unexposed.
The number of years of exposure to a specific solvent was
also assessed by questionnaire, as was potential exposure to
other potential reproductive toxicants.
Assessment of menstrual patterns
Information on each subject’s menstrual pattern in the year
before enrollment into the study was assessed by
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