Appendix D - Dossier (PDF) - Tera

date: 20–JUL–2005
5. Toxicity Substance ID: 71–43–2
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Source: German Rapporteur
Flag: Risk Assessment
07–JUL–2005 (1195)
Result: The benzene concentration declines within a period of 10
weeks to less than 10% of this concentration (Brown and
Cheng, 2002) thus an air concentration of 12 µg/m³ can be
assumed as worst case exposure. Driving an old car, the
internal concentrations will be even lower. Benzene
exposure will increase considerably if the driving duration
is increased extensively.
Source: German Rapporteur
Flag: Risk Assessment
07–JUL–2005 (156)
Remark: Midzenski showed that even short exposure to benzene in 15
degassers of 5 days up to 3 weeks may possibly lead to
haematological alterations. 2 workers who were exposed to
benzene with concentrations above 192 mg/m³ (60 ppm) showed
WBC counts below 4.500/mm³ and 5 workers Hb values below
normal two days after exposure (Midzenski et al. 1992). A
control group was not examined. One month after exposure, 6
of the 15 workers had large granular lymphocytes in blood
smears. Blood abnormalities did not correlate with either
duration or frequency of exposure, possibly due to the
relatively brief (mean = 5 days, median = 3 days) period
of exposure.
Repeated dose toxicity
Source: German rapporteur
Flag: Risk Assessment
07–JUL–2005 (775)
Remark: ACUTE TOXICITY
The acute toxicity to humans when benzene is inhaled has
been described as being as follows:
Appendix D: Benzene SIDS Dossier
20,000 ppm 5–10 minutes exposure can give fatalities
7,5000 ppm 30 minutes exposure may be fatal
1500 ppm 60 minutes exposure causes serious symptoms
500 ppm 60 minutes exposure leads to symptoms of illness
50–150 ppm 5 hours exposure causes headache, lassitude and
weakness
25 ppm 8 hours exposure causes no clinical effect.
Signs of toxicity following exposures are CNS depression,
cardiac arrhythmia and respiratory failure resulting in
death. At lower levels of exposure CNS effects are rapidly
reversible.
The acute lethal dose of benzene to humans when ingested
has
been estimated to be about 10 mls (8.8g). The signs and
symptoms of toxicity are typically those of narcotic
solvent
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