MSDS

Material Safety Data Sheet
Version: 1.4
12/09/2009
M90015
Silicone Rubber Sealant
Page 6/8
SKIN IRRITATION
no data available
EYE IRRITATION
no data available
MUTAGENICITY
Unknown
OTHER EFFECTS OF OVEREXPOSURE
This product contains methylpolysiloxanes which can generate formaldehyde at approximately 300
degrees Fahrenheit (150'C) and above, in atmospheres which contain oxygen. Formaldehyde is a
skin and respiratory sensitizer, eye and throat irritant, acute toxicant, and potential cancer hazard. A
MSDS for formaldehyde is available from Momentive., Methanol released during curing., Ammonia
released during curing., Octamethylcyclotetrasiloxane Ingestion: Rodents given large doses via oral
gavage of octamethylcyclotetrasiloxane (1600 mg/kg day, 14 days) developed liver weights relative to
unexposed control animals due to hepatocellular hyperplasia (increased number of liver cells which
appeared normal) as well as hypertrophy (increased cell size). Inhalation: In inhalation studies,
laboratory rodents exposed to octamethylcyclotetrasiloxane (300 ppm five days/week, 90 days)
developed increased liver weights in female animals relative to unexposed control animals. When the
exposure was stopped, liver weights returned to normal. Microscopic examination of the liver cells did
not show any evidence of pathology. Inhalation studies utilizing laboratory rabbits and guinea pigs
showed no effects on liver weights. Inhalation exposures typical of industrial usage (5-10 ppm)
showed no toxic effects in rodents. Range finding reproductive studies were conducted (whole body
inhalation, 70 days prior to mating, through mating, gestation and lactation) with
octamethylcyclotetrasiloxane (D4). Rats were exposed to 70 and 700 ppm. In the 700 ppm group,
there was a statistically significant reduction in mean litter size and in implantation sites. No D4
related clinical signs were observed in the pups and no exposure related pathological findings were
found. Interim results from a two generation reproductive study in rats exposed to 500 and 700 ppm
D4 (whole body inhalation, 70 days prior to mating through mating, gestation and lactation) resulted in
a statistically significant decrease in live mean litter size as well as extended period of off-spring
delivery (dystocia). These results were not observed at the 70 and 300 ppm dosing levels. Preliminary
results from an ongoing 24-month combined chronic/oncogenicity study in rats exposed to 10, 30, 150
or 700 ppm D4 showed test-article related effects in the kidney (male and female) and uterus of rats
exposed for 12 to 24 months. These effects include increased kidney weight and severity of chronic
nephropathy, increased uterine weight, increased incidence of endometrial cell hyperplasia, and an
increased incidence of enometrial adenomas. All of these effects were limited to the 700 ppm
exposure group. The relevance of this data to humans is unclear. Further studies are ongoing. In
developmental toxicity studies, rats and rabbits were exposed to octamethylcyclotetrasiloxane at
concentrations up to 700 ppm and 500 ppm, respectively. No teratogenic effects (birth defects) were
observed in either study.
12. ECOLOGICAL INFORMATION
ECOTOXICITY
no data available