No. 1031 - Miljøstyrelsen

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3 Health evaluation of siloxanes
3.1 Data on toxicity of siloxanes
Information about the toxicity of the siloxanes has been searched in open databases
on the Internet and also as a general search based on CAS number,
chemical name or just the term “siloxanes”, e.g. in combination with individual
terms relevant to toxicity testing and results, using different search engines
and meta search engines. Contacts to a few siloxane research university environments
have pointed to the same literature as identified from searching the
Internet.
As a first step in the data search, a preliminary database screening was carried
out for decamethyl cyclopentasiloxane (Annex 6).
The data search has included the following general databases with information
on chemical substances and their toxicological effects:
• RTECS;
• TOXNET: TOXLINE, CCRIS, HSDB, IRIS, GENE-TOX, DART /
ETIC;
• MEDLINE;
• ScienceDirect (Journals);
• NTP;
• ASTDR.
The screening did not reveal any data on human toxicity, and it was decided
not to make similar screenings for other siloxanes, but instead make a short
review based on the available original literature.
The main source of information has been the Siloxane Research Program.
The program is run by The Silicones Environmental, Health and Safety
Council of North America (SEHSC) which is a non-profit trade association
comprised of North American silicone chemical producers and importers.
The programme was started in 1993 and includes a series of studies examining
acute and long-term safety of exposure to the fundamental building blocks
of many silicone materials (Meeks 1999). Testing under this programme includes
the following type of tests:
Fundamental research:
• Pharmacokinetics;
• Biochemical toxicology.
Descriptive toxicological studies:
• Subacute studies of up to one month of duration;
• Subchronic studies of up to three months of duration;
• Two-year chronic studies to assess carcinogenicity and chronic effects;
• Developmental studies to assess effects on foetal development;
• Two-generation reproductive and fertility studies;