3-aminopropyltriethoxysilane

Endpoint summary

Key value for chemical safety assessment

Effects on fertility

Effect on fertility: via oral route

Dose descriptor:

NOAEL

600 mg/kg bw/day

Additional information

No other studies were available for this endpoint. This study (reliability 1) has some shortcomings compared to a standard reproductive study.

However, no further animal study should be conducted. A reliable four-week aerosol inhalation short-term toxicity study is available (BRRC 1991) and shows no adverse toxic effects. A 90-day repeated dose oral study (OECD 408) examining toxicity to reproduction is included in this dataset. This study was considered suitable for selection as the key study for this endpoint, although it would not meet all the requirements of a one generation reproduction toxicity study (OECD 415). The study does not show toxicity results of particular concern. We consider the study results being representative also for inhalative exposure hazards. Therefore, the 90 day oral reprotoxic study is considered adequate to cover testing requirements as laid out in Annex IX.

There is no evidence that the substance may have dangerous properties that cannot be detected in a 90-day oral study. There are no reprotoxic effects known from substances with a clear relationship in molecular structure with the substance being studied.

There is no particular concern with regard to exposure (e. g. use in consumer products leading to exposure levels which are close to the dose levels at which toxicity is observed). The frequency and duration of human exposure does not indicate that a long-term study is needed. Exposure to consumers is not considered a significant route of exposure; most of the RCRs for consumer exposure are very low for both long-term inhalation and long-term dermal exposure.

Available reprotoxic data is considered adequate for the hazard assessment of this substance. As was demonstrated by RIVM, two generation reprotoxic studies yielded similar overall NOAELs compared to subchronic toxicity tests (Aldert Piersma, RIVM Health Protection Research Laboratory, SETAC Brussels 24. October 08). A pragmatic approach calls for a reduced animal testing and therefore for excluding second generation endpoints which are highly unlikely to contibute to RA or C&L. Overall we strongly believe that this is the case for the substance 3-aminopropyltrimethoxysilane.

Therefore the information is considered sufficient for requirements as laid out in Annex X.

Short description of key information:
Only one study examining toxicity to reproduction was included in this dataset. This study was a 90-day repeated dose oral study (OECD 408) in which the test material was given by gavage in peanut oil to male and female rats, with examinations that included the reproductive organs, sperm parameters and oestrus cycle. This study was considered suitable for selection as the key study for this endpoint, although it would not meet all the requirements of, say, a one generation reproduction toxicity study (OECD 415). The study identified an NOAEL for reproductive effects of 600 mg/kg bw/day (the highest dose tested).

Effects on developmental toxicity

Description of key information

The key developmental toxicity study was an oral (gavage) study in male and female rats conducted in a manner similar to OECD 414. The study identified maternal and teratogenicity NOAELs of 100 mg/kg bw/day, with the corresponding LOAELs at 600 mg/kg bw/day. Effects at 600 mg/kg bw/day included increased mortality, clinical observations and reduced body weight gain in dams, and increased foetal skeletal variation.

Effect on developmental toxicity: via oral route

Dose descriptor:

NOAEL

100 mg/kg bw/day

Additional information

The key study was chosen from four oral rat studies of reliability 1 or 2 in which the test substance was given by gavage in peanut oil (3 studies) or neat. The results of these studies were not greatly dissimilar and the key study was the most recent of the two with reliability 1. None of the three supporting studies provided evidence that would challenge the absence of classification determined from the key study.

Justification for classification or non-classification

The available data do not support classification for reproductive or developmental toxicity.