Registration Dossier

Administrative data

Key value for chemical safety assessment

Effects on fertility

Description of key information

There are no reproductive dose toxicity data on tetradecamethylhexasiloxane (L6), so good quality data for the related substance, decamethyltetrasiloxane (L4, 141-62-8), have been used to assess the reproductive toxicity of tetradecamethylhexasiloxane.

In a combined Repeated Dose Toxicity Study with the Reproduction / Developmental Toxicity Screening Test conducted using a protocol comparable to OECD 422 and to GLP (DCC, 2007) the NOAEC for general and reproductive toxicity was at least 400 ppm (the only concentration tested) according to the study report. However, it should be noted that three female rats in the 400 ppm group with evidence of copulation failed to deliver a litter. One of these three females showed signs of parturition (blood discharge) on gestation day 25, but no pups were found. However, seven implant sites were present. The remaining females produced litters that were similar to the controls.

Effect on fertility: via oral route
Endpoint conclusion:
no study available
Effect on fertility: via inhalation route
Endpoint conclusion:
no adverse effect observed
Dose descriptor:
NOAEC
5 083 mg/m³
Study duration:
subacute
Species:
rat
Effect on fertility: via dermal route
Endpoint conclusion:
no study available
Additional information

There are no reproductive dose toxicity data on tetradecamethylhexasiloxane (L6), so good quality data for the related substance, decamethyltetrasiloxane (L4, 141-62-8), have been used to assess the reproductive toxicity of tetradecamethylhexasiloxane.

Read-across is discussed in detail in Section 7.5. In the key combined repeated dose with reproductive/developmental toxicity screening study conducted according to OECD 422 study and in compliance with to GLP (Dow Corning Corporation, 2007), whole body inhalation exposure of rats to decamethyltetrasiloxane for 28 days did not result in any adverse effects on fertility or reproductive organs attributable to treatment. Therefore the NOAEC for reproductive toxicity was considered to be at least 400 ppm (the highest concentration tested), which is equivalent to approximately 5100 mg/m³. However, it should be noted that three female rats in the 400 ppm group with evidence of copulation failed to deliver a litter. One of these three females showed signs of parturition (blood discharge) on gestation day 25, but no pups were found. However, seven implant sites were present. The remaining females produced litters that were similar to the controls.


Effects on developmental toxicity

Description of key information

There are no developmental toxicity data on tetradecamethylhexasiloxane (L6), so good quality data for the related substance, decamethyltetrasiloxane (L4, 141-62-8), have been used to assess the developmental toxicity of tetradecamethylhexasiloxane. In a combined Repeated Dose Toxicity Study with the Reproduction / Developmental Toxicity Screening Test conducted using a protocol comparable to OECD 422 and to GLP (DCC, 2007) the NOAEC for general and developmental toxicity was at least 400 ppm (the only concentration tested) according to the study report. There were no adverse developmental effects.

Effect on developmental toxicity: via oral route
Endpoint conclusion:
no study available
Effect on developmental toxicity: via inhalation route
Endpoint conclusion:
no adverse effect observed
Dose descriptor:
NOAEC
5 083 mg/m³
Study duration:
subacute
Species:
rat
Effect on developmental toxicity: via dermal route
Endpoint conclusion:
no study available
Additional information

There are no developmental toxicity data on tetradecamethylhexasiloxane, so good quality screening developmental toxicity data for the related substance, decamethyltetrasiloxane (141-62-8), have been used to assess the developmental toxicity of tetradecamethylhexasiloxane.

Read-across is discussed in detail in Section 7.5. In the key combined repeated dose with reproductive/developmental toxicity screening study conducted according to OECD 422 study and in compliance with to GLP (Dow Corning Corporation, 2007), whole body inhalation exposure of rats to decamethyltetrasiloxane for 28 days did not result in any adverse developmental effects attributable to treatment. Therefore the NOAEC for developmental toxicity was considered to be at least 400 ppm (the highest concentration tested), which is equivalent to approximately 5100 mg/m³.

Justification for classification or non-classification

Tetradecamethylhexasiloxane (L6) is not classified for reproductive or developmental toxicity according to Regulation (EC) No 1272/2008.