Nonanol, branched and linear

Endpoint summary

Key value for chemical safety assessment

Effects on fertility

Additional information

Reproduction: The conclusion that the members of the aliphatic alcohol  category (C6 to C22) are not expected to impair fertility is based on a  weight of evidence approach using data from reproductive  screening studies [C12 (dodecanol), C18 (octadecanol)],a fertility  study [C22 (docosanol)], together with a lack of effect on the 

reproductive organs in repeat dose studies over the range of linear and  essentially linear alcohols. Based on this it is concluded that nonanol, branched and linear is not expected to impair fertility.

Chronic and sub-chronic toxicity studies have shown that long chain alcohols (LCA) are of low toxicity. Furthermore, combined repeated-dose studies with developmental endpoints, as well as reproductive and developmental studies showed no effects at the highest dose tested.

Rather than having separate values for the three endpoints, one endpoint “systemic effects” has been used instead. Since the NOAELs do not vary greatly across the category, one key study has been chosen as being representative of the whole category.

 

C6, Hexanol has been chosen as the category representative because shorter chain molecules are usually regarded as more toxic when compared to structural analogues with longer carbon chain lengths.

Short description of key information:
Two read across feeding studies reported a lack of effects on the reproductive organs of rats receiving 1 -hexanol (NOAEL 1127 mg/kg) (Scientific Associates Inc., 1966, rel; 2) and 1 -dodecanol (NOAEL 2000 mg/kg) (Hansen 1992, rel; 2 ). A read across from octan-1-ol is designated the key study for developmental toxicity reporting a NOAEL of 1300 mg/kg bw/day (Hellwig, 1997; rel 2).

Effects on developmental toxicity

Description of key information

A reliable developmental toxicity key study in rats by whole body inhalation exposure to 1 –nonanol over 19 days, reported a developmental and maternal NOAEC > 0.15mg/l, which was the highest dose tested. (Nelson et al, 1990). 
 
In a reliable inhalation study (Nelson et al, 1990), the NOAEC for maternal toxicity, foetotoxicity and teratogenicity in rats following inhalation exposure to 1-nonanol during gestation days 1-19 was > 0.15 mg/l (the highest attainable concentration).

Additional information

Developmental effects: Based on the read across from octan-1 -ol and weight of evidence from other alcohols across the category, it is concluded that nonanol, branched and linear is unlikely to be a developmental toxicant in the absence of maternal toxicity.

Justification for classification or non-classification

Based upon the above information, nonanol branched and linear is not required to be classified in accordance with EU guidelines.