Reaction mass of (2-methoxymethylethoxy)propanol and [2-(2-methoxymethylethoxy)methylethoxy]propanol and sodium methanolate

Endpoint summary

Description of key information

The acute oral toxicity of DPM was determined to be 5.66 mL/kg in groups of 5 rats dosed by oral gavage and followed for 14 days.  In rabbits, dermal LD50 was determined to be 9150 mg DPM/kg.  An inhalation study in rats found no mortalities after 8 hours exposure to a maximally saturated atmosphere of DPM.  Sodium methanolate had oral and dermal LD50 values in rats of 2037 mg/kg bw and 2000 mg/kg bw, respectively.  An atmosphere enriched in the methanolate was not acutely toxic.

Key value for chemical safety assessment

Acute toxicity: via oral route

Endpoint conclusion

Dose descriptor:

LD50

Value:

2 037 mg/kg bw

Acute toxicity: via inhalation route

Endpoint conclusion

Dose descriptor:

discriminating conc.

Acute toxicity: via dermal route

Endpoint conclusion

Dose descriptor:

LD50

Value:

2 000 mg/kg bw

Additional information

There is no acute toxicity information for the glycol ethers heavies. In accordance with Section 2 of REACH Annex XI, acute oral and dermal toxicity testing of the glycol ethers heavies is not scientifically justified based on the reactive nature of the test substance and the potential for skin corrosivity. In addition, in accordance with column 2 of REACH Annex VIII, acute inhalation toxicity testing is also waived based on the low vapor pressure of the test substance, which precludes significant exposure by this route. No significant exposure to aerosols, particles or droplets of the test substance is anticipated.

Supporting acute toxicity data for propylene glycol ether components:

The propylene glycol ether components of the glycol ethers heavies mixture are of known low acute toxicity by the oral, dermal or inhalation routes of exposure (see OECD, 2003). As representative of the class, DPM is of low acute oral toxicity in the rat (LD50 = 5.66 mL/kg bw) and of low acute dermal toxicity in the rabbit (LD50 = 9150 mg/kg bw).

Supporting acute toxicity data for sodium methanolate:

Sodium methanolate is of low acute toxicity by the oral and dermal routes in the rat, with LD50 values of 2037 mg/kg bw and > 2000 mg/kg bw, respectively. An atmosphere enriched in the methanolate (concentration unspecified) was not acutely toxic (OECD, 2006).

Justification for classification or non-classification

While the DPM and TPM components of this mixture are without toxicity classifications, the presence of the sodium methanolate catalyst results in the proposed classification of Xn, R68/21/R22/R23 (EU Directive 67/548/EEC). This is based on the presence of methanol, at a level less than 10% by weight based on the methanolate maximum concentration. Under the EU CLP classification criteria (EU Regulation 1272/2008), the glycol ethers heavies would be classified as Acute Toxicity Category 3 and STOT SE 2, based on the presence of methanol, at a level less than 10% by weight based on the methanolate maximum concentration. As rodent studies on this material would not be expected to provide a meaningful characterisation of human health hazard due to the unique sensitivity of humans and non-human primates to methanol toxicity, it is proposed to base the classification and labeling, as well as risk assessment values for this material, on the sodium methanolate content.