2-(propyloxy)ethanol

Endpoint summary

Description of key information

In laboratory animals, the acute oral LD50 for the test substance in a key study was 3089 mg/kg bw.  The acute dermal LD50 value from a key study was 1337 mg/kg bw.  Acute inhalation LC50 values are in excess of 9061 mg/m3.

Key value for chemical safety assessment

Acute toxicity: via oral route

Endpoint conclusion

Endpoint conclusion:

no adverse effect observed

Dose descriptor:

LD50

Value:

3 089 mg/kg bw

Acute toxicity: via inhalation route

Endpoint conclusion

Endpoint conclusion:

no adverse effect observed

Dose descriptor:

discriminating conc.

Value:

9 061 mg/m³ air

Acute toxicity: via dermal route

Endpoint conclusion

Endpoint conclusion:

no adverse effect observed

Dose descriptor:

LD50

Value:

1 337 mg/kg bw

Additional information

Oral Toxicity

In a key stud in rats, the acute oral LD50 of the test substance was found to be 3089 mg/kg bw (29.70 mM/kg bw) in fasted animals and 6178 mg/kg bw (59.40 mM/kg bw) in fed animals. In other studies in laboratory animals, the acute oral toxicity of the test substance was found to be low to moderate, with LD50 values ranging from > 500 mg/kg bw to 5000 mg/kg bw. In oral gavage studies in rats, significant mortality only occurred at dose levels in excess of 1000 mg/kg bw. Clinical signs of toxicity noted included narcosis and red discolored urine. Narcosis was most pronounced after 1 to 4 hours following dosing, with sluggishness and lowered body temperatures observed after 24 hours. Pathology noted included extensive kidney and liver damage with congested livers and pale kidneys reported. In rats and mice dosed at 200 to 3200 mg/kg bw, similar effects were noted including red discolored urine at all dose levels. In guinea pigs, significant mortality occurred at 2000 mg/kg bw and higher doses. Clinical signs in guinea pigs included narcosis and lowered body temperatures. Pathology reported in guinea pigs included congested livers and pale kidneys and pronounced hemorrhagic damage to the stomach, reported as more pronounced than that in rats. The LD50 for guinea pigs was reported as 2200 mg/kg bw.

Inhalation Toxicity

In a key study, male rats were exposed to 273 to 2132 ppm of the test substance for approximately 6 to 7 hours.  Hemolysis was no longer observed after 24 hours and hemoglobin concentration and hematocrit were normal by 2 weeks. The LC50 in this latter study was reported as > 2132 ppm (9061 mg/m3). In a second supporting study, male rats were exposed to a saturated vapor from 4 to 7 hours. No mortality was noted but body weights were decreased in exposed rats and all displayed bloody urine when removed from exposure chambers. At sacrifice, animals exposed for 4 hours were essentially normal, wheras animals exposed 7 hours showed extensive kidney, liver and lung damage. The 4 -hour LC50 was reported as > 9800 mg/m3.

Dermal Toxicity

In a key study, rabbits were administered 541, 1092, 2184 or 4368 mg/kg bw under occlusive wrap for 24 hours and observed subsequently 14 days. Significant mortality was present at the highest dose level. Some or all animals dosed at 1092 mg/kg bw or above had discolored livers, enlarged and dark red kidneys, dark red stomachs and red discolored large and small intestines. Slight skin irritation was present in surviving animals at the 2184 mg/kg bw dose level. The dermal LD50 calculated from this study was 1337 mg/kg bw. In a supporting study, rabbits were exposed for 24 hours by cuff to 0.2, 0.5 or 1.0 g/kg bw of the test substance dissolved in Dowanol DPM as vehicle. There was no mortality and the treatment sites were essentially normal. The LD50 was reported as > 1 g/kg bw. Male and female guinea pigs were administered cotton poultices at doses of 3.16, 5.0 or 7.95 g/kg bw under semiocclusive wrap for 4 days. At the highest exposure concentration, 5 of 6 exposed animals died. Examination of internal organs revealed congested livers and pale kidneys. Bile was a deep yellow to orange and urine appeared blue to black. Gross pathology was said to parallel that seen in rats except that damage to the stomach was more pronounced. The LD50 was reported as 5.6 g/kg bw in this latter study. In another study in guinea pigs, doses of from 1 to 5 mL/kg bw were applied under occluded patch for 24 hours. Mortality of all animals was reported at a dose level of 5 mL/kg bw and above. The LD50 was reported as > 1 mL/kg bw (913 mg/kg bw).

Justification for classification or non-classification

Acute oral toxicity

Based on the acute oral toxicity of the subject chemical, it would not be rated for acute oral toxicity under either the EU DSD classification criteria (EU Directive 67/548/EEC) or under the EU CLP classification criteria (EU Regulation 1272/2008). Under the United Nations Globally Harmonized System of Classification and Labelling of Chemicals (UN-GHS), the test material would be rated as Acute Toxicity, Category 5.

Inhalation toxicity

Based on the acute inhalation toxicity of the subject chemical, it would not be rated for acute inhalation toxicity under either the EU DSD classification criteria (EU Directive 67/548/EEC) or under the EU CLP classification criteria (EU Regulation 1272/2008) or the United Nations Globally Harmonized System of Classification and Labelling of Chemicals (UN-GHS).

Dermal toxicity

Based on the acute dermal toxicity of the subject chemical, it would be rated R21 (harmful if swallowed) under the EU DSD classification criteria (EU Directive 67/548/EEC). Under the EU CLP classification criteria (EU Regulation 1272/2008) it would be rated as Acute Toxicity, Category 4. It would receive a similar rating under the United Nations Globally Harmonized System of Classification and Labelling of Chemicals (UN-GHS).