Ethylene oxide

Toxicological Summary

Workers - Hazard via inhalation route

Systemic effects

Long term exposure

Hazard assessment conclusion:

DMEL (Derived Minimum Effect Level)

Value:

1.8 mg/m³

Most sensitive endpoint:

carcinogenicity

Route of original study:

By inhalation

DNEL related information

DNEL derivation method:

other: SCOEL value is used

Acute/short term exposure

Hazard assessment conclusion:

DNEL (Derived No Effect Level)

Value:

10 mg/m³

Most sensitive endpoint:

neurotoxicity

Route of original study:

By inhalation

DNEL related information

DNEL derivation method:

ECHA REACH Guidance

Overall assessment factor (AF):

10

Dose descriptor starting point:

NOAEC

Value:

100 mg/m³

Explanation for the modification of the dose descriptor starting point:

The point of departure for the acute DNEL is taken from the NOAEC of a subchronic toxicity study in monkeys which was 50 ppm (100 mg/m3; Setzer er al., Toxicol. Ind. Health 12, 667 -682; 1996). The neurotoxicity observed in this study could result from acute subclinical effects, therefore the NOEL is used in a conservative approach to derive an acute DNEL for neurotoxicity.

AF for dose response relationship:

1

AF for interspecies differences (allometric scaling):

2

AF for other interspecies differences:

1

AF for intraspecies differences:

5

AF for the quality of the whole database:

1

AF for remaining uncertainties:

1

Local effects

Long term exposure

Hazard assessment conclusion:

DMEL (Derived Minimum Effect Level)

Value:

1.8 mg/m³

Most sensitive endpoint:

carcinogenicity

DNEL related information

DNEL derivation method:

other: The SCOEL is used.

Acute/short term exposure

Hazard assessment conclusion:

high hazard (no threshold derived)

DNEL related information

Workers - Hazard via dermal route

Systemic effects

Long term exposure

Hazard assessment conclusion:

high hazard (no threshold derived)

Acute/short term exposure

Hazard assessment conclusion:

high hazard (no threshold derived)

DNEL related information

Local effects

Long term exposure

Hazard assessment conclusion:

high hazard (no threshold derived)

Acute/short term exposure

Hazard assessment conclusion:

high hazard (no threshold derived)

Workers - Hazard for the eyes

Local effects

Hazard assessment conclusion:

medium hazard (no threshold derived)

Additional information - workers

Carcinogenicity in animal experiments is considered to be the critical endpoint for a chronic inhalation DNEL / DMEL. The Directive (EU) 2017/2398 of the European Parliament and of the Council of 12 December 2017 amending Directive 2004/37/EC on the protection of workers from the risks related to exposure to carcinogens or mutagend at work contains the following article: Ethylene oxide meets the criteria for classification as carcinogenic (category 1B) in accordance with Regulation (EC) No 1272/2008 and is therefore a carcinogen within the meaning of Directive 2004/37/EC. It is possible, on the basis of the available information, including scientific and technical data, to set a limit value for that carcinogen. SCOEL has identified, for ethylene oxide, the possibility of significant uptake through the skin. It is therefore appropriate to establish a limit value for ethylene oxide and to assign to it a notation indicating the possibility of significant uptake through the skin.

The limit value for occupational exposure (OEL) for ethylene oxide is 1.8 mg/m³ (= 1 ppm).

    

  

General Population - Hazard via inhalation route

Systemic effects

Long term exposure

Hazard assessment conclusion:

hazard unknown but no further hazard information necessary as no exposure expected

Acute/short term exposure

Hazard assessment conclusion:

hazard unknown but no further hazard information necessary as no exposure expected

DNEL related information

Local effects

Long term exposure

Hazard assessment conclusion:

hazard unknown but no further hazard information necessary as no exposure expected

Acute/short term exposure

Hazard assessment conclusion:

hazard unknown but no further hazard information necessary as no exposure expected

DNEL related information

General Population - Hazard via dermal route

Systemic effects

Long term exposure

Hazard assessment conclusion:

hazard unknown but no further hazard information necessary as no exposure expected

Acute/short term exposure

Hazard assessment conclusion:

hazard unknown but no further hazard information necessary as no exposure expected

DNEL related information

Local effects

Long term exposure

Hazard assessment conclusion:

hazard unknown but no further hazard information necessary as no exposure expected

Acute/short term exposure

Hazard assessment conclusion:

hazard unknown but no further hazard information necessary as no exposure expected

General Population - Hazard via oral route

Systemic effects

Long term exposure

Hazard assessment conclusion:

hazard unknown but no further hazard information necessary as no exposure expected

Acute/short term exposure

Hazard assessment conclusion:

hazard unknown but no further hazard information necessary as no exposure expected

DNEL related information

General Population - Hazard for the eyes

Local effects

Hazard assessment conclusion:

hazard unknown but no further hazard information necessary as no exposure expected

Additional information - General Population

No DNELs were recommended for the general population. As far as it is forseen, EO as a reactive compound is produced as a building block for chemical synthesis and used only within closed systems. Work place exposure is already strictly controlled and, according to present measurements, EO concentrations outside of the plants are not measurable. No foreseeable exposure of the general population is known under the scope of REACH.

No exposure via industrial processes should occur unless in the case of accidental release. For this scenario, however, meaningful values have already been designed elsewhere (AEGLs).

It should be noted that the hazard assessment conclusion is not suggested to be appropriate, because the hazard for the general population if exposed to EO is the same as pointed out for workers. However, there is minor or no risk for the general population being exposed to EO and thus, the more acurate conclusion in this case would be "no risk identified".