Gases (petroleum), C3-5 olefinic-paraffinic alkylation feed

Endpoint summary

Description of key information

Members of Other Petroleum Gases category are flammable gases at room temperature.  Therefore, in accordance with section 2 of REACH Annex XI, neither skin nor eye irritation studies need be conducted. There are no indications that main constituents of the Petroleum Gases are skin or eye irritants, but direct skin or mucous membrane contact with liquid forms of C1- C4 alkane gases may cause burns and frostbite due to the extreme cold of the liquid. Mild rhinitis has only been reported following lifetime exposure to high concentrations of propene gas. Streams containing benzene will not trigger classification for irritation since this is present at less than 0.3% w/w in the category.

Key value for chemical safety assessment

Skin irritation / corrosion

Endpoint conclusion

Endpoint conclusion:

no adverse effect observed (not irritating)

Eye irritation

Endpoint conclusion

Endpoint conclusion:

no adverse effect observed (not irritating)

Respiratory irritation

Endpoint conclusion

Endpoint conclusion:

no adverse effect observed (not irritating)

Additional information

In accordance with Section 2 of REACH Annex XI, studies on skin and eye irritation do not need to be conducted as members of the Petroleum Gases category are flammable gases at room temperature.

Category members are not expected to be irritating and this is confirmed by pre-guideline rabbit skin and eye irritation studies on formulations although these data cannot be relied upon since there are insufficient details on how the test materials (as gases) were applied (Anon, 1982. Final report of the safety assessment of isobutane, isopentane, n-butane and propane, J American College of Toxicology, Volume 1, Number 4, 127-142).

 

Skin

Non-human information

No guideline studies available.

 

Human information

Very slight and transient erythema occurred randomly among the subjects following repeated applications of aerosol products, containing a mixture of isobutane and propane at 64.5% and 70% by weight, respectively. The reactions were reported to be negligible. Both isobutane and propane were considered practically non irritant to human skin (Anon 1982).

Direct skin contact with liquid forms of C1- C4 alkane gases may cause burns and frostbite due to the extreme cold of the liquid (rapid evaporation lowers the skin temperature causing frost injuries) (Cavender 1994).

Although propene has been used in humans at concentrations sufficient to induce anaesthesia, there is only one literature report of potential adverse irritation effects associated with repeated induction of anaesthesia in one volunteer “after the first few breaths, there was usually slight reddening of the eyelids with some lacrimation and flushing of the eyes. Sometimes coughing would occur from pharyngeal irritation.” In this study, to efficiently induce anaesthesia, very high concentrations (688,000 – 861,000 mg/m3) of propene were rapidly introduced ( Kahn and Riggs LK, 1931). This information is not considered useful in assessment of the irritation potential of propene gas, with its lower explosive limit of (34,000 mg/m3).

 

Eye

Non-human information

No guideline studies available.

 

Human information

Direct mucous membrane contact with liquid forms of C1- C4 alkane gases may cause burns and frostbite due to the extreme cold of the liquid (Cavender 1994).

 

Respiratory tract

Non-human information

No data exist for the C1-C4 alkanes. There are no indications of irritation from repeat dose inhalation studies.

 

Mild rhinitis (mild nasal inflammation) was reported in rats following lifetime exposure to high concentrations of propene gas, a main constituent in the category (NTP,1985) & (Harkema 2002). However, any irritant properties in rodents were mild in nature, lacking a clear dose-response relationship and reported only when high concentrations of propene gas were maintained throughout lifetime exposure.

 

 

Human information

Berzins et al (1995) reported human exposure to propane at 100000 ppm (180 mg/L) caused slight dizziness but no mucosal irritation of nose, eyes or respiratory tract was observed.

Although propene has been used in humans at concentrations sufficient to induce anaesthesia, there is only one literature report (Kahn and Riggs, 1931) of potential adverse irritation effects associated with repeated induction of anaesthesia in one volunteer. Since very high concentrations of propene were used (688,000 – 861,000 mg/m3), this information is not considered useful in assessment of the irritation potential of propene gas, with its lower explosive limit of 34,000 m/m3.

Justification for classification or non-classification

There is no evidence that members of this category are irritating to skin or eyes. 

Any propene-induced rhinitis has been reported as mild in nature, occurring in rodents only after lifetime exposure to high concentrations (5,000ppm & 10,000ppm (8,600 and 17,200 mg/m3) of propene gas.

These findings do not warrant classification for skin, eye, or respiratory tract irritancy under DPD (Dir 1999/45/EC) or GHS/CLP. Streams containing benzene will not trigger classification for irritation since this is present at less than 0.3% w/w in the category (EU:R36/R38; GHS/CLP: Cat 2 H319/Cat 2 H315 would be triggered at levels of > 20 % or 10% respectively).