Solvent naphtha (petroleum), heavy arom.

Endpoint summary

Description of key information

Available data for 6 specific streams within this category and on specific components that are present in some streams (benzene, toluene, styrene, xylenes and ethylbenzene) provide some evidence of skin and eye irritation with controlled exposures to liquid test substances. For all 6 streams and benzene, toluene, styrene, xylenes and ethylbenzene the effects are such that it is considered that all Resin Oils and Cyclic Dienes should be considered to be skin irritants and to be labelled appropriately. One stream (E000044012 [CAS 68478-10-4]) and the components benzene, styrene, xylenes and ethylbenzene produce eye irritation of a severity that warrants labelling for eye irritation results. Based on likely composition of Resin Oils and Cyclic Dienes streams it is proposed that all are labelled as eye irritants. The need for labelling with respect to respiratory irritation is dependent upon available data for the specific stream or the concentration of xylenes in the stream.

Key value for chemical safety assessment

Skin irritation / corrosion

Endpoint conclusion

Endpoint conclusion:

adverse effect observed (irritating)

Eye irritation

Endpoint conclusion

Endpoint conclusion:

adverse effect observed (irritating)

Additional information

Non human data

Skin irritation

Results of animal studies for the streams Cracked distillate [CAS 68477-40-7] (TNO, 1989e), C9 Resinfeed [CAS 68477-54-3] (TNO, 1989f), E000044012 [CAS 68478-10-4] (UBTL, 1990j), E000044146 [CAS 68478-10-4] (UBTL, 1990k), E000144700 [CAS 68516-20-1] (UBTL, 1990l) and C9 Produkt [CAS 94733-07-0] (BASF, 1990b) showed that all were irritating but not corrosive to rabbit skin. Data on the specific components benzene (Jacobs, 1991), toluene (Exxon, 1988), styrene, xylenes (Hine and Zuidema, 1970; Chatterjee et al, 2005; Chevron Chemical Company, 1973) and ethylbenzene (EU RAR, 2008a) indicate irritation following dermal contact with effects sufficiently severe to warrant labelling.

Eye irritation

Data on the streams Cracked distillate [CAS 68477-40-7] (TNO, 1989g), C9 Resinfeed [CAS 68477-54-3] (TNO, 1989h, j), E000044146 [CAS 68478-10-4] (UBTL, 1990m), E000144700 [CAS 68516-20-1] (UBTL 1990n) and C9 Produkt [CAS 94733-07-0] (BASF, 1990c) and on the specific component toluene, indicate that instillation of liquid test substance into the eye may induce some evidence of eye irritation but not of a severity that warrants labelling. For E000044012 [CAS 68478-10-4] (UBTL, 1990m), benzene (Wolf et al, 1956), styrene, xylenes (Hine and Zuidema, 1970; HLA, 1983c, d) and ethylbenzene (EU RAR, 2008a) the effects are sufficient to warrant labelling.

Respiratory irritation

There are no specific data on any of the streams. C8 aromatics (xylenes and ethylbenzene) are considered to be respiratory irritants. Respiratory irritation was seen in mice exposed to high acute concentrations of o- or p-xylene (De Ceaurriz, et al, 1981; HLA, 1983a, b). For ethylbenzene RD50 values of 1432 or 4060 ppm (6215 to 17620 mg/m³) for sensory irritation were determined in different strains of mice (EU RAR, 2008a).

Human information

There is no specific human information concerning skin or eye irritation on any of the streams or on the specific components 1,3-butadiene, naphthalene or isoprene identified as present in some streams. Specific information of value to the risk assessment is available for benzene, toluene and xylenes:

Benzene (Classification: EU -Harmful Xi, R36, R38; GHS/CLP - Category 2 H319, Category 2 H315): Liquid benzene on direct contact with the skin may cause erythema and blistering. Skin contact with benzene removes fat from the tissue which may result in the development of a dry, scaly dermatitis if exposure is repeated or prolonged. High concentrations of benzene vapours are irritating to the mucous membranes of the eyes, nose and respiratory tract (EU, 2008b).

Toluene (Classification: EU -Harmful Xi, R38; GHS/CLP - Category 2 H315): No data on skin irritation have been found. The EU RAR (EU, 2003a) stated “it is well known that toluene has a degreasing effect on the skin. After repeated exposures, toxic contact dermatitis may develop. ” There are no data from direct exposure of human eyes to liquid toluene. A number of human experimental studies in volunteers have investigated reports of eye “irritation” resulting from exposures to toluene in ambient air. These studies indicate that toluene produces subjective sensations of eye irritation at concentrations ≥ 75 ppm (EU, 2003a). In a recent study, Muttray et al (2005) exposed twenty healthy men to a constant level of 50 ppm toluene. Acute symptoms related to eye irritation were assessed with the Swedish Performance Evaluation System (SPES) self-assessment questionnaire, once before and 3 times during exposure. Values obtained during exposure were related to pre-exposure values. There was no effect of toluene exposure on "irritation to the eye", "watering eyes" or "blurred vision”. 50 ppm (188 mg/m³) toluene is a NOAEC for eye irritation in humans.

Xylenes (Classification: EU -Harmful Xi, R36, R37, R38; GHS/CLP - Category 2 H319, Category 3 H335, Category 2 H315): There is little human information available but the ATSDR (2007c) reports that dermal exposure of humans to xylene causes skin irritation, dryness and scaling of the skin, and vasodilation. Mild irritation of the eye and upper respiratory tract was reported in volunteer studies where individuals were exposed to 442 mg xylene/m³ (SCOEL, 1992) for 15-30 minutes (Carpenter et al, 1975; Hastings et al, 1984). No symptoms of nose or throat irritation have been reported in volunteers exposed to mixed xylenes up to 400 ppm (UK HSC, 2001).

References

ATSDR (2007c). Toxicological profile for xylene. US Dept Health and Human Services.

EU (2003a). European Union Risk Assessment Report for Toluene. EC Joint Research Centre http: //ecb. jrc. ec. europa. eu/DOCUMENTS/Existing- Chemicals/RISK_ASSESSMENT/REPORT/toluenereport032. pdf

EU (2008a). European Union Risk Assessment Report for Ethylbenzene. EC Joint Research Centre http://ecb.jrc.ec.europa.eu/DOCUMENTS/Existing-Chemicals/RISK_ASSESSMENT/REPORT/ethylbenzenereport057.pdf

EU (2008b). European Union Risk Assessment Report for Benzene. EC Joint Research Centre. http: //ecb. jrc. ec. europa. eu/documents/Existing-chemicals/RISK_ASSESSMENT/REPORT/benzenereport063. pdf.

SCOEL (1992). Recommendation from the scientific expert group on occupational exposure limits for xylenes.

UK HSC (2001). UK HSC Consultation Document on EC Directive 2000/39/EC establishing a first list of indicative occupational exposure limit values at EC level in implementation of council directive 98/24/EC on the protection of the health and safety of workers from the risks related to chemical agents at work. UK Health and Safety Commission. Available from www.hse.gov.uk/condocs.

Effects on skin irritation/corrosion: irritating

Effects on eye irritation: irritating

Justification for classification or non-classification

There are sufficient data on the streams Cracked distillate [CAS 68477-40-7], C9 Resinfeed [CAS 68477-54-3], E000044012 [CAS 68478-10-4], E000044146 [CAS 68478-10-4], E000144700 [CAS 68516-20-1] and C9 Produkt [CAS 94733-07-0] and on the component substances benzene, toluene, styrene, xylenes and ethylbenzene indicate that they are irritating to skin. It is proposed that Resin Oils and Cyclic Dienes streams are considered to be skin irritants and labelled “Irritating to skin” Xi R38 according to Dir 1999/45/EC or “Causes skin irritation” Category 2 H315 according to Reg (EC) 1272/2008.

Although of the tested streams only E000044012 [CAS 68478-10-4] produced irritation of a severity to warrant labelling as irritating to rabbit eye, the component substances benzene, styrene and xylenes are classified as eye irritants. It is assumed that the combined concentration of eye irritating substances will normally exceed the cut-off for classification under DPD (≥20%) and CLP (≥10%) and, therefore it is proposed that Resin Oils and Cyclic Dienes streams are considered to be eye irritants and labelled as “Irritating to eyes” Xi R36 according to Dir 1999/45/EC or “Causes serious eye irritation” Category 2 H319 under Reg (EC) 1272/2008.

Xylenes are considered to be respiratory irritants. If the concentration of xylenes is ≥10% the stream will be required to be classified “Irritating to respiratory system‟or “May cause respiratory irritation” Category 3 H335 under Reg (EC) 1272/2008.