Extracts (petroleum), deasphalted vacuum residue solvent

Endpoint summary

Description of key information

Key read across acute oral (similar to OECD 401), dermal (similar to OECD 402), and inhalation (OECD 403)  toxicity studies were identified and used to predict the acute toxicity values for RAE.

• The oral LD50 was > 5000 mg/kg bw in male and female rats.

• The dermal LD50 was > 3000 mg/kg/bw in male and female rabbits.

• The inhalation (aerosol) LC50 was > 5 mg/L (or > 5000 mg/m3) in male and female rats.

Key value for chemical safety assessment

Acute toxicity: via oral route

Endpoint conclusion

Dose descriptor:

LD50

Value:

5 000 mg/kg bw

Acute toxicity: via inhalation route

Endpoint conclusion

Dose descriptor:

LC50

Value:

5 000 mg/m³ air

Acute toxicity: via dermal route

Endpoint conclusion

Dose descriptor:

LD50

Value:

3 000 mg/kg bw

Additional information

For purposes of classification and labelling and registration under REACH, aromatic extracts are sub-divided into the categories of distillate aromatic extracts (DAE), treated distillate aromatic extracts (TDAE), and residual aromatic extracts (RAE). Distillate aromatic extracts are derived from the extraction conducted on distillate base oils, whereas residual aromatic extracts are the result of extraction on residual oil that has undergone de-asphaltation. The starting materials from which DAE and TDAEs are derived boil across the distillation range of 3-7 ring PACs, the constituents of concern that may cause toxicity. In addition, they have a much lower viscosity compared to the residual aromatic extracts. Therefore reading across to data on DAEs for RAEs is likely to be conservative. 

 

Key oral, dermal, and inhalation toxicity studies were identified for distillate aromatic extracts. In a key read-across acute oral toxicity study, groups of fasted, 7 week old Sprague-Dawley rats (5/sex) were given a single oral dose of undiluted light paraffinic distillate solvent at a dose of 5000 mg/kg body weight (API, 1986). Animals were observed for 14 days. Clinical signs observed included: hypoactivity, ataxia, red stained face, yellow-stained anal area, diarrhoea, and oily haircoat. All animals had returned to normal within 8 days of test material administration. The oral LD50 was determined to be greater than 5000 mg/kg body weight in males and females.  In a key read-across acute dermal toxicity study, groups of New Zealand White rabbits (4/sex) were dermally exposed to undiluted light paraffinic distillate solvent extract for 24 hours to 10% of total body area at doses of 2000 and 3000 mg/kg bw (API, 1986). Animals then were observed for 14 days. At the 2000mg/kg bw dosage level: diarrhoea, dyspnoea, hypoactivity, prostration, emaciation, soft stool. At the 3000mg/kg bw dosage level: no signs of systemic toxicity (or mortality). Dermal irritation was observed and ranged from slight to severe for erythema and oedema. The dermal LD50 was determined to be greater than 3000 mg/kg body weight in both males and females.  In a key read-across acute inhalation toxicity study, groups of young adult Sprague Dawley rats (5/sex) were exposed by inhalation route to distillate aromatic extract for 4 hours to whole body at a concentrations of 5.0 mg/L (ARCO, 1983). Animals then were observed for 14 days. All animals were lethargic during the last 2 hours of exposure. From hour 2 of treatment until the first hour post-exposure, animals kept their eyes partially closed and were lacrimating. One rat displayed red nasal discharge following exposure and red ocular discharge. Another rat exhibited yellow eye discharge during the fourth hour post-exposure and red eye discharge the morning following discharge until the end of the third day post-treatment. These findings are considered related to treatment. Three rats of each sex showed pallor and/or swelling of the kidneys. These findings may be related to treatment. The acute aerosol LC50 of distillate aromatic extract is greater than 5.0 mg/L (5,000 mg/m3) of air.

Justification for classification or non-classification

Based on evaluation of all the acute toxicity data on DAE discussed above, it can be inferred that RAE does not meet the criteria for classification as an acute oral, inhalation, or dermal toxicant under the CLP Regulation, (EC)1272/2008, because the LD50/LC50 values are greater than the limits for classification defined in the regulations.