Registration Dossier

Administrative data

Description of key information

Oral LD50 (rat) > 5840 mg/kg bw
Dermal LD 50 (rat) > 2920 mg/kg bw
Inhalative LD50 (rat) > 23300 mg/m³

Key value for chemical safety assessment

Additional information

Before the current ECHA nomenclature rules became effective, we adopted the IUPAC name Hydrocarbons, C7-9, n-alkanes, isoalkanes, cyclics (EC number 920-750-0) as the identifier for the substance and this was the name that was used during the pre-registration phase of REACH. Also during this time, samples of the product were collected and the required physicochemical studies were conducted. The resulting robust studies summaries were entered into the IUCLID dossier using this name and EC number.

Between 2008 and 2009 ECHA issued a specific document about the nomenclature to be used under REACH, the so called REACH Implementation Project 3.10. The implications of this document to the appropriate nomenclature for the registered substance were only fully understood by us beginning in late 2009/early 2010.

As such, during the creation of the robust study summaries in IUCLID, the discrepancy with the substance naming was not noticed. As a result, it appears in IUCLID that the tested substance indicated is not the same as the registered one; however, if robust study summaries and/or associated study reports use the substance name “Hydrocarbons, C7-C9, n-alkanes, isoalkanes, cyclics,” they are actually referring to the registered substance “Hydrocarbons, C7-C8, n-alkanes” according to the revised REACH nomenclature rules.

Oral

 

The acute oral toxicity of hydrocarbons, C7-C9, n-alkanes, isoalkanes, cyclics was tested following a standard method. Two male and two female rats were exposed to 1, 2, 4, or 8 mL/kg of undiluted test substance orally by gavage. The animals were then observed for the next 9 days for mortality. No animals of either sex died during the study. The LD50was > 8 mL/kg for both male and female rats. Based on the density given in the study report, the LD50was calculated to be higher than approx. 5840 mg/kg bw (Shell Chemicals, 1977).

 

Inhalation

 

Wistar rats (5/sex) were exposed via inhalation (whole body) to hydrocarbons, C7-C9, n-alkanes, isoalkanes, cyclics at 23300 mg/m³ for 4 h (similar to OECD 403). Clinical signs during exposure included signs of slight irritation, partial closing of the eyes, lacrimation, a reduced respiration rate and restless behavior. One male rat died during the exposure. The signs recorded during the observation period were hyperactivity and abnormal breathing. Reduced body weight for 1-2 days and reduced food consumption for 1 day following exposure. The lung weight for the decedent rat was high, but within normal limits for the others. The LC50was greater than 23300 mg/m³ (Shell Chemicals, 1988).

In another study, male and female Charles River CD rats (2/sex/concentration) were exposed via whole body inhalation to hydrocarbons, C7-C9, n-alkanes, isoalkanes, cyclics at 11000, 29000, 33000, 42000, or 49000 mg/m³ for four hours (similar to OECD 403). Clinical signs included mild piloerection, restlessness and tremors of the fore-paws. None of 4 rats died at 33000 mg/m³, 3 of 4 rats died at 42000 mg/m³ and 7/8 rats died at 49000 mg/m³. Before death the rats lapsed into a comatose state, and one animal showed excess salivation and had a blood-stained nasal discharge. Surviving animals exhibited mild excitability on removal from the chamber and slight ataxia was observed, however, this effect disappeared within 1 h after the end of exposure. The animals surviving the exposure also survived the subsequent 14 day observation period. The LC50was 33000 - 42000 mg/m³ (Shell Chemicals, 1977).

Male Wistar rats (10/concentration) were exposed in a further study via whole body inhalation to Ligroine (VM&P Naphatha) at 4400, 9800 or 26000 mg/m³ for four hours (similar to OECD 403). Mortality was 100% at 26000 mg/m³; no deaths at 9800 or 4400 mg/m³. Clinical signs in rats at higher concentrations included eye irritation and central nervous system depression (poor coordination with convulsions preceding death). Rats exposed to 4400 mg/m³ did not exhibit physical signs during or after exposure or during 14 days of observation. Gross necropsy observations of rats that died after 26000 mg/m³ Ligroine (VM& P Naphtha) were congestion of lung and liver. Bile duct proliferation and increased number of leukocytes in sinusoids of the spleen were noted in 3 of 6 livers examined histologically Rats killed 14 days after inhaling 9800 or 4400 mg/m³ for 4 hrs evidenced singly occurring bronchitic effects and extraneous lesions in organs other than the lung. The LC50was 16000 mg/m³ (Carpenteret al., 1975).

 

Dermal

 

The substance hydrocarbons, C7-C9, n-alkanes, isoalkanes, cyclics was applied on the shaved backs of Charles River CD rats (2/sex/dose) at 1, 2, and 4 mL/kg bw (730, 1460, and 2920 mg/kg bw) for 24 hours in accordance with the method of Noakes and Sanderson, 1969 [Br. J Indust. Med 26:59-64] (similar to OECD 402). No deaths or clinical signs were observed. The LD50was greater than 4 mL/kg bw, corresponding to 2920 mg/kg bw (Shell Chemicals, 1977).

Justification for classification or non-classification

The available data on the acute toxicity of hydrocarbons, C7-C9, n-alkanes, isoalkanes, cyclics are conclusive but not sufficient for classification. However, acute exposure may result in non-lethal narcotic effects and the substance hydrocarbons, C7-C9, n-alkanes, isoalkanes, cyclics poses aspiration hazard.

DSD: R65-67

CLP: Aspiration Toxicity Category 1, STOT Single Exposure Category 3 (narcosis)