Camphene

Endpoint summary

Description of key information

Acute toxicity: oral: Weight of evidence: Experimental results from different independent sources in two species (rat and mouse) and read-across from the analogue 5-ethylidene-8,9,10-trinorborn-2-ene (experimental results from different independent sources). The acute oral LD50 value is always reported to be greater than 2000 mg/kg bw.
Acute toxicity: dermal: Weight of evidence: Experimental results from different independent sources in rabbits and read-across from the analogue 5-ethylidene-8,9,10-trinorborn-2-ene. A route-to-route extrapolation from the oral to the dermal route is also provided. The acute dermal LD50 value is always reported to be greater than 2000 mg/kg bw.
Acute toxicity: inhalation: key study: Based on available guidelines on route-to-route extrapolation of toxicity data when assessing health risks of chemicals, an extrapolation based on the acute oral toxicity data is calculated for the inhalation route. The 4 -h LC50 would be greater than 25 mg/l.

Additional information

The substance Camphene is used in Cosmetics. The Cosmetics Directive foresees a regulatory framework with the aim of phasing out animal testing. It establishes a prohibition to test finished cosmetics products and cosmetics ingredients on animals (testing ban). The testing ban on ingredients applies since 11 March 2009. In order to comply with the information requirements established by the REACH Regulation, available data from literature and alternative methods such as read-across and route-to-route extrapolation are included.

Acute toxicity: oral:

Weight of evidence: Experimental results from different independent sources in two species (rat and mouse) and read-across from the analogue 5-ethylidene-8,9,10-trinorborn-2-ene (experimental results from different independent sources). The acute oral LD50 value is always reported to be greater than 2000 mg/kg bw.

Acute toxicity: dermal:

Weight of evidence: Experimental results from different independent sources in rabbits and read-across from the analogue 5-ethylidene-8,9,10-trinorborn-2-ene. A route-to-route extrapolation from the oral to the dermal route is also provided. The acute dermal LD50 value is always reported to be greater than 2000 mg/kg bw.

Acute toxicity inhalation:

Key study: Based on available guidelines on route-to-route extrapolation of toxicity data when assessing health risks of chemicals, an extrapolation based on the acute oral toxicity data is calculated for the inhalation route.

From the available data on the acute oral toxicity data, it is concluded that the oral LD50 for the substance Camphene is greater than 5000 mg/kg bw. As recommended in the corresponding guidelines, where data from the oral route is being used as the starting point, if no data are available on oral bioavailability, it is appropriate to assume that 100% of an orally administered dose is systemically available. Since no data is available on inhalation absorption, the most precautionary default would be to assume 100% absorption by this route.

Based on this acute oral toxicity data, an oral NOAEL may be identified as greater than 5000 mg/kg bw. This NOAEL can be modified into an inhalation NOAEL using a route-to-route extrapolation based on the assumptions stated above. Taking into account an exposure of 4 hours for the acute inhalation toxicity study, the value of 5000 mg/kg bw is divided by the default physiological parameter under the allometric scaling principle which is approximately 0.2 m3/kg bw for rats. This extrapolation leads to a value of 25000 mg/m3 (25 mg/l). Therefore, the 4 -h LC50 would be greater than 25 mg/l.

Justification for classification or non-classification

Based on the results reported for the acute toxicity, the substance is not classified.