3-hydroxy-2-naphthoic acid

Endpoint summary

Description of key information

BONA is harmful after ingestion. Inconclusive data indicates a possible hazard for skin contact. No data is available for acute inhalation toxicity. 

Key value for chemical safety assessment

Acute toxicity: via oral route

Endpoint conclusion

Dose descriptor:

LD50

Value:

823 mg/kg bw

Additional information

Secondary information indicates that the acute oral LD50 in rats is 823 mg/kg bw and that mortality occurred quickly (within 35-200 minutes) after exposure (Anonymous 2004). Clinical signs occurred within 10 - 30 minutes after exposure.  Reduced activity, prostrate and lateral positioning was observed for 315, 500 and 800 mg/kg bw.  At 1000 and 1250 mg/kg bw reduced activity, prostrate and lateral positioning, accelerated breathing and closure of eyes was observed. These signs were observed until the end of the day of application. Diarrhea was seen in all groups, beginning at 30 to 60 minutes after application. All surviving animals were free of symptoms on day 1 after application. Necropsy findings indicate discoloration of liver in dead animals and hyperaemia and fluid were seen in the gastro-intestinal tracts. Animals that were killed at the end of the observation period were free of pathological changes (Anonymous 2004). It is difficult to assign a specific target organ for acute toxicity from these findings. Although visual effects were observed for liver for deceased rats, it is not clear whether acute liver toxicity is truly the mode of action as it was not observed in surviving animals.

Secondary information is also available regarding acute dermal toxicity (Anonymous 2004). Little detail is available. Considering the low molecular weight of the substance and the irritating properties, systemic availability via skin contact is possible, but the data is considered inadequate for classification and labelling.

Data on acute inhalation toxicity is not available. Based on the low pKa and the eye irritation, BONA is considered to be an irritant to the respiratory system.

Justification for classification or non-classification

Dangerous Substance Directive (67/548/EEC)

The available data are considered reliable and suitable for classification purposes under 67/548/EEC. As a result the substance is considered to be classified for acute oral toxicity under Directive 67/548/EEC, as amended for the 28th time in Directive 2001/59/EC

Classification, Labelling, and Packaging Regulation (EC) No. 1272/2008

The available experimental test data are reliable and suitable for classification purposes under Regulation 1272/2008. As a result the substance is considered to be classified for acute oral toxicity and for respiratory irritation under Regulation (EC) No. 1272/2008. Target organs for acute systemic toxicity could not be identified for the oral route. For the dermal route, insufficient reporting details are available to allow assignment of a target organ. Specific hazard category 3 (Irritation to the respiratory system) is assigned based on pKa and the results of the eye irritation study.