Registration Dossier

Administrative data

Description of key information

- Acute oral toxicity: 3210 mg/kg bw (BASF AG, 1981; 79/164)
- Acute dermal toxicity: LD50 > 5000 mg/kg bw (Moreno 1973)

Key value for chemical safety assessment

Additional information

- Acute oral toxicity

In the chosen key study for acute oral toxicity similar to the OECD TG 401, 5 Sprague-Dawley rats per sex per dose group were fasted 15-20 hours prior to oral (gavage) treatment with 4-methoxybenzaldehyde in carboxymethyl cellulose using doses of 464, 2150, 3160, 3830 or 5000 mg/kg bw (BASF AG, 1981; 79/164). A 100% mortality occurred in the high dose group, 70% (2/5 males and 5/5 females) in the 3830 mg/kg bw, 60% (2/5 males and 4/5 females) in the 3160 mg/kg bw and 0% in the 2150 and 464 mg/kg bw dose groups. The LD50 value was calculated to be 3210 (2755 – 3600) mg/kg bw accordingly.

A supporting study reported from secondary source, was conducted according to the OECD TG 401 (Ministry of Health and Welfare Japan, 2001). Five Sprague-Dawley rats per sex and dose group were treated via gavage with 4-methoxybenzaldehyde in corn oil using doses of 0 (males), 1000 (males) or 2000 mg/kg bw (males/females). No deaths occurred and no adverse effects were registered as consequence of the treatment during the observation period or at necropsy. Overall, the LD50 was found to be greater than 2000 mg/kg bw.

Further poorly documented studies for acute oral toxicity are available, showing moderate acute oral toxicity under the given testing conditions. Since the validity of these studies cannot be assessed and a valid key and supporting study with LD50 values >2000 mg/kg bw is available, an overall minimal acute oral toxicity is to be assigned to 4- methoxybenzaldehyde.

 

- Acute inhalation toxicity

In the supportive study, an inhalation hazard test (IHT), male and female rats were exposed to a test atmosphere saturated with vapors of test substance for 7 hours in two consecutive trials with 3 males and 3 females each per trial (BASF AG, 1981; 79/164). The nominal concentration of the test atmosphere determined by differential weighing of the substance before and after the exposure period was approx. 0.32 mg/l air. No mortality resulted from the exposure to the test atmosphere. Snout wiping and attempts to escape were the only signs observed during exposure, and no adverse effects were present at necropsy.

 

No key study is available for acute inhalation toxicity of 4-methoxybenzaldehyde, however, supportive evidence from an inhalation hazard test does not indicate an acute inhalative toxicity of 4-methoxybenzaldehyde, and a study on acute dermal toxicity, covering a relevant route of exposure, is available. In line, no evident acute toxicity has been observed after single oral or dermal administration of 4-methoxybenzaldehyde.

- Acute dermal toxicity

In the chosen key study for acute dermal toxicity, 4-methoxybenzaldehyde was applied to skin sites of 4 rabbit at a dose 5000 mg/kg bw (Moreno, 1973). One of 4 animals died on observation day 1, resulting in a LD50 greater than 5000 mg/kg bw. Overall 4-methoxybenzaldehyde is considered to be non-toxic after single dermal application.

Justification for classification or non-classification

The present data on acute oral toxicity do not fulfill the criteria laid down in 67/548/EEC and regulation (EU) 1272/2008, and therefore, a non-classification is warranted. According to UN-GHS, the test substance needs to be classified as acute oral toxicant (Category 5).

The present data on acute dermal toxicity do not fulfill the criteria laid down in 67/548/EEC and regulation (EU) 1272/2008, and therefore, a non-classification is warranted.