Registration Dossier

Administrative data

Description of key information

Key value for chemical safety assessment

Acute toxicity: via oral route

Endpoint conclusion
Endpoint conclusion:
no adverse effect observed
Dose descriptor:
LD50
Value:
4 000 mg/kg bw
Quality of whole database:
A study initiated with lead di(acetate) trihydrate was performed.

Acute toxicity: via inhalation route

Endpoint conclusion
Endpoint conclusion:
no adverse effect observed

Acute toxicity: via dermal route

Endpoint conclusion
Endpoint conclusion:
no adverse effect observed

Additional information

Acute toxicity, oral

An acute oral toxicity study performed in 1980 with lead di(acetate) trihydrate resulted in an LD50 of >2000 mg/kg bw.

 

Acute toxicity, inhalation

There are not studies on acute inhalation toxicity with lead di(acetate) available. However, read across to lead dichloride is performed and the dossier includes a study with lead monoxide that results in an LC50 of 5000 mg/m3.

Read across from lead monoxide to lead dichloride is justified as follows:

Lead oxide, a material found to have a particle size distribution that would approximate that of other sparingly soluble lead compounds and lead metal powder. Pulmonary deposition modelling further indicated that lead oxide provided a good surrogate for lead di(acetate) in that similar pulmonary deposition patterns, and corresponding local and systemic exposures, would be similar. Read across from lead oxide inhalation data to other compounds is thus scientifically justified and in the interests of animal welfare

Nevertheless, no pulmonary deposition modelling with lead di(acetate) trihydrate is performed. However, based on an LD50 of 182 µm vs. an LD50 of 6.3 µm for lead dichloride (see lead dichloride dossier IUCLID section 4.5) it may safely be assumed that inhalation exposure of lead di(acetate) trihydrate is very low and most of the particles will be swallowed. Hence, exposure of humans via the inhalation route is not likely, since lead di(acetate) is not a powder with an inhalable size.

Acute toxicity, dermal

Acute dermal toxicity studies are not available for lead di(acetate). Nevertheless, the study does not need to be conducted since the substance is neiter acutely toxic via the oral route nor require classification as STOT SE and no systemic effects have been observed in a skin irritation and skin sensitisation study performed with lead di(acetate) trihydrate.

However, there are supporting studies available performed with other lead substances (i.e., dibasic lead phosphite, dibasic lead phthalate, lead monoxide), resulting in an LD50 > 2000 mg Pb/kg bw. In general, read-across to the assessment entities soluble lead substances and soluble acetic acid / salts is applied for the assessment of lead di(acetate) since the ions of lead di(acetate) determine its toxicity to human health. Reliable toxicity data available for soluble lead substances and acetate indicate that the moiety of toxicological concern are lead cations.

 

In conclusion: Although toxic under chronic exposure situations, the acute toxicity of inorganic lead metal compounds appears to be quite low via all exposure routes.

Justification for classification or non-classification

Although toxic under chronic exposure situations, the acute toxicity of lead di(acetate) is predicted to be quite low and does not require classification based on the following:

The data included in this dossier are mostly from soluble lead compounds. Read-across from that lead substances to lead di(acetate) is performed and fully justified (for detailed information please refer to IUCLID section 13.2 “PbAc_Read Across Assessment Framework Report”).

Acute oral toxicity is not observed in animals administered with lead di(acetate) trihydrate after oral exposure. The LD50 is reported to be 4665 mg/kg bw in male and 5610 mg/kg bw in females, leading to an LD50 for lead di(acetate) of > 2000 mg/kg that does not require classification.

For lead di(acetate) exposure of humans via the inhalaiton route is not likely, since lead di(acetate is not a powder with an inhalable size (LD50 182 µm).

Furthermore, since lead di(acetate) is neiter acutely toxic via the oral route nor require classification as STOT SE and in addition no systemic effects have been observed in a skin irritation and skin sensitisation study performed with lead di(acetate) trihydrate, the substance under concern is considered to have a very low potential for dermal toxicity. Hence, no C&L is required.

There is a harmonised classification and labelling available for lead di(acetate) (Regulation (EC) No 1272/2008 Annex VI table 3.1; index no.: 082-005-00-8). However, in accordance with that regulation C&L for acute toxicity, neither for the oral, inhalation nor the dermal route is not required.