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Description of key information

Key value for chemical safety assessment

Acute toxicity: via oral route

Endpoint conclusion
Dose descriptor:
LD50
Value:
4 665 mg/kg bw

Additional information

Decision:Weight of evidence (grouping) based on information published in scientific journals (Ref.1-4)

 

Compound

Solubility in water (20°C)

Species

Route

Type

GLP

Result

Remark

Ref.

Pb(NO3)2

522 g/L

(SDB)

Mouse

i.p.

LD50

No

74 mg/kg

Details of toxic effects not reported other than lethal dose value

5

Pb(NO3)2

522 g/L

(SDB)

Rat

i.v.

LD50

No

93 mg/kg

Details of toxic effects not reported other than lethal dose value

6

Pb(NO3)2

522 g/L

(SDB)

Guinea pig

i.p.

TDLo

No

500 mg/kg

Behavioural:Convulsions or effect on seizure threshold

Blood:Pigmented or nucleated red blood cells

Nutritional and Gross Metabolic:body temperature decrease

7

Pb(NO3)2

522 g/L
(SDB)

Rat

Not reported

LD50

No

3613 mg/kg

Details of toxic effects not reported other than lethal dose value

2

PbF2

0.65 g/L
(SDB)

Rat

p.o.

LD50

No

3031 mg/kg

Details of toxic effects not reported other than lethal dose value

4

PbSO4

42.5 mg/L
(CRC Handbook)

Guinea pig

p.o.

LDLo

No

30 g/kg

Behavioural: Convulsions or effect on seizure threshold

Blood: Pigmented or nucleated red blood cells

8

Pb(Ac)2x3H2O

625 g/L

Rat

p.o.

LD50

No

4665 mg/kg

Details of toxic effects not reported other than lethal dose value

1

PbO

17.2 mg/L (IUC4)

Rat

p.o.

LD50

No

>10000 mg/kg

Sprague Dawley rats (15m/15f), dose 6350, 7900 and 10000 mg/kg given to 5m/5f for each dose, test item mixed with 1% carboxycellulose gel,
no effects after 7 days observation

9

PBCl2

10 g/L
(SDB)

Rat

p.o.

LD50

No

>1946 mg/kg

Details of toxic effects not reported other than lethal dose value

3

Lead is a classical chronic or cumulative poison. In general soluble lead salts show lowest observed lethal doses in animals after oral exposure to lead acetate, lead chlorate, lead nitrate, lead oleate, lead oxide, and lead sulfate range from 300 to 10000 mg/kg bw, The wide range is attributable to differences in absorption of the various lead salts and thus differences in exposure.

To the best of our knowledge, there are no data from OECD guideline studies for lead dinitrate available. However, the acute oral toxicity data published for similar water soluble lead salts indicate a low acute toxicity potential (LD50 > 2000 mg/kg). Lower values are only obtained using other routes of administration (e.g. i.p. or i.v. application). Comparing the water solubility, lead acetate and lead dinitrate show very similar values. Acute toxicity data published for both salts are in the same order of magnitude. However, the study on lead dinitrate does not provide information on the route of administration, limiting the reliability of the study record.2

Lowering the solubility of the inorganic compounds (PbSO4, PbO) reduces the bioavailability and thus leads to lower acute toxicity values, while increasing solubility (PbCl2) slightly increases the acute toxicity.

From these considerations it appears that the toxicity of lead salts is triggered by the lead cation rather than the corresponding anion. Therefore, it is considered justified to use data from lead acetate as key study also for other soluble lead salts like lead dinitrate. As the molar mass of lead acetate and lead dinitrate is almost identical, the LD50 value for lead acetate is thus also applicable for lead dinitrate.

Using read across from these data we conclude, that the acute toxicity potential of lead dinitrate is low (> 2000 mg/kg bw).

 

 

1.            Journal of the American College of Toxicology, Part B.1992,1, 713.

2.            GISAAA Gigiena i Sanitariya,.1985,50, (3), 57.

3.            Holbrook, D. J., Jr.; Washington, M. E.; Leake, H. B.; Brubaker, P. E., Studies on the evaluation of the toxicity of various salts of lead, manganese, platinum, and palladium.Environmental Health Perspectives1975,10, 95-101.

4.            Gigiena Truda i Professional'nye Zabolevaniia. Labor Hygiene and Occupational Diseases.1985,35, (8), 43.

5.            Garber, B.; Wei, E.; Fried, J. F.; Rosenthal, M. W.; Schubert, J., Lead toxicity in mice with genetically different levels of delta-aminolevulinic acid dehydratase

Induced accumulation of citrate in therapy of experimental lead poisoning.Bull Environ Contam Toxicol1973,9, (2), 80-3.

6.            Fried, F. F.; Rosenthal, M. W.; Schubert, J., Induced accumulation of citrate in therapy of experimental lead poisoning.Proc Soc Exp Biol Med1956,92(2), 331-3.

7.            Archiv für Hygiene und Bakteriologie.1941,125, 273.

8.            Archiv für Hygiene und Bakteriologie1941,125, 273.

9.            Laboratorium für Pharmakologie und Toxikologie HamburgIUCLID PbO (CAS 1317-36-8), 2000; 1972.

 

 

Justification for classification or non-classification

Published information for soluble lead salts clearly shows that the LD50 (oral) of these compounds is above 2000 mg/kg body weight. Lead acetate basic and lead acetate dibasic belongs to this group of water soluble lead salts, thus indicating that the LD 50 is above 2000 mg/kg bw. This read across is supported by published information in lead acetate.

Taking these findings into account, lead acetate basic and dibasic do not need to be classified according to 67/548/EC and CLP. However, according to the group entry for lead compounds in Annex I of 67/548/EC, lead salts maybe classified as acute toxic category 4.