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Diss Factsheets

Administrative data

Endpoint:
developmental toxicity
Type of information:
experimental study
Adequacy of study:
other information
Reliability:
2 (reliable with restrictions)
Rationale for reliability incl. deficiencies:
other: Acceptable, well-documented publication which meets basic scientific principles

Data source

Reference
Reference Type:
publication
Title:
Unnamed
Year:
1980

Materials and methods

Test guideline
Qualifier:
no guideline followed
Principles of method if other than guideline:
Rat pups were chronically exposed from birth to 40 ppm of Pb and tested behaviorally and biochemically at 25 to 35 days of age.
GLP compliance:
not specified

Test material

Constituent 1
Chemical structure
Reference substance name:
Lead carbonate
EC Number:
209-943-4
EC Name:
Lead carbonate
Cas Number:
598-63-0
Molecular formula:
CH2O3.Pb
IUPAC Name:
λ²-lead(2+) carbonate

Test animals

Species:
rat
Strain:
Sprague-Dawley

Administration / exposure

Route of administration:
oral: feed
Vehicle:
not specified
Analytical verification of doses or concentrations:
not specified
Duration of treatment / exposure:
25 to 35 days
Frequency of treatment:
Rats were given food ad libitum.
Doses / concentrations
Remarks:
Doses / Concentrations:
4% (31.016 ppm)
Basis:
nominal in diet
No. of animals per sex per dose:
8
Control animals:
yes

Results and discussion

Results: maternal animals

Effect levels (maternal animals)

Dose descriptor:
NOAEL
Effect level:
31.016 ppm
Basis for effect level:
other: developmental toxicity
Remarks on result:
not determinable
Remarks:
no NOAEL identified

Results (fetuses)

Details on embryotoxic / teratogenic effects:
Embryotoxic / teratogenic effects:not examined

Fetal abnormalities

Abnormalities:
not specified

Overall developmental toxicity

Developmental effects observed:
not specified

Any other information on results incl. tables

Locomotor activity after chronic postnatal PbCO3 exposure: Pb-exposed rat pups demonstrated locomotor hyperactivity, but the locomotor response to d-amphetamine SO4 (0.5-2.0mg/kg) or apomorphine HCI (0.5-5.0 mg/k) was attenuated.

Prejunctional alterations at DA synapses after chronic postnatal PbCO3 exposure: Synaptosomes from 25-, 30- and 35-day old Pb-exposed rat pups showed the same capacity to synthesize DA as did those obtained from pair-fed control animals.

Accumulation of [3H]DA by rat forebrain slices: No change in the Tissue/Medium ratio for [3H]DA was noted in slices from PbCO3- exposed rat pups.

Postjunctional alterations at DA synapses after chronic postnatal PbCO3 exposure: The activity of adenylate cyclase in the absence of DA or apomorphine (basal activity) was unchanged by chronic PbCO3- exposure.

Applicant's summary and conclusion

Conclusions:
n the conditions of the study, lead carbonate was found toxic to development of rat by causing locomotor activity alterations at chronic doses.

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