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Toxicological information

Repeated dose toxicity: oral

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Administrative data

Endpoint:
repeated dose toxicity: oral
Remarks:
other: acute
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:
1984

Materials and methods

Test guideline
Qualifier:
no guideline followed
Principles of method if other than guideline:
Sixteen Holstein intact male calves averaging 85 kg and 74 days of age were assigned randomly to four dietary lead treatments according to body weight.
GLP compliance:
not specified

Test material

Reference
Name:
Unnamed
Type:
Constituent

Test animals

Species:
cattle
Strain:
other: Holstein Calf
Sex:
male

Administration / exposure

Route of administration:
oral: feed
Vehicle:
not specified
Analytical verification of doses or concentrations:
not specified
Duration of treatment / exposure:
7-wk experimental period
Frequency of treatment:
Twice a day
Doses / concentrations
Remarks:
Doses / Concentrations:
500, 1500, or 4500 ppm Pb as lead sulfate
Basis:
nominal in diet
No. of animals per sex per dose:
4, randomly assigned
Control animals:
yes, plain diet

Results and discussion

Target system / organ toxicity

Critical effects observed:
not specified

Any other information on results incl. tables

There was a linear increase of lead in blood with time on treatment for calves receiving the 500 ppm Pb diet.

Lead in blood of the two calves receiving 1500 ppm added Pb appeared to peak at 4 wk, then remained about the same until the 6th wk. All calves receiving 4500 ppm supplemental lead died within 10 days from onset of the experiment.

From our research and also from review of published data, cattle vary considerably in degrees of toxicity resulting from consuming different amounts of lead from various sources. Differences of published reports may be due to the many variables that may include different chemical forms.

Applicant's summary and conclusion

Conclusions:
Lead sulfate, which is one of the more common environmental pollutants, apparently is less toxic to cattle than some forms that have been studied more.