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Toxicological information

Genetic toxicity: in vivo

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Administrative data

Endpoint:
in vivo mammalian somatic cell study: cytogenicity / erythrocyte micronucleus
Remarks:
Type of genotoxicity: chromosome aberration
Type of information:
experimental study
Adequacy of study:
supporting study
Reliability:
4 (not assignable)
Rationale for reliability incl. deficiencies:
other: No OECD guideline or GLP defined; no details obout test material purity given; route of administration: intraperitoneal.

Data source

Reference
Reference Type:
publication
Title:
Unnamed
Year:
2007

Materials and methods

Test guideline
Qualifier:
equivalent or similar to
Guideline:
OECD Guideline 474 (Mammalian Erythrocyte Micronucleus Test)
Principles of method if other than guideline:
Seven- to 8 -wk-old male ICR strain mice (weighing 23 + 0.5 g) were aclimatized for at least 7d before being subjected to the Micronucleus (MN) test. Suspension of test compound was treated as follows: group1, vehicle alone (DMSO, negative control); groups 2, 3, 4, and 5 were treated with PA or TPA at 5 concentration levels (20, 100, 500, 2500, or 12500 µM/kg); and group 6 was treated with MMC (positive control, 2 mg/kg) dissolved in sterile deionized water. Animals were administered the test substance ip and were sacrificed 24 h after treatment. Bone marrow was extracted with fetal bovine serum (0.5 ml), and cell suspensions were centrifuged at 1000 x g for 5 min. Cells were then resuspended in residual FBS, spread on slides, and air-dried. The slides were then fixed in methanol for 5 min and stained using a May-Grünwald-Giemsa technique. Slides were observed under an optical microscope at 1000X, and numbers of micronucleated cells were determined by counting numbers of polychromatic erythrocytes (PCE) from among at least 1000 PCE per animal. Micronucleated polychromatic erythrocytes MNPCE) that contained micronuclei were counted from among at least 1000 PCE.
GLP compliance:
not specified
Type of assay:
micronucleus assay

Test material

Reference
Name:
Unnamed
Type:
Constituent
Details on test material:
Phthalic acid [C6H4-1,2-(COOH)2; Cas number 88-99-3]; no details about purity given.

Test animals

Species:
mouse
Strain:
ICR
Sex:
male

Administration / exposure

Route of administration:
intraperitoneal
Duration of treatment / exposure:
Animals were administered the test substance i.p. and were sacrificed 24h after treatment.
Frequency of treatment:
single dose
Post exposure period:
24h
Doses / concentrations
Remarks:
Doses / Concentrations:
20, 100, 500, 2500, 12500 µM/kg)
Basis:
no data
No. of animals per sex per dose:
5
Control animals:
yes

Examinations

Tissues and cell types examined:
Bone marrow was extracted with fetal bovine serum (0.5 ml), and cell suspensions were centrifuges at 1000xg for 5 min. Number of micronucleated cells were determined by counting numbers of polychromatic erythrocytes (PCE) from among at least 1000 PCE per animal.Micronucleated polychromatic erythrocytes (MNPCE) that contained micronuclei were counted from among at least 1000 PCE.

Results and discussion

Test results
Sex:
male
Genotoxicity:
negative
Toxicity:
not specified
Vehicle controls validity:
valid
Negative controls validity:
other: Vehicle control= negative control
Positive controls validity:
valid

Any other information on results incl. tables

Micronucleus Induction in Mouse Bone Marrow Cells Treated with Phthalic Acid:

 Samples  Treatments  Concentrations (µM/kg)  Route  Number of mice tested  Exposure time (h)  MNPCE%a (mean+ SD) PCE/(PCE+NCE)b (mean+SD) 
 Phthalic Acid  Controlc  0  i.p.  5  24  0.24 +0.05  0.11 +0.02
     20  i.p.  5  24  0.32 +0.34  0.15 +0.04
     100  i.p.  5  24  0.38 +0.35  0.13 +0.03
     500  i.p.  5  24  0.41 +0.25  0.16 +0.05
     2500  i.p.  5  24  0.31 +0.55  0.14 +0.02
     12500  i.p.  5  24  0.35 +0.26  0.18 +0.01
   MMCd    i.p.  5  24  6.47 +0.54  0.62 +0.02

aMicronucleated polychromatic erythrocytes/1000 polychromatic erythrocytes, bPolychromatic erythrocytes/1000 erythrocytes, cSample dilution buffer, dMitomycin C.

Applicant's summary and conclusion

Executive summary:

In a Micronucleus Assay in ICR strain mice the animals were injected i.p.with suspensions of test compound, which were treated as follows: group 1, vehicle alone (DMSO, negative control); groups 2, 3, 4, and 5 were treated with Phthalic Acid at 5 concentration levels (20, 100, 500, 2500, or 12500 µM/kg); and group 6 was treated with MMC (positive control, 2 mg/kg) dissolved in sterile deionized water. The animals were sacrificed 24 h after i.p. administration of the test substances. Micronuclei formations due to Phthalic Acid were evaluated using mouse bone marrow at concentrations up to 12500 µM/kg after 24 h of treatment. No mortalities were observed at these levels. Frequencies of MNPCE (micronucleated polychromatic erythrocytes/1000 polychromatic erythrocytes) in the vehicle control groups were 0.14% (PA). In general, MNPCE% was higher for mouse bone-marrow cells treated with the test agent, but no concentration-response relationship was observed. PCE/(PCE+NCE) values were also elevated in cells treated with the test agents, but again no concentration-response relationchip was found.