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Please be aware that this old REACH registration data factsheet is no longer maintained; it remains frozen as of 19th May 2023.

The new ECHA CHEM database has been released by ECHA, and it now contains all REACH registration data. There are more details on the transition of ECHA's published data to ECHA CHEM here.

Diss Factsheets

Administrative data

Endpoint:
in vivo mammalian germ cell study: gene mutation
Remarks:
Type of genotoxicity: gene mutation
Type of information:
experimental study
Adequacy of study:
weight of evidence
Reliability:
2 (reliable with restrictions)
Rationale for reliability incl. deficiencies:
other: Similar to guideline study with accepatble restrictions (males are only 24 h old at study initiation).

Data source

Reference
Reference Type:
study report
Title:
Unnamed
Year:
2011

Materials and methods

Test guideline
Qualifier:
equivalent or similar to guideline
Guideline:
OECD Guideline 477 (Genetic Toxicology: Sex-linked Recessive Lethal Test in Drosophila melanogaster)
Deviations:
yes
Remarks:
(males are only 24 h old at study initiation)
GLP compliance:
not specified
Type of assay:
Drosophila SLRL assay

Test material

Constituent 1
Chemical structure
Reference substance name:
2-nitrophenol
EC Number:
201-857-5
EC Name:
2-nitrophenol
Cas Number:
88-75-5
Molecular formula:
C6H5NO3
IUPAC Name:
2-nitrophenol
Details on test material:
- Name of test material (as cited in study report): o-Nitrophenol
No further details are given.

Test animals

Species:
Drosophila melanogaster
Strain:
other: Canton-S wild-type
Sex:
male
Details on test animals or test system and environmental conditions:
TEST ANIMALS
- Age at study initiation: No more than 24 h at the beginning of the treatment.

Administration / exposure

Route of administration:
other: oral (feeding), if no response was obtained the substance was injected in a following experiment
Vehicle:
FEEDING EXPERIMENTS: 5% sucrose solution into which the test chemical was dissolved (solvents included water, ethyl alcohol, or DMSO)
INJECTION EXPERIMENTS: A solution of test chemical dissolved in saline or suspended in peanut oil
Details on exposure:
The test chemical was assayed in the SLRL test by feeding for 3 days to adult Canton-S wild-type males. Toxicity tests were performed to attempt to set concentrations of test chemical at a level that ideally would induce 30% mortality after 72 hours of feeding or 24 hours after injection, while keeping induced sterility at an acceptable level.
Canton-S males were allowed to feed for 72 hours. If no response was obtained, the chemical was retested by injection into adult males. To administer a chemical by injection, a glass Pasteur pipette was drawn out in a flame to a microfine filament and the tip was broken off to allow delivery of the test solution. Injection was performed either manually, by attaching a rubber bulb to the other end of the pipette and forcing through sufficient solution (0.2-0.3 µL) to slightly distend the abdomen of the fly, or by attaching the pipette to a microinjector that automatically delivers a calibrated volume. Flies were anaesthetized with ether and immobilized on a strip of tape. Injection into the thorax, under the wing, is performed with the aid of a dissecting microscope.
Treated males were mated individually to three Basc females for 3 days and given fresh females at 2-day intervals to produce three matings of 3, 2, and 2 days (sperm from successive matings had been treated at successively earlier post-meiotic stages). F1 heterozygous females were mated with their siblings and then placed in individual vials. F1 daughters from the same parental male were kept together to identify clusters. (A cluster occurs when a number of mutants from a given male result from a single spontaneous premeiotic mutation event, and is identified when the number of mutants from that male significantly exceeds the number predicted by a Poisson distribution). If a cluster was identified, all data from the male in question were discarded. Presumptive lethal mutations were identified as vials containing fewer than 5% of the expected number of wild-type males after 17 days; these were retested to confirm the response.
Duration of treatment / exposure:
3 days feeding or single injection, respectively.
Frequency of treatment:
3 days feeding or single injection, respectively.
Post exposure period:
24 hours after injection
Doses / concentrationsopen allclose all
Remarks:
Doses / Concentrations:
400 and 500 ppm
Basis:
other: feeding conc., not further specified
Remarks:
Doses / Concentrations:
2500 and 5000 ppm
Basis:
other: injection conc., not further specified
No. of animals per sex per dose:
no data
Control animals:
other: yes, but not further specified

Examinations

Tissues and cell types examined:
X-chromosomes
Statistics:
SLRL data were analyzed by simultaneous comparison with the concurrent and historical controls (Mason et al., 1992) using a normal approximation to the binomial test (Margolin et al., 1983). A test result was considered positive if the P value was less than 0.01 and the mutation frequency in the tested group was greater that 0.10 %, or if the P value was less than 0.05 and the frequency in the treatment group was greater than 0.15 %. A test was considered to be inconclusive if (a) the P value was between 0.05 and 0.01 but the frequency in the treatment group was between 0.10% and 0.15 %, or (b) the P value was between 0.10 and 0.05 but the frequency in the treatment group was greater than 0.10 %. A test was considered negative if the P value was greater than 0.10 or if the frequency in the treatment group was less than 0.10 %.

Results and discussion

Test results
Sex:
male
Genotoxicity:
negative
Toxicity:
no effects
Vehicle controls validity:
valid
Negative controls validity:
not examined
Positive controls validity:
not examined
Additional information on results:
In some Drosophila SLRL studies, clusters (mutations concluded to result from a single spontaneous pre-meiotic event) in a single male were identified and all the data from that male were excluded from the study analysis. The published reports of these data present the adjusted values. The SLRL data here are uncorrected for the removal of clusters. However, the overall conclusion of the study matches the published conclusion. If one requires access to the corrected data, please refer to the associated journal or contact the NTP for a copy of the printed report.

Any other information on results incl. tables

Tab 1: Drosophila Sex-Linked Recessive Lethal Study Details

Route of

Dose

Percent

Percent

Lethals

Tests

Total Lethals

Total Tests

Percent Lethals

Cluster Removed

Exposure

(ppm)

Mortality

Sterility

Br 1

Br 2

Br 3

Br 1

Br 2

Br 3

Adult Feeding for three days.

500

19

0

0

1

4

838

820

876

5

2534

0.20

N

0

 

 

0

0

2

720

513

695

2

1928

0.10

N

400

33

6

0

0

0

1175

986

791

0

2952

0.00

N

0

 

 

0

1

1

1108

1007

933

2

3048

0.07

N

 

P= 0.426

Adult Injection

5000

9

76

1

0

0

97

66

65

1

228

0.44

N

0

 

 

0

0

0

409

390

326

0

1125

0.00

Y

2500

5

1

1

0

0

2546

1317

1255

1

5118

0.02

N

0

 

 

1

1

8

1941

1378

945

10

4264

0.23

Y

 

P= 0.922

Br = Brood

Applicant's summary and conclusion

Conclusions:
Interpretation of results (migrated information): negative