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Administrative data

Endpoint:
toxicity to terrestrial arthropods: short-term
Type of information:
experimental study
Adequacy of study:
supporting study
Reliability:
3 (not reliable)
Rationale for reliability incl. deficiencies:
unsuitable test system

Data source

Reference
Reference Type:
publication
Title:
Mutagenicity of sodium azide and its metabolite azidoalanine in Drosophila melanogaster.
Author:
Sadiq M.F., Owais W.M.
Year:
2000
Bibliographic source:
PMID: 10984686, Mutat Res. 469(2):253-7

Materials and methods

Test guideline
Qualifier:
no guideline followed
GLP compliance:
no
Application method:
other: injection

Test material

Constituent 1
Chemical structure
Reference substance name:
Sodium azide
EC Number:
247-852-1
EC Name:
Sodium azide
Cas Number:
26628-22-8
Molecular formula:
N3Na
IUPAC Name:
sodium azide

Sampling and analysis

Analytical monitoring:
no

Test substrate

Vehicle:
yes
Details on preparation and application of test substrate:
0.45 % NaCl saline
application: injection into the animal

Test organisms

Test organisms (species):
Drosophila melanogaster
Animal group:
Diptera (fruit fly (small))
Details on test organisms:
Young wild-type Oregon-k males.

Study design

Study type:
laboratory study
Limit test:
no
Total exposure duration:
24 h
Post exposure observation period:
24h post exposure observation

Test conditions

Test temperature:
25 °C
Details on test conditions:
5, 10, 30, 40 mM Sodium azide in 0.45 % NaCl saline (which also serves as control)
Reference substance (positive control):
no

Results and discussion

Effect concentrationsopen allclose all
Duration:
24 h
Dose descriptor:
LD50
Effect conc.:
ca. 7.6 other: mmol/L
Nominal / measured:
nominal
Conc. based on:
test mat.
Basis for effect:
mortality
Remarks:
: dead flies 24h after exposure
Remarks on result:
other: estimated from the linear range of the dose effect data (5-10 mM) given in Table 1
Duration:
24 h
Dose descriptor:
LD50
Effect conc.:
ca. 0.099 µg per animal
Nominal / measured:
estimated
Conc. based on:
test mat.
Basis for effect:
mortality
Remarks on result:
other: calculated from the data on exposure concentration and volume
Duration:
24 h
Dose descriptor:
LD100
Effect conc.:
>= 40 other: mmol/L
Nominal / measured:
nominal
Conc. based on:
test mat.
Basis for effect:
mortality
Details on results:
24h after injection of 0.2 µL of sodium azide solution into Drosophila melanogaster, their survival was assessed.
Regarding the dose effect curve of the data in Table 1, the LD50 can be estimated to be ca. 7.6 mmol/L, which is equivalent to ca. 0.0988 µg/animal.

Any other information on results incl. tables

Table 1: Survival of Drosophila melanogaster males at 24h following their injection with 0.2 µL sodium azide

Treatment

Concentration [mM]

Survival [%]

NaCl (control)

0

100.0

Sodium azide

5

86.5

10

16.0

30

9.6

40

0.0

Applicant's summary and conclusion

Validity criteria fulfilled:
not specified
Executive summary:

The mutagenic and toxic activities of Sodium azide and its metabolite azidoalanine were examined in the different stages of spermatogenesis in Drosophila melanogaster. Azide was toxic to the injected males with an LD50 of ca. 0.0988 µg/animal. Following the injection with 0.2 µL of these compound in the hemocoel of young adult wild-type males, the minimum concentration with complete toxic effects (zero survival, LD100) was 40 mM sodium azide. Sex-linked recessive lethals were scored by the Muller-5 method in three successive broods, representing sperms (brood A), spermatids (brood B), and a compiled group of meiotic and premeiotic germ cell stages (brood C). The results provide strong experimental evidence that azidoalanine is significantly (p<0.01) mutagenic to all stages of spermatogenesis in Drosophila melanogaster. Sodium azide, however, was not significantly (p>0.05) mutagenic and did not increase the rate of sex-linked recessive lethals over those produced by the control group injected with 0.45% NaCI. These results indicate the requirement of metabolic activation of azide in Drosophila as a prerequisite for its mutagenic effects.