Benzoic acid, 3-[[(2,3-dihydroxypropyl)amino]carbonyl]-5-nitro-

Toxicity to microorganisms

Administrative data

Endpoint:

toxicity to microorganisms, other

Type of information:

experimental study

Adequacy of study:

key study

Study period:

Jan 1996

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

1996

Report date:

1997

Materials and methods

Test guideline

Qualifier:

according to guideline

Guideline:

DIN 38412-8 (Pseudomonas Zellvermehrungshemmtest)

Deviations:

yes

Remarks:

In deviation from the guidelines, nutrient medium according to DIN 38412 Part 8 was not used for the preculture; instead, nutrient medium according to KIELWEIN was used.

GLP compliance:

yes (incl. QA statement)

Test material

Test material information

Constituent 1

Reference substance name:

rac-N-(2,3-Dihydroxypropyl)-5-nitroisophthalamic acid

EC Number:

602-890-1

Cas Number:

122731-58-2

Molecular formula:

C11 H12 N2 O7

IUPAC Name:

rac-N-(2,3-Dihydroxypropyl)-5-nitroisophthalamic acid

Sampling and analysis

Analytical monitoring:

no

Test solutions

Vehicle:

no

Test organisms

Test organisms (species):

Pseudomonas putida

Details on inoculum:

A preculture was set up in nutrient medium 1 day in advance of the actual test, according to KIELWEIN; incubation took place under test conditions; dilution to 10 ± 5 [TE/F] on the day of testing; incubation took place for another 7 ± 1 eh] under test conditions; dilution to 10 ± 5 [TE/F] was carried out with nurient medium according to KIELWEIN

Study design

Test type:

static

Water media type:

freshwater

Limit test:

no

Total exposure duration:

16 h

Test conditions

Details on test conditions:

TEST SYSTEM
- Test vessel: 100 mL
- Type (delete if not applicable): closed
- No. of vessels per concentration (replicates): 3
- No. of vessels per control (replicates): 3

Results and discussion

Effect concentrations

Effect concentrations 1

Key result

Duration:

16 h

Dose descriptor:

EC50

Effect conc.:

650 mg/L

95% CI:

>= 262 - <= 1 612

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

growth inhibition

Effect concentrations 2

Key result

Duration:

16 h

Dose descriptor:

EC10

Effect conc.:

378 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

growth inhibition

Any other information on results incl. tables

Mean values of turbidity (expressed as TE/F) and growth inhibition of Pseudomonas putida as a function of the concentration (n:3) of NIP-Monoamide

Nominal concentration of NIP-Monoamide [mg/I]	TE/F [mean value (16 hours)]	Growth inhibition (%)
Control	77	0
31	77	0
63	92	-20
125	152	-98
250	174	-127
500	31	60
1000	4	96
2000	3	97

Applicant's summary and conclusion

Validity criteria fulfilled:

yes

Conclusions:

The EC50 for growth inhibition of Pseudomonas was calculated to be 650 mg/L [confidence limits (262 - 1612 mg/L)].

Executive summary:

The purpose of this study was to determine the growth inhibition of Pseudomonas putida under exposure of NIP-Monoamide (ZK 39166). The test was conducted in agreement with the DIN standard 38412, L8, "Wachstumshemmtest mit dem Bakterium Pseudomonas putida", March 1991.

The test substance was incubated in an aqueous solution including nutrients with a bacterial population of Pseudomonas putida for a test duration of approximately 16 hours. The tested nominal concentrations were 31, 63, 125, 250, 500, 1000 and 2000 mg/L. Additionally, one control without the test substance was used.

The results indicate that lower concentrations of NIP-Monoamide stimulate the growth of Pseudomonas putida, while concentrations of > 500 mg/L had an inhibitory effect. The remarkable increase of growth in the concentrations of 63 to 250 mg/L could not be explained, since the nutrient medium should be sufficient for an optimal (logarithmic) growth of the controls. In any case, it can be concluded that there was no growth inhibition up to concentrations of 250 mg/L. The EC10 was calculated with 378 mg/L (no confidence limits given). The EC50 was calculated with 650 mg/L [confidence limits (262 - 1612 mg/L)].