Benzoic acid, 3-amino-5-[[[2,3-bis(acetyloxy)propyl]amino]carbonyl]-2,4,6-triiodo-

Toxicity to microorganisms

Administrative data

Endpoint:

toxicity to microorganisms, other

Type of information:

experimental study

Adequacy of study:

key study

Study period:

Mar 1993 to Dec 1993

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

1994

Materials and methods

Test guideline

Qualifier:

according to guideline

Guideline:

DIN 38412-8 (Pseudomonas Zellvermehrungshemmtest)

Version / remarks:

1992

Deviations:

no

GLP compliance:

yes (incl. QA statement)

Test material

Test material information

Constituent 1

Reference substance name:

rac-5-Amino-N-(2,3-diacetoxypropyl)-2,4,6-triiodoisophthalamic acid

EC Number:

602-891-7

Cas Number:

122731-59-3

Molecular formula:

C15 H15 I3 N2 O7

IUPAC Name:

rac-5-Amino-N-(2,3-diacetoxypropyl)-2,4,6-triiodoisophthalamic acid

Sampling and analysis

Analytical monitoring:

not required

Test solutions

Vehicle:

no

Details on test solutions:

PREPARATION AND APPLICATION OF TEST SOLUTION (especially for difficult test substances)
For the stock solution 12.6 g of ZK 91.248 were dissolved in 1000 mL of bidistilled water. This solution was used for the highest concentration. For the test concentrations, 7500, 5000 and 2500 mg/L of the stock solution were diluted 1:2 and 1:4. 80 mL of the respective solution were filled into the respective test vesseL

Test organisms

Test organisms (species):

Pseudomonas putida

Details on inoculum:

The microorganisms for the pre-culture were taken from a stock up to seven days old, approximately 7 hours before the start of the incubation in the test. They were kept in a pre-culture nutrient solution consisting of 25 mL solution 1.25 mL solution 3 and 50 mL solution 4. 900 mL of sterile dist. water were added. The pre-culture had a turbidity of 0.086 extinction units on the spectrophotometer. This pre-culture was incubated for approximately 7 hours at room temperature. After the incubation period the turbidity of the pre-culture was measured with 0.648 extinction units, and the pre-culture was dissolved to 0.228 (equivalent to approximately TE/F 50) extinction units with the pre-culture medium, ready to be used as inoculum.
2.5 mL nutrient solution 2, 2.5 mL nutrient solution 3, and 5 mL nutrient solution 4, respectively, were added to the 80 mL test substance solutions. Finally, 10 mL of the inoculum were added. Each test concentration and the control without test compound were set up in triplicate. Additionally, one test vessel was used for each test concentration and the control without inoculum in order to analyze the substance-dependent turbidity.

Study design

Test type:

static

Water media type:

freshwater

Limit test:

no

Total exposure duration:

16 h

Test conditions

Test temperature:

room temperature

Nominal and measured concentrations:

Nominal: control, 2500, 5000, 7500 and 10000 mg/L

Details on test conditions:

TEST SYSTEM
- No. of vessels per concentration (replicates): 3
- No. of vessels per control (replicates): 3

EFFECT PARAMETERS MEASURED
The turbidity of the control was measured at 0 and 16 hours, whereas the turbidity of the test solutions was measured only after 16 hours (photometer Methrom 662, light path of 2 cm). Additionally, measurements of the control and the test concentrations without inoculum were performed after 16 hours. All measurements were made at a wavelength of 436 nm.
The measured extinction was transformed to turbidity units (TE/F) according to DIN 38404, part 2, using a calibration table.

Reference substance (positive control):

no

Results and discussion

Effect concentrations

Key result

Duration:

16 h

Dose descriptor:

EC10

Effect conc.:

> 10 g/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

growth inhibition

Applicant's summary and conclusion

Conclusions:

The EC10 of Tamip diacetate (ZK 91.248) was higher than 10 g/L.

Executive summary:

The compound was studied in a microbial growth test with the bacterium Pseudomonas putida according to DIN 38.412, L8. The test was performed under GLP. The microorganisms were incubated with the test substance over a period of 16 hours.The EC10 was higher than 10 g/L.