Rifamycin, 3-formyl-

Toxicity to aquatic algae and cyanobacteria

Administrative data

Endpoint:

toxicity to aquatic algae and cyanobacteria

Type of information:

experimental study

Adequacy of study:

key study

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

guideline study with acceptable restrictions

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

2017

Report date:

2017

Materials and methods

Test guideline

Qualifier:

according to guideline

Guideline:

OECD Guideline 201 (Alga, Growth Inhibition Test)

GLP compliance:

no

Test material

Test material information

Constituent 1

Reference substance name:

Rifamycin, 3-formyl-

EC Number:

236-311-5

EC Name:

Rifamycin, 3-formyl-

Cas Number:

13292-22-3

Molecular formula:

C38H47NO13

IUPAC Name:

(7S,9E,11S,12R,13S,14R,15R,16R,17S,18S,19E)-26-formyl-2,15,17,27,29-pentahydroxy-11-methoxy-3,7,12,14,16,18,22-heptamethyl-6,23-dioxo-8,30-dioxa-24-azatetracyclo[23.3.1.1⁴,⁷.0⁵,²⁸]triaconta-1,3,5(28),9,19,21,25(29),26-octaen-13-yl acetate

Sampling and analysis

Analytical monitoring:

no

Remarks:

The analytical method validation was conducted under study 3201267, however, the study was stopped and the analytical procedure was not produced. No supporting chemical analysis was conducted during the range-finding test.

Test organisms

Test organisms (species):

Anabaena flos-aquae

Details on test organisms:

CCAP 1403/13A strain

Study design

Test type:

static

Water media type:

not specified

Limit test:

no

Total exposure duration:

72 h

Post exposure observation period:

No information

Test conditions

Hardness:

Not specified

Test temperature:

22.0-22.7°C

pH:

7.82-8.15 (test start)
7.75-7.92 (test end)

Dissolved oxygen:

Not specified

Nominal and measured concentrations:

Nominal: 0.005; 0.05; 0.5; 5 and 50 mg/mL
Measured: -

Details on test conditions:

Light measurement: 3220-3880 lux

Reference substance (positive control):

no

Results and discussion

Effect concentrations

Effect concentrations 1

Duration:

72 h

Dose descriptor:

EC50

Effect conc.:

ca. 0.131 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

other: yield

Effect concentrations 2

Key result

Duration:

72 h

Dose descriptor:

EC50

Effect conc.:

ca. 0.276 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

growth rate

Details on results:

Due to the difficult/unstable nature of the test substance in the test media, it was decided to stop after the range-finding test. Based on the results of the range-finding test, it was decided to discontinue testing.
Results were therefore determined from the range-finding test.

Applicant's summary and conclusion

Validity criteria fulfilled:

not applicable

Conclusions:

The control validity criteria outlined in the protocol do not apply to range-finding data. It is however determined that growth of algae in the controls and solvent controls was as expected, demonstrating that the test conditions were suitable for the growth of Anabaena flos-aquae.

Based on nominal 3-Formyl Rifamicina SV concentrations, the 72-hour area under the growth curve EbC50, yield EyC50 and growth rate ErC50 were estimated to be 0.131, 0.131 and 0.276 mg/L respectively.