2-[4-(dimethylamino)phenyl]-3,6-dimethylbenzothiazolium chloride

Biodegradation in water: screening tests

Administrative data

Endpoint:

biodegradation in water: ready biodegradability

Type of information:

experimental study

Adequacy of study:

key study

Study period:

2017

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

2017

Materials and methods

Test guideline

Qualifier:

according to guideline

Guideline:

OECD Guideline 301 B (Ready Biodegradability: CO2 Evolution Test)

GLP compliance:

yes (incl. QA statement)

Test material

Test material information

Constituent 1

Reference substance name:

2-[4-(dimethylamino)phenyl]-3,6-dimethylbenzothiazolium chloride

EC Number:

219-228-9

EC Name:

2-[4-(dimethylamino)phenyl]-3,6-dimethylbenzothiazolium chloride

Cas Number:

2390-54-7

Molecular formula:

C17H19N2S.Cl

IUPAC Name:

2-[4-(dimethylamino)phenyl]-3,6-dimethylbenzothiazolium chloride

Test material form:

solid: particulate/powder

Study design

Oxygen conditions:

aerobic

Inoculum or test system:

activated sludge, domestic (adaptation not specified)

Duration of test (contact time):

28 d

Initial test substance concentration

Initial conc.:

15 mg/L

Based on:

TOC

Parameter followed for biodegradation estimation

Parameter followed for biodegradation estimation:

CO2 evolution

Reference substance

Reference substance:

acetic acid, sodium salt

Results and discussion

% Degradation

Parameter:

% degradation (CO2 evolution)

Value:

ca. -8.33

Sampling time:

28 d

Applicant's summary and conclusion

Validity criteria fulfilled:

yes

Interpretation of results:

not readily biodegradable

Conclusions:

The ready biodegradability of BASIC YELLOW 1 exposed to microorganisms derived from the activated sludge of a municipal sewage treatment was investigated under aerobic static exposure conditions, following the TG OECD 301b according to GLP regulations.
The biodegradation, based on CO2 evolution, of BASIC YELLOW 1 was calculated to be -8.33% after an incubation time of 28 days. Based on the results of this test, it is possible to conclude that BASIC YELLOW 1 isn’t readly biodegradable.
The Reference item Sodium acetate, reached the pass level of 60% (actual value 67.36%) of biodegradation after 14 days, thus confirming suitability of inoculum and test condition.
In the Toxicity control containing both the Test item and reference item, the % of Biodegradation occurred within 14 days was 32.68%, therefore the test item was found to have no inhibiting effect on microbial activity at the concentration used in present study.
The Abiotic sterile control (obtained using a sterilised inoculated solution of HgCl2 [10g/l]), confirmed that the test item was not abiotically degraded.

Executive summary:

The ready biodegradability of BASIC YELLOW 1 exposed to microorganisms derived from the activated sludge of a municipal sewage treatment was investigated under aerobic static exposure conditions, following the TG OECD 301b according to GLP regulations.

The biodegradation, based on CO2 evolution, of BASIC YELLOW 1 was calculated to be -8.33% after an incubation time of 28 days. Based on the results of this test, it is possible to conclude that BASIC YELLOW 1 isn’t readly biodegradable.

The Reference item Sodium acetate, reached the pass level of 60% (actual value 67.36%) of biodegradation after 14 days, thus confirming suitability of inoculum and test condition.

In the Toxicity control containing both the Test item and reference item, the % of Biodegradation occurred within 14 days was 32.68%, therefore the test item was found to have no inhibiting effect on microbial activity at the concentration used in present study.

The Abiotic sterile control (obtained using a sterilised inoculated solution of HgCl2 [10g/l]), confirmed that the test item was not abiotically degraded.