[No public or meaningful name is available]

Toxicity to microorganisms

Link to relevant study record(s)

Reference

Endpoint:

toxicity to microorganisms, other

Remarks:

Study was a toxicity control conducted as part of a CO2 evolution test in accordance with OECD Guideline 301B.

Type of information:

experimental study

Adequacy of study:

key study

Study period:

11 January 2018 to 01 March 2018

Reliability:

1 (reliable without restriction)

Justification for type of information:

Reliable experimental study following OECD 301 guidelines (1992) and EC No. 440/2008 Method C.4-C adopted 2008 and GLP standards.

Qualifier:

according to guideline

Guideline:

other: OECD 301B

Version / remarks:

OECD 301 guidelines (1992)

Deviations:

no

Qualifier:

according to guideline

Guideline:

other: EC No. 440/2008

Version / remarks:

Method C.4-C adopted 2008

Deviations:

no

GLP compliance:

yes (incl. QA statement)

Specific details on test material used for the study:

The test substance is listed as Pentamid™ KH (Methyl N-octadecylterephthalamate). The test substance consists of a solid (100% purity) and was obtained from the Sponsor, Vertellus Holdings LLC and stored at ambient conditions.

Analytical monitoring:

yes

Vehicle:

no

Test organisms (species):

activated sludge of a predominantly domestic sewage

Details on inoculum:

Activated sludge was collected from the Easton Wastewater Treatment Facility, Easton, Maryland on January 08, 2018. The Easton facility treats predominantly residential wastes. The sludge was sieved using a 2-mm screen, adjusted to approximately 1,000 mg total suspended solids/L with mineral media and then aerated at 20 ± 3˚C for approximately 48 hours.

Test type:

static

Water media type:

freshwater

Limit test:

no

Total exposure duration:

46 d

Test temperature:

20 ± 3˚C

pH:

7.51

Nominal and measured concentrations:

The toxicity control was used to evaluate toxicity of the test substance to the inoculum and was dosed with both the reference substance, sodium benzoate (10 mg C/L) and test substance 13.3 mg/L (10 mg C/L) for total of 20 mg carbon/L.

Key result

Duration:

6 d

Dose descriptor:

NOEC

Effect conc.:

13.3 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

other: inhibition of CO2 evolution

Remarks on result:

other:

Remarks:

Toxicity test performed as part of a ready biodegradability CO2 evolution test performed according to OECD 301B and EU C.4-C.

Details on results:

At a test substance concentration of 13.3 mg/L (equivalent to 10 mg C/L) and a reference substance concentration of 10 mg C/L, the toxicity control attained >25% degradation by day 6, thereby confirming that the test substance did not exhibit an inhibitory effect on the sewage treatment micro-organisms used in the test (i.e., test substance and reference substance attained ≥ 25% degradation by Day 14 for the test substance to be considered as non-inhibitory).

Degradation behavior of the toxicity control was normal.

Validity criteria fulfilled:

yes

Remarks:

IC content <5% (protocol ≤ 5%); CO2 emitted by controls <40 mgC/L (protocol <70 mg/L); difference replicates 4.4% (protocol ≤20 %); degradation positive control >60% at 6 d (protocol ≤14 d); degradation toxicity d 6, >25% (protocol ≥25%).

Conclusions:

The test substance is considered as not toxic towards the inoculum at a concentration of 13.3 mg/L. Degradation in the toxicity flask was >25% after 6 days. The guideline indicates that the test item can be considered as toxic towards the inoculum if degradation in the toxicity flask is below 25% at 14 days.

Description of key information

The key study was a toxicity control conducted as part of a CO₂ evolution test in accordance with OECD Guideline 301B. The test substance was shown to be non-inhibitory toward the inoculum at a concentration of 13.3 mg/L. Degradation in the toxicity flask was > 25% at 6 days.

Key value for chemical safety assessment

EC10 or NOEC for microorganisms:

13.3 mg/L