2,6-dimethylpyridine

Short-term toxicity to aquatic invertebrates

Link to relevant study record(s)

Reference

Endpoint:

short-term toxicity to aquatic invertebrates

Type of information:

calculation (if not (Q)SAR)

Adequacy of study:

weight of evidence

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

accepted calculation method

Justification for type of information:

Data is from computational model developed by USEPA

Qualifier:

according to guideline

Guideline:

other: Modelling database

Principles of method if other than guideline:

Estimation 48 hrs LC50 value of test chemical on aquatic invertebrates by EPI Suite ECOSAR version 1.11.

GLP compliance:

no

Analytical monitoring:

no

Vehicle:

no

Test organisms (species):

Daphnia magna

Details on test organisms:

TEST ORGANISM
- Common name: Water flea

Test type:

static

Water media type:

freshwater

Total exposure duration:

48 h

Reference substance (positive control):

no

Key result

Duration:

48 h

Dose descriptor:

LC50

Effect conc.:

61.009 mg/L

Nominal / measured:

estimated

Conc. based on:

test mat.

Basis for effect:

mobility

Remarks on result:

other: Neutral Organics

Validity criteria fulfilled:

not specified

Conclusions:

Based on effect of test chemical on the mobility of the test organism Daphnia magna, the 48 hrs LC50 value was estimated to be 61.0 mg/l.

Executive summary:

The short-term toxicity of the test chemical to aquatic invertebrates was predicted using EPI Suite ECOSAR version 1.11. On the basis of effect of test chemical observed in a static system on the mobility of the test organism during the 48 hr exposure duration, the lethal effect concentration (LC50) for the test chemical was estimated to be 61.0 mg/l. Thus, based on the LC50 value, test chemical can be considered as toxic to aquatic invertebrates. Since the test chemical is readily biodegradable in water, test chemical was considered as non-toxic and hence, considered to be 'not classified' as per the CLP classification criteria.

Description of key information

The short-term toxicity of the test chemical to aquatic invertebrates was predicted using EPI Suite ECOSAR version 1.11. On the basis of effect of test chemical observed in a static system on the mobility of the test organism during the 48 hr exposure duration, the lethal effect concentration (LC50) for the test chemical was estimated to be 61.0 mg/l. Thus, based on the LC50 value, test chemical can be considered as toxic to aquatic invertebrates. Since the test chemical is readily biodegradable in water, test chemical was considered as non-toxic and hence, considered to be 'not classified' as per the CLP classification criteria.

Key value for chemical safety assessment

Fresh water invertebrates

Fresh water invertebrates

Effect concentration:

61 mg/L

Additional information

Predicted data of the test chemical and supporting weight of evidence studies for its read across analogue were reviewed for short term toxicity to aquatic invertebrate endpoint which are summarized as below:

 

In a prediction done using EPI Suite ECOSAR version 1.11, the short-term toxicity of the test chemical to aquatic invertebrate was predicted. On the basis of effect of test chemical observed in a static system on the mobility of the test organism during the 48 hr exposure duration, the lethal effect concentration (LC50) for the test chemical was estimated to be 61.0 mg/l. Thus, based on the LC50 value, test chemical can be considered as toxic to aquatic fishes. Since, the test chemical is readily biodegradable in water, chemical was considered as non-toxic and hence, considered to be ‘not classified’ as per CLP classification criteria.

 

In a supporting weight of evidence study from reliable handbook (2009) and secondary source,an acute immobilisation test was conducted for 48 hrs for assessing the effect of test chemical. The study was performed following the principles of the OECD Guideline 202 (Daphnia sp. Acute Immobilisation Test) and EU Method C.2 (Acute Toxicity for Daphnia), respectively under static conditions. Test was carried out using Daphnia magna (Water flea) as a test organism and under test conditions at temperature of 19.1 to 20.1°C, pH 7.7 to 8.6 and hardness of 198 to 208 mg/l as CaCO3, respectively. Test chemical concentrations were determined analytically. Test chemical concentrations used for the study were 10, 20, 40, 80, 160 and 320 mg/l, respectively (nominal conc.). Mean measured conc. used for the study were 10.3, 20, 41.9, 84, 169.5 and 346.5 mg/l (at 0 hr) and 8.3, 17.1, 34.9, 70.5, 139 and 285 mg/l (at 48 hr), respectively. The results of chemical analysis indicated that intended exposure levels were achieved and adequately maintained during the test. At the lowest test concentration, 9.24 mg/l, 5% immobility was seen after 48 hours. The lowest measured concentration at which 100% immobilisation occurred was 153 mg/l. On the basis of the effect of test chemical on mobility of test organism, the 24 hr and 48 hr median effect concentration (EC50) value was determined to be 83.8 and 39.6 mg/l, respectively. Thus, test chemical can be considered as toxic to aquatic invertebrates. Since, the test chemical is readily biodegradable in water, chemical was considered as non-toxic to aquatic invertebrates at environmental relevant concentrations and hence, considered to be ‘not classified’ as per the CLP classification criteria.

 

Another short term toxicity to aquatic invertebrate study was conducted for 48 hrs for assessing the effect of test chemical (J-CHECK). The study was performed in accordance with the OECD Guideline 202 (Daphnia sp. Acute Immobilisation Test). Test was carried out using Daphnia magna (Water flea) as a test organism under static conditions. On the basis of the effect of test chemical on mobility of test organism, the 48 hr median effect concentration (EC50) value was determined to be 34 mg/l. Thus, test chemical can be considered as toxic to aquatic invertebrates. Since, the test chemical is readily biodegradable in water, chemical was considered as non-toxic to aquatic invertebrates at environmental relevant concentrations and hence, considered to be ‘not classified’ as per the CLP classification criteria.

 

On the basis of the above results, test chemical can be considered as toxic to aquatic invertebrate. Since the test chemical is readily biodegradable in water, chemical was considered as non-toxic to aquatic invertebrates at environmental relevant concentrations and hence, considered to be 'not classified' as per the CLP classification criteria.