Talc (Mg3H2(SiO3)4)

Short-term toxicity to aquatic invertebrates

Link to relevant study record(s)

Reference

Reference 1

Endpoint:

short-term toxicity to aquatic invertebrates

Remarks:

Q)SAR calculated endpoint

Type of information:

(Q)SAR

Adequacy of study:

key study

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

results derived from a valid (Q)SAR model and falling into its applicability domain, with adequate and reliable documentation / justification

Justification for type of information:

QSAR prediction: US EPA accepted QSAR method for chemicals properties assessment.

Qualifier:

according to guideline

Guideline:

other: QSAR model

Principles of method if other than guideline:

EPI Suite v 4.0/ECOSARv1.00

GLP compliance:

no

Remarks:

not applicable. QSAR model

Analytical monitoring:

not required

Vehicle:

no

Test organisms (species):

other: Daphnid species

Test type:

other: QSAR model

Water media type:

freshwater

Limit test:

no

Total exposure duration:

48 h

Hardness:

not applicable. QSAR model

Test temperature:

not applicable. QSAR model

pH:

not applicable. QSAR model

Dissolved oxygen:

not applicable. QSAR model

Salinity:

not applicable. QSAR model

Nominal and measured concentrations:

not applicable. QSAR model

Details on test conditions:

Chem Name : Talc (Mg3H2(SiO3)4)
Molecular Wt: 379.27
Henry's LC : 5.54e-029 atm-m3/mole (calc VP/Wsol)
Vapor Press : 1.11e-022 mm Hg (Mpbpwin program)
Liquid VP : 1.15e-019 mm Hg (super-cooled)
Melting Pt : 330 deg C (Mpbpwin program)
Log Kow : -9.4 (Kowwin program)
Soil Koc : 31.82 (KOCWIN MCI method)

Reference substance (positive control):

not required

Duration:

48 h

Dose descriptor:

LC50

Effect conc.:

36 812.359 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

other: (Q)SAR prediction

Remarks on result:

other: non-toxic , as determined by (Q)SAR

Details on results:

The ECOSAR QSAR model predicts that LC50 for fresh water species Daphnid would to be 36812.359 mg/l .This result signifies that the test substance is not expected to be toxic

Reported statistics and error estimates:

Daphnid, 30-day, ChV (chronic value) =  1459.798mg/L (ppm)

Overview of QSARs estimations on short-term aquatic toxicity of Talc (Mg3H2(SiO3)4) to Daphnid

 

Method	Results	Remarks	Reference
QSAR estimate	Daphnid , 48-hr LC50 =36812.359 mg/L (ppm)   Daphnid, 30-day, ChV (chronic value) = 1459.798 mg/L (ppm)	Reliable with restrictions, QSAR estimated data	ECOSAR Program (v1.00)

Using the EPIWIN ECOSAR QSAR model aLC50 for fresh water Daphnid of  36812.359 mg/l was established. 

 Daphnid , 48-hr LC50 = 36812.359 mg/L (ppm)  

Daphnid, 30-day, ChV (chronic value) =  1459.798mg/L (ppm)

This result signifies that the test substance is not expected to be toxic.

Validity criteria fulfilled:

yes

Remarks:

US EPA accepted QSAR method for chemicals properties assessment.

Conclusions:

The ECOSAR QSAR model predicts that LC50 for fresh water species Daphnid would to be 36812.359 mg/l .This result signifies that the test substance is not expected to be toxic

Executive summary:

The ECOSAR QSAR model predicts that LC50 for fresh water species Daphnid would to be 36812.359 mg/l .This result signifies that the test substance is not expected to be toxic

Reference 2

Endpoint:

short-term toxicity to aquatic invertebrates

Data waiving:

study scientifically not necessary / other information available

Justification for data waiving:

the study does not need to be conducted because the substance is highly insoluble in water, hence indicating that aquatic toxicity is unlikely to occur

other:

Description of key information

The substance is inorganic almost insoluble powder in aqueous solution and Talc (Mg3H2(SiO3)4) is not expected to be harmful to aquatic life. The material is non-biodegradable, retaining its structure in the environment. At normal water course pH’s this material is stable. It does not hydrolyze in water .The majority of the applications for which this substance is used will not result in the material being released to water courses directly. If low concentrations do get through the water treatment process and enter the water course, the fact that the material does not biodegrade, is stable, not hydrolyses suggest that transfer across biological membranes is unlikely. Short term aquatic toxicity tests reported in the literature (LC50 Brachydanio rerio (Zebra fish) >100000 mg/L/24 hr; for Talc) show this substance is not toxic to aquatic life. On this basis the need for short term aquatic testing is waived. On this basis, the need for further testing for this end point has been waived and being unnecessary and scientifically unjustified.

 

The ECOSAR QSAR model predicts that LC50 for fresh water species Daphnid would to be 36812.359 mg/l .This result signifies that the test substance is not expected to be toxic

Key value for chemical safety assessment

Fresh water invertebrates

Fresh water invertebrates

Effect concentration:

36 812.359 mg/L

Marine water invertebrates

Marine water invertebrates

Effect concentration:

3 681.24 mg/L

Additional information

The available data for marine water Daphnid are limited and to obtaine the value for PNECs for saltwaters is taken account a assesment factor 10 to extrapolate to LC50 following the “Guidance on Information Requirement and Chemical Safety Assessment R.10: Characterisation of dose [concentration]- response for environment”and “Table R.10-5 Assessment factors proposed for deriving PNEC water for saltwater for different data sets”, to account for the possibility that greater taxonomic diversity in the marine environment makes it likely that some marine taxa may be more sensitive than the most sensitive freshwater taxa.