Talc (Mg3H2(SiO3)4)

Sediment toxicity

Link to relevant study record(s)

Reference

Reference 1

Endpoint:

sediment toxicity: long-term

Data waiving:

other justification

Justification for data waiving:

other:

Reference 2

Endpoint:

sediment toxicity: long-term

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 4.1/ECOSARv1.00

GLP compliance:

no

Remarks:

not applicable. QSAR model

Analytical monitoring:

not required

Vehicle:

no

Test organisms (species):

other: Earthworm

Details on test organisms:

no further information

Study type:

other: QSAR model

Test type:

other: QSAR model

Water media type:

freshwater

Type of sediment:

not specified

Limit test:

no

Duration:

14 d

Exposure phase:

total exposure duration

Hardness:

not applicable to QSAR models

Test temperature:

not applicable to QSAR models

pH:

not applicable to QSAR models

Dissolved oxygen:

not applicable to QSAR models

Salinity:

not applicable to QSAR models

Ammonia:

not applicable to QSAR models

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):

no

Duration:

14 d

Dose descriptor:

LC50

Effect conc.:

313.318 mg/kg sediment dw

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:

LC50 (14-day, earthworm)= 313.318 mg/L (ppm)
1 kg of water has a volume of 1 L and the mg/kg and mg/L are the same.
LC50 (14-day, earthworm)= 313.318 mg/kg soil dw
The ECOSAR QSAR model predicts that 14 -day LC50 value would to be  313.318 mg/L (ppm) for freshwater sediment.Predicted to be non-toxic at the limit of solubility and therefore the substance is non-toxic at the limit of LoS as determined by (Q)SAR

Overview of QSARs estimations on sediment toxicity of  

  Talc (Mg3H2(SiO3)4)

Method	Results	Remarks	Reference
QSAR estimate	LC50 (14-day, earthworm)=313.318 mg/L (ppm)	Reliable with restrictions, QSAR estimated data	ECOSAR Program (v1.00)

 

   

LC50 (14-day, earthworm)= 313.318 mg/L (ppm)

 

Validity criteria fulfilled:

yes

Remarks:

US EPA accepted QSAR method for chemicals properties assessment.

Conclusions:

LC50 (14-day, earthworm)= 313.318 mg/L (ppm)
1 kg of water has a volume of 1 L and the mg/kg and mg/L are the same.
LC50 (14-day, earthworm)= 313.318 mg/kg soil dw
The ECOSAR QSAR model predicts that 14 -day LC50 value would to be  313.318 mg/L (ppm) for freshwater sediment.Predicted to be non-toxic at the limit of solubility and therefore the substance is non-toxic at the limit of LoS as determined by (Q)SAR

Executive summary:

The ECOSAR QSAR model predicts that 14 -day LC50 value would to be  313.318 mg/L (ppm) for freshwater sediment.Predicted to be non-toxic at the limit of solubility and therefore the substance is non-toxic at the limit of LoS as determined by (Q)SAR.

Description of key information

Talc (Mg3H2(SiO3)4) is found abundantly in nature in soils and sediments. The material is an inorganic non-biodegradable substance, retaining its structure in the environment. At normal environmental pH’s this material is stable. In addition it is unlikely through normal use patterns that exposure to natural sediments would occur. Soil and sediment degradation studies are not considered to be applicable as the test material is essentially insoluble in water and consists of materials which occur naturally in these compartments. 

  

The ECOSAR QSAR model predicts that 14 -day LC50 value would to be  313.318 mg/L (ppm) for freshwater sediment. Predicted to be non-toxic at the limit of solubility and therefore the substance is non-toxic at the limit of LoS as determined by (Q)SAR.

Key value for chemical safety assessment

EC50 or LC50 for freshwater sediment:

313.318 mg/kg sediment dw

EC50 or LC50 for marine water sediment:

31.33 mg/kg sediment dw

EC10, LC10 or NOEC for freshwater sediment:

62.66 mg/kg sediment dw

EC10, LC10 or NOEC for marine water sediment:

6.27 mg/kg sediment dw

Additional information

The available data for marine water sediment 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.