Silicic acid, aluminum magnesium sodium salt

Additional toxicological data

Administrative data

Endpoint:

additional toxicological information

Type of information:

experimental study

Adequacy of study:

key study

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

other: Test procedure in accordance with national standard methods with acceptable restrictions.

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

2009

Report date:

2009

Materials and methods

Type of study / information:

The bioavailability of silicic acid aluminium magnesium sodium salt was investigated in an artifical test system of the digestive tract.

Test guideline

Qualifier:

equivalent or similar to guideline

Guideline:

other: DIN 19738: Resorptionsverfügbarkeit von organischen und anorganischen Schadstoffen aus kontaminiertem Bodenmaterial", July 2004

Deviations:

yes

Remarks:

- determination of Mg via titration; lower temperature for the 2nd test

GLP compliance:

yes (incl. QA statement)

Remarks:

12.01.2007

Test material

Test material information

Constituent 1

Reference substance name:

Silicic acid, aluminum magnesium sodium salt

EC Number:

234-919-5

EC Name:

Silicic acid, aluminum magnesium sodium salt

Cas Number:

12040-43-6

Molecular formula:

Na(0.017-1.739)Mg(0.008-0.823)Al(0.002-0.2473)SiO(2.018-3.837)

IUPAC Name:

aluminium(3+) magnesium(2+) sodium tris(oxosilanebis(olate))

Test material form:

solid: particulate/powder

Specific details on test material used for the study:

- Name of test material (as cited in study report): Durafill 200 (Sodium magnesium aluminium silicate)
- Analytical purity: SiO2: 81%; Al2O3: 8.5 %; MgO: 2%
- Other: All samples were processed in April 2009.

Results and discussion

Any other information on results incl. tables

Concentration in samples

Sample	1	2	mean	SD	RSD
concentration of Mg in mg/L	69.7	62.3	66.0	5.2	7.9%
concentration of Al in mg/L	< 0.2	< 0.2	< 0.2	-	-

Concentration in blanks

Sample	blank 1	blank 2
concentration of Mg in mg/L	17.4	9.4
concentration of Al in mg/L	< 0.2	< 0.2

Differences, samples - blank1

Sample	1	2	mean	SD	RSD
concentration of Mg in mg/L	52.3	44.9	48.6	5.2	10.8%
concentration of Al in mg/L	< 0.2	< 0.2	< 0.2	-	-

Mobilised masses and bioavailability of Mg

Sample	1	2	mean	SD	RSD
Mobilised masses of test item µg/g	5230.0	4490.0	4860.0	523.3	10.8%
Bioavailability %	42.87%	36.8%	39.84%	4.29%	10.8%

The mobilised masses of aluminium were 0%, because no Al was detecatable in all solutions.

The bioavailability of Mg was 39.8 %, with a relative standard deviation of 10.8%. It should be kept in mind that the different components of the test item have different solubilities in aqueous solutions. Sodium is probably dissolved completely, whereas aluminium could not be detected in the solutions. Therefore, bioavailability must in this case always be reported in reference to the analysed ion.

Applicant's summary and conclusion

Conclusions:

Due to the low water solubility of test item only part of the substance can be solved in aqueous solutions, Al ions are even not detectable.
Only Mg ions could be used for determination of bioavailbility: 39.84%