Platinum

Additional toxicological data

Administrative data

Endpoint:

additional toxicological information

Type of information:

experimental study

Adequacy of study:

key study

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

other: Non-GLP, follows a standard operating procedure, available as an unpublished report, reliable without restrictions

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

2012

Report date:

2012

Materials and methods

Test guideline

Qualifier:

according to guideline

Guideline:

other: Standard Operating Procedure (SOP) prepared by Eurometaux on November 2010

Deviations:

no

Principles of method if other than guideline:

A bio-accessibility testing study has been designed to assay the metal release of Platinum compounds in gastric synthetic media. Metals or metallic compounds are subjected to a media that mimic gastric juice, in terms of pH and body temperature (pH 1.5 and 37 °C), for an exposure time of 1 hour with agitation. Then the compounds are incubated for another hour without agitation, before aliquots are taken, filtered and bio-accessible metal quantified by ICP-MS.

GLP compliance:

no

Test material

Test material information

Constituent 1

Reference substance name:

Platinum

EC Number:

231-116-1

EC Name:

Platinum

Cas Number:

7440-06-4

Molecular formula:

Pt

IUPAC Name:

platinum

Test material form:

solid: particulate/powder

Remarks:

migrated information: powder

Details on test material:

- Name of test material (as cited in study report): Platinum
- Substance type: powder
- Physical state: solid
- Analytical purity: >99.98 % w/w
- Purity test date: 19/04/2010
- Lot/batch No.: REF 2702/PTS 532
- Other: Particle size distribution and specific surface area (BET analysis) values were taken from: Fraunhofer IKTS report N° 4198_4208_4214_4216 of 12.11.2012.
- d50 = 286.262 µm (50th percentile of the particle size cumulative distribution as measured by volume)
- d90 = 810.924 µm (90th percentile of the particle size cumulative distribution as measured by volume)
- BET = 0.08 m2/g

Results and discussion

Any other information on results incl. tables

Table 1. Platinum powder 2 hours bio-elution test in gastric mimetic fluid: Platinum released from blanks and samples at pH 1.5 ( 200 mg/L mass loading), were recorded before the sample was added and after 2 hours of incubation. The results are reported in µg/L and µg/g.

 

	Gastric test parameters				Vessel 1	Vessel 2	Vessel 3	Platinum, µg/L			Platinum, µg/g
Blanks	Time, hr	Temp., °C	O2,mg/L	pH	R1	R2	R3	Mean, µg/L	St. Dev.	CV, %	Mean, µg/g	CV, %
	Before	37.0	6.5	1.50	BDL	BDL	BDL	-	-	-	-	-
	2	37.0	6.5	1.54	BDL	BDL	BDL	-	-	-	-	-
Pt powder	Time, hr	Temp., °C	O2,mg/L	pH	R1	R2	R3	Mean, µg/L	St. Dev.	CV, %	Mean, µg/g	CV, %
	Before	37.0	6.5	1.50	BDL	BDL	BDL	-	-	-	-	-
	2	37.0	6.5	1.52	0.25	0.39	0.45	0.36	0.101	28	1.79	28

CV: corresponds to the coefficient of variation between vessels (the ratio between the standard deviation and the mean of metal released).

BDL: Below detection limit.

 

 

Table 2. Summary of metals solubility from Platinum powder sample; submitted to bio-elution tests in synthetic gastric media. Metal release from the bio-elution tests is reported, as percentage of solubility, after 2 hours of incubation in gastric fluid. SD = Standard Deviation, calculated from the 3 measurements performed to the 3 replica vessels.

 

Sample	% solubility in gastric fluid
	2h	SD
Platinum powder	2x10^-4	1x10^-4

Table 3. Results of the metal release per surface area exposed to the medium. The ratio between metal released in the bio-elution test, expressed in µg/g, and the specific surface area in m²/g are presented for Platinum powder.

Sample	Metal release in gastric fluid [µg/m^2]
	2 h
Platinum powder	22.4

The control standards used to assure the quality of the measurements obtained with ICP-MS, demonstrated an adequate stability and accuracy of the instrument during the metal quantification of the bio-elution samples. All the QC samples showed metal concentration measurements in the range of 20% around the certified value of the standards; criterion used to assure the quality of the measurements.   

Applicant's summary and conclusion

Conclusions:

Platinum powder showed solubility of 2x10-4 % after 2 hours in gastric juice. After incubation in gastric juice, 0.36 µg/L of Pt (1.79 µg/g) was released from samples after 2 hours.

Executive summary:

A study to estimate metal bio-accessibility for Platinum powder in synthetic gastric juice was performed following Standard Operating Procedure (SOP, Eurometaux, November 2010).

 

The test item was subjected to a media that mimic gastric juice, in terms of pH and body temperature (pH 1.5 and 37 °C), for an exposure time of 1 hour with agitation. Then the compounds are incubated for another hour without agitation, before aliquots are taken, filtered and bio-accessible metal quantified by ICP-MS.

Platinum powder showed solubility of 2x10 ^-4 % after 2 hours in gastric juice. After incubation in gastric juice, 0.36 µg/L of Platinum (1.79 µg/g) was released from samples after 2 hours.