Slags, nickel smelting

Basic toxicokinetics

Administrative data

Endpoint:

basic toxicokinetics in vitro / ex vivo

Type of information:

experimental study

Adequacy of study:

key study

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

other: No GLP but other quality assurance

Cross-reference

Reason / purpose for cross-reference:

reference to same study

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

2010

Report date:

2010

Materials and methods

Principles of method if other than guideline:

Metal release in human digestive system was estimated through in vitro bio-accessibility test in extraction solvent that resembles gastric fluid (using HCl 0.07N at pH 1.5) in accordance with the ASTM D 5517-07 standard. Metal released to the medium were determined after 1 hour of agitation at 171 rpm and another hour to allow the sample to settle at 37°C.

GLP compliance:

no

Remarks:

other quality assurance

Test material

Test material information

Constituent 1

Reference substance name:

Slag, nickel smelting

IUPAC Name:

Slag, nickel smelting

Details on test material:

The following sample was assesed:
Sample Code Sample size Description
4683 Less 500 μm C2 Nickel Slag, Granules

Sample collection made according to the C2-sampling protocol (see IUCLID section 1.4)

Administration / exposure

Vehicle:

other: HCl 0.07N ,pH 1.5

Duration and frequency of treatment / exposure:

1 hour agitation and 1 hour to allow the sample to settle

Results and discussion

Any other information on results incl. tables

Results provide a conservatove estimate of the bioaccesability of metals in nickel slag after ingestion.

Table 1.Bio-elution results of slag samples in gastric mimetic fluid. Test media was HCl 0.07N, pH 1.5 with 200 mg/L sample loading, an agitation rate of 171 rpm and 37°C. MDL= method detection limit (MDL) considering the dilution of the samples at 200 mg/L loading; BDL = Below detection limit (below MDL); Mean = Average concentration; SD = Standard deviation. 

 

Sample	Metal	Bio-elution (200 mg/L), µg/L Mean               CV, %	MDL, µg/L
4883 C2 Slag  granules	Cu	7.8                     10	0.8
	Ni	16.1                    11	0.6
	As	BDL                     -	2
	Pb	BDL                     -	0.4
	Zn	BDL                     -	10
	Cd	0.03                    27	0.02
	Mo	BDL                     -	3
	Co	16.36                    15	0.01

 

Applicant's summary and conclusion

Conclusions:

The study can be used to estimate the amounts of metals in nickel slag that are readily available for absorbtion and support conclusions on hazard classification.

Executive summary:

In-vitro bio-accessibility tests were performed in solvent that resembles gastric fluid ( using HCl at pH 1.5) according to ASTM D5517.07.

The fraction of metals that solubilize under these conditions can be considered as worst case determinant of bio-accessibility of metals contained in the slag. Results demonstrate reduced relative bio- accessibility of metals (Cu 0.04, Ni 0.05, Co 0.06).Dissolved concentrations of Pb and As were below detection limit.