Chromium (III) oxide

Additional information on environmental fate and behaviour

Administrative data

Endpoint:

additional information on environmental fate and behaviour

Type of information:

experimental study

Adequacy of study:

supporting study

Reliability:

3 (not reliable)

Rationale for reliability incl. deficiencies:

other: see 'Remarks'

Remarks:

No endpoints are reported that can be used for hazard assessment of Cr2O3. However, the study contains valuable information on the speciation and fate of chromium in urban areas with high anthropogenic activities.

Data source

Reference

Reference Type:

publication

Title:

Speciation and potential long-term behaviour of chromium in urban sediment particulates

Author:

Byrne, P. et al.

Year:

2017

Bibliographic source:

J Soils Sediments (2017) 17:2666-2676

Materials and methods

Test guideline

Qualifier:

no guideline available

Principles of method if other than guideline:

The study investigated the speciation and long-term fate of chromium in urban sediment particulates with a focus on the major grain types occurring in aquatic and road dust sediments. Speciation of solid-phase chromium in road dust sediments as well as urban aquatic sediments, which is thought to determine the environmental mobility of chromium, was performed using bulk chemical digests, sequential extractions as well as x-ray absorption spectroscopy.

GLP compliance:

no

Test material

Test material information

Constituent 1

Reference substance name:

not applicable

Molecular formula:

Cr

IUPAC Name:

not applicable

Test material form:

other: Elemental Cr in the environment

Results and discussion

Any other information on results incl. tables

Elemental analysis of road dust sediment and aquatic sediment

Cr-bearing grains in road dust sediment were predominantly identified as iron oxide grains, with Cr-bearing silicate glass grains also being present. Mean Cr concentrations in grains derived from road dust sediment were 425 µg Cr/g with maximum concentrations up to 3300 µg/g in these grains. The Cr-bearing grains were further identified Fe oxide, mixed Fe-Al-silicate, Fe-Mg-silicate and Fe-silicate grains.

Aquatic sediment samples were dominated by glass grains with mean Cr concentrations ranging from 226 - 347 µg Cr/g and hotspots (dark inclusions inside Fe-rich glass grains) with a mean Cr concentration of 69800 µg/g. In addition, mean pseudo-total chromium concentrations in glass grains derived from the aquatic sediment samples were determined with 260 µg/g, of which less than 20% was considered bioavailable based on the sequential extraction procedure.

 

Chromium speciation in road dust sediment and aquatic sediments

Based on qualitative XANES analysis, Cr speciation in both road dust sediments and aquatic sediment samples is dominated by Cr(III), with the fraction of tetrahedrally coordinated Cr(VI) species estimated to be < 5%.

Applicant's summary and conclusion

Conclusions:

No endpoints are reported that can be used for hazard assessment of Cr2O3. With its focus only on the >63 µm fraction and microscopic glass grains in the industrial areas of Manchester city, the study is of limited relevance for deriving general fate predictions of chromium substances. However, the study contains valuable information on the speciation of chromium in urban areas with high anthropogenic activities. Cr speciation showed Cr(III) being the dominating species in road dust sediments as well as in the aquatic sediments analysed in this study.