Naphthenic acids, nickel salts

Additional ecotoxological information

Administrative data

Endpoint:

additional ecotoxicological information

Type of information:

experimental study

Adequacy of study:

supporting study

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

other: Highly relevant and reliable test methods were used to assess nicikel toxicity under field conditions.

Cross-reference

Reason / purpose for cross-reference:

reference to same study

Data source

Reference

Reference Type:

publication

Title:

Nickel phase partitioning and toxicity in field-deployed sediments

Author:

Costello DM, Burton GA, Hammerschmidt CR, Rogevich EC, Schlekat CE

Year:

2011

Bibliographic source:

Environmental Science and Technology. 45:5798-5805

Materials and methods

Test guideline

Qualifier:

no guideline followed

Principles of method if other than guideline:

Sediments from various natural sources were collected, spiked with different nickel levels and equilibrated in the laboratory, and then placed back in the water source with H. azteca to measure in situ toxicity.

GLP compliance:

not specified

Type of study / information:

Toxicity of nickel-spiked sediments to Hyallela azteca

Test material

Test material information

Constituent 1

Reference substance name:

Nickel dichloride

EC Number:

231-743-0

EC Name:

Nickel dichloride

Cas Number:

7718-54-9

Molecular formula:

Cl2Ni

IUPAC Name:

Nickel (II) chloride

Results and discussion

Any other information on results incl. tables

No statistically significant acute toxicity for all sediments tested at nickel concentrations up to 4978 mg Ni/kg dry weight of sediment. Reduced survival, though only marginally significant, was observed on Spring sediments deployed in Spring River and Dow ediments. H. azteca on Spring sediments in Spring River showed declines in survival at medium and high sediment Ni treatments (40 and 47%, respectively) relative to reference and low sediments (93 and 97%, respectively). On Dow sediments, the marginally significant difference between treatments was due to Ni-treated sediments having greater H. azteca survival than reference sediments. Reduced H. azteca survival on Spring sediments, which had one of the lowest inferred binding capacities for Ni, was not unexpected, yet the Spring sediments placed in Little Molasses Creek exhibited no acute toxicity. Statistically insignificant toxicity and inconsistency between streams suggests that these sediments were not acutely toxic. There was no observed change in H. azteca feeding rates for organisms exposed to overlying water. However, feeding rates for H. azteca exposed to low and high treatments in Raisin River (150 and 1140 mg Ni/kg dw, respectively) were 3x higher than organisms on reference sediment. There was no

measured change in the feeding rate of H. azteca exposed to the surface of other sediments. Collectively, the absence of reduced feeding rates and the lack of significant mortality indicate that these Ni-amended sediments are not acutely toxic to caged benthic organisms, although the potential for toxicity is predicted by SEM-AVS theory. However, these sediments do have the potential to negatively affect benthic organisms, and this was observed in the colonizing benthic macroinvertebrate community.

Applicant's summary and conclusion

Conclusions:

Sediments tested were not acutely toxic to H. azteca.

Executive summary:

Study rated by an independent reviewer.