Nickel difluoride

Additional ecotoxological information

Administrative data

Endpoint:

additional ecotoxicological information

Type of information:

migrated information: read-across from supporting substance (structural analogue or surrogate)

Adequacy of study:

supporting study

Study period:

2003-2004

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

other: see 'Remark'

Remarks:

Reliable and relevant with restrictions (Partially fulfills ecotoxicity reliability and relevancy criteria as identified in the attached document, “Criteria for Determining the Reliability and Relevance of Ecotoxicological Data”; attached in the overall endpoint summary for Section 6). Study is well detailed. Rated as a K2 study, rather than K1, because it doesn’t follow the current spiking procedure that is being outlined for NiPERA's sediment testing program.

Cross-reference

Reason / purpose for cross-reference:

reference to same study

Data source

Reference

Reference Type:

publication

Title:

Field measurement of nickel sediment toxicity: role of acid volatile sulfide.

Author:

Nguyen LTH, Burton Jr. GA, Schlekat CE, Janssen CR.

Year:

2011

Bibliographic source:

Environmental Toxicology and Chemistry. V30 (1): p162-p172.

Materials and methods

Principles of method if other than guideline:

Sediments from four freshwater streams or lakes were collected and spiked with nickel, as nickel chloride. Nickel concentrations in spiked sediments were measured. Chemical analyses were undertaken to determine chemical and physical qualities of the sediments and pore-water. After 28 d of equilibration, spiked sediments (plus control sediment collected from the site, with no added nickel) were then returned to their original collection sites. Sediments were stirred and added to colonization trays. Colonization trays were then collected approximately 3 months and 9 months later, at which time a range of benthic indices were measured: abundance, number of taxa, Shannon-Weiner diversity index, taxonomic evenness, percent gastropoda, percent ephemeroptera-plecoptera-tricoptera, percent dominant taxon, biotic sediment index, Biological Monitoring Working Party score, Bray-Curtis dissimilarity index, and benthic indices recommended by the Assessment System for the Ecological Quality of Streams and Rivers throughout Europe using benthic macroinvertebrates. Ecological traits were also used to assess the colonization patterns and adjustment to dominant environmental characteristics at one of the four sample sites. In addition, water-associated toxicity adjacent to the spiked sediment was assessed via in-situ toxicity assays using H. azteca and C. riparius larvae.

GLP compliance:

no

Type of study / information:

Deployment of nickel-spiked sediment and re-colonization of benthic macroinvertebrate community (determined by a range of general benthic indices).

Test material

Test material information

Constituent 1

Reference substance name:

Nickel chloride

EC Number:

253-399-0

EC Name:

Nickel chloride

Cas Number:

37211-05-5

IUPAC Name:

nickel(2+) dichloride

Results and discussion

Any other information on results incl. tables

Chemical analysis:

Total concentrations of nickel in sediments decreased during the nine-month field deployment.

 

In situ toxicity assays:

After 4 d of exposure, survival of H. azteca exposed to the sediment-water interface of nickel experimental trays was not significantly affected (survival was not significantly different, p>0.05, than survival in sediment reference samples).

However, in August 2003, 50 ± 7% survival of C.riparius exposed to the sediment of the Median-Ni treatment (344 µg/g) was observed at the Kraenepoel site, which was significantly lower than survival in the sediment reference samples. The authors note that this could be due to the combination of high pore-water ferrous iron concentrations and low pH.

 

Benthic colonization indices:

The nickel-binding capacity of the sediments was evaluated by measuring the distribution between sediment and pore-water nickel during the colonization period. The results show that the partitioning coefficient Kd (L/kg) at the Schmallenberg site was 2 to 10 times higher than those at the Kraenepoel and Brakel sites. The Kd decreased with increasing sediment nickel concentrations.

Schmallenberg site: No significant difference relative to the reference was detected in colonization of any the nickel-treated sediments.

Kraenepoel site: The experimental trays at the Kraenepoel site were rapidly colonized, with the highest macroinvertebrate abundance noted after one month of colonization compared with the abundances after three and nine months of colonization. No significant effect of nickel on colonization was observed at this site.

Brakel site: The colonization process at the Brakel site also appeared to be successful. However, effects of nickel on the benthic communities were detected at this site during the entire experimental period. In August 2003, benthic macroinvertebrate abundance was significantly reduced in the High-Ni and Median-Ni treatments. Also, in the Low-Ni treatment, fewer Bivalvia were found in comparison with the reference treatment. One third of all calculated benthic indices in the High-Ni treatment were significantly different from those of the reference treatment. In the Median-Ni trays, the Oligochaeta abundance was significantly reduced. Significantly higher indices of diversityand evenness in comparison with the reference and other nickel treatments, however, were noted at Median-Ni. In April 2004, a significant effect on benthic abundance and community structure (i.e., 10/13 indices were significantly different from the reference) occurred in the High-Ni and Median-Ni treatments.

Pallanza site: In August and October 2003, only a few invertebrates (7-14 individuals/tray) and two to three taxa were found in all experimental trays. The macroinvertebrate abundance and community structure in the reference sediment were not significantly different from those exposed to nickel-spiked sediments. In spring 2004, the benthos density, number of taxa, Bray-Curtis, and the Biological Monitoring Working Party indices in both Median-Ni and Low-Ni treatments were significantly different from those in the reference.

Applicant's summary and conclusion

Conclusions:

The authors concluded that uncertainty about the presence and absence of nickel toxicity occurred at [Simultaneously extracted metals (SEM) – acid volatile sulfide (AVS)] and [(SEM - AVS)/ normalized to a fraction of organic carbon (foc ) ]between 0.4 to 2 µmol/g and 21 to 700 µmol/g OC, respectively.

Executive summary:

Study rated by an independent reviewer.