Reaction mass of zinc oxide and zinc peroxide

Toxicity to other aquatic organisms

Link to relevant study record(s)

Reference

Endpoint:

toxicity to other aquatic vertebrates

Type of information:

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

Adequacy of study:

key study

Justification for type of information:

REPORTING FORMAT FOR THE ANALOGUE APPROACH

1. HYPOTHESIS FOR THE ANALOGUE APPROACH
The target substance Zinc peroxide and the source substances Zinc oxide, Zinc Chloride, Zinc sulfate, Zinc nitrate are ionic and consist of the Zinc2+ cation and the respective anion.
The read-across is based on the assumption that the zinc cation (as measure for dissolved zinc species) is the determining factor for (eco)toxicity.
For further details, see Justification for read-across attached to IUCLID chapter 13

2. SOURCE AND TARGET CHEMICAL(S) (INCLUDING INFORMATION ON PURITY AND IMPURITIES)
See Justification for read-across attached to IUCLID chapter 13

3. ANALOGUE APPROACH JUSTIFICATION
See Justification for read-across attached to IUCLID chapter 13

4. DATA MATRIX
See Justification for read-across attached to IUCLID chapter 13

Reason / purpose for cross-reference:

read-across: supporting information

Reason / purpose for cross-reference:

read-across source

Reason / purpose for cross-reference:

read-across source

Reason / purpose for cross-reference:

read-across source

Reason / purpose for cross-reference:

read-across source

Reason / purpose for cross-reference:

read-across source

Reason / purpose for cross-reference:

read-across source

Dose descriptor:

NOEC

Effect conc.:

>= 20 - <= 27 µg/L

Conc. based on:

other: Zn2+

Remarks on result:

other: freshwater field studies

Dose descriptor:

NOEC

Effect conc.:

>= 10 - <= 15 µg/L

Conc. based on:

other: Zn2+

Remarks on result:

other: marine field studies

Description of key information

Freshwater: Extensive field data showed that standards for dissolved zinc in freshwater should be in the range 20-27 µg Zn/l (Crane et al. 2007).
Saltwater: Field studies on phytoplancton assemblages dominated by diatoms and dinoflagellates have shown that the lowest observed effect levels are in the range 10-15 µg/L according to an experiment conducted in the English Channel (Davies and Sleep, 1979) and up to >100 µg/L according to another experiment conducted in Kiel Fjord and in the Baltic Sea (Wolter et al. 1984).

Additional information

PNECs for dissolved metals are primarily based on single species data determined in the laboratory. It is important to check their capacity for protecting the environment through field data, making the relationship between measured metal levels and observed ecosystem effects in the field.

freshwater:

Freshwater benthic macroinvertebrates are a group of organisms of known sensitivity to metals.

An extensive dataset on zinc concentrations in UK waters was compared with associated benthic invertebrate community metrics. This large scale study revealed that the freshwater standard for zinc (dissolved) should be in the range 20 -27 µg/l ; it was concluded that the ecotoxicity data (NOECs) were showing the same lower range of sensitivity, and that application of additional safety factors on the ecotoxicity information was overly-conservative, and not reflecting ecological reality.

Marine water:

The available field data relate to algal communities, which are known to be among the most sensitive organisms to zinc in the aquatic environment. The lowest observed effects levels on phytoplancton assemblages are in the range 10 -15 µg/L and EC10 levels from the dose-response curves in the range 7 -13 µg/L according to an experiment conducted in the English Channel (see Davies and Sleep, 1979) and up to >100 µg/L according to another experiment conducted in Kiel Fjord and in the Baltic Sea (see Wolter et al. 1984).