Bis(D-gluconato-O1,O2)zinc

Ecotoxicological Summary

Hazard for aquatic organisms

Freshwater

Hazard assessment conclusion:

PNEC aqua (freshwater)

PNEC value:

54.4 µg/L

Assessment factor:

1

Extrapolation method:

assessment factor

Marine water

Hazard assessment conclusion:

PNEC aqua (marine water)

PNEC value:

42.5 µg/L

Assessment factor:

1

STP

Hazard assessment conclusion:

PNEC STP

PNEC value:

362.4 µg/L

Assessment factor:

100

Sediment (freshwater)

Hazard assessment conclusion:

PNEC sediment (freshwater)

PNEC value:

341.5 mg/kg sediment dw

Assessment factor:

1

Sediment (marine water)

Hazard assessment conclusion:

PNEC sediment (marine water)

PNEC value:

188.9 mg/kg sediment dw

Assessment factor:

1

Hazard for air

Air

Hazard assessment conclusion:

no hazard identified

Hazard for terrestrial organisms

Soil

Hazard assessment conclusion:

PNEC soil

PNEC value:

181.2 mg/kg soil dw

Assessment factor:

1

Hazard for predators

Secondary poisoning

Hazard assessment conclusion:

no potential for bioaccumulation

Additional information

For deriving PNEC, care was taken because of the ionisable organo-metallic property of the substance, as results could express different toxicities. As outlined by the technical guidance of ECHA, acute test does not provide a complete measure of toxicity for such substances. Consequently, PNEC are based on the PNEC derived in the EU RAR documents on Zinc metal zinc sulphate and zinc chloride.

In the EU RAR documents, PNEC value are derived taking into account several studies based on zinc acute and chronic toxicity and taking into account the environmental fate and pathways. In order to establish a complete classification with the more relevant and reliable data, the EU RAR documents (cf. references) on zinc sulphate and zinc metal were used, as a continuation of the read-across approach used.

 

The value of PNEC are presented in the following table:

 

Environmental compartment	PNEC value, as Zn (dissolved zinc)
Freshwater (Hardness > 24 mg/L, as CaCO3)	7.8 μg/l
Freshwater (Hardness <24 mg/L, as CaCO3)	3.1 μg/l
Freshwater sediment	49 mg/kg dwt 11 mg/kg wwt
STP effluent	52 μg/l
Soil	26 mg/kg dwt 23 mg/kg wwt

 

For applying the in the risk assessment of zinc digluconate, these value are converted using the molecular weight of zinc (M_Zn=65.39) and zinc digluconate (M_Zn-Glc=455.682). The following values are selected:

Environmental compartment	PNEC value, as Zn (dissolved zinc)
Freshwater (Hardness > 24 mg/L, as CaCO3)	54,4 μg/l
Freshwater (Hardness <24 mg/L, as CaCO3)	21,6 μg/l
Freshwater sediment	341,5 mg/kg dwt 76,7 mg/kg wwt
STP effluent	362,4 μg/l
Soil	181,2 mg/kg dwt 160,3 mg/kg wwt

 

   

Ref:

European Union Risk Assessment Report ZINC METAL, 2010 (EUR 24587 EN – 2010)

European Union Risk Assessment Report ZINC SULPHATE, May 2008 (R076_0805_env)

European Union Risk Assessment Report ZINC CHLORIDE, May 2008 (R075_0805_env)

Conclusion on classification

Acute aquatic toxicity:

The following key values for chemical safety assessment were selected:

Taxonomic groups	“Species mean” NOEC values (μg/l)
Fish	EC-96h = 11.12 mg/L
crustacea	EC50-48h = 22.8 mg/L
algae or other aquatic plants	EC50 -72h = 0.26 mg/L

 

Considering that:

- 96 hr LC50 (for fish) > 1 mg/l

- 48 hr EC50 (for crustacea) > 1 mg/l

- 72 or 96 hr ErC50 (for algae or other aquatic plants) < 1 mg/l (determined at 0.26mg/l)

the substance is classified as Category 1 regarding acute aquatic toxicity to the environment.

 

The M Factor is set according to the table 4.1.3 of the annex I of CLP regulation. The EC50 value used is included in the following interval : 0,1 < L(E)C50 ≤ 1. Consequently the corresponding M factor is 1.

 

 

Chronic aquatic toxicity:

Since the REACH registration dossier submitted have been made in view of 10-100T/y, no chronic data were reported. In order to establish a complete classification with the more relevant and reliable data, the EU RAR documents (cf. references) on zinc sulphate, zinc chloride and zinc metal were used, as a continuation of the read-across approach used.

According to Annex I: 4.1.1.2.2 of CLP regulation, “both freshwater and marine species toxicity data are considered suitable for use in classification provided the test methods used are equivalent.” Therefore, the main value used and summarized in the EU RAR document (zinc metal) for fresh and marine water are reported in the two tables below:

 

Table 1 - Species mean” NOEC values that are used as input values for deriving the 5th percentile values as a basis for the freshwater PNEC_aquaticin the EU RAR documents.

Taxonomic groups (freshwater)	“Species mean” NOEC values (μg/l)
Algae (unicellular)	17
Algae (multicellular)	60
Poriferans	43; 43; 43; 65
Molluscs	75; 400
Crustaceans	37; 42; 88
Insects	137
Fish	44; 50; 78; 189; 530; 660

 

Table 2 - “Species mean” NOEC values that are used as input values for deriving the 5th percentile values as a basis for the saltwater PNEC_aquaticin the EU RAR documents.

Taxonomic groups (marine water)	“Species mean” NOEC values (μg/l)
Algae (unicellular)	10; 10; 10, 15; 15; 20; 32; 100; 100; 100; 140; 200; 500; 2700
Algae (multicellular)	100
Coelenterates	300
Annelids	100; 100; 100; 320
Molluscs	19; 50; 50; 1000
Crustaceans	18; 120; 440
Echinoderms	10

 

Considering the most sensitive specie during chronic exposure, as presented in the tables above (algae unicellular or Echinoderms), the NOEC used for classification is stated as 10 µg/L (or 0.01mg/L).

Considering that the substance is rapidly biodegradable, and according to the table 4.1.0 of the annex I of CLP regulation, the substance should be considered as classified in the Category Chronic 1 since Chronic NOEC (for algae or other aquatic plants)£0,01 mg/l.

The M Factor is set according to the table 4.1.3 of the annex I of CLP regulation. The NOEC value used is included in the following interval: 0,001 < NOEC ≤ 0,01. Consequently, the corresponding M factor for rapidly degradable substance is 1.

 

Finally, the classification considered for Chronic aquatic toxicity is the following: Category Chronic 1 (H410) ; M factor = 1.

Refrences:

European Union Risk Assessment Report ZINC METAL, 2010 (EUR 24587 EN – 2010)

European Union Risk Assessment Report ZINC SULPHATE, May 2008 (R076_0805_env)

European Union Risk Assessment Report ZINC CHLORIDE, May 2008 (R075_0805_env)