hydronium;iron(3+);hexahydroxide;disulfate

Short-term toxicity to fish

Description of key information

No relevant effects

Additional information

This endpoint is covered by the category approach for dissociating, inorganic and non-toxic iron compounds (please see the section on physical and chemical properties for the category justification/report format).

Testing for this endpoint has been waived in accordance with column 2 and Annex XI, part 1 and 2, restrictions.

Information from Literature Searches and earlier Assessment Approaches

The literature reviews of Vangheluwe & Versonnen (2004), Johnson et al. (2007) and OECD (2007) revealed some data. The results of the studies, selected as “reliable” by the respective authors are listed in the following tables. Nonetheless the experiments must be rated “not reliable” (Klimisch 3) according to the Klimisch et al. (1997) scale due to methodological objections against testing of aquatic organisms as concluded in the beginning of this chapter (section „Ecotoxicological information“). True, intrinsic toxicity of iron kations in aerobic aquatic test organisms cannot be determined in studies when the solubility of the dissolved ferric kation (as the ferrous form will readily be oxidized to ferric species) is exceeded. None of the experiments found effects at such low levels (depend on pH, section “water solubility”). Notwithstanding the methodological objections formally expressed in the waiving argument for the standard aquatic test organisms, the following data are mentioned for completeness.

Freshwater species:

Table: Data from the EURAS critical review (Vangheluwe & Versonnen 2004, table 3, p 11-12 & 15 and table 3, p 17-18)

Test substance	Test organism	Test medium	Test conditions	Nominal / Measured	Duration	Endpoints	NOEC [mg/L]	LOEC [mg/L]	L(E)C50 [mg/L]	Reference	Author’s Reliability
FeSO4.7H2O	Oncorhynchus mykiss	Dechlorinated / carbon filtered tap water	pH: 6.0-7.1; H: 56-60; Alk: 32, a	TD, c	96 h	Survival			16.6	Mattock 2002a	R1
Fe2(SO4)3	Oncorhynchus mykiss	Dechlorinated / carbon filtered tap water	pH: 6.9-7.0; T: 13-15; H: 64-97	TD, c	96 h	Survival			pH adjusted: >27.9	Mattock 2002b	R1
FeCl3.6H2O	Pimephales promelas	Reconstituted ASTM water	pH: 6.7; T: 22; H: 100; Alk: 30	To	96 h	Survival			21.8 (measured To)	Birge et al. 1985	R1
	Lepomis macrochirus		pH: 6.3; T: 22: H: 100; Alk: 24	To	96 h	Survival			20.3 (measured To)
FeSO4	Salvelinus fontinalis	Carbon filtered river water	pH: 5.5	To, TD	96 h	Survival			0.41 (measured dissolved)	Decker & Menendez 1974	R2
			pH: 6						0.48 (measured dissolved)
			pH: 7						1.75 (measured dissolved)
FeSO4	Cyprinus carpio	Not reported	pH: 7.1; small carp	N	96 h	Survival			0.83	Alam & Maugham 1992	R2
			pH: 7.1; larger carp						1.62
FeCl3.6H2O	Danio rerio	Aerated, aged tap water	pH: 5; T: 25; H: 40	N	48 h	Survival		>32		Dave 1985	R2
			pH: 7; T: 25; H: 40		48 h			>32
			pH: 9; T: 25; H: 40		48 h			>32
NON-STANDARD SPECIES
FeSO4.7H2O	Lampetra fluviatilis(Lamprey)	Groundwater	pH: 6; T: 20	N	72 h	Hatching	0.5		EC50: 1.1	Myllynen et al. 1997	R1
		River water	pH: 5; T: 20			Survival	2		LC50: 3.4		R1

a: only measured prior to testing

Alk: alkalinity [mg/L CaCO3]

c: samples were filtered over a 0.2 µm filter

H: hardness [mg/L CaCO3]

N: Nominal concentration

R1: Reliable without restriction according to the scheme of the authors (set out in chapter 3.2 of their publication), corrected to Klimisch 3 “not reliable” as discussed above.

R2: Reliable with restrictions according to the authors (set out in chapter 3.2 of their publication), corrected to Klimisch 3 “not reliable” as discussed above.

T: temperature [°C]

TD: dissolved total Fe measured

To: total Fe measured

Table: Data according to Johnson et al. (2007, table 2.7, p 24)

Scientific name	Common name	Endpoint	Effect	Test duration [h]	Concentration [mg/L] #	Exposure	Toxicant analysis	Comments (Author's Reliability)	Reference
Brachydanio rerio	Zebrafish (larvae)	NOEC	Mortality	48	32	s	n	As FeCl3 (R3)	Dave 1985
Cyprinus carpio	Carp 3.2 cm fry	LC50	Mortality	96	0.96	ss	n	As FeSO4; pH 7.1 (R3)	Alam & Maughan 1992
Cyprinus carpio	Carp, 6.9 cm fry	LC50	Mortality	96	1.74	ss	n	As FeSO4; pH 7.1 (R3)	Alam & Maughan 1992
Oncorhynchus mykiss	Rainbow trout juveniles	LC50	Mortality	96	2.9	f	y	As Fe2(SO4)3; pH 7.2–7.5	Mance & Campbell 1988
Oryzias latipes	Medaka (8 day fry)	LC50	Mortality	24	1.0–10	s	n	As NH4Fe(SO4)2; pH 6.9 (R3)	Hiraoka et al 1985
Salmo trutta	Brown trout juveniles	LC50	Mortality	96	8.5	f	y	As Fe2(SO4)3; pH 7.2–7.5	Mance & Campbell 1988
Salvelinus fontinalis	Brook trout 14 months old	LC50	Mortality	96	0.41 (d)	f	y	As FeSO4; pH 5.5 (R2)	Decker & Menendez 1974
Salvelinus fontinalis	Brook trout 14 months old	LC50	Mortality	96	0.48 (d)	f	y	As FeSO4; pH 6.0 (R2)	Decker & Menendez 1974
Salvelinus fontinalis	Brook trout 14 months old	LC50	Mortality	96	1.75 (d)	f	y	As FeSO4; pH 7.2 (R2)	Decker & Menendez 1974

# Concentration related to iron if not stated otherwise under comments (third-to-last column)

R2: Reliable with restrictions according to the authors (set out in Annex 1, p 56 of their publication), corrected to Klimisch 3 “not reliable” as discussed above.

R3: Not reliable according to the authors (set out in Annex 1, p 56 of their publication)

d = dissolved.

Exposure: s = static; ss = semi-static; f = flow-through.

Toxicant analysis: y = measured; n = not measured.

Table: Data from the OECD (2007) assessment (table 28, p 65)

Test substance	Test organism	Test duration	Effect	LC50 [mg Fe/L]	Reference	Author’s Reliability
FeCl3.6H2O	Lepomis macrochirus	96 h	Survival at pH 4.8-7.8	20 (m.t)	Birge et al. (1985)	R2
Fe2(SO4)3	Oncorhynchus mykiss	96 h	Survival at pH 6.9-7.4	>28 (n.t)	Mattock (2002a)	R1
			Survival at pH 4.1-7.1	13 (n.t)
FeSO4	Salvelinus fontinalis	96 h	Survival at pH 5.5	0.41 (m.d)	Decker & Menendez (1974)	R2
			Survival at pH 6.0	0.48 (m.d)
			Survival at pH 7.0	1.8 (m.d)
FeSO4	Cyprinus carpio	96 h	Survival at pH 7.1	0.83 (n.t)	Alam & Maugham 1992	R2
FeSO4.7H2O	Oncorhynchus mykiss	96 h	Survival at pH 6.0 -7.1	17 (n.t), 1.7 (m.t)	Mattock (2002b)	R1

m.t = measured total Fe

m.d = measured dissolved Fe

n.t = nominal total Fe

R1, R2 = Rating by the authors (OECD 2007) referring to the Klimisch et al. (1997) scale, corrected to Klimisch 3 “not reliable” as discussed above.

Saltwater species:

Table: Data from the EURAS critical review (Vangheluwe & Versonnen 2004, table 4, p 18)

Test substance	Test organism	Test medium	Test conditions	Nominal / Measured	Duration	Endpoints	LC50 [mg/L]	Reference	Reliability
FeSO4.7H2O	Theraon humeralis	Filtered seawater	pH:8.1; S: 35; T: 20 °C	N, a	24 h	Survival	LC50: 16.7	Francesconi & Edmonds 1995	R2
			pH: 8.1; S: 35; T: 25°C				LC50: 11.8

a: only measured prior to testing

N: Nominal concentration

R2: Reliable with restrictions according to the authors (set out in chapter 3.2 of their publication), corrected to Klimisch 3 “not reliable” as discussed above

S: Salinity [g/L]

T: temperature [°C]

Table: Data according to Johnson et al. (2007, table 2.9, p 29)

Scientific name	Common name	Endpoint	Effect	Test duration [h]	Concentration [mg /L] #	Exposure	Toxicant analysis	Comments (Author's Reliability)	Reference
Morone saxatiis	Striped bass	LC50	Mortality	96	13.6	static	not measured	As FeCl2 (R3)	Hughes 1973

# Concentration related to iron if not stated otherwise under comments (third-to-last column)

R3: Not reliable according to the authors (set out in Annex 1, p 56 of their publication)

Table: Data from the OECD (2007) assessment (table 24, p 67)

Test substance	Test organism	Test duration	Effect	Endpoint [mg Fe/L]	Reference	Author’s Reliability
FeSO4.7H2O	Therapon humeralis, sea trumpeter	24 h	Survival at pH 8.1	12 (nominal total)	Francesconi & Edmonds 1995	R2

R2 = Rating by the authors (OECD 2007) referring to the Klimisch et al. (1997) scale, corrected to Klimisch 3 “not reliable” as discussed above.

• Alam MK, Maugham OE (1992). The effect of malathion, diazinon and various concentrations of zinc, copper, nickel, lead, iron and mercury on fish. DOI 10.1007/BF02783678 PMID 1384613 Biological Trace Element Research 34(3):225-36.
• Birge WJ, Black JA, Westerman AG, Short TM, Taylor SB, Bruser DM, Wallingford ED (1985). Recommendations on numerical values for regulating iron and chloride concentrations for the purpose of protecting warmwater species of aquatic life in the Commonwealth of Kentucky. Memorandum of Agreement No. 5429, Kentucky Natural Resources and Environmental Protection Cabinet.
• Dave G (1985). The influence of pH on the toxicity of aluminium, cadmium, and iron to eggs and larvae of the zebrafish, Brachydanio rerio. Ecotoxicology and Environmental Safety 10:253–67.
• Decker C, Menendez R (1974). Acute toxicity of iron and aluminium to brook trout. Proceedings of the West Virginia Academy of Science 46:159–67.
• Francesconi KA,Edmonds JS (1995). Short-term effects on sea trumpeter (Therapon humeralis) of oxidizing iron (II) in seawater. Bulletin of Environmental Contamination and Toxicology 54:15-21.
• Hiraoka Y, Ishizawa S, Kamada T, Okuda H (1985) Acute toxicity of 14 different kinds of metals affecting Medaka fry. Hiroshima Journal of Medical Sciences 34:327–30.
• Hughes JS (1973). Acute toxicity of thirty chemicals to striped bass (Morone saxatilis). Louisiana Department of Wildlife and Fish Report 318-343-2417. Baton Rouge, LA: Louisiana Department of Wildlife and Fish.
• Johnson I, Sorokin N, Atkinson C, Rule K, Hope S-J (2007). Proposed EQS for Water Framework Directive Annex VIII substances: iron (total dissolved). ISBN: 978-1-84432-660-0. Science Report: SC040038/SR9. SNIFFER Report: WFD52(ix). Product Code SCHO0407BLWB-E-E. Self-published by Environment Agency, Almondsbury, Bristol BS32 4UD, U.K. 65 p.
• Klimisch H-J, Andreae M, Tillmann U (1997). A systematic approach for evaluating the quality of experimental toxicological and ecotoxicological data. Regul Toxicol Pharm 25:1-7.
• Mance G, Campbell JA (1988). Proposed Environmental Quality Standards for List II substances in water: iron. Technical Report TR258. Medmenham, Buckinghamshire: WRc.
• Mattock S (2002a). Iron sulphate heptahydrate: acute toxicity to Oncorhynchus mykiss. Covance report number 1934/1 D2149.
• Mattock S (2002b). Diiron tris (sulphate): Acute toxicity to Oncorhynchus mykiss. Covance report number 1934/2 D2149.
• Myllynen K, Ojutkangas E, NIkinmaa M (1997). River water with high iron concentration and low pH causes mortality of Lamprey Roe and newly hatched larvae. Ecotoxicology and Environmental Safety 36:43-8.$
• OECD Organisation for Economic Co-operation and Development (2007). SIDS Initial Assessment Report for SIAM 24. Chemical Category: Iron Salts. Self-published, Paris, France, 17-20 April. 138 p.
• Vangheluwe M, Versonnen B (2004). Critical review on acute and chronic aquatic ecotoxicity data to be used for classification purposes of iron sulfate. Commissioned by ARCELOR SA, CEFIC, EUROFER, Rio Tinto plc. Final report - 25 August 2004. Prepared by EURAS, Rijvisschestraat 118, box 3. B-9052 Gent, Belgium. 76 p.