[No public or meaningful name is available]

Toxicity to aquatic algae and cyanobacteria

Administrative data

Endpoint:

toxicity to aquatic algae and cyanobacteria

Data waiving:

study scientifically not necessary / other information available

Justification for data waiving:

other:

Justification for type of information:

JUSTIFICATION FOR DATA WAIVING
According to Annex VII, Column 2, Section 9.1.2. of Regulation (EC) 1907/2006, the test for growth inhibition of aquatic plants does not need to be conducted “if there are mitigating factors indicating that aquatic toxicity is unlikely to occur, for instance if the substance is highly insoluble in water or the substance is unlikely to cross biological membranes”.

Chromium, iron, titanium and zinc spinel and rutile can be considered environmentally and biologically inert due to the characteristics of the synthetic process (calcination at a high temperature of approximately 1000°C), rendering the substance to be of a unique, stable crystalline structure in which all atoms are tightly bound and not prone to dissolution in environmental and physiological media. This assumption is supported by transformation/dissolution data (Knopf, 2018) that indicate a very low release of pigment components at pH 6 and 8. Transformation/dissolution tests with chromium, iron, titanium and zinc spinel and rutile at a loading of 1 mg/L and pH 6 after 7 days resulted in dissolved chromium concentrations of 0.229 µg Cr/L, iron and titanium concentrations below the respective LODs of 0.035 µg Fe/L and 0.041 µg Ti/L, and zinc concentrations of 0.929 µg Zn/L. After 28 days at pH 6 dissolved chromium, iron and zinc concentrations amounted to 0.355 µg Cr/L, 0.532 µg Fe/L and 3.52 µg Zn/L, respectively, while titanium concentrations remained below the LOQ of 0.123 µg Ti/L. T/D tests at pH 8 after 7 days resulted in dissolved chromium and zinc concentrations of 0.2 µg Cr/L and 3.68 µg Zn/L, while iron and titanium concentrations remained below the LOD of 0.085 µg Fe/L and 0.123 µg Ti/L, respectively. After 28 days at pH 8 dissolved chromium, iron, titanium and zinc concentrations amounted to 0.314 µg Cr/L, 0.136 µg Fe/L, 0.022 µg Ti/L and 4.78 µg Zn/L, respectively. Thus, the rate and extent to which chromium, iron, titanium and zinc spinel and rutile produces soluble (bio)available ionic and other chromium-, iron-, titanium-, and zinc-bearing species in environmental media is limited. Hence, the pigment can be considered as environmentally and biologically inert during short- and long-term exposure. The poor solubility of chromium, iron, titanium and zinc spinel and rutile is expected to determine its behaviour and fate in the environment, and subsequently its potential for ecotoxicity.

Proprietary studies are not available for chromium, iron, titanium and zinc spinel and rutile. The poorly soluble substance chromium, iron, titanium and zinc spinel and rutile is evaluated by comparing the dissolved metal ion levels resulting from the transformation/dissolution test after 7 and 28 days at a loading rate of 1 mg/L with the lowest acute and chronic ecotoxicity reference values (ERVs) as determined for the (soluble) metal ions. The acute and chronic ERVs are based on the lowest EC50/LC50 or NOEC/EC10 values for algae, invertebrates and fish, respectively, and were obtained from the Metals classification tool (MeClas) database as follows:
The acute ERVs of trivalent chromium (> 100 mg Cr/L), iron (> 100 mg Fe/L) and titanium are above 1 mg/L and thus a concern for short-term (acute) toxicity was not identified (no classification). According to ECHA Guidance on the Application of the CLP Criteria (Version 5.0, July 2017), “Where the acute ERV for the metal ions of concern is greater than 1 mg/L the metals need not be considered further in the classification scheme for acute hazard.” The acute ERVs for zinc are 413 µg Zn/L at pH 6-7 and 136 µg Zn/L at pH >7 and thus well above the respective dissolved zinc concentrations of 0.929 µg Zn/L at pH 6 and 3.68 µg Zn/L at pH 8 obtained after 7 days T/D tests at a loading of 1 mg/L. Due to the lack of an acute aquatic hazard potential for soluble trivalent chromium, iron and titanium ions and the fact that dissolved zinc concentrations after 7 days T/D tests at a loading of 1 mg/L and pH 6 and 8 remained well below the respective lowest acute ERVs, it can be concluded that the substance chromium, iron, titanium and zinc spinel and rutile is not sufficiently soluble to cause short-term toxicity at the level of the acute ERVs (expressed as EC50/LC50).
Regarding the long-term toxicity, the chronic ERVs for trivalent chromium, iron and titanium, are above 1 mg/L and a concern for long-term (chronic) toxicity was not identified (no classification). According to ECHA Guidance on the Application of the CLP Criteria (Version 5.0, July 2017), ”Where the chronic ERV for the metal ions of concern corrected for the molecular weight of the compound (further called as chronic ERV compound) is greater than 1 mg/L, the metal compounds need not to be considered further in the classification scheme for long-term hazard.” The chronic ERVs for zinc are 82 µg Zn/L at pH 6-7 and 19 µg Zn/L at pH >7 and thus well above the respective dissolved zinc concentrations of 3.52 µg Zn/L at pH 6 and 4.78 µg Zn/L at pH 8 determined after 28 days T/D tests at a loading of 1 mg/L. Due to the lack of a chronic aquatic hazard potential of chromium, iron and titanium and the fact that dissolved zinc concentrations after 28 days T/D tests at a loading of 1 mg/L and pH 6 and 8 remained well below the respective lowest chronic ERVs, it can be concluded that the substance chromium, iron, titanium and zinc spinel and rutile is not sufficiently soluble to cause long-term toxicity at the level of the chronic ERVs (expressed as NOEC/EC10).

In accordance with Figure IV.4 “Classification strategy for determining acute aquatic hazard for metal compounds” and Figure IV.5 „Classification strategy for determining long-term aquatic hazard for metal compounds “of ECHA Guidance on the Application of the CLP Criteria (Version 5.0, July 2017) and section 4.1.2.10.2. of Regulation (EC) No 1272/2008, the substance chromium, iron, titanium and zinc spinel and rutile is poorly soluble and does not meet classification criteria for acute (short-term) and chronic (long-term) aquatic hazard.

Chromium, iron, titanium and zinc spinel and rutile is poorly soluble and unlikely to cross biological membranes. In accordance with Annex VII, Column 2, Section 9.1.2. of Regulation (EC) 1907/2006, testing for growth inhibition of aquatic plants is not necessary.

Cross-reference

Reason / purpose for cross-reference:

data waiving: supporting information

Reference

Endpoint:

transformation / dissolution of metals and inorganic metal compounds

Type of information:

experimental study

Adequacy of study:

key study

Study period:

2017-08-07 to 2017-10-20

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Qualifier:

according to guideline

Guideline:

OECD Series on Testing and Assessment No. 29 (23-Jul-2001): Guidance document on transformation/dissolution of metals and metal compounds in aqueous media

Deviations:

no

GLP compliance:

yes (incl. QA statement)

Remarks:

signed 2016-05-31

Type of method:

flask method

Key result

Type of test:

full transformation/dissolution test - metals and sparingly soluble metal compounds

Mean dissolved conc.:

0.355 µg/L

Element analysed:

Cr

Loading of aqueous phase:

1 mg/L

Incubation duration:

28 d

Test conditions:

pH = 6, separation of solid phase by filtration 0.2 µm

Key result

Type of test:

full transformation/dissolution test - metals and sparingly soluble metal compounds

Mean dissolved conc.:

0.314 µg/L

Element analysed:

Cr

Loading of aqueous phase:

1 mg/L

Incubation duration:

28 d

Test conditions:

pH = 8, separation of solid phase by filtration 0.2 µm

Key result

Type of test:

full transformation/dissolution test - metals and sparingly soluble metal compounds

Mean dissolved conc.:

4.42 µg/L

Element analysed:

Cr

Loading of aqueous phase:

100 mg/L

Incubation duration:

7 d

Test conditions:

pH = 8, separation of solid phase by filtration 0.2 µm

Key result

Type of test:

full transformation/dissolution test - metals and sparingly soluble metal compounds

Mean dissolved conc.:

0.229 µg/L

Element analysed:

Cr

Loading of aqueous phase:

1 mg/L

Incubation duration:

7 d

Test conditions:

pH = 6, separation of solid phase by filtration 0.2 µm

Key result

Type of test:

full transformation/dissolution test - metals and sparingly soluble metal compounds

Mean dissolved conc.:

0.2 µg/L

Element analysed:

Cr

Loading of aqueous phase:

1 mg/L

Incubation duration:

7 d

Test conditions:

pH = 8, separation of solid phase by filtration 0.2 µm

Type of test:

full transformation/dissolution test - metals and sparingly soluble metal compounds

Mean dissolved conc.:

4.17 µg/L

Element analysed:

Cr

Loading of aqueous phase:

100 mg/L

Incubation duration:

24 h

Test conditions:

pH = 8, separation of solid phase by filtration 0.2 µm

Type of test:

full transformation/dissolution test - metals and sparingly soluble metal compounds

Mean dissolved conc.:

0.079 µg/L

Element analysed:

Cr

Loading of aqueous phase:

1 mg/L

Incubation duration:

24 h

Test conditions:

pH = 6, separation of solid phase by filtration 0.2 µm

Type of test:

full transformation/dissolution test - metals and sparingly soluble metal compounds

Mean dissolved conc.:

0.111 µg/L

Element analysed:

Cr

Loading of aqueous phase:

1 mg/L

Incubation duration:

24 h

Test conditions:

pH = 8, separation of solid phase by filtration 0.2 µm

Key result

Type of test:

full transformation/dissolution test - metals and sparingly soluble metal compounds

Mean dissolved conc.:

0.532 µg/L

Element analysed:

Fe

Loading of aqueous phase:

1 mg/L

Incubation duration:

28 d

Test conditions:

pH = 6, separation of solid phase by filtration 0.2 µm

Key result

Type of test:

full transformation/dissolution test - metals and sparingly soluble metal compounds

Mean dissolved conc.:

0.136 µg/L

Element analysed:

Fe

Loading of aqueous phase:

1 mg/L

Incubation duration:

28 d

Test conditions:

pH = 8, separation of solid phase by filtration 0.2 µm

Key result

Type of test:

full transformation/dissolution test - metals and sparingly soluble metal compounds

Mean dissolved conc.:

< 0.463 µg/L

Element analysed:

Fe

Loading of aqueous phase:

100 mg/L

Incubation duration:

7 d

Test conditions:

pH = 8, separation of solid phase by filtration 0.2 µm

Remarks on result:

other:

Remarks:

conc. of all replicates < LOD: 0.463 µg/L

Key result

Type of test:

full transformation/dissolution test - metals and sparingly soluble metal compounds

Mean dissolved conc.:

< 0.035 µg/L

Element analysed:

Fe

Loading of aqueous phase:

1 mg/L

Incubation duration:

7 d

Test conditions:

pH = 6, separation of solid phase by filtration 0.2 µm

Remarks on result:

other:

Remarks:

conc. of all replicates < LOD: 0.035 µg/L

Key result

Type of test:

full transformation/dissolution test - metals and sparingly soluble metal compounds

Mean dissolved conc.:

< 0.085 µg/L

Element analysed:

Fe

Loading of aqueous phase:

1 mg/L

Incubation duration:

7 d

Test conditions:

pH = 8, separation of solid phase by filtration 0.2 µm

Remarks on result:

other:

Remarks:

conc. of all replicates < LOD: 0.085 µg/L

Type of test:

full transformation/dissolution test - metals and sparingly soluble metal compounds

Mean dissolved conc.:

< 0.463 µg/L

Element analysed:

Fe

Loading of aqueous phase:

100 mg/L

Incubation duration:

24 h

Test conditions:

pH = 8, separation of solid phase by filtration 0.2 µm

Remarks on result:

other:

Remarks:

conc. of all replicates < LOD: 0.463 µg/L

Type of test:

full transformation/dissolution test - metals and sparingly soluble metal compounds

Mean dissolved conc.:

0.123 µg/L

Element analysed:

Fe

Loading of aqueous phase:

1 mg/L

Incubation duration:

24 h

Test conditions:

pH = 6, separation of solid phase by filtration 0.2 µm

Type of test:

full transformation/dissolution test - metals and sparingly soluble metal compounds

Mean dissolved conc.:

0.273 µg/L

Element analysed:

Fe

Loading of aqueous phase:

1 mg/L

Incubation duration:

24 h

Test conditions:

pH = 8, separation of solid phase by filtration 0.2 µm

Key result

Type of test:

full transformation/dissolution test - metals and sparingly soluble metal compounds

Mean dissolved conc.:

< 0.123 µg/L

Element analysed:

Ti

Loading of aqueous phase:

1 mg/L

Incubation duration:

28 d

Test conditions:

pH = 6, separation of solid phase by filtration 0.2 µm

Remarks on result:

other:

Remarks:

conc. of all replicates < LOD / LOQ: 0.041 µg/L / 0.123 µg/L

Key result

Type of test:

full transformation/dissolution test - metals and sparingly soluble metal compounds

Mean dissolved conc.:

0.022 µg/L

Element analysed:

Ti

Loading of aqueous phase:

1 mg/L

Incubation duration:

28 d

Test conditions:

pH = 8, separation of solid phase by filtration 0.2 µm

Key result

Type of test:

full transformation/dissolution test - metals and sparingly soluble metal compounds

Mean dissolved conc.:

< 0.042 µg/L

Element analysed:

Ti

Loading of aqueous phase:

100 mg/L

Incubation duration:

7 d

Test conditions:

pH = 8, separation of solid phase by filtration 0.2 µm

Remarks on result:

not determinable

Remarks:

not distinguishable from blank

Key result

Type of test:

full transformation/dissolution test - metals and sparingly soluble metal compounds

Mean dissolved conc.:

< 0.041 µg/L

Element analysed:

Ti

Loading of aqueous phase:

1 mg/L

Incubation duration:

7 d

Test conditions:

pH = 6, separation of solid phase by filtration 0.2 µm

Remarks on result:

other:

Remarks:

conc. of all replicates at least < LOD: 0.041 µg/L

Key result

Type of test:

full transformation/dissolution test - metals and sparingly soluble metal compounds

Mean dissolved conc.:

< 0.123 µg/L

Element analysed:

Ti

Loading of aqueous phase:

1 mg/L

Incubation duration:

7 d

Test conditions:

pH = 8, separation of solid phase by filtration 0.2 µm

Remarks on result:

other:

Remarks:

conc. of all replicates at least < LOQ: 0.123 µg/L

Type of test:

full transformation/dissolution test - metals and sparingly soluble metal compounds

Mean dissolved conc.:

< 0.042 µg/L

Element analysed:

Ti

Loading of aqueous phase:

100 mg/L

Incubation duration:

24 h

Test conditions:

pH = 8, separation of solid phase by filtration 0.2 µm

Remarks on result:

not determinable

Remarks:

not distinguishable from blank

Type of test:

full transformation/dissolution test - metals and sparingly soluble metal compounds

Mean dissolved conc.:

< 0.123 µg/L

Element analysed:

Ti

Loading of aqueous phase:

1 mg/L

Incubation duration:

24 h

Test conditions:

pH = 6, separation of solid phase by filtration 0.2 µm

Remarks on result:

other:

Remarks:

conc. of all replicates at least < LOQ: 0.123 µg/L

Type of test:

full transformation/dissolution test - metals and sparingly soluble metal compounds

Mean dissolved conc.:

< 0.123 µg/L

Element analysed:

Ti

Loading of aqueous phase:

1 mg/L

Incubation duration:

24 h

Test conditions:

pH = 8, separation of solid phase by filtration 0.2 µm

Remarks on result:

other:

Remarks:

conc. of all replicates at least < LOQ: 0.123 µg/L

Key result

Type of test:

full transformation/dissolution test - metals and sparingly soluble metal compounds

Mean dissolved conc.:

3.52 µg/L

Element analysed:

Zn

Loading of aqueous phase:

1 mg/L

Incubation duration:

28 d

Test conditions:

pH = 6, separation of solid phase by filtration 0.2 µm

Key result

Type of test:

full transformation/dissolution test - metals and sparingly soluble metal compounds

Mean dissolved conc.:

4.78 µg/L

Element analysed:

Zn

Loading of aqueous phase:

1 mg/L

Incubation duration:

28 d

Test conditions:

pH = 8, separation of solid phase by filtration 0.2 µm

Key result

Type of test:

full transformation/dissolution test - metals and sparingly soluble metal compounds

Mean dissolved conc.:

23.3 µg/L

Element analysed:

Zn

Loading of aqueous phase:

100 mg/L

Incubation duration:

7 d

Test conditions:

pH = 8, separation of solid phase by filtration 0.2 µm

Key result

Type of test:

full transformation/dissolution test - metals and sparingly soluble metal compounds

Mean dissolved conc.:

0.929 µg/L

Element analysed:

Zn

Loading of aqueous phase:

1 mg/L

Incubation duration:

7 d

Test conditions:

pH = 6, separation of solid phase by filtration 0.2 µm

Key result

Type of test:

full transformation/dissolution test - metals and sparingly soluble metal compounds

Mean dissolved conc.:

3.68 µg/L

Element analysed:

Zn

Loading of aqueous phase:

1 mg/L

Incubation duration:

7 d

Test conditions:

pH = 8, separation of solid phase by filtration 0.2 µm

Type of test:

full transformation/dissolution test - metals and sparingly soluble metal compounds

Mean dissolved conc.:

20.5 µg/L

Element analysed:

Zn

Loading of aqueous phase:

100 mg/L

Incubation duration:

24 h

Test conditions:

pH = 8, separation of solid phase by filtration 0.2 µm

Type of test:

full transformation/dissolution test - metals and sparingly soluble metal compounds

Mean dissolved conc.:

< 0.052 µg/L

Element analysed:

Zn

Loading of aqueous phase:

1 mg/L

Incubation duration:

24 h

Test conditions:

pH = 6, separation of solid phase by filtration 0.2 µm

Remarks on result:

not determinable

Remarks:

not distinguishable from blank

Type of test:

full transformation/dissolution test - metals and sparingly soluble metal compounds

Mean dissolved conc.:

2.17 µg/L

Element analysed:

Zn

Loading of aqueous phase:

1 mg/L

Incubation duration:

24 h

Test conditions:

pH = 8, separation of solid phase by filtration 0.2 µm

Details on results:

Background correction:
All data presented are corrected for background when possible, i.e., when measured Cr, Fe, Zn or Ti concentrations in blanks >LOQ.

Solution pH, oxygen concentrations, temperature
The temperature of the thermostatically controlled room was recorded with a data logger. The mean temperature was 21.3 ± 0.3 °C and 21.2 ± 0.3 °C for the additional test with 100 mg loading pH=8. The solution pH remained relatively constant for the pH 6 treatment for the method blank vessels (6.15 – 6.37) as for the sample vessels (5.83 – 6.37).
Oxygen levels in all test vessels pH 6 were in the range recommended by the OECD Test Guidance 29 during the test: above 70 % of oxygen saturation at 8.5 mg/L (70 % of 8.5 mg/L = 6 mg/L). The solution pH of the pH 8 remained relatively constant during the test in the method blanks (7.83 – 7.98) as well as in the sample vessels (7.78 – 7.97) for both the 1 mg loading and the 100 mg loading experiment. Oxygen levels in all test vessels pH 8 were in the range recommended by the OECD Test Guidance 29 during the test: above 70 % of oxygen saturation at 8.5 mg/L (70 % of 8.5 mg/L = 6 mg/L).

Analytical measurements: Within and between vessel variations of elemental concentrations (Cr, Fe, Zn, Ti)
Within and between vessel variations are not always in compliance with the guidance for the tests. The particle size distribution of each loading replicate may differ and thus resulting in different overall total surface areas per vessel. For these samples the observed variations of > 20 % (between-vessel) or > 10 % (within-vessel) were mainly in the recommended range for Cr and Zn pH 6. For iron (both pHs), Ti (both pHs) and Zn (pH 8, mainly only the between-vessel variation) variations were not in the recommended range, probably due to the low dissolution and the majority of measurements being close to – or below – the respective quantification limit of the method.

Method validation summary (ICP-OES)

Limits of detection (LODs), limits of quantification (LOQs) and correlation coefficients (r)

Limits of detection (LOD) within all measurement series: 0.049 -0.052 μg Zn / L, 0.035 - 0.085 µg / L Fe

Limit of detection (LOD) for measurements of 100 mg/L loading test: 0.215 µg Zn / L, 0.463 µg Fe / L

Limits of quantification (LOQ) within all measurement series: 0.148 - 0.156 μg Zn / L, 0.106 - 0.255 µg / L Fe

Limit of quantification (LOQ) for measurements of 100 mg/L loading test: 0.645 μg Zn / L, 1.39 µg / L Fe

Correlation coefficients (r) within all measurement series: > 0.999865 (Zn calibration), > 0.999868 (Fe calibration)

Mean recovery of fortified samples (concentration range 25 - 300 µg, n = 8): 97.1 - 106 % (Fe fortification), 102 - 109 % (Zn fortification)

Mean recovery for certified reference material TMDA-52.4 (lot no. 0615, Environment Canada): 99.5 - 103 % (Fe measurement, n = 14), 101 - 104 % (Zn measurement, n = 14)

date	Chosen wavelength [nm]	LOD [µg/L]	LOQ [µg/L]	correlation coefficient	Sum of quality assurance samples	Recovery of quality assurance samples [%]
August 17, 2017; measurement of test samples (24 h and 7 d) and method blank samples (24 h and 7 d) – only pH 6	Fe: 238.204* Zn: 213.857*	Fe: 0.035 Zn: 0.052	Fe: 0.106 Zn: 0.155	Fe: 0.999868 Zn: 0.999865	Fe: 17 Zn:17	Fe: 88.2 Zn: 88.2

date	Chosen wavelength [nm]	LOD [µg/L]	LOQ [µg/L]	correlation coefficient	Sum of quality assurance samples	Recovery of quality assurance samples [%]
September 29, 2017; measurement of test samples (28 d) and method blank samples (28 d) pH 6; pH 8 all test samples and method blank samples(24 h, 7d and 28 d)	Fe: 238.204* Zn: 213.857*	Fe: 0.085 Zn: 0.049	Fe: 0.255 Zn: 0.148	Fe: 0.999940 Zn: 0.999960	Fe: 28 Zn: 28	Fe: 92.9 Zn: 85.7

Method validation summary (ICP-MS)

Limits of detection (LODs), limits of quantification (LOQs)and correlation coefficients (r)

Limits of detection (LOD) within all measurement series: 0.008 - 0.041 μg Ti / L ; 0.005 - 0.006 µg Cr / L

Limit of detection (LOD) for measurements of 100 mg/L loading test: 0.042 µg Ti / L, 0.003 µg Cr / L

Limits of quantification (LOQ) within all measurement series: 0.023 - 0.123 μg Ti / L; 0.016 - 0.018 µg Cr / L

Limit of quantification (LOQ) for measurements of 100 mg/L loading test: 0.126 μg Ti / L, 0.01 µg / L Cr

Correlation coefficients (r) within all measurement series: > 0.9988

Mean recovery of fortified samples (n = 4): 97.4 - 103 % (Cr), 99.1 - 106 % (Ti)

Mean recovery of certified reference material TMDA-52.4 (lot no. 0615, Environment Canada): 105 - 106 % (n=11, Ti), 103 -105 % (n=11, Cr)

Mean recovery of certified reference material TM-26.4 (lot no. 1115, Environment Canada) for measurements of 100 mg/L loading test: 94.4 % (n=4, Ti), 111 % (n=4, Cr)

date	Chosen isotope and gas mode	LOD [µg/L]	LOQ [µg/L]	correlation coefficient	Sum of quality assurance samples	Recovery of quality assurance samples [%]
September 12, 2017; measurement of test samples (all sampling times) and method blank samples (all sampling times) – only pH 6; pH 8 only sampling points 24 h and 7 d	Cr:^52Cr* [Helium gas mode] Ti:^47Ti* [Helium gas mode]	Cr: 0.005 Ti: 0.041	Cr: 0.016 Ti: 0.123	Cr: 0.9996 Ti: 0.9997	Cr: 47 Ti: 47	Cr: 97.9 Ti: 97.9

date	Chosen isotope and gas mode	LOD [µg/L]	LOQ [µg/L]	correlation coefficient	Sum of quality assurance samples	Recovery of quality assurance samples [%]
September 29, 2017; measurement of test samples (28 d) and method blank samples (28 d) – only pH 8	Cr:^52Cr* [HiHelium gas mode] Ti:^47Ti [HiHelium gas mode]	Cr: 0.006 Ti: 0.008	Cr: 0.018 Ti: 0.023	Cr: 0.9988 Ti: 0.9988	Cr: 7 Ti: 7	Cr: 100 Ti: 100

Conclusions:

The transformation/dissolution test (OECD Series on Testing and Assessment Number 29, 2001) of inorganic pigment "Chromium, iron, titanium and zinc spinel and rutile" at a loading of 1 mg/L at pH 6 and 8, performed for 28d, resulted in maximum quantified Cr concentrations of 0.355 µg/L (pH = 6, 28d), maximum Fe concentrations of 0.532 µg/L (pH = 6, 28d), maximum Zn concentrations of 4.78 µg/L (pH = 8, 28d) as well as maximum Ti concentrations of 0.022 µg/L (background corrected, pH = 8, 28d). Thus, the extent to which "Chromium, iron, titanium and zinc spinel and rutile" can produce soluble available ionic and other metal-bearing species in aqueous media is limited. An additional test at pH 8 with 100 mg/L loading for 7 days revealed maximum soluble concentrations of 4.42 µg/L Cr, 23.3 µg/L Zn, < 0.463 µg/L Fe and < 0.042 µg/L Ti.