Administrative data
Link to relevant study record(s)
- Endpoint:
- biodegradation in water: screening tests
- Type of information:
- read-across from supporting substance (structural analogue or surrogate)
- Adequacy of study:
- supporting study
- Reliability:
- 3 (not reliable)
- Rationale for reliability incl. deficiencies:
- other: Method not validated
- Justification for type of information:
- see read across justification in section 13
- Reason / purpose for cross-reference:
- read-across source
- Details on results:
- Reactive Black 5 (vinyl sulfone form): Abnahme der Farbintensität von 1967 ADMI zu 770 ADMI
innerhalb eines Tages. Nach 15 Tagen betrug die
Farbintensität des Filtrats noch ca. 150 ABMI-Einheiten. Die Abnahme innerhalb der ersten 24 Stunden beruht auf die
starke Sorption. Reactiv Black 5 (hydrolyzed): Geringe bzw. keine Änderung der Farbintesität innerhalb von
9 Tagen. Es konnte weder eine Sorption noch ein Bioabbau
festgestellt werden.
- Executive summary:
Batch sludge digestion studies were
conducted under aerobic and anaerobic
conditions to study: (i) the role of
vinyl sulfone and hydroxyl functional
groups in the removal of Reactive Black
5 dye; and (ii) the effect of biomass
concentration on the removal of Navy 106
(mixture of three azo dyes) from a
textile mill wash water. Removals of
color and organic content under aerobic
and anaerobic conditions were compared.
The potential of the dyes to leach from
sludge in landfills was also
investigated using the toxicity
characteristic leaching procedure (TCLP).
The vinyl sulfone group of the Reactive
Black 5 dye enabled the dye to be
removed better than the hydrolyzed form
of the dye under aerobic conditions.
Sorption and aerobic color degradation
of Navy 106 wash water increased with
increased biomass concentration in the
reactors. An inhibition to color removal
from dye wash water under aerobic
conditions was detected at high
color-to-biomass ratios. The inhibition
was accompanied by a lower rate of
nitrate and sulfate release. The total
organic carbon (TOC) and chemical oxygen
demand (COD) of hydrolyzed Reactive
Black 5 dye and Navy 106 wash water
decreased under aerobic conditions.
Under anaerobic conditions, the color
degraded within a day, but the TOC and
COD of the pure dye and wash water did
not decrease. TCLP extracts contained
little, if any, of the dye added to the
suspended growth reactors.
- Endpoint:
- biodegradation in water: ready biodegradability
- Type of information:
- read-across from supporting substance (structural analogue or surrogate)
- Adequacy of study:
- key study
- Justification for type of information:
- see read across justification in section 13
- Reason / purpose for cross-reference:
- read-across source
- Value:
- 81
- Sampling time:
- 42 d
- Remarks on result:
- other: Decolorization
- Details on results:
- The % decolourisation reported is the average of results from the seven participating laboratories. The and range is 72% to 100% decolorization
- Results with reference substance:
- Direct Red 7: 92% decolorization (89% - 100%)
81% decoloration at 580 nm; sludge concentration: 200 mg/L
- Validity criteria fulfilled:
- yes
- Conclusions:
- 81% decolorization of Reactive Black 5
- Executive summary:
The paper describes a method for
measuring the primary biodegradability
of water soluble dyestuffs under
anaerobic conditions and gives the
results obtained on 22 dyes of
commercial significance.
- Endpoint:
- biodegradation in water: inherent biodegradability
- Type of information:
- read-across from supporting substance (structural analogue or surrogate)
- Adequacy of study:
- key study
- Justification for type of information:
- see read across justification in section 13
- Reason / purpose for cross-reference:
- read-across source
- Key result
- Parameter:
- % degradation (DOC removal)
- Value:
- 0
- Sampling time:
- 28 d
- Details on results:
- 9 % adsorption after 3 h (DOC- and photometricdetermination at 580 nm)
- Validity criteria fulfilled:
- not specified
- Interpretation of results:
- not inherently biodegradable
- Conclusions:
- not biodegradable, but 60% color elimination after 28 days
- Executive summary:
DOC start [mg/L] |
DOC ads [%] |
DOC elim [%] |
DOC cat |
col ads [%] |
col elim [%] |
col cat |
elim cal |
lambda [nm] |
time [d] |
13 |
9 |
-53 |
D |
9 |
60 |
B |
- |
580 |
28 |
- Endpoint:
- biodegradation in water: ready biodegradability
- Type of information:
- experimental study
- Adequacy of study:
- supporting study
- Reliability:
- 3 (not reliable)
- Rationale for reliability incl. deficiencies:
- other: Method not validated
- Specific details on test material used for the study:
- Details on properties of test surrogate or analogue material (migrated information):
NA - Oxygen conditions:
- aerobic
- Inoculum or test system:
- activated sludge, domestic, non-adapted
- Details on results:
- Reactive Black 5 (vinyl sulfone form): Abnahme der Farbintensität von 1967 ADMI zu 770 ADMI
innerhalb eines Tages. Nach 15 Tagen betrug die
Farbintensität des Filtrats noch ca. 150 ABMI-Einheiten. Die Abnahme innerhalb der ersten 24 Stunden beruht auf die
starke Sorption. Reactiv Black 5 (hydrolyzed): Geringe bzw. keine Änderung der Farbintesität innerhalb von
9 Tagen. Es konnte weder eine Sorption noch ein Bioabbau
festgestellt werden.
- Executive summary:
Batch sludge digestion studies were
conducted under aerobic and anaerobic
conditions to study: (i) the role of
vinyl sulfone and hydroxyl functional
groups in the removal of Reactive Black
5 dye; and (ii) the effect of biomass
concentration on the removal of Navy 106
(mixture of three azo dyes) from a
textile mill wash water. Removals of
color and organic content under aerobic
and anaerobic conditions were compared.
The potential of the dyes to leach from
sludge in landfills was also
investigated using the toxicity
characteristic leaching procedure (TCLP).
The vinyl sulfone group of the Reactive
Black 5 dye enabled the dye to be
removed better than the hydrolyzed form
of the dye under aerobic conditions.
Sorption and aerobic color degradation
of Navy 106 wash water increased with
increased biomass concentration in the
reactors. An inhibition to color removal
from dye wash water under aerobic
conditions was detected at high
color-to-biomass ratios. The inhibition
was accompanied by a lower rate of
nitrate and sulfate release. The total
organic carbon (TOC) and chemical oxygen
demand (COD) of hydrolyzed Reactive
Black 5 dye and Navy 106 wash water
decreased under aerobic conditions.
Under anaerobic conditions, the color
degraded within a day, but the TOC and
COD of the pure dye and wash water did
not decrease. TCLP extracts contained
little, if any, of the dye added to the
suspended growth reactors.
- Endpoint:
- biodegradation in water: ready biodegradability
- Type of information:
- experimental study
- Adequacy of study:
- key study
- Reliability:
- 2 (reliable with restrictions)
- Rationale for reliability incl. deficiencies:
- other: Well documented publication
- Principles of method if other than guideline:
- ETAD Ecological Method No. 105. A screening test for assessing the primary anaerobic biodegradability of
water-soluble dyestuffs
- GLP compliance:
- not specified
- Oxygen conditions:
- anaerobic
- Inoculum or test system:
- activated sludge, non-adapted
- Details on inoculum:
- Preparation of the Anaerobic Sludge Inoculum:
This is obtained either from the digester of a sewage treatment works operating the heated sludge digestion process and treating predominantly domestic waste, or from a laboratory operated digester fed to a specified protocol with activated sludge and yeast extract.
In either case the sludge is kept warm (35 +/- 2°C) in a nearly full, loosely stoppered, container for a maximum of 5 days before use, and the dry sludge solids determined by drying aliquots to constant weight.
Sludge concentration: 200 mg/L
- Duration of test (contact time):
- 42 d
- Initial conc.:
- 100 mg/L
- Based on:
- test mat.
- Parameter followed for biodegradation estimation:
- DOC removal
- Details on study design:
- Apparatus
A set of identical glass bottles of known capacity in the range 0.5 +/- 0.2 litre is required. Each bottle should be fitted with a magnetic stirring bar, be sealed by a valve such that any gases given off may escape, and have a neck of dimensions such that a dissolved oxygen electrode can be introduced. Three such bottles are required for each dye to be tested plus a further three bottles for the dyestuff Direct Red 7 which is used as a positive control. An incubator or waterbath with capacity for the bottles and set at 35 +/- 2°C is also required.
Preparation of the test medium:
The test medium is freshly prepared as follows using inorganic chemicals of analytical quality:
Ammonium sulphate: 0.15 g
Monopotassium phosphate: 0.10 g
Disodium phosphate: 0.90 g
Magnesium sulphate: 0.02 g
Calcium chloride: 0.01 g
Yeast extract: 0.003 g
Glucose: 0.005 g
Casein: 0.003 g
Distilled water: 1 litre
Immediately prior to the test the medium is warmed to 35 +/- 1°C.
- Reference substance:
- other: Direct Red 7
- Value:
- 81
- Sampling time:
- 42 d
- Remarks on result:
- other: Decolorization
- Details on results:
- The % decolourisation reported is the average of results from the seven participating laboratories. The and range is 72% to 100% decolorization
- Results with reference substance:
- Direct Red 7: 92% decolorization (89% - 100%)
81% decoloration at 580 nm; sludge concentration: 200 mg/L
- Validity criteria fulfilled:
- yes
- Conclusions:
- 81% decolorization of Reactive Black 5
- Executive summary:
The paper describes a method for
measuring the primary biodegradability
of water soluble dyestuffs under
anaerobic conditions and gives the
results obtained on 22 dyes of
commercial significance.
- Endpoint:
- biodegradation in water: inherent biodegradability
- Type of information:
- experimental study
- Adequacy of study:
- key study
- Reliability:
- 2 (reliable with restrictions)
- Rationale for reliability incl. deficiencies:
- other: Modified guideline study without information on GLP
- Qualifier:
- according to guideline
- Guideline:
- OECD Guideline 302 B (Inherent biodegradability: Zahn-Wellens/EMPA Test)
- Deviations:
- yes
- Remarks:
- see below
- Principles of method if other than guideline:
- Deviations from OECD 302 B:
concentration of dyestuff: 100 mg/l; concentration of activated sludge: 0.5 g/l dry material; feeding of the inoculum: each week 100 mg/l yeast extract (in most cases); test duration: up to 42 days; analytical methods: extinction at absorption maximum and DOC (dissolved organic carbon); initial DOC concentration: calculated from stock solution measurement - GLP compliance:
- not specified
- Oxygen conditions:
- aerobic
- Inoculum or test system:
- activated sludge, non-adapted
- Details on inoculum:
- These treatment plants received communal and/or industrial wastewater.
- Duration of test (contact time):
- 28 d
- Initial conc.:
- 13 mg/L
- Parameter followed for biodegradation estimation:
- DOC removal
- Reference substance:
- not specified
- Parameter:
- % degradation (DOC removal)
- Value:
- 0
- Sampling time:
- 28 d
- Details on results:
- 9 % adsorption after 3 h (DOC- and photometricdetermination at 580 nm)
- Validity criteria fulfilled:
- not specified
- Interpretation of results:
- not inherently biodegradable
- Conclusions:
- not biodegradable, but 60% color elimination after 28 days
- Executive summary:
DOC start [mg/L] |
DOC ads [%] |
DOC elim [%] |
DOC cat |
col ads [%] |
col elim [%] |
col cat |
elim cal |
lambda [nm] |
time [d] |
13 |
9 |
-53 |
D |
9 |
60 |
B |
- |
580 |
28 |
Not readily or inherently biodegradable
Key value for chemical safety assessment
- Biodegradation in water:
- under test conditions no biodegradation observed
Additional information
Screening tests for biodegradation of the structural analogue, Reactive Black 5, in water showed that the test substance is not readily or inherently biodegradable. However, Reactive Black 5 is rapidly removed from the dye-bath as shown by decolourisation of the test medium. The same is considered true for the close structural analogue Reactive Blue 250.
