253 
 

Journal homepage: www.fia.usv.ro/fiajournal 
Journal of Faculty of Food Engineering,  

Ştefan cel Mare University of Suceava, Romania  
Volume XII, Issue 3  – 2013, pag. 253 – 264 

 

 
 

ER YTH ROS INE B IN THE ENVI RON M ENT.  

RE MOV AL PROC ESS ES  

 
*Laura Carmen APOSTOL1, Maria GAVRILESCU2,3 

 
1Stefan cel Mare University of Suceava, Faculty of Food Engineering, 13 Universitatii Street,  

720229 Suceava, Romania; laura.apostol@fia.usv.ro    
2Gheorghe Asachi Technical University of Iasi, Faculty of Chemical Engineering and Environmental Protection, 

Department of Environmental Engineering and Management,  
73 Prof.dr.docent D. Mangeron Street, 700050 Iasi, Romania 

3Academy of Romanian Scientists, 54 Splaiul Independentei, RO-050094 Bucharest, Romania 
mgav@tuiasi.ro   

* Corresponding author 
Received March 11st 2013, accepted September 5th 2013 

 
 
Abstract: This paper presents a comparison of the resultes obteined for different methods used for the 
decolorization of the food dye Erythrosine B.  
Erythrosine B is a red odorless powder used in food industry as a colloring substance. Erythrosine B, 
also known as E 127, consists essentially of disodium 2-(2,4,5,7-tetraiodo-6-oxido-3-oxoxanthen-9-yl) 
benzoate monohydrate and subsidiary coloring matters together with water, sodium chloride and 
sodium sulphate as the principal uncolored components. The methods considered in this paper were 
sorption, biodegradation and photodegradation. Sorption demonstrated good removal efficiency in the 
presence of low-cost activated carbon from agro-waste but the treatment increases the operation cost. 
Because of Erythrosine B toxicity aerobic biodegradation processes showed to be inefficient in the 
most studies. Considering this, Erythrosine B degradation could be performed by photodegradation 
process using an adequate catalyst in order to reduce the operation cost. 
 
Keywords: food dyes, performance comparison, removal processes 
 
 
1. Introduction 
 
Food coloring is a substance that is added 
to food or drink to change its color. 
Erythrosine B (FD & C Red No. 3) is the 
only xanthene dye listed for use in food 
and ingested drugs. It is exclusively 
authorised for use in cocktail and candied 
cherries, and Bigarreaux cherries 
(94/36/EC). 
The paper presents an overview including: 
- Erythrosine B presentation in terms of its 
use as a xanthene food coloring substance; 
- the most used methods used for the 
possible decolorization of aqueous 

solutions containing the food dye 
Erythrosine B. 
 
1.1. Erythrosine B (E 127), a coloring 
substance in EU 
 
Synthetic food colors, or coal-tar/ 
petroleum colors, represent a special class 
of dyes with application in food industries.  
The main dye categories used in food 
industry are: 
- azo dyes, such as: tartrazine 
(FD&Cyellow no. 5)., ponceau (FD&C red 
no. 4), sunset yellow (FD&C yellow no. 
6); 



Food and Environment Safety - Journal of Faculty of Food Engineering, Ştefan cel Mare University - Suceava 
Volume XII, Issue 3 – 2013 

 
 

L a ur a  C a r me n AP O S TO L ,  Ma r ia  GAV R ILE SC U.  Er yt h r os i ne  b i n t h e e nvi r o nm e nt .  C o mpa r is o n o f  
r e mo va l  p r oc e s s e s,  Fo o d  a nd  E nv i r o nm e nt  S a f e t y,  V o l u me X II,  I ss ue  3  –  2 01 3 ,  p a g.  25 3  - 2 6 4  
 254

 - non azo dyes, like brilliant blue 
(FD&C blue no. 1), erythrosine 

(FD&C red no. 3), indigotin (FD&C blue 
no. 2). 
Unlike other food additives, these 
compounds need to be tested and certified 
by the official chemical examination 
bodies. Dyes approved by the Food Dye 
and Coloring Act (FD&C) are coal tar 
derivatives, contain aromatic rings. 
Erythrosine B (E 127) is a red odorless 
powder or granules with a calculated Log P 
(octanol-water) of 4.95 at 25°C, which is 
soluble in water (≤ 9% w/w) and ethanol 
[2]. The molecular weight of E 127 is 
879.84 g mol-1. It’s full chemical name is 
disodium 2-(2,4,5,7-tetraiodo-6-oxido-3-
oxoxanthen-9-yl)benzoate.  
Erythrosine B structural formula is 
presented in Fig. 1. At least 78 synonyms 
of the compound are in use. As European 
Food Safety Authority (2011) related the 
most commonly synonyms used in 
literature for Erythrosine are: CI Food Red 
14, FD & C Red No. 3, C.I. 45430, INS 
No. 127 and Erythrosine sodium [1]. 
Erythrosine B is a red odorless powder or 
granules with a calculated Log P (octanol-
water) of 4.95 at 25°C, which is soluble in 

water (≤ 9% w/w) and ethanol [2]. 
Specifications have been defined in the 
Directive 2008/128/EC7 and by JECFA 
(2006) (Table 1) [3]. 

 
Figure 1. Chemical structure of Erythrosine B 

 
Erythrosine B (E 127) consists essentially 
of disodium 2-(2,4,5,7-tetraiodo-6-oxido-
3-oxoxanthen-9-yl) benzoate monohydrate 
and subsidiary coloring matters together 
with water, sodium chloride and sodium 
sulphate as the principal uncolored 
components. The phosphorescence of 
Erythrosine B is due to the xanthene ring 
with four iodine atoms. Erythrosine B has 
phosphorescence emission time scale of 
10-5s to 10-3s corresponding to motion in 
glassy environment and is sensitive to 
oxygen [4].  

Table 1 
Specification for Erythrosine according to Commission Directive 2008/128/EC and JECFA (2006) [3] 

 
Purity Commission Directive 2008/128/EC JECFA (2006) 

Inorganic iodides calculated as sodium iodide ≤ 0.1% ≤0.1% 
Fluorescein ≤20 mg kg-1 <20 mg kg-1 
Subsidiary colouring matters ≤ 4.0% ≤4.0% 
Water insoluble matter ≤0.2% ≤0.2% 
Ether extractable matter ≤0.2%a ≤0.2%b 
Arsenic <3 mg kg-1 - 
Lead ≤10 mg kg -1 ≤2 mg kg-1 
Zinc - ≤50 mg kg -1 
Mercury ≤ 1 mg kg -1 - 
Cadmium ≤ 1 mg kg -1 - 
Heavy metals as Pb ≤ 40 mg kg -1 - 
Loss on drying at 135°C together with chloride 
and sulphate calculated as sodium salts - ≤13% 

Tri-iodoresorcinol ≤0.2% ≤0.2% 
2-(2,4-dihydroxy-3,5-diodobenzoyl) benzoic acid ≤0.2% ≤0.2% 
a from a solution of pH from 7 through 8 
b from a solution of pH not less than 7 



Food and Environment Safety - Journal of Faculty of Food Engineering, Ştefan cel Mare University - Suceava 
Volume XII, Issue 3 – 2013 

 
 

L a ur a  C a r me n AP O S TO L ,  Ma r i a GAV R ILE SC U.  Er yt h r os i ne  b i n t h e e nvi r o nm e nt .  C o mpa r is o n o f  
r e mo va l  p r oc e s s e s,  Fo o d  a nd  E nv i r o nm e nt  S a f e t y,  V o l u me X II,  I ss ue  3  –  2 01 3 ,  p a g.  25 3  - 2 6 4  
 255

 Erythrosine B, like other xanthene 
compounds, exhibits unusual 

spectroscopic and photochemical 
properties like huge absorption coefficient 
or molar extinction coefficients (λmax: 
ε524nm = 67,282 M−1 cm−1 for Erythrosine 
B; ε510nm = 60,826 M

−1 cm−1 for Eosin Y) 
in the visible region and a high tendency 
for intersystem crossing to produce a 
photochemically active triplet excited state 
[5]. 
 
1.2. Short overview on the synthesis 
process and analysis 
 
Erythrosine B, the tetraiodo- analogue of 
fluorescein, is produced by iodination (the 
reaction of iodine or potassium iodate in an 
ethanolic solution converted to the sodium 
salt) of fluorescein followed by the 
condensation of resorcinol with phthalic 
anhydride (Eq. 1) [6]. 
Erythrosine B may be converted to the 
corresponding aluminium lake by reacting 
aluminium oxide with coloring matter [1]. 
Undried aluminium oxide is usually freshly 
prepared by reacting aluminium sulphate 
or aluminium chloride with sodium 
carbonate or sodium bicarbonate or 
aqueous ammonia. Following lake 
formation, the product is filtered, washed 
with water and dried [3]. 
In the literature few methods for the 
determination of Erythrosine B in foods 
are described. These methods include High 
Performance Liquid Chromatography 
(HPLC) and capillary electrophoresis [7]. 
 
1.3. Stability, reaction and fate in the 
environment 
 

A low number of data on the fate and 
reaction of Erythrosine B in food is 
available. In general, the dyes used as 
additives are changeable in combination 
with oxidizing/reducing compounds in 
food. Dyes depend on the existence of a 
conjugated unsaturated system.  
Any compound which modifies the system 
will affect the dye (e.g. oxidising or 
reducing agents, sugars, acids, and salts) 
[8]. For exemple when cherries colored 
with Erythrosine B are stored in uncoated 
steel cans, fluorescein is readily formed 
(the production of fluorescein from 
Erythrosine B occurs in the presence of 
iron and/or tin and free organic acid as a 
result of electrochemical reduction in the 
can [9]).  
 
1.4. Use and toxicology 
 
Authorized use levels have been defined in 
the Directive 94/36/EC8 on colors for use 
in foodstuffs (Table 2). As a synthetic food 
coloring substance Erythrosine B is 
permitted in the EU for certain limited uses 
only.  
Table 2 give the main foodstuffs that are 
permitted to contain Erythrosine B up to 
specified maximum permitted levels 
(MPLs) set by Directive 94/36/EC.  
Erythrosine B has been used as a food dye 
since its approval by the U.S. Department 
of Agriculture in 1907.  
It is used in maraschino cherries, sausage 
casings, oral drugs, baked goods, and 
candies. Erythrosine B has been evaluated 
several times by JECFA and by the 
Scientific Committee for Food.  
 

 (1) 
 



Food and Environment Safety - Journal of Faculty of Food Engineering, Ştefan cel Mare University - Suceava 
Volume XII, Issue 3 – 2013 

 
 

L a ur a  C a r me n AP O S TO L ,  Ma r i a GAV R ILE SC U.  Er yt h r os i ne  b i n t h e e nvi r o nm e nt .  C o mpa r is o n o f  
r e mo va l  p r oc e s s e s,  Fo o d  a nd  E nv i r o nm e nt  S a f e t y,  V o l u me X II,  I ss ue  3  –  2 01 3 ,  p a g.  25 3  - 2 6 4  
 256

  Table 2 
Food Dye Certification [10] 

 

Food dye 
Pounds of 
total dye 
certified 

Percentage of 
total 

Blue 1 711 659 4.7 
Blue 2 550 883 3.7 
Citrus Red 2 1 764 0 
Green 3 15 817 0.1 
Orange B 0  0 
Erythrosine B 216 235 1.4 
Red 40 6 203 374 41.3 
Yellow 3 3 765 331 25 
Yellow 6 3 338 351 23.7 

Total 15 016 634 100 
 

Table 3 
Maximum permitted usage levels of Erythrosine 

B according to European Parliament and 
Council Directive 94/36/EC [11] 

 

Foodstuffs Maximum Permitted Level (mg/kg) 
Cocktail cherries and 

candied cherries 
200 

Bigarreaux cherries in 
syrup and in cocktail 

150 

 
The US Code of Federal Regulation, states 
that FD&C Red No.3 (Erythrosine B) may 
be safely used as a coloring in general 
foods in amounts consistent with Good 
Manufacturing Practice (GMP) [12].  
Erythrosine B is permitted in the USA for 
general use in sweets and foods marketed 
to children such as candies, popsicles, cake 
frosting and cake-decorating gels.  
The report provided by United States Food 
and Drug Administration (US FDA) 
indicate that under experimental conditions 
Erythrosine B at high dose levels (4% in 
the diet) can affect the level of circulating 
thyroid hormones in rats, thus leading to an 
increase in the incidence of thyroid tumors. 
The response of the US FDA in 1990 was 
withdrawal of permission to use 
Erythrosine B lakes (salts), but not 
Erythrosine B, in all foods, drugs and 
cosmetics, and to withdraw the use of 

Erythrosine in cosmetics and externally 
applied drugs [1]. 
In Australia, the Code restricts the use of 
Erythrosine B in foods. It is used just to 
preserved cherries (maraschino cherries), 
cocktail cherries or glace cherries. The dye 
is used prior to processing.  
Food Standards Australia New Zealand 
(FSANZ) have proposed extending the 
permitted uses to products such as icing 
and frostings used in other foods that are 
more widely consumed (e.g. cakes, 
biscuits, fancy breads) [13]. 
In EU, Erythrosine B is used in 
manufacturing photographic plates, for 
microscopic stains, pharmaceuticals and 
cosmetics. In June 2010, the Scientific 
Committee on Consumer Safety published 
an opinion on Erythrosine use in toothpaste 
products. GlaxoSmithKline (GSK) 
considered Erythrosine B safe for 
consumers when used as a colorant in 
toothpaste products with a maximum 
concentration of 0.0025% (25 ppm) and 
estimated exposure from this use to be 
0.0002 mg/kg bw/day (Table 4) [1]. 
 

Table 4 
Toxicological parameter of xanthene dye 

Erythrosine B [13] 
 

 
 
 
Accepted Daily Intake = 
0 - 0.1 mg kg-1 bw-1 day-1 
 
 
 
NOEL = 60 mg person-1 
day-1 (mg kg-1 bw-1 day-1) 

Toxicological 
parameter 

Value 
[mg 
kg-1] 

LD50 (rat), 
intraperitoneal 
LDLo (rat), 
intravenous 
LDLo (rabbit), 
intravenous 
LDLo (mouse), 
oral 
LD50 (mouse), 
intravenous 

300 
 
200 
 
200 
 
2500 
 
370 

 
2. Removal of Erythrosine B from 
wastewater 
 
Food once was colored only with natural 
dyes, coming mainly from various plants. 



Food and Environment Safety - Journal of Faculty of Food Engineering, Ştefan cel Mare University - Suceava 
Volume XII, Issue 3 – 2013 

 
 

L a ur a  C a r me n AP O S TO L ,  Ma r i a GAV R ILE SC U.  Er yt h r os i ne  b i n t h e e nvi r o nm e nt .  C o mpa r is o n o f  
r e mo va l  p r oc e s s e s,  Fo o d  a nd  E nv i r o nm e nt  S a f e t y,  V o l u me X II,  I ss ue  3  –  2 01 3 ,  p a g.  25 3  - 2 6 4  
 

 

257

By the 19th Century, colors began to 
derive from other chemicals so that 

they came into use with sometimes serious 
health consequences. 
Erythrosine B is still permanently listed for 
use in ingested drugs and food, such as 
baked goods, cherries, dairy products, 
desserts, dietary supplements, food 
seasonings, jellies, jams, and vegetable 
products. 
Acid dye like Erythrosine B can be lost in 
effluents in percentage varying from 5 to 
20%, since low adsorption occurs for acid 
and reactive dyes, while high adsorption 
occurs with basic and direct dyes and high 
to medium for disperse dyes [14; 15].  
Ryvolova et al. [16] and Ramakrishnan et 
al. [17] found that the concentration of 
colorants in foods and drugs, respectively 
were between 0.3 and 0.03 mg mL−1. In 
this situation, it was estimated that a high 
amount of dye results as waste and has to 
be treated (Table 5) [16; 17].  
Erythrosine B contained in aqueous 
solutions was subjected to different 
decolorization methods, including 
physical, chemical, and biological 
processes. Some of them are discusses 
below. 

 
Table 5 

Amount of Erythrosine B  
contained in different products 

 
Product Erythrosine B (µg mL-1) 

Cherry 235 
Cream biscuits 316.65 
Gems 177.8 
Candies 36.74 
Ibuprofen 5.6 (µg/tablet) 
 
2.1. Sorption 
 
Sorption is widely used for dye removal 
from wastewaters. Activated carbon, the 
universal adsorbent used for pollutant 
removal, although reasonably effective at 
removing dyes from aqueous streams, 
needs either regeneration or disposal, once 

it is fully loaded. Other limitations are the 
high cost and 10-15% loss of adsorbent 
during reactivation [14].  
In recent years, many investigations have 
been undertaken to evaluate inexpensive 
alternative materials of biological origin 
(biosorbents) as potential adsorbents for 
dyes, which include feathers [18], de-oiled 
mustard [19], montmorillonite [20], bottom 
ash and de-oiled soya [21], fungi [22].  
Due to its low cost and widespread 
availability, biomass has been extensively 
investigated as sorbent for removing color, 
with promising results. In this case, 
biomass refers to dead plant and animal 
matter resulting from agriculture, forest, 
fermentation and shellfish by-products or 
wastes.  
Other unconventional biosorbents used for 
sorptive removal of different dye classes 
are pinus bark powder [23], hazelnut shells 
[24], nut shells [25], or bagasse pith [26]. 
The main mechanisms found responsible 
for the decolorization of aqueous solutions 
containing dyes are adsorption and ion 
exchange.  
Agricultural wastes can be good sorbents 
for the removal of pollutants, since they 
involve reduced costs for operation and 
waste disposal, providing a cheap 
alternative to existing commercial 
activated carbons.  
Vegetal hull/husk was applied as a raw 
material for producing sorbents with the 
following advantages:  
(1) appropriate chemical composition;  
(2) low cost;  
(3) high dispersity;  
(4) scaly structure and developed porous 
surface ensuring a high surface-to-volume 
ratio [27]. 
Several studies reported chemical 
modifications of celluloses and ligno-
celluloses extracted from cotton waste, 
sawdust and corn stalks in order to increase 
the number of active centers for dye 
immobilization on sorbent surface [28].  
 



Food and Environment Safety - Journal of Faculty of Food Engineering, Ştefan cel Mare University - Suceava 
Volume XII, Issue 3 – 2013 

 
 

L a ur a  C a r me n AP O S TO L ,  Ma r i a GAV R ILE SC U.  Er yt h r os i ne  b i n t h e e nvi r o nm e nt .  C o mpa r is o n o f  
r e mo va l  p r oc e s s e s,  Fo o d  a nd  E nv i r o nm e nt  S a f e t y,  V o l u me X II,  I ss ue  3  –  2 01 3 ,  p a g.  25 3  - 2 6 4  
 

 

258

 
Table 6 

Sorbents tested for xanthene dye removal 
 

Dye Initial dye conc. (x 10-5 mol L-1) Sorbent 
q 

(x 10-5 mol g-1) Ref. 

Rhodamine B 

2 - 200 fungi 8.15 [22] 
5 - 50 activated carbon 4.57 [33] 

4 - 400 algae 16.7 [34] 
10 - 50 baryte 34.22 [35] 

Eosin Y - sun-dried jute fiber 4.55 [36] 1 - 70 chitosan hydrobeads 11.57 [37] 

Erythrosine B 

1 – 6 bottom ash de-oiled soya 
2.37 
1.20 [21] 

1 – 6 hen feathers 2.31 [18] 

1 - 9 de-oiled mustard activated carbon 
13.15 
19.9 [19] 

5 - 10 montmorillonite 1.5 [20] 
5 - 40 Activated carbon 47.28 [38] 

 
Adsorption of reactive dyes by sawdust 
chars and activated carbon [29]; methylene 
blue by waste Rosa canina sp. seeds [30]; 
anionic dyes by modified coir pith [31]; 
and methylene red by acid-hydrolysed 
beech sawdust [32] has also been reported. 
Table 6 presents a summary of the 
biosorbents used for xanthene dye 
removal. 
 
2.2. Biodegradation 
 
Biological processes involve the aerobic 
(presence of oxygen) or anaerobic (absence 
of oxygen) degradation of organic 
substances by microorganisms. 
Anaerobic biological reduction of dyes has 
been investigated from different 
perspectives, i.e. degradation and color 
removal. Anaerobic reducing conditions 
found in the environment include 
sediments at the bottom of streams of 
certain sections of landfills where there is 
no oxygen. Anaerobic bioremediation of 
soluble dyes to undergo decolorization by 
breaking them into less toxic compounds 
has been widely investigated [14]. The 
decolorization in the case of azo dyes 
occurs due to azo reduction [39]. 
Additional carbon is required for 
decolorization to proceed the process at a 
viable rate: this is converted into methane, 

hydrogen sulphide and carbon dioxide 
[40]. This additional carbon source may be 
a limiting factor from a commercial 
perspective. In many situations, 
decolorization of reactive dyes under 
anaerobic conditions is due to the action of 
a ‘reductase’ enzyme. If complete 
mineralization occurs, conversion of 
organic contaminants into methane and 
oxygen leads to production of bioga,s 
which is a major attraction because of heat, 
power and reduced energy costs [14]. 
In the case of toxic compounds interactions 
with living microorganisms two pathways 
can be considered:  
i) when biodegradation starts with 
chemical interactions, the sorption rate 
limits the biodegradation;  
ii) when biodegradation starts after some 
lag period, the chemical has time to sorb 
before degradation begins, and slow 
sorption causes biodegradation to be 
desorption-rate limited [41].  
However, the toxicity of certain dyes 
inhibits the complete mineralization.  
Xanthene dyes have been reported to be 
toxic to various species tested in laboratory 
conditions. Several reports on enzymatic 
oxidation of xanthene dyes are available 
[42; 43; 44; 45; 46; 47]. Enzymatic 
reduction of xanthene compounds was not 
reported.  



Food and Environment Safety - Journal of Faculty of Food Engineering, Ştefan cel Mare University - Suceava 
Volume XII, Issue 3 – 2013 

 
 

L a ur a  C a r me n AP O S TO L ,  Ma r i a GAV R ILE SC U.  Er yt h r os i ne  b i n t h e e nvi r o nm e nt .  C o mpa r is o n o f  
r e mo va l  p r oc e s s e s,  Fo o d  a nd  E nv i r o nm e nt  S a f e t y,  V o l u me X II,  I ss ue  3  –  2 01 3 ,  p a g.  25 3  - 2 6 4  

259 
 

Borgerding and Hites (1994) reported the 
presence of xanthene dye Erythrosine B in 
wastewater from food and cosmetic 
industry and affirmed that the dye was 
adsorbed by the sludge [48]. Itoh and 
Yatome (2004) studied the decolorization 
of six xanthene dyes by a white rot fungus, 
Coriolus versicolor but only three of them 
were degraded [45]. Table 7 presents a 
summary of xanthene dyes removal by 
enzymatic mechanism. 
 
2.3. Photodegradation 
 

Because processes like adsorption or 
biodegradation can generate secondary 
pollutants, AOP like photocatalytic 
degradation represented an alternative for 
the removal of hazardous xanthene dye 
from effluents [49].  
AOPs are effective for detoxification and 
mineralization of dyes from wastewaters 
and research studies have shown promising 
results as these processes appear to have 
the ability to completely decolorize and 
partially mineralize the pollutants from 
dye-industry in short reaction time [50; 5].  
 

Table 7 
Xanthene dyes removal by biodegradation 

 

Dye Initial dye conc.  (x 10-5 mol L-1) Biomass 
R (%) 

r (μM min−1 mg−1)* Ref. 

Fluorescein 10 Fungus  Coriolus versicolor 
85.0 
10.2 

[45] 

4 - Amino 
fluorescein 10 

Fungus  
Coriolus versicolor 

95.0 
6.7 

5 - Amino 
fluorescein 10 

Fungus  
Coriolus versicolor 

91.9 
7.2 

Rhodamine B 
10 Fungus  Coriolus versicolor 0 

5 Laccase Mediator System (LMS) 80% [46] 
40 LiP of fungus Phanerochaete chrysosporium 46.0 [44] 

Rhodamine 123 10 Fungus  Coriolus versicolor 0 [45] 

Rose bengal - Fungus strain Aspergillus Wentii 89.3 [43] 

Erythrosine B 

10 Mold Neurospora crassa - [47] 

- Aerobic sludge 0 [48] 

30 Anaerobic granular sludge 20 – 70 1.5 h-1* [38] 

*first order degradation rate 
 

Table 8 
Xanthene dye removal by chemical degradation process 

 

Dye Initial dye conc. (x 10-5 mol L-1) 
Catalyst 

(UV) R (%) Ref. 

Eosin Y 10 TiO2 P25  78 [51] 

Rhodamine B 5 0.65 g L
-1 TiO2 80 [52] 

1 SiO2@TIO2 90 [53] 
Rhodamine 6G 5 1 g L-1 ZnO 80 [54] 

Fluorescein  ZnO 44.4 [55] 
Phloxine B 10 0.04 g L-1 TiO2 82 [19] 

Erythrosine B 

10 2 g L-1 TiO2 P25 35 [56] 10 g L-1 ZnO  60 
10 0.5 g L-1 TiO2 Aeroxide 99 [57] 
20 Electrochemical degradation 95 [58] 

 



Food and Environment Safety - Journal of Faculty of Food Engineering, Ştefan cel Mare University - Suceava 
Volume XII, Issue 3 – 2013 

 
 

L a ur a  C a r me n AP O S TO L ,  Ma r i a GAV R ILE SC U.  Er yt h r os i ne  b i n t h e e nvi r o nm e nt .  C o mpa r is o n o f  
r e mo va l  p r oc e s s e s,  Fo o d  a nd  E nv i r o nm e nt  S a f e t y,  V o l u me X II,  I ss ue  3  –  2 01 3 ,  p a g.  25 3  - 2 6 4  
 260

  
Photodegradation is based on the 

degradation of a molecule mediated by the 
absorption of photons. Photocatalytic 
degradation of several xanthene 
contaminants using large bandgap 
semiconductor particles (such as TiO2, 
ZnO, WO3) has been extensively studied.  
Table 8 shows data on xanthene dye 
photodegradation in the presence of 
different catalysts. 
 
3. Comparison of physico-chemical and 
bological processes applied for the 
decontamination of aqueous sollutions 
polluted with Erythrosine B 
 
Physico-chemical and biological methods 
that are effective in the elimination of dye 
have been studied. Each process has its 
own constraints in terms of cost, 
feasibility, practicability, reliability, 
stability, environmental impact, sludge 
production, operational difficulty, pre-
treatment requirements, the extent of the 
organic removal and potential toxic by-
products. Even if a process is reported to 
be successful in decolorizing a particular 
effluent, the same may not be able to other 
type of colored aqueous solution. The use 
of a single process may not be efficient in 
the complete decolorization of the polluted 
effluent.  
The comparison of different processes used 
for dyes removal from aqueous solution is 
of interest to establish the conditions for 
removal performance (the most efficient 
experimental conditions for the elimination 
of compound from solution) and to provide 

useful information for the essential aspects 
of the combination of different processes 
[59]. 
Sorption, biodegradation and 
photodegradation processes where tested to 
evaluate Erythrosine B removal from 
aqueous solution. 
Table 9 summarizes the conditions and the 
performances of the processes obteined for 
300 mg L-1 Erythrosine B (the higer dye 
concentration tested) removal from 
aqueous solution.  
Sorption process resulted in 65% – 90% 
removal efficiency at 50°C and natural pH 
of the solution (pH=5.6) for a contact time 
of around 21h [60].  
Photodegradation using fixed or suspended 
TiO2 yielded very high color removal 
(95%), within the same contact time like 
sorption study also at natural pH and 
resulting nontoxic products.  
Anaerobic biodegradation treatment has 
demonstrated to be affected by Erythrosine 
B toxicity at high concentration (0.4 mM) 
and low color removal was achieved for 
the same biomass amount as with sorption 
study (20 g L-1) [38].  
Sorption process demonstrated to have 
good removal efficiency especially at 
higher temperature (50°C) where the dye 
amount adsorbed per sorbent unit was 
between 14.1 and 16.4 mg g-1 for BH and 
PSH respectively. Sorption of Erythrosine 
B demonstrated a ~5-fold increase of dye 
adsorption in the presence of low-cost 
activated carbon in the study conducted by 
Jain and Sikarwar (2009) but agro-waste 
treatment increases the operation cost [19].  

 
Table 9 

Erythrosine B removal using physico-chemical and biological methods under different condition 
 

Process applied Experimental condition 
Amount of dye uptake 

(mg g-1) 
Removal efficiency 

(%) Observation 

Sorption using agro-
waste 

Ci=300 mg L
-1 

Contact time = 
21h 

14.1 - 16.4 mg g-1  
(BH and PSH) 

65 – 80 
(BH and PSH) 

Csorbent= 20 g L
-1 

t=50°C 
Anaerobic 

Biodegrdation 3 mg g
-1 30 Cbiomass= 20 g L

-1 

t=37°C 
Photocatalytic 
degradation - 95 

CTiO2= 0.5 g L
-1 

ti=25°C 



Food and Environment Safety - Journal of Faculty of Food Engineering, Ştefan cel Mare University - Suceava 
Volume XII, Issue 3 – 2013 

 
 

L a ur a  C a r me n AP O S TO L ,  Ma r i a GAV R ILE SC U.  Er yt h r os i ne  b i n t h e e nvi r o nm e nt .  C o mpa r is o n o f  
r e mo va l  p r oc e s s e s,  Fo o d  a nd  E nv i r o nm e nt  S a f e t y,  V o l u me X II,  I ss ue  3  –  2 01 3 ,  p a g.  25 3  - 2 6 4  
 261

  
The results obtained for 

biodegradation study confirmed the 
biomass capacity to adsorb Erythrosine B 
based on the biomass color at the end of 
the study. Similar result was obtained by 
Chamam et al. (2007) for a sulphuric 
textile dye, Cassulfon CMR, using 
activated sludge for the batch sorption test 
[61].  
For the range of Erythrosine B 
concentrations studied (30 and 300 mg L-1) 
dye photodegradation in the presence of 
TiO2 represent the most efficient method 
than sorption and biodegradation in the 
removal of Ery B in aqueous solution. Ong 
et al. (2009) compared the sorption and 
photodegradation of BB3 and RO16 and 
observed also a higher efficiency for 
photodegradation using TiO2 that in the 
sorption study using modified rice hull 
[62].  
The decolorization rate was observed to be 
different for each system, for the first 60 
min of reaction the relative order evaluated 
was: sorption > photodegradation >> 
biodegradation. 
The combination of different methods for 
the removal of dyes from aqueous solution 
sounds to be an ideal solution for the 
present need of time. A combination of 
AOP and biological treatment showed 
better results for the color removal from 
dyeing effluents containing hazardous 
compounds [63]. 
The scientific knowledge represented an 
important element for managing the 
direction and improvement of techniques 
applied for dye removal from effluents. In 
view of the need for a technically and 
economically satisfying treatment 
technology, an abundance of technologies 
were proposed and tested [40]. 
 
4. Conclusions 
 
Erythrosine B or FD&C Red No.3 is a 
cherry-pink/red synthetic coal tar dye. It is 

most popularly used as food coloring and a 
host of other applications, such as printing 
inks, biological stain, and for extraction-
photometric determination of K, Cd, Pb, 
Mn, Zn, Ag. Erythrosine B was the subject 
of different decolorization methods applied 
to aqueous solutions containing dye. 
Sorption demonstrated good removal 
efficiency in the presence of low-cost 
activated carbon from agro-waste but the 
treatment increases the operation cost. 
Because of Erythrosine B toxicity aerobic 
biodegradation processes showed to be 
inefficient in the most studies. Considering 
this, Erythrosine B degradation could be 
performed by photodegradation process 
using an adequate catalyst in order to 
reduce the operation cost (with irradiation 
time). 
 
5. Acknowledgments  
 
This work was supported by the Romanian 
National Authority for Scientific Research, 
CNCS-UEFISCDI, project number PN-II-
ID-PCE- 2011-3-0559, Contract 265/2011 
and BRAIN project (ID 6681, European 
Social Found and Romanian Government). 
 
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