Textile industry is one of the most polluting industries in the world. It has a high importance in terms of its environment impact, since it consumes a considerably large amount of water and produces highly polluted discharge water. In this work, characterization of toxic organic compounds is proposed. Based on gas chromatography coupled to mass spectrometry (GC/MS) screening analysis, organic micropollutant diversity of textile effluents from a local textile processing factory was investigated. In the present work, physicochemical characterization of the studied textile effluents showed considerably high values of principal pollution parameters above the prescribed discharge water limits. Heavy metals like zinc (Zn), copper (Cu), iron (Fe), nickel (Ni), cadmium (Cd), chromium (Cr), and lead (Pb) were found to be present within the permissible limits. The results of GC/MS revealed the presence of various organic compounds belonging to a wide range of chemical classes. Main groups of chemical compounds detected in these effluents were aromatic carboxylic acids, alkanes, aromatic amines, phthalates, aliphatic carboxylic acids, and linear aliphatic alcohols. The results of this study allowed significant contributions to the chemical characterization of textile industry contaminants and identification of indicators that can be considered an important tool for assessment of the potential impact of textile activities to the contamination of aquatic environment and health hazard.
Because of the increase of various types of industrial effluents, there is a growing concern regarding the potentially adverse effects of textile effluents on aquatic biota and humans due to the contamination of water used in textile industry. Being emitted at a significant concentration level, organic compounds in textile effluents normally present a high structural diversity and reveal notable ecotoxicological effects. Determination of nonhalogenated solvents (toluene, xylenes, ethylbenzene, and diisobutylketone) in textile industrial wastewater was performed with head-space solid phase microextraction h-SPME [
Significant amounts of polyethylene glycol, polyethoxylate decylalcohol, and linear alkylbenzene sulfonates were found to be major constituents in textile wastewaters. High concentration levels were found for some benzenes and naphthalene sulfonates which are used in the textile industry as dye bath auxiliaries [
Moroccan industrial sector is composed of 6070 units in which 31% are textile and leather industries. These industries consume significant quantities of dye and chemicals products in the various manufacturing synopsis [
The discharge of textile effluents into natural aquatic and terrestrial ecosystems poses serious problems. The hazard linked to these effluents resides mainly in the presence of micropollutants. These chemical compounds are persistent contaminants and bioactive which means that they are not completely biodegradable and cannot be removed with conventional water treatment technologies.
It has to be stated that there is a lack of systematic investigations on organic pollutants in textile effluents as well as of the information on their environmental relevance. Like other city industries in the country, textile industries of Fez city discharge their wastewater into the sewage network without any prior treatment. Moreover, in our previous work, we found high genotoxicity and phytotoxicity potential of textile effluents from the studied site of Fez city [
Samples of textile effluent used in this study were collected from a textile factory of 3200 m2 surface, located at Sidi Brahim industrial area in Fez, Morocco. This factory produces cotton and polyester clothes, discharging more than 400 m3/day of wastewater, which originates from different manufacturing processes (singeing, desizing, scouring, bleaching, mercerizing, dyeing, printing, and finishing). The scheme of sampling site is shown in Figure
Scheme of production processes in sampling site and the main pollutants from each step.
Physicochemical analyses of textile effluents were performed to evaluate some major parameters including pH, temperature (T), electric conductivity (EC), total suspended solids (TSSs), total dissolved solids (TDSs), chemical oxygen demand (COD), biological oxygen demand during 5 days at 20°C (BOD5), P-phosphates (P-
Metal ions (Fe, Cd, Pb, Cr, Cu, Zn, and Ni) and divalent cations (Mg2+ and Ca2+) were determined using the plasma-absorption emission spectroscopy method with an atomic absorption spectrophotometer (Activa, Horiba Jobin Yvon) [
Before subjecting to GC/MS analysis, the organic compounds contained in textile wastewater samples were extracted. A sequential liquid-liquid extraction procedure was applied to approximately 500 ml of textile wastewater using dichloromethane. Equal volume of dichloromethane was used for extraction. Thereafter, the organic layers were concentrated (approx. 1 ml) by rotary evaporation at 40°C under reduced pressure and dried by filtration over 1 g of anhydrous granulated sodium sulfate. The final concentration volume of wastewater extracts was 50
Organic compounds contained in textile wastewater samples were determined in accordance with the method reported by Giorgetti et al. [
The textile effluent samples collected from the studied site during production process were characterized with common parameters (color, temperature, pH, EC, TSS, and COD). The mean and standard deviations were calculated using 3 different effluents during the experimental period. Main results are presented in Table
Physicochemical characterization of textile effluents compared with M.D.Q.S and WHO standards.
Parameters | Units | M.D.Q.S limits | WHO standards | Effluent A | Effluent B | Effluent C | Average | S.D (±) |
---|---|---|---|---|---|---|---|---|
Color | — | — | — | Blue | Dark blue | Black | — | — |
T | °C | 30 | 40 | 45 | 40 | 41 | 42 | 2.64 |
pH | 5.5–8.5 | 6.5–8.5 | 7.2 | 7.9 | 8.1 | 7.73 | 0.47 | |
EC | 2700 | 1200 | 1240 | 13670 | 1520 | 5476.66 | 7097.01 | |
TDS | mg·l−1 | — | 2000 | 1510 | 3025 | 2400 | 2311.66 | 761.35 |
TSS | mg·l−1 | 30 | 100 | 900 | 2200 | 1200 | 1433.33 | 680.68 |
COD | mg·l−1 | 120 | 250 | 1026 | 2433 | 1766 | 1741.66 | 706.81 |
BOD | mg·l−1 | 40 | 30 | 200 | 880 | 360 | 480 | 355.52 |
P- | mg·l−1 | — | — | 0.461 | 0.788 | 1.147 | 0.798 | 0.343 |
N- | mg·l−1 | — | — | 0.670 | 1 | 7.3 | 2.99 | 3.73 |
N- | mg·l−1 | — | — | 10.8 | 0.29 | 1.45 | 4.18 | 5.76 |
Ca | mg·l−1 | — | — | 88.54 | 210.44 | 13.8 | 104.26 | 99.25 |
Mg | mg·l−1 | — | — | 25.29 | 51.97 | 4.85 | 27.37 | 23.62 |
Zn | mg·l−1 | 5 | 1 | 0.04 | 0.28 | 0.05 | 0.123 | 0.13 |
Cu | mg·l−1 | 3 | 0.1 | 0.004 | 0.032 | 0.002 | 0.0126 | 0.016 |
Fe | mg·l−1 | 5 | 10 | 0.649 | 0.584 | 0.401 | 0.544 | 0.128 |
Ni | mg·l−1 | 5 | 3 | 0.02 | 0.01 | 0.001 | 0.010 | 0.009 |
Pb | mg·l−1 | 1 | 0.1 | 0.05 | 0.002 | 0.03 | 0.031 | 0.024 |
Cd | mg·l−1 | 0.2 | 2 | 0.001 | 0.032 | 0.041 | 0.024 | 0.020 |
Cr | mg·l−1 | 0.5 | 2 | 0.021 | 0.011 | 0.045 | 0.025 | 0.017 |
The studied textile effluents are characterized by a variation in color from blue, dark blue, and black. This variation of discharged textile effluents color is due to the variation of the dyes and pigments used during production process. The pH of textile effluent samples varied from 7.2 to 8.1 with a mean value of 7.73 indicating the alkalinity of the effluent samples. The results were similar to the study conducted by Islam and Mostafa [
The temperature recorded in textile effluents was high (40–45°C) and exceeded the standards set by M.D.Q.S and WHO. The high temperature of these effluents can induce corrosion of the sewerage network by catalyzing redox reactions [
The EC indicates dissolved substances in an aqueous system. It depends on the dissociation of ions, their concentration, temperature, and migration in the electric field, but it does not give any idea about the type of ions present [
The amount of TDS which was found to be 1510, 3025, and 2400 mg·l−1, respectively, in the textile effluents A, B, and C was similar to the observation made by Ali et al. [
Chemical oxygen demand (COD) shows the presence of both the biodegradable and non-biodegradable matter content in the textile effluents. In this study, total COD in various textile effluents varied from 1026 to 2433 mg·l−1, exceeding the limits set by M.D.Q.S and WHO. Shammi et al. [
The amount of N-Nitrate (N-
Divalent cations Ca2+ and Mg2+ showed high concentration (mg·l−1) variability in the effluent samples, reflected by high standard deviation values (104.26 ± 99.25 and 27.37 ± 23.62, respectively). Finally, heavy metal analysis of textile effluents showed low concentrations compared to the M.D.Q.S and WHO standard. The average concentration (mg l−1) of heavy metals like Cu(0.0126), Ni (0.01), Pb (0.031), Cd (0.024), and Cr (III) (0.025) was considerably low (<0.04 mg·l−1) while it kept > 0.1 mg l−1 in case of Zn (0.13) and Fe (0.544). The relative dominance (average) of heavy metals in textile effluents was observed in the following sequence: Fe > Zn > Pb > Cr > Cd > Cu > Ni.
Table
There was observed high values of TSS and TDS in effluent samples which correspond to filterable and nonfilterable residues, respectively. TSS and TDS are important repositories for toxic heavy metals and dyes [
Similar to the toxic dyes and pigments of organic nature, such as C.I. Pigment Yellow-12 (3,3-dichloro benzedine), C.I. Disperse Yellow-7 (P-amino azobenzene), and C.I. Direct Yellow-1 (benzedine), salts, acids, alkalis, and bleaching and finishing agents are also highly harmful and affect the health of biota to a great extent. The effects of the pollutants may not be quite evident immediately but with the passage of time their imperceptible effects are of fatal nature [
It can then be concluded that the textile wastewater used in this experiment was highly variable and suffered from low biodegradability and high inorganic solid content (both soluble and suspended). This wide variation in the characteristics of textile wastewater is due to the complexity of materials used in the textile industry during the processing of textiles.
Textile effluents from the studied site were subject to organic analyses. Based on the GC/MS analysis of different textile effluents from the studied site, identification of a large number of various organic contaminants has been performed. The obtained results demonstrated high structural diversity of organic chemical pollutants in the textile wastewaters. It is important to notice that only a restricted number of samples have been investigated as a preliminary evaluation of a potential impact of textile contaminants from diverse production processes at industrial site on the aquatic environment. Selected environmentally relevant specific organic compounds identified in three different textile effluents are presented in Tables
Organic compounds identified in real textile effluent A.
Compound | RT (min) | RA (%) |
---|---|---|
Ethyl alcohol | 4.35 | 0.11 |
Tert-butyl hydroperoxide | 4.89 | 0.32 |
Methane, trimethoxy- | 5.38 | 0.20 |
Pentane, 2,2-dimethyl- | 9.08 | 0.17 |
Acetic acid, 1-methylethyl ester | 9.41 | 0.13 |
Cyclohexane | 9.93 | 0.34 |
Hexane, 2,4-dimethyl- | 10.09 | 0.13 |
Hydroxylamine,O-(2 methylpropyl) | 10.20 | 0.10 |
Diacetyl sulfide | 10.90 | 0.29 |
Propanoic acid, ethyl ester | 11.04 | 0.13 |
Acetaldehyde, tetramer | 14.70 | 0.30 |
2-(Acetomethyl)-1- butene | 15.00 | 0.21 |
Isocrotonic acid (2-Butanoic acid) | 15.28 | 0.32 |
Acetol | 15.69 | 0.23 |
Acetic acid, ethoxy-, ethyl ester | 18.14 | 0.11 |
Ketone, methyl 2-methyl-1,3-oxothiolan-2-yl | 19.14 | 0.31 |
Oxirane, (1-methylbutyl)- | 20.44 | 0.35 |
2-Isopropyl-3-vinyloxirane | 20.97 | 0.10 |
Glyceraldehyde diethylacetal | 24.39 | 0.22 |
Benzene, 1-methyl-2-(1-methylethyl)- | 25.10 | 0.18 |
Undecane, 2,6-dimethyl- | 25.93 | 0.19 |
Octadecane, 3-ethyl-5-(2-ethylbutyl)- | 26.57 | 0.09 |
Pentadecanoic acid,2,6,10,14-tetramethyl-, methyl ester | 26.74 | 0.10 |
1-Butanol, 3-methyl-, acetate | 29.80 | 0.21 |
4-Nitrobenzyl idenene malonic acid, diethyl ester | 43.53 | 0.45 |
Ethanol,2-[4-(1,1dimethylethyl)phenoxy] | 48.01 | 0.12 |
Phenol,4-[2-[2-(chloromethyl)-1,3-dioxolan-2-yl]ethyl]-, acetate | 48.33 | 0.10 |
Propane dioic acid, [(4methoxyphenyl) methylene]-, diethyl ester | 49.37 | 0.25 |
Cyclohexane-1,3-dicarboxylic acid, 2-(4-methoxyphenyl)-4,6-dioxo-, diethyl ester | 53.26 | 0.12 |
Hexadecane, 2-methyl- | 53.36 | 0.12 |
Tetratriacontane | 54.35 | 0.09 |
2-Secoandrosta-1,6-diene-17,19-diol,2-cyano-4-methylene-, diacetate | 55.76 | 0.59 |
10a,12a-Dimethyl-hexadecahydro-2-oxa-chrysen-3-one | 56.91 | 0.13 |
Phthalic acid, 6-ethyloct-3-yl 2-ethylhexyl ester | 59.03 | 0.39 |
Dodecanoic acid | 60.79 | 0.10 |
Docosanoic acid, 2-hydroxy-, methyl ester | 61.95 | 0.12 |
RT: retention time; RA: relative abundance. 1–12Organic compounds corresponding to peak numbers on the chromatogram referring to effluent A in Figure
Organic compounds identified in real textile effluent B.
Compound | RT (min) | RA (%) |
---|---|---|
Acetone | 4.83 | 0.32 |
Formic acid, ethyl ester | 5.40 | 0.25 |
Methylglyoxal | 7.24 | 0.28 |
Acetic acid, 1-methylethyl ester | 9.47 | 0.48 |
Ethaneperoxoic acid, 1-cyano-1-(2-methylphenyl)ethyl ester | 10.94 | 0.37 |
Propanoic acid, ethyl ester | 11.07 | 0.42 |
Cyclobutene, 2-propenylidene- | 13.51 | 0.57 |
Ethanol, 2-(1-methylethoxy)- | 14.70 | 0.47 |
Acetic acid, 1-methylethyl ester | 15.02 | 0.28 |
Isocrotonic acid | 15.37 | 0.66 |
Diacetyl sulfide | 15.69 | 0.34 |
Acetic acid, ethoxy-, ethyl ester | 18.15 | 0.18 |
Pentanoic acid, 3-methyl-4-oxo- | 18.50 | 0.17 |
Ketone, methyl 2-methyl-1,3-oxothiolan-2-yl | 19.15 | 0.48 |
Butanoic acid, 2-methyl-, ethyl ester | 20.43 | 0.13 |
Undecane, 2,6-dimethyl- | 22.52 | 0.18 |
2,3-Butane diol-diacetate | 23.43 | 0.15 |
1,1-Ethanediol, diacetate | 24.19 | 0.15 |
Glyceraldehyde diethylacetal | 24.39 | 0.38 |
2,3-Dimethyldecane | 25.00 | 0.13 |
Ethyl -3-acetoxybutyrate | 25.17 | 0.42 |
Octane, 5-ethyl-2-methyl- | 25.93 | 0.40 |
Methanol, oxo-, benzoate | 26.94 | 0.15 |
Butanedioic acid, diethyl ester | 27.33 | 0.25 |
4,4-Ethylenedioxy-1-pentylamine | 27.75 | 0.15 |
Methoxyacetaldehyde diethyl acetal | 27.89 | 0.21 |
1-Butanol, 3-methyl-, acetate | 29.81 | 0.34 |
(5-Chloro-3-cyano-4,6-dimethyl-pyridin-2-ylsulfanyl)-acetic acid ethyl ester | 47.74 | 0.14 |
Propanedioic acid, [(4-methoxyphenyl)methylene]-, diethyl ester | 49.37 | 0.37 |
Benzofurane-3-carboxylic acid, 5-methoxy-2-(1-piperidylmethyl)-, ethyl ester | 53.25 | 0.14 |
2-Isopropyl-10-methylphenanthrene | 53.56 | 0.15 |
1-Methyl-2,6-diphenyl-4,4-tetramethylene-1,4-dihydropyridine-3,5-dicarbonitrile | 55.76 | 0.83 |
RT: retention time; RA: relative abundance. 13–21Organic compounds corresponding to peak numbers on the chromatogram referring to effluent B in Figure
Organic compounds identified in real textile effluent C.
Compound | RT (min) | RA (%) |
---|---|---|
Hydroxylamine, | 4.08 | 0.94 |
Benzene, (1,2,2-trimethoxyethyl)- | 5.13 | 0.03 |
8a-Methyl-5-methylene-3-([(pyridin-2-ylmethyl)-amino]-methyl)-decahydro-naphtho[2,3-b]furan-2-one | 5.18 | 0.03 |
Tyramine, N-aminoacetyl- | ||
Butanoic acid, 3-hydroxy-3-methyl- | 6.74 | 0.04 |
Acetic acid, hydrazide | 6.95 | 0.01 |
Propanoic acid, 2,2-dimethyl-, hydrazide | 7.11 | 0.01 |
Disulfide, propyl 1-(propylthio)ethyl | 9.61 | 0.06 |
Oxalic acid, ethyl propyl ester | 11.13 | 0.02 |
4-Penten-2-one | 14.83 | 0.01 |
Nitroxide, bis(1,1-dimethylethyl) | 15.38 | 0.01 |
Pent-2-ynal, 4,4-dimethyl- | 25.30 | 0.01 |
1,3,7-Octatriene, 3,7-dimethyl- | 25.41 | 0.01 |
2-Butanol, (ñ)- | 27.32 | 0.03 |
2,5-Diethylphenol | 31.06 | 0.03 |
Benzenemethanol, 4-(1-methylethyl)- | 31.42 | 0.01 |
1,5-Decadiyne | 32.54 | 0.01 |
1,2-Benzenedicarboxylic acid, mono(2-ethylhexyl) ester | 44.10 | 0.08 |
Octadecane, 6-methyl- | 45.59 | 0.01 |
n-Hexadecanoic acid | 47.39 | 0.01 |
3,7,11,15-Tetramethylhexadeca-1,3,6,10,14-pentaene | 47.70 | 0.01 |
7,11,15-Trimethyl-3-methylene-hexadeca-1,6,10,14-tetraene | 47.86 | 0.01 |
1H-2,8a-Methanocyclopenta[a]cyclopropa[e]cyclodecen-11-one, 1a,2,5,5a,6,9,10,10a-octahydro-5,5a,6-trihydroxy-1,4-bis(hydroxymethyl)-1,7,9-trimethyl-, [1S-(1à,1aà,2à,5á,5aá,6á,8aà,9à,10aà)]- | 50.89 | 0.01 |
5-Benzofuranacetic acid, 6-ethenyl-2,4,5,6,7,7a-hexahydro-3,6-dimethyl-à-methylene-2-oxo-, methyl ester | 51.73 | 0.01 |
Heptadecane, 2,3-dimethyl- | 55.67 | 0.04 |
RT: retention time; RA: relative abundance. 22–29Organic compounds corresponding to peak numbers on the chromatogram referring to effluent C in Figure
Total ion chromatograms of extracts of textile effluents A from the studied site. Peak numbers correspond to the chemical compounds indicated in Table
Total ion chromatograms of extracts of textile effluent B from the studied site. Peak numbers correspond to the chemical compounds indicated in Table
Total ion chromatograms of extracts of textile effluents C from the studied site. Peak numbers correspond to the chemical compounds indicated in Table
Fast characterization of the identified compounds revealed the presence of organic pollutants belonging to a wide range of chemical classes such as aromatic carboxylic acids, alkanes, benzoic compounds, phthalates, aliphatic carboxylic acids, aromatic amines, and linear aliphatic alcohols (Tables
Aromatic carboxylic acids present in textile effluents are reported to be constituents of natural tanning agents and dyes [
Other compounds were also present in the studied wastewater such as linear aliphatic alcohols (e.g., ethyl alcohol and acetol; Table
Concerning textile effluent B, we note the predominance of two toxic compounds: phtalimide dioxime acetamide (RA = 30.45%, peak 13 in Figure
This complex effluent also contains aromatic carboxylic acids (acid, 2,4-bis[(trimethylsilyl)oxy]-, trimethylsilyl ester (peak 17, Figure
As described in Table
Aromatic amines 2-amino-4-hydroxy-6-p-cyanophenylpropylpteridine and 3-amino-3-(2,4-dichloro-phenyl)-propionic acid are the dominant ones with RA of 32.81 and 11.59%, respectively (peaks 26 and 27, Figure
Azo dyes are recalcitrant, non-biodegradable, and persistent among all chemical classes of dyes. Aromatic amines detected in the studied effluents are the result of the reduction of the azo bond of azo dyes. The first concerns with human exposure to carcinogenic aromatic amines arose in the dye manufacturing industry as early as the late nineteenth century [
Since the 1890s, the increase in bladder cancer has been observed among employees working in the dyeing department of textile industry, which is related to their exposition to aromatic amines [
As described in this paper, benzoic derivatives are indicative compounds of textile effluents. Effluent C contains considerable amounts of these compounds; benzene, 1-(2,2-dimethoxyethyl)-4-methoxy (RA = 12.48%) and benzene, (1,2-dimethoxyethyl)-(RA = 6.03%) are major benzoic compounds in this effluent (peaks 24 and 25, Figure
Aromatic amines detected in the studied effluents are originating from dyes and pigments and are known to be potential hazards to human health and the environment [
Different effluents from a textile industry of Fez city, Morocco, were collected and analyzed to determine the impact of textile industry on water pollution and human health. The water quality parameters like BOD5, COD, TSS, and TDS of textile effluents were found to be significantly higher than the maximum permissible limit prescribed by M.D.Q.S and WHO. The results of this study clearly show that textile industry in Fez city, Morocco, is polluting the local aquatic environment. However, the numerous by-products of textile industry characterized in this study like benzoic acid, 2,3-dimethyl-6-(3-methyl-1-oxobutyl); 2-amino-4-hydroxy-6-p-cyanophenylpropylpteridine; phenol, 4-[2-[2-(chloromethyl)-1,3 dioxolan-2-yl]ethyl]; benzene, 1-chloro-2-diethoxymethyl; and naphtho [2,3-d]-1,3-dioxol-5-ol, 3a,4,9,9a-tetrahydro-2,2-dimethyl-, cis, which are potentially toxic, can be used as typical indicators of textile contaminants in polluted aquatic systems. These compounds have a significant health hazard as it has been shown in a multitude of ecotoxicological studies on industrial effluents. The present research highlighted the diversity of organic compounds present in textile effluents. We discussed the toxicity of some organic compounds from the GC/MS analysis results (listed in Tables
The data used to support the findings of this study are included within the article.
The authors declare that there are no conflicts of interest.
This study was supported by the Faculty of Sciences Dhar el Mahrez, Fez, Morocco.