Toxicity assessment of treated effluents from a textile industry in Lagos, Nigeria

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1 Africn Journl of Environmentl Science nd Technology Vol. 6(11), pp , Novemer 2012 Aville online t DOI: /AJEST ISSN Acdemic Journls Full Length Reserch Pper Toxicity ssessment of treted effluents from textile industry in Lgos, Nigeri Odjeg V. J.* nd Bmgose N. M. Deprtment of Botny, University of Lgos, Akok, Lgos, Nigeri. Accepted 2 July, 2012 Wter pollution cused y industril effluent dischrges hs ecome worrisome phenomenon due to its impct on environmentl helth nd sfety. Textile industries contriute immensely to surfce wter deteriortion nd re ctegorized mong the most polluting in ll industril sectors. For this reson, the toxicity of treted textile effluent ws ssessed in Celossi rgente y exposing them to effluentpolluted surfce wter from Ieshe River. In the present study, prmeters investigted includes, growth, photosynthetic pigment content, lipid peroxidtion, nd metl ccumultion. The results showed tht treted textile effluent from Nichemtex Compny, ffected the growth, dry iomss, root development nd photosynthetic pigment content of C. rgente. The treted effluent cused 41% growth inhiition while the totl chlorophyll decresed y 59.87% in reltion to the control plnts. Furthermore, it lso elevted the levels of lipid peroxidtion nd hevy metls in the plnt. It ws therefore implicted tht treted textile effluent entering Ieshe River could cuse toxic effects on orgnisms. It ws emphsized tht using the wter for irrigtion nd s portle wter in its present stte is unsfe. Key words: Textile effluent, toxicity, surfce wters, growth inhiition, Celosi rgente. INTRODUCTION Industril effluents re undesirle y-products of economic development nd technologicl dvncement. When improperly disposed off, they imperil humn helth nd the environment. Effluents from textile industries re complex mixtures of chemicls vrying in quntity nd qulity. These industries cn generte oth inorgnic nd orgnic wste mixed with wste wters from the production processes, which leds to chnge in oth iologicl nd chemicl prmeters of the receiving wter odies (Gomez et l., 2008). Conventionl wter qulity prmeters such s chemicl oxygen demnd nd suspended solids my not detect toxic compounds present in vriety of industril wstewters nd treted wstes, nd chemicl procedures lone cnnot provide sufficient informtion on the potentil hrmful effects of chemicls on the environment (Scn nd Blcioglu, 2006). Sometimes, *Corresponding uthor. E-mil: odjesvic@yhoo.com. Tel: the treted effluent does not exceed the dischrge limits ut the results of toxicity tests show potentil toxicity (Lin et l., 1994). It hs een estlished tht some chemicls re not totlly removed ecuse the conventionl technology of tretment used in wstewter tretment plnts seems to e insufficient for the complete removl of these compounds (Ternes, 1998). Thus, the toxic effects of sustnces in complex mixtures like textile effluents cn e est evluted through toxicity testing. The key environmentl issues ssocited with textile industry re wter use, tretment nd disposl of queous effluent. As in the cse of Nichemtex Compny in Ikorodu, the treted effluents re eing dischrged through dringe chnnels into the Ieshe strem which susequently ffects the wter qulity of the strem. Depending on the dosge nd exposure period, the effluents could e poisonous to plnts, qutic life nd humns. In mny developed countries, toxicity tests on industril effluents re required to ensure tht such dischrges will not hve dverse effects on the environment (Whitehouse nd Dijk, 1996). In Nigeri, environmentl

2 Odjeg nd Bmgose 439 regultions on pollution control of industril dischrges nd other pollutnts re enforced y the Federl Environmentl Protection Agency (FEPA) which relies on conventionl physicochemicl procedures. Lgos is highly populted nd there re quite numer of industries distriuted cross the city, development tht hs put the city under serious pressure in terms of environmentl sfety. Consequently, the city nd its environs hve witnessed environmentl degrdtion leding to decresed iodiversity nd extinction of mny sensitive orgnisms. Most of the industries in Lgos Stte do not control their wstewter effluents y processing, wste recycling or end-of-pipe tretment. Thus, effluents with some levels of toxic sustnces re eing dischrged into the environment. Pollution of nturl wters with wste effluents rising from vrious industries hs ecome serious prolem in Lgos, s industril growth nd development hve een on the increse. In Ikorodu xis of Lgos, textile mills represent n importnt economic sector. Nichemtex is fmous textile industry locted in Ikorodu, Lgos nd is well known for the production of textile mterils in lrge quntities. Due to the nture of its opertions which requires lrge volume of wter, most of the wstewter generted ends up in the nery Ieshe strem therey ltering its nturl stte s regrd qulity. The ecologicl nd toxicologicl prolems resulting from the dischrge of wstewters from this industry into dringe tht ends up in Ieshe strem hs een the most importnt wter pollution prolems in this re. This prolem is further ggrvted ecuse some residents in Ikorodu depends directly on this strem s source of wter oth for drinking nd other domestic purposes. In ddition, locl frmers prticulrly, vegetle growers, use the wter from this strem directly for irrigtion purposes. Consequently, there is likelihood tht toxicnts from this wstewter my ffect plnts, enter the food chin nd ffect lrger humn popultion. Thus, this work ims to evlute the toxicity of treted effluent of textile industry using Celosi rgente s model plnt. The plnt is populr lefy vegetle consumed lrgely y the people in Lgos, Nigeri. MATERIALS AND METHODS Smple collection nd tretment Wter smples were collected from two sites in Ieshe strem, Ikorodu, Lgos into clen plstic continers. Site 1 ws the point where the effluent flows into the strem while site 2 which served s the control ws 100 m upstrem from the dischrge point. The wter smple ws immeditely evluted in its crude nturl stte for physicochemicl vriles. Seeds of C. rgente were otined from Institute of Agriculturl Reserch nd Trining (IAR&T), Idn, Nigeri in single tch nd enough for the study. Seeds were plnted on sndy-lom nursery ed (1.5 m 7 m) t the University of Lgos Botnic grden. The nursery ed ws kept moist y dding wter when necessry. Seedlings were llowed to grow on the nursery for 3 weeks fter germintion to enle them ttin n pprecile height rnge of 6 to 8 cm. Seedlings of uniform height (7 cm) were selected nd trnsplnted into plstic uckets contining sndylom soil. Four seedlings were plnted in ech ucket nd ech individul seedling ws oserved. The uckets contining the seedlings were then plced in greenhouse nd treted with 1 L effluent wter smple every 3 dys up to 3 weeks while the control plnts received equl mount of wter devoid of effluent. At the end of the tretment period, plnts were hrvested nd vrious prmeters were evluted. All nlyses were replicted 4 times unless otherwise stted. Root growth mesurement Uprooted plnts were thoroughly wshed with clen wter nd the min root length ws mesured. Also, root rchitecture ws visully exmined. Dry weight determintion Hrvested plnts were wshed thoroughly in running tp wter to remove soil prticles. After rinsing with distilled wter, they were plced in leled pper gs nd oven dried t 80 C for 72 h. The dried smples were weighed using digitl top loding weighing lnce (Mettler AE 100) to determine the dry weight. Growth inhiition ws then clculted in reltion to the control men: % inhiition = Determintion of totl chlorophyll λtreted λcontrol For the determintion of pigment vrition due to textile effluent tretment, only the leves were used. Plnt leves (150 mg) were ground in 15 ml 80% cetone in the drk. After centrifugtion t 4000 g for 5 min, the sornce of the superntnt ws red t 645 nd 663 nm (Arnon, 1949). The totl chlorophyll content ws clculted using the formul given y Mchlchln nd Zlik (1963). Lipid peroxidtion Lipid peroxidtion ws mesured y estimtion of the mlondildehyde (MDA) content following modified procedure of Wng nd Jin (2005). Fresh leves (300 mg) were homogenized in 3 ml 20% trichlorocetic cid (TCA). The homogente ws centrifuged t g for 5 min. The superntnt (1 ml) ws mixed with equl volume of 0.6% (w/v) thiorituric cid solution comprising 10% TCA. The mixture ws incuted for 30 min in oiling wter th nd cooled quickly on ice th. The sornce of the mixture ws red t 450, 532 nd 600 nm. The concentrtion of MDA ws clculted s 6.45 (A 532-A 600)-0.56 A 450. Metl content in leves Aout 2 g of the dried smples were weighed individully into porcelin dish nd shed in furnce t 550 C. The shed smple ws trnsferred into qurtz digestion vessel nd 20 ml of conc. HNO 3 ws dded nd heted to ner dryness. It ws refluxed with 15 ml of 20% HNO 3. After cooling, the digest ws filtered through

3 440 Afr. J. Environ. Sci. Technol. Tle 1. Chrcteriztion of the wter smple from Ieshe River polluted with treted effluent from textile industry in Lgos compred with FEPA stndrds. S/N Prmeters Men levels detected FEPA stndrds 1 ph Turidity (FTU) Conductivity (µs/cm) TDS TSS Cl SO NO NH CN PO BOD COD Cu Zn P Cr Ni All units re in mg/l, except for ph nd where noted otherwise. Whtmn No. 1 filter pper into 25 ml volumetric flsk nd djusted to volume with 2% HNO 3. Metl concentrtions were determined using Atomic Asorption Spectrophotometer (AAS). Sttisticl nlysis The experiment ws set up with rndomized lock design. The dt were expressed s men vlues with stndrd error (SE). One-wy nlysis of vrince (ANOVA) ws used to ssess the significnce of the effects of the treted effluent on the plnt. Sttisticl nlysis ws performed with the SPSS 15.0 softwre pckge nd p vlues < 0.05 were considered significnt. RESULTS Physicochemicl chrcteristics of the wter smple The results of physicochemicl vriles of the wter smple re s shown in Tle 1 together with the limit vlues ccepted y the regultory uthority in Nigeri. The wter smple s BOD 5, Cu nd Zn levels were found to e higher thn the reference stndrds, hence violting the dischrge limits. The iochemicl oxygen demnd (BOD 5 ) ws mg/l; copper, mg/l; nd zinc, mg/l. Growth The effects of the treted textile effluent on the root growth of C. rgente re shown in Figure 1 nd Figure 2. The root growth of C. rgente ws mrkedly ffected y the textile treted effluent. At the end of the experiment period, the control plnts exhiited primry root length of 6.43 ± 0.46 cm while the treted plnts hd men vlue of 4.36 ± 0.25 cm, difference tht ws significnt t p< In the sme vein, there ws distinct difference in the root rchitecture etween the control plnts nd those tht received treted effluents. The roots of the control plnts ppered thicker with more numerous lterl roots compred to the treted plnts (Figure 2). The dry weight dt clerly showed tht treted effluent hd significnt inhiitory effects on C. rgente s the treted plnts ccumulted less iomss compred to the control plnts (Figures 3 nd 4). The treted effluent cused 41% growth inhiition in C. rgente reltive to the control plnts. Effect on chlorophyll contents Treted textile effluent showed significnt inhiitory effect on the totl chlorophyll content in C. rgente (Figure 5). The totl chlorophyll in the treted plnts decresed y 59.87% in reltion to the control plnts. Lipid peroxidtion To determine the memrne dmge cused y the treted textile effluent, the MDA content ws evluted in leves of C. rgente. At the end of the experiment, it

4 Odjeg nd Bmgose 441 Figure 1. Effects of treted textile effluent on the root length of Celosi rgente. All the vlues re the men of four replictes ± SE. ANOVA significnt t p < Columns with different letters re significntly different. A B Figure 2. Differences in root rchitecture of Celosi rgente etween the control (A) nd the treted (B). ws oserved tht exposure treted textile effluent significntly ffected the MDA content (Figure 6). It ws determined tht C. rgente exposed to treted textile effluent hd higher MDA content, s compred to the control. A men vlue of 9.63 ± 0.37 µmol g -1 f.wt ws oserved in plnts tht received the treted textile effluent, s compred to 5.86 ± 0.48 µmol g -1 f.wt oserved in the control.

5 442 Afr. J. Environ. Sci. Technol. Figure 3. Effects of treted textile effluent on the dry weight of Celosi rgente. The vlues re the men of four replictes ± SE. ANOVA significnt t p < Columns with different letters re significntly different. Figure 4. Growth inhiition (%) of Celosi rgente exposed to treted textile effluent. The vlues re the men of four replictes ± SE. ANOVA significnt t p < Columns with different letters re significntly different. Metl ccumultion The concentrtions of Cu nd Zn in plnt tissues significntly incresed following exposure to treted textile effluent. The treted plnts showed elevted levels of Cu nd Zn which were ± nd ± µg g -1 d wt, respectively, compred to the control plnts which respectively hd 0.01 ± nd ±

6 Odjeg nd Bmgose 443 Figure 5. Effects of treted textile effluent on the totl chlorophyll in the leves of Celosi rgente. All the vlues re the men of four replictes ± SE. ANOVA significnt t p < Columns with different letters re significntly different. Figure 6. Mlondildehyde (MDA) content in leves of Celosi rgente exposed to treted textile effluent. The vlues re the men of four replictes ± SE. ANOVA significnt t p < Columns with different letters re significntly different µg g -1 d wt (Figure 7). DISCUSSION The present study demonstrtes tht treted textile effluent wter smple ffected growth, iomss, photosynthetic pigment, nd memrne integrity of C. rgente. The results implied tht treted textile effluent in Ieshe River might cuse io-toxicity on orgnisms. Growth inhiitory nd low chlorophyll content in plnts hs een reported in seprte studies involving Triticum

7 444 Afr. J. Environ. Sci. Technol. Figure 7. Copper nd zinc content in leves of Celosi rgente exposed to treted textile effluent. The vlues re the men of four replictes ± SE. ANOVA significnt t p < Columns with different letters re significntly different. estivum (Khn nd Jin, 1995) nd Ze mys (Pndey et l., 2008). These effects could e s result of high slt content (Luchli nd Luttge, 2000) nd presence of hevy metls in the treted textile effluent (Kt- Pendis nd Pendis, 1992). For clrity, we nlyzed the properties of the treted effluent polluted river wter. It ws found tht the wter smple contined high concentrtions of CN -, Cu nd Zn while the TSS nd BOD 5 were fr ove the recommended stndrds. An importnt feture of metl-induced environmentl stress is the ctivtion of common mechnism involving the production of Rective Oxygen Species (ROS) in cells of the ffected orgnism (Shi nd Zhu, 2008; Mishr nd Choudhuri, 1999; Wng et l., 2004). Since memrne lipid is one of the preferred trgets of ROS in plnt under environmentl stress, it is considered to e relile indictor of controlled modultion of ROS levels nd oxidtive stress (Hlliwell nd Gutteridge, 1999). We investigted the levels of lipid peroxidtion y mesuring MDA in the leves. Celosi rgente exposed to treted textile wter smple showed significntly high level of MDA. This mens tht pollutnts from the treted textile effluent ws ccumulted y the plnts which induced the genertion of excessive ROS, thus, the plnt experienced sustntil oxidtive stress. These dt re in greement with the results from Bruguier gymnorrhiz (Zhng et l., 2007) nd Oryz stiv (Verm nd Duey, 2003). Studies of surfce wter contmintion re of immense importnce ecuse these wters re used for griculturl nd domestic purposes. The present study hs shown tht surfce wters, into which treted industril effluents re directly dischrged, re not sfe for use in griculture nd other household domestic purposes. Conclusion The dt otined from this study indicted tht the treted effluents from the textile industry tht re directly dischrged into the Ieshe River contin toxic compounds. These compounds contminte the surfce wter, therey mking it unfit for irrigtion nd drinking. Therefore, proper tretment of effluent wter nd enforcement of pollution control y the regultory uthority on the indiscriminte dischrge of textile wstewter into wter odies should e crried out. Since frmers re using wter from Ieshe River for griculturl purposes nd the residents of the town re using oth the surfce nd underground wters from the sme re s potle wter, it is quite unsfe for this dischrge into this wter ody to continue. The ecologicl nd humn helth sfety of continul dischrge of this treted textile effluents into this river re undoutedly under thret. The present study lso emphsized the importnce of plnts in toxicity ssy. It cn e used to complement other ecologicl, toxicologicl, nd conventionl chemicl

8 Odjeg nd Bmgose 445 tests nd for estlishing priorities of pollution control. The uthors therefore recommend proper tretment of wste wters efore dischrge into Ieshe River, nd lso, occsionl physicochemicl nlyses of the river wter re necessry. ACKNOWLEDGEMENTS The uthors re thnkful to Mr Begus of Chemistry Deprtment, University of Lgos, for his technicl support. The professionl dvice of Dr Croline Umeese of Botny Deprtment, University of Lgos, is pprecited. REFERENCES Arnon DI (1949). Copper enzymes in isolted chloroplst, polyphenol oxidse in Bet vulgris. Plnt Physiol. 24:1-15. Gomez N, Sierr MV, Cortelezzi A, Rodrigues Cpitulo A (2008). Effects of dischrges from the textile industry on the iotic integrity of enthic ssemlges. Ecotoxicol. Environ. Sf. 69: Hlliwell B, Gutteridge JMC (1999). Free Rdicls in Biology nd Medicine 3rd ed. Oxford Science Pulictions, New York. 936 pp. Kt-Pendis A, Pendis H (1992). Trce Elements in Soils nd Plnts. 2 nd ed., CRC Press, Boc Rton, Florid. Khn TI, Jin V (1995). Effect of textile industry wste wter on the growth nd some iochemicl prmeters on Triticum estivum. J. Environ. Pollut. 2: Luchli A, Luttge U (2000). Slinity-Environment-Plnts- Molecules. Kluwer Acdemic Pulishers, Netherlnds. Lin CF, Ho OJ, Jeng FT (1994). Microtox evlution of industril wstewters. Wter Sci. Technol. 30: Mclchln S, Zlik S (1963). Plstid structure, chlorophyll concentrtion nd free mino-cid composition of chlorophyll mutnt of rley. Cn. J. Bot. 41: Mishr A, Choudhuri, MA (1999). Effects of slicylic cid on hevy metl-induced memrne deteriortion medited y lipoxygense in rice. Biol. Plntrum 42: Pndey SN, Nutiyl BD, Shrm CP (2008). Pollution level in distillery effluent nd its phytotoxic effect on seed germintion nd erly growth of mize nd rice. J. Environ. Biol. 29: Scn MT, Blcioglu IA (2006). A cse study on lgl response to rw nd treted effluents from n luminum plting plnt nd phrmceuticl plnt. Ecotoxicol. Environ. Sf. 64: Shi Q, Zhu Z (2008). Effects of exogenous slicylic cid on mngnese toxicity, element contents nd ntioxidtive system in cucumer. Environ. Exp. Bot. 63: Ternes TA (1998). Occurrence of drugs in Germn sewge tretment plnts nd rivers. Wter Res. 32: Verm S, Duey RS (2003). Led toxicity induces lipid peroxidtion nd lters the ctivities of ntioxidnt enzymes in growing rice plnts. Plnt Sci. 164: Wng H, Jin JY (2005). Photosynthetic rte, chlorophyll fluorescence prmeters, nd lipid peroxidtion of mize leves s ffected y zinc deficiency. Photosynthetic 43: Wng YS, Wng J, Yng ZM, Wng QY, Li B, Li SQ, Lu YP, Wng SH, Sun X (2004). Slicylic cid modultes luminum-induced oxidtive stress in roots of Cssi tor. Act Bot. Sin. 46: Whitehouse P, Dijk P (1996). The precision of qutic toxicity tests: the implictions for the control of effluents y direct toxicity ssessment. In: Tpp JF, Whrfe JR, Hunt SM (eds), Toxic Impcts of Wstes on the Aqutic Environment. Cmridge. Zhng F, Wng Z, Dong J (2007). Effect of hevy metl stress on ntioxidtive enzymes nd lipid peroxidtion in leves nd roots of two mngrove plnt seedlings (Kndeli cndel nd Bruguir gymnorrhiz). Chemosphere. 67: