Research Article

Ecological Risk Assessment of Heavy Metals in Cassava Mill Effluents Contaminated Soil in a Rural Community in the Niger Delta Region of Nigeria  

Sylvester Chibueze Izah , Sunday Etim Bassey , Elijah Ige Ohimain
Department of Biological Sciences, Faculty of Science, Niger Delta University, Wilberforce Island, Bayelsa State, Nigeria
Author    Correspondence author
Molecular Soil Biology, 2018, Vol. 9, No. 1   doi: 10.5376/msb.2018.09.0001
Received: 25 Oct., 2017    Accepted: 20 Dec., 2017    Published: 05 Jan., 2018
© 2018 BioPublisher Publishing Platform
This is an open access article published under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.
Preferred citation for this article:

Izah S.C., Bassey S.E., and Ohimain E.I., 2018, Ecological risk assessment of heavy metals in cassava mill effluents contaminated soil in a rural community in the Niger Delta Region of Nigeria, Molecular Soil Biology, 9(1): 1-11 (doi: 10.5376/msb.2018.09.0001)

Abstract

This study evaluated the ecological risk assessment of heavy metals in cassava mill effluents contaminated soil in rural community in the Niger Delta region of Nigeria. Secondary data was used for the ecological risk assessment. Two background scenarios i.e. geometric mean (BGM) and median mean (BMM) was used as the reference value. The heavy metals that were assessed for ecological risk include viz: Cr, Zn, Cu, Co, Ni, Mn, Pb and Cd. 50% of mean detected individual heavy metals were considered for the location that was not detected. Assessment of the ecological risk was carried out following well established protocol. The results of the potential ecological risk (ER), Ecological risk index (ERI) and Monomial potential ecological risk (MPER) of heavy metals showed low risk under both scenarios except for Cd in one of the locations that showed moderate risk for MPER under both background scenarios in wet season. The distribution of the heavy metals based on potential ecological risk were in the order; Cd > Ni > = Pb > Co > Cu> Cr > Mn = Zn (BMM) and Cd > Pb > Ni = Co > Cu = Cr > Mn > Zn (BGM) for wet season and Cd > Pb = Ni = Cu > Co > Cr > Mn = Zn (BMM) and Cd > Pb > Cu = Co > Ni > Cr > Mn = Zn for dry season. The study showed low ecological risk associated with cassava mill discharged into the environment. cassava mill effluents on soil

Keywords
Cassava mill effluents; Contamination factor; Ecological risk index; Heavy metals

Background

Nigeria is the leading cassava producing country in the world, accounting for about 20% of total global production (Ohimain et al., 2013; Izah and Ohimain, 2015; Izah, 2016; Izah et al., 2017a; b; c; d; e; f). Cassava cultivation and processing is a major source of livelihood to several families in the southern Nigeria especially in the rural communities (Izah and Aigberua, 2017; Izah et al., 2017a; b; c; d). Cassava is processed by three scales of processor in Nigeria viz: smallholder, semi-mechanized and mechanized processing. But the small-scale processors have dominated the enterprise especially in the Niger Delta region of Nigeria. Rudimentary equipment is mostly used for processing of cassava tuber into gari, lafun and fufu.

 

During cassava processing, wastes are generated in different zones including peels from the peelings stage, cassava mill effluents from the dewatering/pressing zone and gaseous emissions from the frying stage (Ohimain et al., 2013). The liquid waste popularly known as cassava mill effluents is generated in the grating and dewatering zone and it account for about 16% of total weight of cassava tuber (Ohimain et al., 2013). The wastes are discharged into the environment without any form of treatment (Izah et al., 2017a; b). Thereby impacting on the characteristics of the receiving soil with regard to microbial, physicochemical cation and anions exchange, soil particle size, bulk density and porosity, heavy metals among others (Nwaugo et al., 2007, 2008; Ehiagbonare et al., 2009; Eneje and Ifenkwe, 2012; Nwakaudu et al., 2012; Osakwe, 2012; Okechi et al., 2012; Chinyere et al., 2013; Izonfuo et al., 2013; Omotiama et al., 2013; Ezeigbo et al., 2014; Ibe et al., 2014; Eze and Onyilide, 2015; Igbinosa, 2015; Igbinosa and Igiehon, 2015; Izah et al., 2017a; b; c; d; e; g; Omomowo et al., 2015).

 

One of the major constituent of the soil majorly impacted by wastes is heavy metals composition. Heavy metals concentration in soil is usually highest top most regions (Chen et al., 1997; Wei and Yang, 2010; Acosta et al., 2015; Mazurek et al., 2017) where the greatest bonding occurs (Parzych et al., 2012; Gu et al., 2016; Mazurek et al., 2017). Heavy metals are typically toxic when their concentration exceeds permissible level specified by appropriate agency in the biological system for the essential metals. While non-essential metals such as cadmium, mercury, lead, arsenic is highly toxic even at low concentration. Both essential and non-essential heavy metals have been detected in soil receiving cassava mill effluents (Nwakaudu et al., 2012; Osakwe, 2012; Igbinosa, 2015; Igbinosa and Igiehon, 2015; Izah et al., 2017c).

 

Authors have reported that heavy metals have density that is 5 times higher than the density of water (Idris et al., 2013; Hassaan et al., 2016; Izah and Angaye, 2016; Izah et al., 2016, 2017g). Their application in several domestic, industrial, agricultural and technological activities by humans have led to their increased distribution in the environment (Hassaan et al., 2016). Presently heavy metal is a major source of concern to human health and environment (Hassaan et al., 2016). This could be due to the toxic effect they pose in biological organisms and food chain. According to Hassaan et al. (2016), the toxicity of heavy metals relies on numerous criteria such as dose, method of exposure, and chemical constituent. In human system, it could cause several diseases which have been comprehensively documented by Izah et al. (2016, 2017h), Izah and Angaye (2016), Muhammad et al. (2014).

 

Again, industrialization, urbanization, developmental works and other anthropogenic activities are also having adverse impacts on the soil environment (Qiu, 2010). The soil plays several ecological, social purposes to human and other biodiversity (Izah et al., 2017c). Therefore, the occurrence of heavy metals in the soil especially the topmost part is one of the major concerns of environmentalists and public health practitioners (Mohseni-Bandpei et al., 2016).

 

In this regard, several environmental risk indices are used to assess the nature of the soil due to anthropogenic activities releasing heavy metals into the environment. Typically, ecological risk assessment associated with pollutant in the biophysical components of the environment (soil, air and aquatic ecosystems) and other environmental factors (such as chemical, physicochemical, biological, and eco-toxicological parameters) are often considered during environmental risk assessment (Fiori et al., 2013). The ecological importance of heavy metals in soil has attracted attention because of its close relation to human health especially in rural areas. One of the major parameters studied is the geochemical distributions of the environment (Jiang et al., 2014; Sofianska and Michailidis, 2016) including ground water (Bhutiani et al., 2017) and sediments (Hakanson, 1980; Zhu et al., 2012; Fiori et al., 2013; Ghaleno et al., 2015; Soliman et al., 2015; Todorova et al., 2016; El-Metwally et al., 2017) and soil (Yang et al., 2011; Al-Anbari et al., 2015). Therefore, risk assessment of heavy metals in the environment provides theory support for risk management (Zhu et al., 2012). Among the indices used in assessing risk assessment is contamination factor and potential ecological risk index (Mohseni-Bandpei et al., 2016) and they have widely applied in soil, sediment and water studies (Kowalska et al., 2016; Mazurek et al., 2017; Bhutiani et al., 2017).

 

Therefore this study focused on the ecological risk assessment of heavy metals in cassava mill effluent contaminated soil in rural community in the Niger Delta region of Nigeria with emphasis on the ecological risk (ER) and ecological risk index (R’). The findings of the study will useful to environmentalist and policy makers.

 

1 Materials and Methods

1.1 Study area

Ndemili lies between latitude N06º01’ and longitude E006º17’. Ndemili is one located in Ndokwa-West local government area of Delta state. Like other region of the state. It’s characterized by 28±6ºC and 50–95% of temperature and relative humidity respectively among both seasons (wet and dry) of the year. The average annual rainfall of 1900mm which is peculiar to other areas in Delta state (Orji and Egboka, 2015). Two predominant seasons include wet season (7 months-April to October) and dry season (5 months-November to March of the following year). But in recent times, it appears that season’s especially wet season beginning to shift from the conventional known period in the Niger Delta region of Nigeria. Farming of cassava, yam, maize, oil palm etc. is a major occupation of the indigenous people of the area (Izah et al., 2017c; e; g).

 

1.2 Data source

Secondary data was used for the assessment of the ecological risk of heavy metals in cassava mill effluents contaminated soil. Authors have recommended the use of geometric mean (Thambavani and Uma Mageswari, 2013; Bhutiani et al., 2017) and median mean (Monakhov et al., 2015; Bhutiani et al., 2017) as background values in assessment of environmental risk and it have been applied by Izah et al. (2017c; e; g). Hence, the background values including geometric mean (BGM) and median mean (BMM) was adopted in this study for the assessment of heavy metals level in 5 locations from cassava mill effluents contaminated soil analyzed in two predominant seasons (wet and dry) as reported by Izah et al. (2017c) (Table 1). Also contamination factor values previously reported by Izah et al. (2017e) (Table 2) was used for the study. The heavy metals considered in the study include Cr, Zn, Cu, Co, Ni, Mn, Pb and Cd.

 

 

Table 1 Concentration of heavy metals among the various locations with their respective background values 

Note: Izah et al. (2017c); BMM-Background median mean; BGM-Background geometric mean

 

 

Table 2 Contamination factor of heavy metals concentration in cassava mills effluent contaminated soil

Note: CF < 1 (low contamination); 1 ≤ CF <3 (moderate contamination); 3 ≤ CF < 6 (considerable contamination); CF ≥ 6 (very high contamination); Source: Izah et al. (2017e); BMM-Background median mean; BGM-Background geometric mean

 

1.3 Ecological risk index

Ecological risk index (ERI) is used to assess the ecological risk level of heavy metals in the environment (Hakanson 1980; Bhutiani et al., 2017) that could be toxic to biota (Yisa et al. 2012; Bhutiani et al., 2017). The Potential ecological risk (ER) is the index for individual metals, while the summation of ER is often expressed as R’ (Singovszka et al., 2014). Based on the values presented in Table 1 and Table 2, the resultant ecological risk index was calculated and the result was compared to the criteria presented in Table 3. The formula for the calculation of both ER and R’ has been previously presented by Hakanson (1980) and have been widely applied by Bhutiani et al. (2017), Singovszka et al. (2014), Soliman et al. (2015), Ghaleno et al. (2015), Todorova et al. (2016), Fiori et al. (2013), Karydas et al. (2015), Zhu et al. (2012), Qingjie et al. (2008), Elias et al. (2014), Qiu (2010), Mohseni-Bandpei et al. (2016), Swarnalatha et al. (2013), Tang et al. (2014), Vowotor et al. (2014), Mazurek et al. (2017), Kowalska et al. (2016), Gasiorek et al. (2017).

 

 

Table 3 Ecological risk index used to assess environmental pollution of cassava mill effluents contaminated soil

Note: ER and R’ was developed by Hakanson (1980) and have been widely applied by Bhutiani et al. (2017), Singovszka et al. (2014), Soliman et al. (2015), Todorova et al. (2016), Fiori et al. (2013), Karydas et al. (2015), Zhu et al. (2012), While MPER was modified from Hakanson (1980) by Guan et al. (2014)

 

 

Where Tr is the toxic response factor viz: Cr = 2, Pb = Cu = 5, Cd = 30 and Zn = 1 (Hakanson, 1980), Ni = 5 (Xu et al., 2008; Soliman et al., 2015; Bhutiani et al., 2017), Co = 5 (Swarnalatha et al., 2013) and Mn = 1 (Xu et al., 2008; Soliman et al., 2015) and CF represents the contamination factor (Table 2).

 

 

Modified (Monomial) potential ecological risk

Monomial potential ecological risk (MPER) is one of the modified risk indices used to assess and or/ identify sensitivity of the heavy metal contamination in an environment i.e. soil. MPER is calculated by summing up products of the concentration of all the heavy metal and their respective toxic factor and divided by the background values. MPER have been calculated by Guan et al. (2014) as:

 

 

Where T = Toxic factor; C = Concentration of individual metals; Bm = Background values

 

2 Results and Discussion

The potential ecological risk (ER) used to assess heavy metals in cassava mill contaminated soil is presented in Table 4. The risk index ranged from low (ER < 40) to moderate (Er 40 ≤ Er < 80). In all the eight heavy metals assessed, the risk level was low in all the locations across both seasons except for cadmium. Cadmium concentration in wet season of both background considerations (BMM and BGM) was moderate. Furthermore, cadmium concentrations for wet season of LA under BGM scenario were also moderate. The high moderate risk of cadmium in wet season of some locations could be due to impact of runoff after rainfall and or/ other human activities in the mills. The values reported in this study had some similarity with the work of Soliman et al. (2015) who reported uncontaminated sediment from Mediterranean coast of Egypt by lead, zinc and copper. Again the higher cadmium concentration in the ecological risk is comparable to the findings of Fiori et al. (2013) on aquatic pollution control in coastal water bodies from Rio de Janeiro state, Brazil. Zhu et al. (2012) reported that cadmium has higher ecological risk compared to other metals. The higher ecological risk of cadmium could be due to the higher toxic factor (Zhu et al., 2012; Ghaleno et al., 2015). The trend of cadmium having higher ecological risk is also comparable to the work of Todorova et al. (2016) that reported heavy metals in sediment of a small hydropower cascade in the order; mercury > cadmium > arsenic ~ copper > lead > zinc. Cadmium which has no known biological function is relatively higher and it’s toxic to biodiversity including plants, animals even at low concentration (Ghaleno et al., 2015; Izah et al., 2016). Furthermore, Zhang and Shan (2008), Ghaleno et al. (2015), Sayadi et al. (2015a, b), Sayadi and Sayyed (2011) also reported that cadmium is mainly from anthropogenic sources and are affected mostly by human interference.

 

 

Table 4 Potential ecological risk (ER) of heavy metals in cassava mill effluents contaminated soil

Note: Er < 40 (Low risk); Er 40 ≤ Er < 80 (Moderate risk); 80 ≤ Er < 160 (Considerable); 160 ≤ Er < 320 (High); Er ≥ 320 (Very high) BMM-Background median mean; BGM-Background geometric mean

 

Figure 1 present the makeup of the potential ecological risk index of the various metals under study. On the overall, cadmium > lead=nickel > cobalt > copper > chromium > zinc = manganese in wet season under BMM consideration and cadmium > lead = nickel = cobalt = copper > chromium > zinc = manganese in wet season under BGM scenario. In dry season, the ecological risk of the metals were in the order; cadmium > lead = nickel = copper > cobalt > chromium > zinc = manganese under BMM consideration and cadmium > lead > copper = cobalt > nickel > chromium > zinc = manganese under BGM consideration. The trend in this study is comparable to the work of Al-Anbari et al. (2015), who reported potential ecological risk of heavy metals in the order; cadmium > lead > nickel = cobalt > chromium = zinc is urban soil affected by anthropogenic activities.

 

 

Figure 1 Makeup of the potential ecological risk index

 

Furthermore, the ecological risk index is presented in Figure 2. In both seasons and background scenarios, the ecological risk was generally low. The low ecological risk index shown in this study is comparable to trend previously reported by Bhutiani et al. (2017). Typically, the ecological risk showed variation in toxicity of the different heavy metals (Zhu et al., 2012; Fu et al., 2014; Todorova et al., 2016).

 

 

Figure 2 Ecological risk index (R’) of heavy metals in cassava mill effluents contaminated soil 

Note: R’ <150 (Low risk); 150 ≤ R’ < 300 (Moderate risk); 300 ≤ R’ < 600 (Considerable); R’ ≥ 600 (Very high)

 

Table 5 presents the modified (Monomial) potential ecological risk of heavy metals from cassava mill effluents contaminated soil from a small-scale cassava processing mill in the Niger Delta region of Nigeria. The values for each of the heavy metals across the various sampling locations in both seasons (wet and dry) indicate low risk (MPER ≤ 50 ) apart from cadmium in LE which showed moderate risk (50 < MPER ≤ 100) under both background considerations in wet season. This is an indication of effect of season on soil contamination by cassava mill effluents. This trend suggests low ecological risk of the cassava mill effluents on soil quality.

 

 

Table 5 Modified (Monomial) potential ecological risk of heavy metals from cassava mille effluent contaminated soil

Note: MPER ≤ 50 (Low risk); 50 < MPER ≤ 100 (Moderate risk); 100 < MPER ≤ 150 (Considerable risk); 150 < MPER ≤ 200 (High risk); MPER > 200 (Very high/Extreme risk)

 

3 Conclusions

This study assessed the ecological risk assessment of heavy metals in cassava mill effluent contaminated soil in rural community in the Niger Delta region of Nigeria. The results of the ecological risk index of heavy metals (viz: Cr, Zn, Cu, Co, Ni, Mn, Pb and Cd) revealed that cassava mill effluents discharged into the environment by smallholder cassava processors in the Niger Delta had low ecological risk.

 

Acknowledgements

This paper is based on part of PhD project work of S.C. Izah supervised by Dr S.E. Bassey and Prof. E.I. Ohimain at the Niger Delta University, Wilberforce Island, Nigeria. The abstract was presented as E-Poster at the “12th International Conference on Environmental Toxicology and Ecological Risk Assessment” held in Atlanta, Georgia, USA between October 19-20, 2017.

 

References

Acosta J.A., Gabarron M., Faz A., Martínez-Martínez S., Zornoza R., and Arocena J.M., 2015, Influence of population density on the concentration and speciation of metals in the soil and street dust from urban areas, Chemosphere, 134: 28-337

https://doi.org/10.1016/j.chemosphere.2015.04.038

PMid:25966939

 

Al-Anbari R., Al Obaidy A.H.M.J., and Ali F.H.A., 2015, Pollution Loads and Ecological Risk Assessment of Heavy Metals in the Urban Soil Affected by Various anthropogenic Activities, International Journal of Advanced Research, 3(2): 104-110

 

Bhutiani R., Kulkarni D.B., Khanna D.R., and Gautam A., 2017, Geochemical distribution and environmental risk assessment of heavy metals in groundwater of an industrial area and its surroundings, Haridwar, India, Energy, Ecology and Environment, 2(2): 155-167

https://doi.org/10.1007/s40974-016-0019-6

 

Chen T.B., Wong J.W.C., Zhou H.Y., and Wong M.H., 1997, Assessment of trace metal distribution and contamination in surface soils of Hong Kong, Environmental Pollution, 96: 61-68

https://doi.org/10.1016/S0269-7491(97)00003-1

 

Chinyere C.G., Iroha A.E., and Amadike U.E., 2013, Effect of altering palm oil and cassava mill effluents pH before dumping on dumpsite soils physicochemical parameters and selected enzyme activities, Journal of Biodiversity and Environmental Sciences, 3(4): 46-58

 

Ehiagbonare J.E., Enabulele S.A., Babatunde B.B., and Adjarhore R., 2009, Effect of cassava effluents on Okada denizens, Scientific Research and Essay, 4(4): 310-313

 

Elias M.S., Hamzah M.S., Ab Rahman S., Salim N. A. A., Siong W.B. and Sanuri E. 2014, Ecological risk assessment of elemental pollution in sediment from Tunku AbdulRahman National Park, Sabah, American Institute of Physics Conference Proceedings, 1584, 196-206

 

El-Metwally M.E.A., Madkour A.G., Fouad R.R., Mohamedein L.I., Nour Eldine H.A., Dar M.A., and El-Moselhy Kh. M., 2017, Assessment the leachable heavy metals and ecological risk in the surface sediments inside the Red Sea ports of Egypt, International Journal of Marine Science, 7(23): 214-228

https://doi.org/10.5376/ijms.2017.07.0023

 

Eneje R., and Ifenkwe I., 2012, Effect of agricultural and industrial wastes on the physicochemical properties of a sandy clay loam soil, International Journal of Applied Agricultural Research, 7(3): 187-196

 

Eze V.C., and Onyilide D.M., 2015, Microbiological and physiochemical characteristics of soil receiving cassava effluents in Elele, Rivers state, Nigeria, Journal of Applied and Environmental Microbiology, 3(1): 20-24

 

Ezeigbo O.R., Ike-Amadi C.A., Okeke U.P., and Ekaoko M.U., 2014, The effect of cassava mill effluent on soil microorganisms in Aba, Nigeria, International Journal of Current Research in Bioscience and Plant Biology, 1(4): 21-26

 

Fiori C.S., Rodigues A.P.C., Santelli R.E., Cordeiro R.C., Carvalheira R.G., Araujo P. C.,  Castihos Z.C., and Bidone E.D., 2013, Ecological risk index for aquatic pollution control: a case study of coastal water bodies from the Rio de Janeiro state, southeaster Brazil, Geochimical Brasiliensis, 27(1): 24-3

https://doi.org/10.5327/Z0102-9800201300010003

 

Fu J., Zhao C., Luo Y., Liu C., Kyzas G.Z., Luo Y., Zhao D., An S., and Zhu H., 2014, Heavy metals in surface sediments of the Jialu River, China: their relations to environmental factors, Journal of Hazardous Material, 270: 102-109

https://doi.org/10.1016/j.jhazmat.2014.01.044

PMid:24561322

 

Gasiorek M., Kowalska J., Mazurek R., and Pajak M., 2017, Comprehensive assessment of heavy metal pollution in topsoil of historical urban park on an example of the Planty Park in Krakow (Poland), Chemosphere, 179: 148-158

https://doi.org/10.1016/j.chemosphere.2017.03.106

PMid:28365500

 

Ghaleno OR., Sayadi M.H., and Rezaei M.R., 2015, Potential ecological risk assessment of heavy metals in sediments of water reservoir case study: Chah Nimeh of Sistan, Proceedings of the International Academy of Ecology and Environmental Sciences, 5(4), 89-96

 

Gu Y.G., Gao Y.P., and Lin Q., 2016, Contamination, bioaccessibility and human health risk of heavy metals in exposed-lawn soils from 28 urban parks in southern China's largest city, Guangzhou, Appl. Geochem, 67: 52-58

https://doi.org/10.1016/j.apgeochem.2016.02.004

 

Guan Y., Shao C., and Ju M., 2014, Heavy metal contamination assessment and partition for industrial and mining gathering areas, International Journal of Environmental Research and Public Health, 11: 7286-7303

https://doi.org/10.3390/ijerph110707286

PMid:25032743 PMCid:PMC4113876

 

Hakanson L., 1980, An ecological risk index for aquatic pollution control, A sedimentological approach, Water Research, 14: 975-1001

https://doi.org/10.1016/0043-1354(80)90143-8

 

Hassaan M.A., Nemr A.E., and Madkour F.F., 2016, Environmental Assessment of Heavy Metal Pollution and Human Health Risk, American Journal of Water Science and Engineering, 2(3): 14-19

 

Ibe I.J., Ogbulie J.N., Odum D.C., Onyirioha C., Peter-Ogu P., and Okechi R.N., 2014, Effects of cassava mill effluent on some groups of soil bacteria and soil enzymes, International Journal of Current Microbiology and Applied Sciences, 3(10): 284-289

 

Idris M.A., Kolo B.G., Garba S.T., and Waziri I., 2013, Pharmaceutical Industrial Effluent: Heavy Metal Contamination of Surface water in Minna, Niger State, Nigeria, Bulletin of Environmental Pharmacology and Life Science, 2 (3), 40-44

 

Igbinosa E.O., 2015, Effect of cassava mill effluent on biological activity of soil microbial community, Environmental Monitoring Assessment, 187: 418

https://doi.org/10.1007/s10661-015-4651-y

PMid:26055654

 

Igbinosa E.O., and Igiehon O.N., 2015, The impact of cassava effluent on the microbial and physicochemical characteristics on soil dynamics and structure, Jordan Journal of Biological Sciences, 8(2): 107-112

https://doi.org/10.12816/0027556

 

Izah, S.C., Bassey, S.E., and Ohimain, E.I., 2017a, Changes in the treatment of some physico-chemical properties of cassava mill effluents using Saccharomyces cerevisiae, Toxic, 5(4), 28

https://doi.org/10.3390/toxics5040028

PMid:29051460

 

Izah, S.C., Bassey, S.E., and Ohimain, E.I., 2017b, Removal of Heavy Metals in Cassava Mill Effluents with Saccharomyces cerevisiae isolated from Palm Wine, MOJ Toxicology, 3(4): 00057

 

Izah S.C., Bassey S.E., and Ohimain E.I., 2017c, Assessment of heavy metal in cassava mill effluent contaminated soil in a rural community in the Niger Delta region of Nigeria, EC Pharmacology and Toxicology, 4(5): 186-201

 

Izah S.C., Bassey S.E., and Ohimain E.I., 2017d, Assessment of some selected Heavy metals in Saccharomyces cerevisiae biomass produced from Cassava mill effluents, EC Microbiology 12(5): 213-223

 

Izah S.C., Bassey S.E., and Ohimain E.I., 2017e, Assessment of pollution load indices of heavy metals in cassava mill effluents contaminated soil: a case study of small-scale cassava processing mills in a rural community of the Niger Delta region of Nigeria, Bioscience Methods, 8(1): 1-17

https://doi,org/10.5376/bm.2017.08.0001.

 

Izah S.C., Bassey S.E., and Ohimain E.I., 2017f., Amino acid and proximate composition of Saccharomyces cerevisiae biomass cultivated in Cassava mill effluents, Molecular Microbiology Research, 7(3): 20-29

https://doi.org/10.5376/mmr.2017.07.0003

 

Izah S.C., Bassey S.E., and Ohimain E.I., 2017g, Geo-accumulation index, enrichment factor and quantification of contamination of heavy metals in soil receiving cassava mill effluents in a rural community in the Niger Delta region of Nigeria, Molecular Soil Biology, 8(2): 7-20

https://doi.org/10.5376/msb.2017.08.0002

 

Izah S.C., Inyang I.R., Angaye T.C.N., and Okowa I.P., 2017h, A review of heavy metal concentration and potential health implications in beverages consumed in Nigeria, Toxics, 5 (1), 1-15

https://doi.org/10.3390/toxics5010001

PMid:29051433 PMCid:PMC5606672

 

Izah S.C., and Aigberua A.O., 2017, Assessment of Microbial Quality of Cassava Mill Effluents Contaminated Soil in a Rural Community in the Niger Delta, Nigeria, EC Microbiology, 13(4): 132-140

 

Izah S.C., 2016, Bioethanol production from cassava mill effluents supplemented with oil palm chaff, empty fruit bunch and cassava peels using Saccharomyces cerevisiae, M.Sc. thesis submitted to School of Post Graduate Studies, Niger Delta University, Wilberforce Island, Nigeria, 113p

 

Izah S.C., and Angaye T.C.N., 2016, Heavy metal concentration in fishes from surface water in Nigeria: Potential sources of pollutants and mitigation measures, Sky Journal of Biochemistry Research, 5(4): 31-47

 

Izah S.C., Chakrabarty N., and Srivastav A.L., 2016, A Review on Heavy Metal Concentration in Potable Water Sources in Nigeria: Human Health Effects and Mitigating Measures, Exposure and Health, 8: 285-304

https://doi.org/10.1007/s12403-016-0195-9

 

Izah S.C., and Ohimain E.I., 2015, Bioethanol production from cassava mill effluents supplemented with solid agricultural residues using bakers’ yeast [Saccharomyces cerevisiae], Journal of Environmental Treatment Techniques, 3(1): 47-54

 

Izonfuo W-A.L., Bariweni P.A., and George D.M.C., 2013, Soil contamination from cassava wastewater discharges in a rural community in the Niger Delta, Nigeria, Journal of Applied Science and Environmental Management, 17(1): 105-110

 

Jiang X., Lu W.X., Zhao H.Q., Yang Q.C., and Yang Z.P., 2014, Potential ecological risk assessment and prediction of soil heavy-metal pollution around coal gangue dump, Natural Hazards and Earth System Science, 14: 1599-1610

https://doi.org/10.5194/nhess-14-1599-2014

 

Karydas C.G., Tzoraki O., and Panagos P., 2015, A New Spatiotemporal Risk Index for Heavy Metals: Application in Cyprus, Water, 7: 4323-4342

https://doi.org/10.3390/w7084323

 

Kowalska J., Mazurek R., Ga˛siorek M., Setlak M., Zaleski T., Waroszewski J., 2016, Soil pollution indices conditioned by medieval metallurgical activity-a case study from Krakow (Poland), Environmental Pollution, 218: 1023-1036

https://doi.org/10.1016/j.envpol.2016.08.053

PMid:27574802

 

Mazurek R., Kowalska J., Gasiorek M., Zadrozny P., Jozefowska A., Zaleski T., Kepka W., Tymczuk M., and Orłowska K., 2017, Assessment of heavy metals contamination in surface layers of Roztocze National Park forest soils (SE Poland) by indices of pollution, Chemosphere, 168: 839-850

https://doi.org/10.1016/j.chemosphere.2016.10.126

PMid:27829506

 

Mohseni-Bandpei A., Ashrafi SD., Kamani H., and Paseban A., 2016, Contamination and Ecological Risk Assessment of Heavy Metals in Surface Soils of Esfarayen City, Iran, Health Scope, e39703

 

Monakhov S., Esina O., Monakhova G., and Tatarnikov V., 2015, Environmental quality assessment: geoenvironmental indices, In: Environmental indicators, Armon R.H., and Hanninen O. (eds). Springer, Dordrecht

https://doi.org/10.1007/978-94-017-9499-2_27

 

Muhammad I., Ashiru S., Ibrahim I.D., Salawu K., Muhammad D.T., and Muhammad N.A., 2014, Determination of some heavy metals in wastewater and sediment of artisanal gold local mining site of Abare Area in Nigeria, Journal of Environmental Treatment Techniques, 1(3): 174-182

 

Nwakaudu M.S., Kamen F.L., Afube G., Nwakaudu A.A., and Ike I.S., 2012, Impact of Cassava Processing Effluent on Agricultural Soil: A Case Study of Maize Growth, Journal of Emerging Trends in Engineering and Applied Sciences, 3(5): 881-885

 

Nwaugo V.O., Etok C.A., Chima G.N., and Ogbonna C.E., 2008, Impact of Cassava Mill Effluent (CME) on Soil Physicochemical and Microbial Community Structure and Functions, Nigerian Journal of Microbiology, 22(1): 1681-1688

 

Nwaugo V.O., Onyeagba R.A., Umeham S.N., and Azu N., 2007, Effect of physicochemical properties and attachment surfaces on biofilms in cassava mill effluent polluted Oloshi River, Nigeria, Estudos de Biologia, 29(66): 53-61

 

Ohimain EI., Silas-Olu DI., and Zipamoh J.T., 2013, Biowastes generation by small scale cassava processing centres in Wilberforce Island, Bayelsa State, Nigeria, Greener Journal of Environmental Management and Public Safety, 2 (1): 51-59

https://doi.org/10.15580/GJEMPS.2013.1.112712294

 

Okechi R.N., Ihejirika C.E., Chiegboka N.A., Chukwura E.I., and Ibe I.J., 2012, Evaluation of the effects of cassava mill effluents on the microbial populations and physicochemical parameters at different soil depths, International Journal of Bioscience, 2(12), 139-145

 

Omomowo I.O., Omomowo O.I., Adeeyo A.O., Adebayo E.A., and Oladipo E.K., 2015, Bacteriological Screening and Pathogenic Potential of Soil Receiving Cassava Mill Effluents, International Journal of Basic and Applied Science, 03 (4): 26-36

 

Omotioma M., Mbah G.O., Akpan I.J., and Ibezim O.B., 2013, Impact assessment of cassava effluents on barika stream in Ibadan, Nigeria. International Journal of Environmental Science, Management and Engineering Research, 2 (2): 50-56

 

Orji E.A., and Egboka B.C.E., 2015, The Hydrogeology of Delta State, Nigeria, The Pacific Journal of Science and Technology, 16(2): 257-269

 

Osakwe S.A., 2012, Effect of Cassava Processing Mill Effluent on Physical and Chemical Properties of Soils in Abraka and Environs, Delta State, Nigeria, Chemistry and Materials Research, 2(7): 27-40

 

Parzych A., Sobisz Z., and Trojanowski J., 2012, Prognosis content of heavy metals in soil and herbaceous plants in selected pine forests in the Słowinski National Park, Arch. Environ. Prot. 38, 35-47

https://doi.org/10.2478/v10265-012-0038-0

 

Qingjie G., Jun D., Yunchuan X., Qingfei W., and Liqiang Y., 2008, Calculating Pollution Indices by Heavy Metals in Ecological Geochemistry Assessment and a Case Study in Parks of Beijing, Journal of China University of Geosciences, 19(3): 230-241

https://doi.org/10.1016/S1002-0705(08)60042-4

 

Qiu H., 2010, Studies on the Potential Ecological Risk and Homology Correlation of Heavy Metal in the Surface Soil, Journal of Agricultural Science, 2(2): 194-201

https://doi.org/10.5539/jas.v2n2p194

 

Sayadi M.H., and Sayyed M.R.G., 2011, Comparative assessment of baseline concentration of the heavy metals in the soils of Chitgar Industrial Area Tehran (Iran) with the comprisable reference data, Environmental Earth Sciences, 63: 1179-1188

https://doi.org/10.1007/s12665-010-0792-z

 

Sayadi M.H., Shabani M., and Ahmadpoor N., 2015a, Pollution index and ecological risk of heavy metals in the surface soils of Amir-Abad Area in Birjand City, Iran, Health Scope, 4(1): e21137

https://doi.org/10.17795/jhealthscope-21137

 

Sayadi M.H., Rezaei M.R., Rezaei A., 2015b, Sediment Toxicity and ecological risk of trace metals from streams surrounding a municipal solid waste landfill. Bulletin of Environmental Contamination and Toxicology, 94(5): 559-563

https://doi.org/10.1007/s00128-015-1518-4

PMid:25761439

 

Singovszka E., Balintova M., and Holub, M., 2014, Assessment of Heavy Metals Concentration in Sediments by Potential Ecological Risk Index, Journal of the Polish Mineral Engineering Society, No volume: 137-140

 

Sofianska E., and Michailidis K., 2016, Assessment of Heavy Metals Contamination and Potential Ecological Risk in Soils Affected by a Former Mn Mining Activity, Drama District, Northern Greece, Soil and Sediment Contamination: An International Journal, 25 (3): 296-312

https://doi.org/10.1080/15320383.2016.1133560

 

Soliman N.F., Nasr S.M., and Okbah M.A., 2015, Potential ecological risk of heavy metals in sediments from the Mediterranean coast, Egypt, Journal of Environmental Health Science and Engineering, 13: 70

https://doi.org/10.1186/s40201-015-0223-x

PMid:26457189 PMCid:PMC4600254

 

Swarnalatha K., Letha J., and Ayoob S., 2013, Ecological risk assessment of a tropical lake system, Journal of Urban and Environmental Engineering, 7(2): 323-329

https://doi.org/10.4090/juee.2013.v7n2.323329

 

Tang W., Shan B., Zhang H., Zhang W., Zhao Y., Ding Y., Rong N., and Zhu X., 2014, Heavy Metal Contamination in the Surface Sediments of Representative Limnetic Ecosystems in Eastern China, Scientific Reports, 4: 7152

https://doi.org/10.1038/srep07152

PMid:25412580 PMCid:PMC4239569

 

Thambavani S.D., and Uma Mageswari UTSR., 2013, Metal pollution assessment in ground water. Bulletin of Environmental Pharmacology Life Science, 2(12): 122-129

 

Todorova Y., Lincheva S., Yotinov I., and Topalova Y., 2016, Contamination and Ecological Risk Assessment of Long-Term Polluted Sediments with Heavy Metals in Small Hydropower Cascade, Water Resource Management, 30: 4171-4184

https://doi.org/10.1007/s11269-016-1413-8

 

Vowotor M.K., Hood C.O., Sackey S.S., Owusu A., Tatchie E., Nyarko S., Osei D.M., Mireku K.K., Letsa C.B., and Atieomo S.M., 2014, An Assessment of Heavy Metal Pollution in Sediments of a Tropical Lagoon: A Case Study of the Benya Lagoon, Komenda Edina Eguafo Abrem Municipality (KEEA)-Ghana, Journal of Health and Pollution, 4(6): 26-39

https://doi.org/10.5696/2156-9614-4-6.26

 

Wei B., and Yang L., 2010, A review of heavy metal contaminations in urban soils, urban road dusts and agricultural soils from China, Microchem, J. 94: 99-107

https://doi.org/10.1016/j.microc.2009.09.014

 

Xu Z.Q., Ni S. J., and Tuo X.G., 2008, Calculation of heavy metals toxicity coefficient in the evaluation of potential ecological risk index, Environmental Science and Technology, 31: 112-115

 

Yang Z.P., Lu W.X., Long Y.O., Bao X.H., and Yang Q.C., 2011, Assessment of heavy metals contamination in urban topsoil from Changchun City, China, Journal of Geochemical Exploration, 108: 27-38

https://doi.org/10.1016/j.gexplo.2010.09.006

 

Yisa N. J., John O., Christian J., and Onoyima C., 2012, Assessment of toxic levels of some heavy metals in road deposited sediments in Suleja, American Journal of Chemistry, 2(2): 34-37

https://doi.org/10.5923/j.chemistry.20120202.08

 

Zhang H., and Shan B. Q., 2008, Historical records of heavy metal accumulation in sediments and the relationship with agricultural intensification in the Yangtze- Huaihe region, China, Science of the Total Environment, 399: 113-120

https://doi.org/10.1016/j.scitotenv.2008.04.045

https://doi.org/10.1016/j.scitotenv.2008.03.036

PMid:18479736

 

Zhu H., Yuan X., Zeng G., Jiang M., Liang J., Zhang C., Yin J., Huang H., Liu Z., and Jiang H., 2012, Ecological risk assessment of heavy metals in sediments of Xiawan Port based on modified potential ecological risk index, Transactions of Nonferrous Metals Society of China, 22: 1470-1477

https://doi.org/10.1016/S1003-6326(11)61343-5

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