**1. Introduction**

190 Recent Advances in Plasticizers

Sivakumar, M., Subadevi, R., Rajendran, S., Wu, N.L. & Lee, J.Y. (2006). Electrochemical

Stephan, A.M., Kumar, T.P., Renganathan, N.G., Pitchumani, S., Thirunakaran, R. &

Stephan, A. M., Renganathan, N.G., Kumar, T.P., Thirunakaran, R., Pitchumani, S.,

Stephan, A.M., Saito, Y., Muniyandi, N., Renganathan, N.G., Kalyanasundaram, S. &

Stephan, A.M. (2006). Review on gel polymer electrolytes for lithium batteries. *European Polymer Journal*, Vol. 42, No. 1, (January 2006), pp. 21–42, ISSN 0014–3057. Suthanthiraraj, S.A., Sheeba, D.J. & Paul, B.J. (2009). Impact of ethylene carbonate on ion

*Research Bulletin*, Vol. 44, No. 7, (July 2009), pp. 1534–1539, ISSN 0025–5408. Tobishima, S.I. & Yamaji, A. (1984). Ethylene carbonate–propylene carbonate mixed

Tobishima, S.I., Hayashi, K., Nemoto, Y., Yamaki, J.–I. (1997). Ethylene carbonate/propylene

Xu, J., Lu, B., & Fan, S. (2004). Industrial Growth of Lithium Tetraborate (Li2B407)

Xu, J.J. & Ye, H. (2005). Polymer gel electrolytes based on oligomeric polyether/cross–linked

*Communications*, Vol. 7, No. 8, (August 2005), pp. 829–835, ISSN 1388–2481. Yang, Y., Zhou, C.H., Xu, S., Hu, H., Chen, B. L., Zhang, J., Wu, S.J., Liu, W., Zhao, X. Z., et

*Ionics*, Vol. 130, No. 1–2, (May 2000), pp. 123–132, ISSN 0167–2738.

ISSN 0254–0584.

(July 2000), pp. 80–87, ISSN 0378–7753.

3–4, (June 2002), pp. 467–473, ISSN 0167–2738.

11, (May 1997), pp. 1709–1716, ISSN 0013–4686.

1–2, (September 2011), pp. 80–85, ISSN 0376–7388.

pp. 267–271, ISSN 0013–4686.

October 2004.

studies on [(1−*x*)PVA–*x*PMMA] solid polymer blend electrolytes complexed with LiBF4 , *Materials Chemistry and Physics*, Vol. 97, , No. 2–3, (June 2006), pp. 330–336,

Muniyandi, N. (2000a). Ionic conductivity and FT–IR studies on plasticized PVC/PMMA blend polymer electrolytes. *Journal of Power Sources*, Vol. 89, No. 1,

Shrisudersan, J. & Muniyandi, N. (2000b). Ionic conductivity studies on plasticized PVC/PMMA blend polymer electrolyte containing LiBF4 and LiCF3SO3. *Solid State* 

Elizabeth, R.N. (2002). Preparation and characterization of PVC/PMMA blend polymer electrolytes complexed with LiN(CF3SO2)2. *Solid State Ionics*, Vol. 148, No.

transport characteristics of PVdF–AgCF3SO3 polymer electrolyte system. *Materials* 

electrolytes for lithium batteries. *Electrochimica Acta*, Vol. 29, No. 2, (February 1984),

carbonate/2–methyl–tetrahydrofuran ternary mixed solvent electrolyte for rechargeable lithium/amorphous V2O5–P2O5 cells. *Electrochimica Acta*, Vol. 42, No.

Piezocrystal and Its SAW Applications. *Proceedings of 7th international conference on Solid–State and Integrated Circuits Technology*, ISBN 0–7803–8511–X, China:Beijing,

PMMA blends prepared via in situ polymerization. *Electrochemistry* 

al. (2008). Improved stability of quasi–solid–state dye sensitized solar cell based on poly(ethylene oxide)–poly(vinylidene fluoride) polymer–blend electrolytes. *Journal of Power Sources*, Vol. 185, No. 2, (December 2008), pp. 1492–1498, ISSN 0378–7753. Zhang, P., Yang, L.C., Li, L.L., Ding, M.L., Wua, Y.P. & Holze, R. (2011). Enhanced

electrochemical and mechanical properties of P(VDF–HFP)–based composite polymer electrolytes with SiO2 nanowires. *Journal of Membrane Science*, Vol. 379, No. A variety of human activities e.g. agricultural activities, urban and industrial development, mining and recreation, significantly alter the quality of natural waters, and changes the water use potential (Spinks et al., 2006; Madungwe and Sakuringwa, 2007). The key to sustainable water resources is, therefore to ensure that the quality of water resources are suitable for their intended uses, while at the same time allowing them to be used and developed to a certain extent. Water quality management, therefore involves the maintenance of the fitness for use of water resources on a sustained basis, by achieving a balance between socio-economic development and environmental protection. Approximately 40 000 small-scale farmers, 15 000 medium-to-large-scale farmers, 120 000 permanent workers, and an unknown number of seasonal workers are involved in irrigation farming, which consumes approximately 51 to 61 % of South Africa's water on some 1,3 million hectares (Backeberg, 1996; Blignaut and Heerden, 2008). Irrigation farming contributes 25 to 30 % of South Africa's agricultural output. Agriculture is crucially important to the basic food security of the poor, who constitute 40 % of the population of 42 million, and who are overwhelmingly concentrated in rural areas and (peri-) urban townships (Blignaut and Heerden, 2008).

Like many countries in the world, water scarcity is becoming a major problem in South Africa (Marcucci & Tognotti, 2002; Oweis & Hachum, 2009; Komnenic *et al*., 2009) as dams serving communities with drinking water and water for daily household use, have been less than 30% full in recent years (Qiao *et al*., 2009; Malley *et al*., 2009). River water, in combination with groundwater, effluents from wastewater treatment plants, is considered a suitable alternative as a utilisable and potable water source (Blignaut and Heerden, 2008). To complement scare water resources, there has been increase in the number of wastewater facilities in many countries. This is to forestall the outbreak of environmental pollution and spread of diseases, remove conventional pollutants (such as ammonia and phosphate), and to maintain and restore the biologic integrity of surface waters (Wang *et al*., 2005; Sun *et al*., 2008). Domestic and industrial wastewaters are significant sources of endocrine disrupting chemicals

Health Risk Assessment of Plasticizer in Wastewater Effluents and Receiving Freshwater Systems 193

defined it as a process in which information is analyzed to determine if an environmental

In addition to definition, NRC proposed a framework for human health risk assessment,

This step can be defined as the qualitative determination of whether or not a particular hazardous agent is associated with health effects of sufficient importance to warrant further scientific investigations. Different kinds of tools (QSAR, short-term toxicity test) are used in order to estimate the chemical damage of a single substance. When establishing the hazard from industrial sources, the chemicals are also identified according to measurements of

This component is focused on examining quantitative relationships between the magnitude of the exposure (or dose) and the probability of occurrence of adverse effects in the population. Usually, dose-response assessment is based on extrapolations from data about laboratory animals, which have been given high-doses of toxicant and monitored

Exposure assessment may be defined as the quantitative determination of the extent of exposure of the population to the hazardous agent in question. Since they provide a real knowledge of the state of pollution of an area, data obtained in the environmental monitoring are commonly used as a starting point. Factors that need to be considered include frequency and duration of exposure, rates of uptake or contact, and rate of absorption (NRC, 1993). Other factors in assessing exposure include release patterns, cumulative versus non-cumulative exposure, persistence, failure of exposure controls,

This fourth component can be defined as the description of the nature and magnitude of the risk, expressed in terms which are comprehensible to decision makers and the public. Information acquired in the previous 3 steps is integrated in order to communicate the overall meaning of, and confidence in, the hazard, exposure, and risk conclusions. Risk is expressed as a probability of suffering a particular kind of harm from a hazard to a specified group of population (Bennion *et al*., 2005). Moreover, qualitative and quantitative

hazard might cause harm to exposed persons and ecosystems (NRC, 1983).

which involved 4 basic steps (NRC, 1993). The four steps of the process are:

1. Hazard identification 2. Dose-response assessment 3. Exposure assessment and 4. Risk characterization.

**1.1.1 Hazard identification** 

amount and typology of emissions.

**1.1.2 Dose-response assessment** 

**1.1.3 Exposure assessment** 

quality of data and quality of models.

uncertainty related to risk must be also supplied.

**1.1.4 Risk characterization** 

accordingly.

(EDCs) to the receiving surface, coastal waters and regional environments (Ahel *et al*., 1994; Ahel *et al*., 1996; Ying *et al*., 2002; Vethaak *et al*., 2005; Voutsa *et al*., 2006; Zuccato *et al*. 2006).

South African rivers are steadily becoming more contaminated and in some cases even toxic, due to urbanization, industrialization and malfunctioning of wastewater treatment plants in the cities (Fatoki et al., 2004; Jackson et al., 2007; Jackson et al., 2009). Water quality in South Africa has been a major debate considering the water consumption trend in the country both for agricultural development, recreational purposes and domestication usage. Of the major water pollutants that have been relegated to the background in South Africa is Phthalate esters (PE). There was no local interim guidelines for PE in freshwater systems in South Africa, thus pollution of freshwater systems through industrial activities could not be punished. However, water quality is of paramount importance in this country.

Phthalate ester is synthetic compound commonly used as a plasticizer to impart flexibility, workability, and durability to polymers such as polyvinyl chloride. Also, this compound is used in a wide variety of products such as paints, adhesives, inks and cosmetics (Ling et al., 2007; Huang et al., 2007). As a result, PE has become ubiquitously distributed in the environment and easily finds their ways into the river systems through both dry and wet deposition (Yuan et al., 2002; Yuan et al., 2008). PE is considered to be a potential carcinogen, teratogen, and mutagen. Their toxicity to human beings and aquatic organisms is of deep concern (Mylchreest et al., 1999; Awal et al., 2004; Fatoki et al., 2010).

Furthermore, PE acts as endocrine disruptors, which could alter reproductive functions and exert distinct effects on male reproductive organs due to anti-androgenic effects (Latini et al., 2006; Lambrot et al., 2009; Vo et al., 2009). The aim of this study was to assess the potential human impacts health associated with PE found in the final effluent from wastewater treatment plants and river water receiving effluent wastes.

#### **1.1 The risk assessment framework**

In recent decades, the interest about environmental issues has increased very quickly. Not only to the natural scientists, but other active members of the society (politicians, industrialists and the general public), have paid much attention in all aspects related to the environment, in general, and environment protection, in particular. In this context, environmental pollution has been one of the fields where more efforts have been aimed to control. Because of the lack of environmental consciousness and technical capacity, many industries released toxic substances into the air, water and soil, for a number of years. As a first consequence, levels of pollution in areas surrounding industrial sites became much higher than background (unpolluted) zones. Recently, implementation of legislative measures carried out by public administrations has obliged to companies to improve their production processes in order to reduce the pollutant emissions.

The concern resulting from the potential exposure to contaminants initiated the development of methodologies that evaluate the consequences that those contaminants can have on environment and human health. Among these methods, risk assessment has been one of the most widely used. Risk assessment is a formalized process for estimating the magnitude, likelihood, and uncertainty of environmentally induced health effects (Sexton *et al*., 1995). In 1983, the US National Research Council (NRC), in the so-called "Red Book", defined a series of principles to be considered for human health risk assessment, and defined it as a process in which information is analyzed to determine if an environmental hazard might cause harm to exposed persons and ecosystems (NRC, 1983).

In addition to definition, NRC proposed a framework for human health risk assessment, which involved 4 basic steps (NRC, 1993). The four steps of the process are:

1. Hazard identification

192 Recent Advances in Plasticizers

(EDCs) to the receiving surface, coastal waters and regional environments (Ahel *et al*., 1994; Ahel *et al*., 1996; Ying *et al*., 2002; Vethaak *et al*., 2005; Voutsa *et al*., 2006; Zuccato *et al*. 2006).

South African rivers are steadily becoming more contaminated and in some cases even toxic, due to urbanization, industrialization and malfunctioning of wastewater treatment plants in the cities (Fatoki et al., 2004; Jackson et al., 2007; Jackson et al., 2009). Water quality in South Africa has been a major debate considering the water consumption trend in the country both for agricultural development, recreational purposes and domestication usage. Of the major water pollutants that have been relegated to the background in South Africa is Phthalate esters (PE). There was no local interim guidelines for PE in freshwater systems in South Africa, thus pollution of freshwater systems through industrial activities could not be

Phthalate ester is synthetic compound commonly used as a plasticizer to impart flexibility, workability, and durability to polymers such as polyvinyl chloride. Also, this compound is used in a wide variety of products such as paints, adhesives, inks and cosmetics (Ling et al., 2007; Huang et al., 2007). As a result, PE has become ubiquitously distributed in the environment and easily finds their ways into the river systems through both dry and wet deposition (Yuan et al., 2002; Yuan et al., 2008). PE is considered to be a potential carcinogen, teratogen, and mutagen. Their toxicity to human beings and aquatic organisms

Furthermore, PE acts as endocrine disruptors, which could alter reproductive functions and exert distinct effects on male reproductive organs due to anti-androgenic effects (Latini et al., 2006; Lambrot et al., 2009; Vo et al., 2009). The aim of this study was to assess the potential human impacts health associated with PE found in the final effluent from

In recent decades, the interest about environmental issues has increased very quickly. Not only to the natural scientists, but other active members of the society (politicians, industrialists and the general public), have paid much attention in all aspects related to the environment, in general, and environment protection, in particular. In this context, environmental pollution has been one of the fields where more efforts have been aimed to control. Because of the lack of environmental consciousness and technical capacity, many industries released toxic substances into the air, water and soil, for a number of years. As a first consequence, levels of pollution in areas surrounding industrial sites became much higher than background (unpolluted) zones. Recently, implementation of legislative measures carried out by public administrations has obliged to companies to improve their

The concern resulting from the potential exposure to contaminants initiated the development of methodologies that evaluate the consequences that those contaminants can have on environment and human health. Among these methods, risk assessment has been one of the most widely used. Risk assessment is a formalized process for estimating the magnitude, likelihood, and uncertainty of environmentally induced health effects (Sexton *et al*., 1995). In 1983, the US National Research Council (NRC), in the so-called "Red Book", defined a series of principles to be considered for human health risk assessment, and

punished. However, water quality is of paramount importance in this country.

is of deep concern (Mylchreest et al., 1999; Awal et al., 2004; Fatoki et al., 2010).

wastewater treatment plants and river water receiving effluent wastes.

production processes in order to reduce the pollutant emissions.

**1.1 The risk assessment framework** 

