Effect of storage temperature and sunlight exposure on the physicochemical properties of bottled water in Kurdistan region-Iraq

Physicochemical properties (pH, Electrical conductivity, Total dissolved salt, Cl , F , NO3 , SO4 , NH4 + and Chemical oxygen demand) of Sixteen brands bottled water in Kurdistan region-Iraq were analyzed using standard methods. The physicochemical properties of the bottled water measured in this work compared with manufacturer's labeling reported on the bottles and were compared with the guideline value of World Health Organization (WHO) and International Bottled Water Association (IBWA) standards. The change of physicochemical properties investigated when the bottled water exposed to sunlight or storage at different temperature for 30 days. IR-spectroscopy was carried out in order to deduce the nature of polymer material and its purity. Results indicated that the quality of bottled water samples was within the permissible limit, while it is changed with the time of sunlight exposed or temperature changes. The results indicate, the physicochemical properties of all bottled water samples are within the international guidelines of bottled water and not the same that reported on the bottle label. The results show each of sun light exposure and temperature of storing cause changes in all physicochemical properties of water in the plastic bottle. @JASEM Bottled water consumption has been steadily growing up the last three decades in a global level. The main reason for this rapid consumption was the lack of safe and accessible drinking water and the taste of chemicals, particularly chlorine, used to purify tap water (Samadi MT. et al. 2009). Bottled water quality are subjected to intensive investigation in many countries worldwide, in order to evaluate its suitability for human consumption. The quality of water may vary from one source to another based on several parameters such as water sources, type of water purification, and storage tanks (Mufeed I. 2006).The quality and physicochemical properties of bottled water have been study extensively in many countries, for examples in Saudi Arabia (Maqbool Ahmad. Et al. 2009), Greek (Stavroula V. et al. 2008), Brazil (C. P. Jordao. et al. 2007), Iran (Samadi MT. et al. 2009), United Arab Emirates (Zeinelabidin . 2009), South Korean (Bong YS. et al. 2008), Kuwait (Al-Mudhaf HF.et al 2009), Jordan (Mufeed I. 2006 ) , Bahrain (Musaiger A. et al. 1990), Canada (Page, B. D.et al. 1993 ) and USA (Allen, H.et al 1989 ). Polyethylene terephthalate (PET) is the material most commonly used to make the clear plastic bottles in which bottled water is sold. The contents of the PET bottle, and the temperature at which it is stored, both appear to influence the rate and magnitude of leaching of organic and inorganic compounds from pet bottle (Peter Schmida.et al 2008). Several studies have shown the presence of compounds in bottled water, in non negligible concentrations. Mutsuga M. et al (Mutsuga M.et al.2006) reported the acetaldehyde forming during the polymerization reaction and the hot step process in the bottle water manufacture. Farhoodi et al. (Farhoodi et al. 2008) studied the interaction of incubation time with storage temperature on the leaching of DEHP from PET bottles. Cristina Bach et al. (Cristina Bach et al.2009) tested water bottles after exposure to extreme conditions of high temperature and UV radiation to accelerate the possible migration of substances. In sunlight exposure tests, Wegelin et al. (Wegelin et al. 2001) have shown that PET degradation products such as terephthalate monomers and dimers are primarily formed at the surface of the bottles. Peter Schmid et al. (Peter Schmid et al. 2008) sought to determine whether solar water disinfection (SODIS) would promote leaching of phthalates into water in PET bottles. SODIS is a technique used in developing countries to disinfect water by incubating water in PET bottles in direct sunlight. After 17 hr of incubation in direct sunlight, maximum concentrations of di(2-ethylhexyl)adipate and DEHP were 0.046 and 0.71 μg/L, respectively.From the literature on leaching of PET it becomes evident that time is a dominant factor governing the release of organic substances (Nawrocki, J.et al. 2002). During the five years, there has been a considerable increase in the consumption of bottled water in Kurdistan region (north of Iraq), especially in the summer .According to the ministry of industry in 2010, 27 bottled water companies in Kurdistan region produced about 1.692 x 10 9 L of bottled water. Bottled water is also imported from Turkey country. The biggest bottled water production company in Kurdistan region is Life Company which produces 27 * 10 6 liter bottled water per year. The main source of bottled water sold in Kurdistan region is from springs, wells and surface water. Temperatures in Kurdistan region exceed 45°C at the summer time and the storing of bottled water in the car or out the

Bottled water consumption has been steadily growing up the last three decades in a global level.The main reason for this rapid consumption was the lack of safe and accessible drinking water and the taste of chemicals, particularly chlorine, used to purify tap water (Samadi MT. et al. 2009).Bottled water quality are subjected to intensive investigation in many countries worldwide, in order to evaluate its suitability for human consumption.The quality of water may vary from one source to another based on several parameters such as water sources, type of water purification, and storage tanks (Mufeed I. 2006).The quality and physicochemical properties of bottled water have been study extensively in many countries, for examples in Saudi Arabia (Maqbool Ahmad. Et al. 2009), Greek (Stavroula V. et al. 2008), Brazil (C.P. Jordao. et al. 2007), Iran (Samadi MT. et al. 2009), United Arab Emirates (Zeinelabidin .2009), South Korean (Bong YS. et al. 2008), Kuwait (Al-Mudhaf HF.et al 2009), Jordan (Mufeed I. 2006 ) , Bahrain (Musaiger A. et al. 1990), Canada (Page, B. D.et al. 1993 ) and USA (Allen, H.et al 1989 ).
Polyethylene terephthalate (PET) is the material most commonly used to make the clear plastic bottles in which bottled water is sold.The contents of the PET bottle, and the temperature at which it is stored, both appear to influence the rate and magnitude of leaching of organic and inorganic compounds from pet bottle (Peter Schmida.et al 2008).Several studies have shown the presence of compounds in bottled water, in non negligible concentrations.Mutsuga M. et al (Mutsuga M.et al.2006) reported the acetaldehyde forming during the polymerization reaction and the hot step process in the bottle water manufacture.Farhoodi et al. (Farhoodi et al. 2008) studied the interaction of incubation time with storage temperature on the leaching of DEHP from PET bottles.Cristina Bach et al. (Cristina Bach et al.2009) tested water bottles after exposure to extreme conditions of high temperature and UV radiation to accelerate the possible migration of substances.
In sunlight exposure tests, Wegelin et al. (Wegelin et al. 2001) have shown that PET degradation products such as terephthalate monomers and dimers are primarily formed at the surface of the bottles.Peter Schmid et al. (Peter Schmid et al. 2008) sought to determine whether solar water disinfection (SODIS) would promote leaching of phthalates into water in PET bottles.SODIS is a technique used in developing countries to disinfect water by incubating water in PET bottles in direct sunlight.After 17 hr of incubation in direct sunlight, maximum concentrations of di(2-ethylhexyl)adipate and DEHP were 0.046 and 0.71 µg/L, respectively.From the literature on leaching of PET it becomes evident that time is a dominant factor governing the release of organic substances (Nawrocki, J.et al. 2002).
During the five years, there has been a considerable increase in the consumption of bottled water in Kurdistan region (north of Iraq), especially in the summer .According to the ministry of industry in 2010, 27 bottled water companies in Kurdistan region produced about 1.692 x 10 9 L of bottled water.Bottled water is also imported from Turkey country.The biggest bottled water production company in Kurdistan region is Life Company which produces 27 * 10 6 liter bottled water per year.The main source of bottled water sold in Kurdistan region is from springs, wells and surface water.Temperatures in Kurdistan region exceed 45°C at the summer time and the storing of bottled water in the car or out the of markets is a very common practice.Therefore, it is necessary to conduct the effect of temperature on the physicochemical properties of the bottled water.On the other hand, it is quite often for people to use the plastic bottled water outdoor and some markets leave it under sun light.Therefore, it is very important to understand whether nature sunlight may affect the quality of this bottled water.This paper presents the results of a study aimed at evaluating the physicochemical water quality of locally produced bottled water in Kurdistan region.Comparisons of the results to standards as well as to the reported label values are presented.The effects of sunlight and temperature for 30 days on the quality on the Life bottled water have been carried out .theI.R spectra of the PET bottles were performed to deduce the nature and purity of the plastic, used as a packed bottled.

MATERIALS AND METHODS
Reagents and Solutions: Analytical reagent grade chemicals were employed for the preparation of all solutions.Freshly prepared deionized water was used in the experiments.
Bottled water sample: Sixteen brands of bottled water were collected from different supermarkets within three cities (Erbil, Sulaimanya and Duhok) in Kurdistan region.Each brand name and origin are given in Table 1.  ) in water was determined by Dionex ICS-1000 from USA connected with conductivity detector.The mobile phase for cationic measurement is 20 mM of methanelsulfonic acid and for anionic measurement are 3.5 mM Na 2 CO 3 + 1.0 mM NaHCO 3 .Bs-11, k109050.A calibration curve was prepared for each anion using aliquots anion concentrations higher than detection limits.The detection limits of F -, Cl

pH values:
The pH values for all samples fluctuated between 7.0 to 8.1 .The pH values showed remarkable differences between pH determined and that reported on the labels (Table 1).The limit of pH value for drinking water according to IBWA is specified as 6.5 to 8.5.The pH shows slightly alkaline trend.Generally pH of water is influenced by geology of catchments area and buffering capacity of water.Electrical conductivity: The electrical conductivity results of bottled water samples showed short variation, which ranged from 309 to 361 µS/cm, (Table 1) all samples are within the IBWA limit for bottled water.Only one brand of water sample reported the EC value in its label.

Total Dissolved Solids (TDS):
The TDS values of samples varied between 155 and 188 mg L -1 .These values were within the WHO and IBWA standards.
As it is denoted in Table 1 there are remarkable differences between TDS values measured in this work with that of reported on the labels.

Chloride:
The permissible limit of chloride in bottled water is 250 mg L -1 .The values of chloride determined in bottled water samples were very low (between 5.093 and 8.837 mg L -1 ), within the permissible limit and different from that reported on the label.
Fluoride: Fluoride ions were found in all brands at concentrations between 0.010 and 0.281 mg.L 1 .Fluoride in bottled water may come from natural sources.Fluoride exceeded all bottled water samples are within the international guidelines of bottled water and greater than that reported on the labels.
Ammonia: One bottled water brand contained ammonia at 0.0012 mg L -1 concentration.Ammonia enters water from fertilizer runoff, leaching septic tanks, and erosion of natural deposits.Units at 25°C mg L -1 mg L -1 mg L -1 mg L -1 mg L -1 6.5 -9.5 1.000 250 -50 1.5 6.5 -8.5 500 250 250 44 0.8-2.4* Guideline value; ** Standard of quality Nitrates: Nitrate was found in all brands, at the concentrations between 0.952 to 6.247 mg L -1 .The nitrate concentration detected in all bottled samples are less than the minimum permissible limits (44 mg L -1 ) .Determined concentration of Nitrate in all brand bottled water so greater than that reported on the bottles .Six brands of bottled water showed the concentrations of chloride ions greater than that recorded on the labels.While five brands not reported amount of nitrite on labels.

Sulphates:
The sulphate levels varied between 11.360 and 21.43 mg L -1 1.These concentrations were within the ranges of IBWA bottled water standards (250 mg L -1 ).Sulphate exceeded all bottled water samples are greater than that reported on the labels.Chemical Oxygen Demand: COD is used as a discharge standard parameter to deduce the amount of dissolved organic compounds in water (Baohui Jin et al. 2004).In the present work COD are measured to indicate the amount of dissolved organic compounds in bottled water under different condition.The observed COD values in all the bottled water samples are varying from 6.284 to 11.358 mg L -1 .The permissible limit of COD for drinking water is 255 mg L -1 .Hence the observed COD values in all the samples are well within the desirable limit.The COD values were reported only on one brand of bottles samples.
IR spectra of bottled: IR spectra of all brands plastic bottled were performed to characterize whether the plastic bottled made from PEF or other polyester.The characteristics bands of IR spectrum of bottled samples indicate that all plastic are made from PET the (Urban, M.W. 1996).Tables 4 shows the wave number and assignment of IR spectrum of plastic bottle of Life brand .As clearly seen in IR spectrum (Fig 2), all bands within the region 1000 to 1500 cm-, interacted and appear as a broad band .This may be due to chemical additives present in the PET bottled samples.   and NH 4 + with increasing of sunlight exposure time.While the values of pH, Cl - and F -were decreased with increasing of sunlight exposure time.The increasing of EC (from 342 to 360 µs/cm) and TDS (from 171 to 180 mg L-1) with sunlight exposing may be due to the leaching of ions and metals from plastic bottled to the water.Leaching of metals from plastic bottles to the water was evaluated by many researchers.(zeljka Fiket et al. 2007) ,(Helle Rusz et al. 2006 ).On the other hand, the increasing of EC and TDS were companied by increasing of ions concentration with sunlight exposure time.As clearly indicated by the results in Fig. 3, the sunlight radiation was lead to variation of COD amount of bottled water (increase from 342 to 460 mg L -1 during 30 days).Such variation can be attributed to the leaching of the compounds produced from the photodegradation of PET by sunlight (Wegelin et al. 2001).Outdoor sunlight irradiation has been studied for its effects on organic compounds leaching.Schmid et al (Schmid et al. 2008) reported the leaching of 0.046 and 0.71 µg/L of di(2ethylhexyl)adipate and di(2-ethylhexyl)adipate DEHP respectively ,after 17 hr of incubation in direct sunlight.The data reveal that, over the 30-day exposures test, the concentration of NO 3 -, SO 4 -2 and NH 4 + increased from 3.316 to 3.741, 19.412 to 19.791 and N.D to 0.0129 mg L -1 respectively.These observations can be interpreted on the basis of the organic compounds in water (original organic compound in water and photodegradation byproduct leached from bottle) were converted to inorganic species (CO 2 , NO 3 -, SO 4 -2 and NH 4 + ) by sunlight (Sulaiman Gafar 2010 ).The decreasing of chloride ions (from 8.610 to 8.433 mg L -1 ) and fluoride ions (from 0.173 to 0.157 mg L -1 ) in bottled water sample can be suggested by occurring the chlorination and fluorination reaction during the sunlight exposure process.This suggestion is in agreement with the detection of toxic byproducts such as chloroform, bromodichloromethane, and haloacetic acids in bottled water by Beglen,T.H et al. (Beglen,T.H et al. 1989).The pH value of the bottled water was decreased from 7.8 to 7.0 when exposed to sunlight for 30 days.This can be ascribed to the oxidation of organic compounds through the photodegradation by sunlight which producing such compounds like phthalate ester (Monarca et al. 1994), haloacetic (Beglen,T.H et al. 1989 )acids and acetaldehyde (Lo Russoet al. 1985).
Table6: effect of temperature on physicochemical properties of water samples.
Temperature Time(days) Cond.µs/cm   6.The changing trend of the physicochemical properties values with increasing of temperature can be ascribed to the occurring of plastic thermal degradation.
Thermal degradation is temperature dependent and it occurs more rapidly at higher temperatures (Lin, J. et at. 2000)..This means that thermal degradation did not occurs during the storage of bottled water under this temperature.While at the temperature above 25 o C, the values of COD increased with increasing the temperature and the time of storage .These results suggest that hightemperature storage enhances organic and inorganic compounds leaching over a period of time.Temperature influences the leaching both of organic and of inorganic compound have been reported by Pinto B et al. (2009) and Franck Villain (1995).

Conclusion:
On the bases of our results we can conclude the following: 1-The concentration levels of various physiochemical parameters in the studied bottled water types did not exceeded the international guidelines for drinking water.2-Bottled water produced in Kurdistan region was characterized by low Cl -and NH4 + values compared to national and WHO guidelines for drinking water.3-The information reported on the label dose not represent the real values of physicochemical properties.4-Slight variations of physiochemical properties were found between the bottled water brands.5-The storage of bottled water in condition above 35 o C or exposure to sunlight leads to increasing the values of (Ec , TDS, COD, NO 3 -, SO 4 -2 , NH 4 + ) and decreasing the values of (pH, F -and Cl -) ,due to acceleration of organic and inorganic compounds leaching from bottled to the content water .
Effect of Temperature: Thermal degradation of polymers is 'molecular deterioration as a result of overheating'.At high temperatures the components of the long chain backbone of the polymer can begin to separate (molecular scission) and react with one another to change the properties of the polymer.Several experiments were carried out under different temperature condition for 30 days to deduce the effect of temperature on the physicochemical properties values of bottled water.During 30 days of sample storage under 25 o C, no significant change of physicochemical properties was observed .While, when the temperature raised to 35 o C all physicochemical properties values started change with increasing the time of storage .This increasing was observed more remarkably when the temperature raised to 45 o , 55o and 65 o C as shown in Table

Table 1 :
brand name, city of production and Physicochemical properties of bottled water samples

µs/cm 188 (-) 7.8 (7.9) 6.519 ( -) 0.199 (0.15 ) 8.492 (5.51 ) 0.952 (-) 12.293 ( -) N.D ( <0.05)
*values measured in this work: **values reported on label of bottled water: *** N.D: not detected Analysis and Methods: Prior to analysis, all instruments were calibrated.pH was measured by using pH -meter (HANNA instrument model PHB) with combined electrode.EC was determined by conductivity meter Hi8314.IR Spectra were performed by IR 300 spectrometer from USA.Samples were prepared mechanically by cutting a part of the stretched PET bottle.The concentration of ions (Cl -, F -, NO 3 -,SO 4 -2 and NH 4 + Table 3).Additionally the results of the physicochemical properties measured in this work compared with the reported label values for all bottled water samples (Table.1).

Table 2 :
The Mean Intensity of sunlight and Temperature in Erbil city during 5 th of July to 5 th of August /2010 at the time interval 0 am to 5 pm

Table 3 :
International standards related bottled water quality

Table 4 :
Band assignments for IR spectrum of PET bottle of Life brand

Table 5
Effect of sunlight on physicochemical properties of water samples