Lithium content in potable water , surface water , ground water , and mineral water on the territory of Republic of Macedonia

The aim of this study was to determine lithium concentration in potable water, surface water, ground, and mineral water on the territory of the Republic of Macedonia. Water samples were collected from water bodies such as multiple public water supply systems located in 13 cities, wells boreholes located in 12 areas, lakes and rivers located in three different areas. Determination of lithium concentration in potable water, surface water was performed by the technique of inductively coupled plasmamass spectrometry, while in ground water samples from wells boreholes and mineral waters with the technique of ion chromatography. The research shows that lithium concentration in potable water ranging from 0.1 to 5.2 μg/L; in surface water from 0.5 to 15.0 μg/L; ground water from wells boreholes from 16.0 to 49.1 μg/L and mineral water from 125.2 to 484.9 μg/L. Obtained values are in accordance with the relevant international values for the lithium content in water.


INTRODUCTION
Lithium is one of the most important trace elements for the functioning of the human organism.Mainly in the human body is inserted through the food of plant origin (cereals, nuts, vegetables) and water.Surveys conducted by Weiner [1] for the lithium intake in our organism, show that the main part of the lithium intake is inserted through cereals and vegetables 430 and 2900 μg/day, while through food from animal origin in our body are inserted insignifi cant concentration (2.5 μg/day).
As a result, of the importance that lithium has on the functioning of the human body, scientists [2] found that recomm ended daily dietary intake of lithium (recommended dietary allowance) for adults with an average body mass of 70 kg is 1 mg/day, which is equivalent to 14.3 μg/kg body mass.The US Environmental Protection Agency established standards for daily intake of lithium which for an adult, weight of 70 kg ranging from 650 to 3100 μg. [3]This concentration of lithium could be provided with food and water intake which contain adequate concentrations of lithium.
Lithium from food or water in the form of soluble salts in the body is being completely absorbed in the gastrointestinal tract (small intestinum) trough Na + channels.Absorbed lithium almost equally is being distributed in the body fl uids with little difference between the extra cellular and intracellular fl uid.Lithium excretion of the body is carried out through kidneys.According to Hager et al., [4] after the autopsy in men and women who do not have any hetero anamnesis data of prior therapy with lithium preparations, the presence of lithium was found in the following organs: Cerebellum, cerebrum, kidney, thyroid, pancreas, lungs, and bones.From the obtained results can be concluded that the distribution of lithium is greater in women's organs than in men, except in the pancreas.During embryogenesis, the concentration of lithium in the internal organs reaches a maximum concentration in the fi rst trimester of gestation, with a gradual decline to the end of the pregnancy. [5]as well as increased transport of folic acid and vitamin B12 in L1210 cells. [6]Biological activity of lithium is due to the powerful polarization feature which is a result of its small ionic radius.Lithium can replace sodium, potassium, magnesium and calcium ions from the enzymes cofactors. [5]According to Ohgami et al. [7] the luck of lithium in the body leads to a change in people's behavior and increased aggression.
Lithium as an element which in nature is found in soil, primary in the clay fraction, [8] potable water, surface water, mineral water, ground water and marine waters as well.
Because the primary source of lithium in humans are water and food, the objective of our research was determination of lithium content in potable water, surface water, ground water from wells boreholes and mineral water on the territory of the Republic of Macedonia, since such data have not been available so far.

Water sampling
The samples of potable water from public water supply systems were investigated, as well as surface water, ground water from wells boreholes and mineral water taken from the territory of the Republic of Macedonia [Figure 1].Determination of the concentration of lithium was performed in 30 samples of potable water from multiple public water supply systems/network in the Republic of Macedonia (Skopje, Tetovo, Ohrid, Sveti Nikole, Bitola, Prilep, Strumica, Shtip, Radovish, Kriva Palanka, Kavadarci, Gevgelija and Veles).Determination of lithium concentration in surface water was done on 15 samples taken from several measuring points from the Ohrid Lake, river Lepenec and river Vardar (Gevgelija).The ground water samples from wells boreholes, 35 in total were taken from the territory: Skopje, Kavadarci, Radovish, Kumanovo, Bitola, Sveti Nikole, Prilep, Strumica and Negotino.
The proportion of different water samples in which content of lithium was determined is shown in the following Figure 2.

Analytical methods for determination
Determination of the concentration of lithium in potable water and surface water was performed with the technique of inductively coupled plasma-mass spectrometry.The NexION® 350D ICP-MS features a dual-channel Universal Cell as well the ability to use Dynamic Reaction Cell™ technology, giving analysts the fl exibility to choose Kinetic Energy Discrimination (KED) and/ or the use of a scanning quadrupole in the Dynamic Reaction Cell.These capabilities make it the ideal solution for biomonitoring applications.The limit of detection of lithium with this instrument is 0.05 μg/L.Concentration of lithium in the ground water from wells boreholes and surface water were performed with the technique of ion chromatography with conductivity detector which covers the concentration areas for this type of waters.The performance of this instrument is given in Table 1.

RESULTS AND DISCUSSION
Purpose of our investigation is to determine the concentration of lithium in potable water, surface water, ground water from wells boreholes and mineral water on the territory of the Republic of Macedonia.The results of the tests are given in Tables 2-5.Regulations for the water quality in the Republic of Macedonia provide no lithium content data.Therefore, our results were compared with literature data.
Lithium was found in all analyzed water samples from the territory of Republic of Macedonia.Its concentrations depended on the type of water sample, which was analyzed [Table 6].The heterogeneity of the results in the general research with a high coeffi cient of variation values implied that differences in the location and period of sampling had a major infl uence on the lithium content.
Research shows that concentration of lithium in the potable water from public water supply systems in the Republic of Macedonia ranging from 0.11 to 5.20 μg/L [Table 2].In some regions of the world, [7,9] in order to increase the daily intake of lithium in human nutrition, lithium is added as a supplement in the potable water (tap water), with the fi nal concentration of lithium in water of 170 μg/L.Low lithium concentration in potable water from multiple public water supply systems from the network in the Republic of Macedonia points to the possibility for a beginning of the enrichment of Macedonian potable water with lithium.
Determination of the concentration of lithium was performed in 30 samples of potable water from multiple public water supply systems/ network in the Republic of Macedonia.By calculating the average values of the lithium concentration according to the location the follow hierarchical lithium concentration gradient is obtained Skopje 2.84 μg/L, Kavadarci 1.81 μg/L, Sveti Nikole 1.56 μg/L, Gevgelija 1.33 μg/L, Shtip 1.00 μg/L, Strumica 0.67 μg/L, Tetovo 0.49 μg/L, International Journal of Medicine and Public Health | Jul-Sep 2014 | Vol 4 | Issue 3

Figure 1 :
Figure 1: Distribution of sampling sites from the territory of Republic of Macedonia

Figure 2 :
Figure 2: Percentage of the types of water in which is determined the concentration of lithium

Table 1 : Instrumental condition for determination of lithium with IC
IC = Ion chromatography

Table 2 : Results of determination of lithium in public water supply systems in the republic of macedonia (μg/L)
Ohrid 0.18 μg/L and Veles 0.15 μg/L.If the territory of Republic of Macedonia is separated with river Vardar on the west and east part the estimated lithium concentrations of potable water are little bit higher in the east part (1.69 μg/L >1.34 μg/L).

Table 3 .
Lithium concentrations in surface water varied from 0.53 to 15.03 μg/L.Highest average lithium concentration was obtained on the measuring points at river Vardar near Gevgelija of 13.09 μg/L and the lowest average lithium concentration of 1.07 μg/L was obtained in the measuring points at Ohrid Lake.