Sustainability of good health depends upon purity of water. The toxic heavy metals presence in water bodies arises from the discharge of untreated effluents or dumping of solid waste containing heavy metal salts. Leaching of these heavy metals into water bodies causes various health hazards. Urbanization of rural areas has led to contamination of ground as well as surface water rendering it not suitable for human consumption. Vasai was selected for the study as it is rapidly developing area in terms of urbanization as well as industrialization. The study involved determination of heavy metal contamination in local water bodies’ i.e. three ground water sources Killa Road Koliwada (Site A), Bhaskar Alley (Site B), Palmar wadi (Site C) and three surface water sources Papdi Talav (Site D),Tamtalav (Site E) & Dhuri Talav (Site F) respectively. The water samples were tested for contamination of heavy metals like Lead (Pb), Cadmium (Cd), Chromium (Cr), Zinc (Zn), Iron (Fe) and Copper (Cu) using Atomic Absorption Spectroscopy. Comparison of the results with Indian Standard for Drinking Water (IS 10500: 1991) showed that ground waters were more contaminated than surface waters. Site A, B and C showed high level of Lead and Cadmium as compared to permissible ranges. Site D showed high levels of Iron and Copper, whereas Site F was found to be have lower Iron concentration. The results showed that urbanization in the Vasai region has had a deep impact on water bodies and sustainable development should be implemented for future developmental planning.
INTRODUCTION
Water is one of the most essentials that supports all forms of plant and animal life on this planet. The two main natural sources of drinking water are; surface water such as freshwater, lakes, streams, rivers etc. and groundwater such as borehole water and well water 1,6. Only a small fraction (about 2.5%) of earth’s water is fresh and suitable for human consumption.
About 13% of this division is groundwater; an important source of drinking water for many people worldwide 4. In rural and small communities groundwater serves as the only source of drinking water. According to UNESCO, more than 50% of the world population depends on groundwater for domestic use 3. One of the most important aspects in groundwater studies and concerns with respect to human health is to make it mandatory to analyze the drinking water prior to consumption.
Over the years, groundwater pollution due to contaminants leaking from the disposal sites is a big problem in many countries. Industries such as ceramic, painting, glass, mining, battery and manufacturing are considered the main sources of heavy metals in local water streams, which eventually contaminate groundwater with heavy metals. Landfill leachates site is another source of heavy metal contamination in groundwater 5. Increase in human activities such as industrialization coupled with over population and increase in ambient temperature are among other factors that have become major environmental issues in recent years.
Nonpoint sources as well as point sources are major reasons for surface water heavy metal contamination. Nonpoint sources include city sewage and agricultural run-off, which has fertilizers and pesticides fortified with various heavy metals. Point source pollution of surface water in semi-urban area mostly consist of small-scale industries 9.
Exposure to very low levels of elements such as lead, cadmium and mercury have been shown to have a cumulative effects on humans since there is no homeostatic mechanism that can operate to regulate the levels of these toxic substances 2. The increase of industrial activities has intensified environmental pollution problems and the deterioration of several aquatic ecosystems with the accumulation of metals in biota. Although some trace metals at low concentrations are essential to life, at high concentrations, may become hazardous. High concentrations of trace elements are dangerous because they tend to bio-accumulate resulting in heavy metal poisoning. However, at higher concentrations they can lead to poisoning. Heavy metal poisoning could result, for instance, from drinking-water contamination (e.g. lead pipes), high ambient air concentrations near emission sources, or intake via the food chain. Heavy metals such as Pb, Cd, Cr, Ni, Zn, Cu and Fe are not biodegradable and their existence in water bodies causes bioaccumulation in living organisms, which leads to several health problems in animals, plants and human beings such as cancer, kidney failure, metabolic acidosis, oral ulcers, renal failure and damage in stomachs of the rodents 7.Many trace metals considered as serious pollutants of aquatic ecosystems endangering rare indigenous species like Fenneropenaeus indicus and Harpadon nehereus from Arnala Beach and Vasai Creek respectively 8.
Ground and surface water sources are primarily the most depended upon sources of water in the regions of Vasai as opposed to paid water delivered using tankers. Over the years rapid development has occurred in this region, it has become necessary to analyze the portability of drinking water.
MATERIALS AND METHOD
All the chemicals and reagents used were Analytical grade and were purchased from Merck, Germany. Standards were prepared using 1000 ppm standards stock solutions of Lead, Chromium, Cadmium, Zinc, Iron & Copper.
Sample Collection and location
The ground water samples were collected from bore wells and lakes in the study area in the month of February 2018. The sampling site are given as in Table1. Standard method was adapted for the analysis of heavy metal. Deionised water used for the preparation of solution throughout the study. The samples were collected in clean 1 liter polythene bottles. All the bottles were washed with dilute acid followed by rinsing it with deionised water and dried prior to use. One water sample each from the six locations were collected.
The samples were filtered using Whatman filter paper No. 1. To make sure the removal of organic impurities from the samples and thus prevent interference in analysis the samples were digestion with nitric acid. 2 mL of concentrated HNO3 and 5 mL of concentrated HCl were added to 50 ml of water in an evaporating dish. The mixture was evaporated to half of its volume on a hot plate after which it was allowed to cool and then filtered.
Save your time!
We can take care of your essay
- Proper editing and formatting
- Free revision, title page, and bibliography
- Flexible prices and money-back guarantee
Sample Analysis
The analysis of the digested samples for presence of heavy metals (Pb, Cd, Cr, Zn, Fe & Cu) was carried out using atomic absorption spectrophotometer (AAS, Agilent AA-240 FS). The calibration plot method was used for analysis.
Air-acetylene flame was the flame used and hollow cathode lamp of wavelength corresponding the elements were 217 nm, 357.9 nm, 228.8 nm, 213.9 nm, 248.3 nm & 324.8 nm for Lead, Chromium, Cadmium, Zinc, Iron & Copper .
RESULTS AND DISCUSSION
The study was focused on analysis of heavy metal contamination in ground and surface water using Atomic Absorption Spectroscopy. The locations chosen for this project were precisely selected because these are considered as potable drinking water sources by the locals of Vasai region.
Lead
It was found that ground water sources, namely Sites A, B and C had Lead concentration above the permissible range i.e. above 0.05 ppm. The most probable cause for high levels of Lead could be the landfills at the outskirts of the town. Also other possible reason for lead contaminating the ground water could be lead based paints used to paint boats as well as bayous and roads. Recent trend of placement of synthetic roofing with lead based adhesives is a speculative cause of lead contamination.
In comparison to ground water only Site D surface water showed lead contamination. This could be due to perpetual Ganapati Visarjan for over 4 decades and the use of Lead based paints to colour the statues.
Cadmium
Cadmium was found in all ground water sites; A, B and C in heavy concentrations. Presence of cadmium in these samples can lead to speculation that due to agriculture being the oldest occupation in Vasai region, the use of cadmium based pesticides and fungicides could be reason for high Cadmium concentrations. All three Sites of Surface water showed only trace amounts of Cadmium.
Chromium
Like cadmium, chromium a carcinogenic heavy metal was found in ground waters of Site A, B and C. The sole reason for the presence of this metal could be the presence of landfills near the Koliwada Road where a lot of electronic waste is being discarded on a daily basis. Since the landfill is not managed or monitored with precision the chances of leaching become higher possibly contaminating the ground water. Surface water at the chosen three Sites showed no chromium contamination.
Zinc
Zinc was found to be low in the water sources both ground as well as surface than desired levels of 5 ppm. This could be one of the leading problems for increase in frequency of birth defects along with other zinc deficiency problems.
Iron
Site A and Site B for ground water sources and Site D for surface water source showed iron contamination above permissible range of 1 ppm. The major reason for iron contamination could be seepage of sewage waste along with rusted pipes from old constructions of heritage buildings and very old storage tanks. On the other hand Site F showed dangerously low levels of iron which could be a cause for concern.
Copper
Site A in ground water sources and Site D and F in surface water sources showed high levels of copper contamination of 0.07 ppm, 0.094 ppm and 0.091 ppm respectively. The majority of copper contamination could occur due to construction work debris that are discarded without a thought. There are many active sites under construction as a part of developmental plan of Vasai region which could narrow down the copper contamination sources.
CONCLUSION
The result shows that ground and surface water quality assessment helps to identify if the water is safe for human consumption. The minimum and maximum trace metals concentrations in different site A, B & C for, Pb, Cd, Cr, Zn, Fe & Cu were (0.1437 ppm, 0.0812 ppm, 0.0039 ppm, 2.768 ppm, 1.5083 ppm & 0.7191 ppm) , (0.0536 ppm, 0.0491 ppm, 0.0216 ppm, 1.8326 ppm, 1.7219 ppm & 0.063 ppm) & (0.2130 ppm , 0.0921 ppm, 0.5130 ppm, 1.003 ppm, 0.098 ppm & 0.0419 ppm) respectively. Whereas, The minimum and maximum trace metals concentrations in different site D, E & F for, Pb, Cd, Cr, Zn, Fe & Cu were (0.0313 ppm, 0.0021 ppm, 0.0069 ppm, 1.0863 ppm, 1.32 ppm & 0.0943 ppm), (0.0019 ppm, 0.0013 ppm, 0.0006 ppm, 0.0561 ppm, 0.341 ppm & 0.0043 ppm) & (0.0023 ppm, 0.0006 ppm, 0.0024 ppm, 0.0421 ppm, 0.0031 ppm & 0.0912 ppm) respectively. Heavy metals like Pb, Zn & Fe exceeded permissible limits according to IS 10500: 1991 standards for drinking water in sampled bore wells and surface water in the Vasai region. It is recommended to use some kind of inexpensive treatment to reduce the levels of heavy metals in areas supplying water directly to consumers without any treatment. From the obtained results it is evident that, at present the metal ion concentration is not at the levels which could be harmful for humans. But still the study clearly points out that the concentrations of toxic metals are present in slight excess in some locations. It indicates precautionary measures should be immediately taken to avoid the consequences.
Stuck on your essay?
