Development Team

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Environmental Sciences

Environmental Microbiology & Biotechnology Module 09: Major Water Borne Diseases Part III Paper No: 15Environmental Microbiology & Biotechnology

Module: 09 Major Water Borne Diseases Part III

Development Team

Principal Investigator

&

Co- Principal Investigator

Prof. R.K. Kohli

Prof. V.K. Garg &Prof.AshokDhawan Central University of Punjab, Bathinda

Paper Coordinator

Dr Babita Khosla

Mahrashi Dayanand University, Rohtak

Content Writer

Dr. Sunil Mittal,

Central University of Punjab, Bathinda

Content Reviewer Dr Anil Mantha

Central University of Punjab, Bathinda

Anchor Institute Central University of Punjab

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Environmental Microbiology & Biotechnology Module 09: Major Water Borne Diseases Part III

Description of Module

Subject Name Environmental Sciences

Paper Name Environmental Microbiology & Biotechnology Module

Name/Title Major Water Borne Diseases Part III Module Id EVS/EP-XV/09

Pre-requisites

Objectives To lean about water related diseases

Keywords Organic contaminants, Inorganic Contaminants, Radiological contaminants

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Environmental Microbiology & Biotechnology Module 09: Major Water Borne Diseases Part III Module 09 : Water borne diseases III

9.1 Introduction: Chemical contamination of water 9.2 Major types of chemical contaminants

9.2.1 Organic contaminants

9.2.1.1 Agricultural Chemicals 9.2.1.2 Oil and Petrochemicals 9.2.2 Inorganic Contaminants

9.2.2.1 Arsenic 9.2.2.2 Cadmium 9.2.2.3 Mercury 9.2.2.4 Nitrate 9.2.2.5 Iodine 9.2.2.6 Fluoride 9.2.3 Radiological contaminants

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Environmental Microbiology & Biotechnology Module 09: Major Water Borne Diseases Part III 9.1 Introduction: Chemical contamination of water

Microbial contamination of water is in prime focus among all types of water contamination.

But, last few decades, chemical contamination of water also got significant attention due to their probable adverse health impacts. Chemical contamination of surface or groundwater is resultant of natural or anthropogenic activities. A numbers of potentially harmful chemical contaminants have been identified in drinking-water which are usually present in extremely low concentrations. Pesticides, fertilizers, metals/heavy metals, organic compounds and anions are the major chemical contaminants in water. More than 200 chemical constituents have been documented in groundwater alone. Agriculture chemicals, urban runoff/storm water and municipal point sources are the largest pollution sources of surface water and are responsible for groundwater pollution through leeching process. Chemical contaminants are associated with diabetes, hypertension, nervous disorder, cardiovascular problem, cancer etc.

and have impacts on every part or system of human being and other living beings. The complete list of chemical contaminants with their sources and health effects are enlisted in Table 3.2, 3.3 and 3.4.

9.2 Major types of chemical contaminants include:

I. Organic contaminants II. Inorganic contaminants III. Radiological contaminants

9.2.1 Organic contaminants mainly include a. Agricultural Chemicals

b. Oil and Petrochemicals

9.2.1.1 Agricultural Chemicals

Agriculture chemicals are one of the major sources of chemical contamination in water.

Agriculture is both the cause and victim of water pollution. It causes water pollution through discharge of pollutants and sediment to surface/groundwater. Use of wastewater and polluted surface and groundwater, contaminates crops and transmit diseases to consumers

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and farm workers. The major classes of agricultural chemicals are given in Table 3.1 on the basis of their applications.

Table 3.1: Agricultural chemicals are classified as follows on the basis of application:

S.

No

Types of Agricultural

Chemicals

Description

1 Insecticides Control harmful insect pests that damage field crops.

2 Fungicides Agents to control fungal diseases in field crops.

3 Insect-

fungicides Control harmful insect pests and diseases together in field crops.

4 Herbicides Controls weeds

5 Rodenticides Agents to control rats and other rodents 6 Plant growth

regulators Agents to promote or inhibit the growth of field crops.

7 Attractants Agents that attract mainly harmful insect pests by odor or other means.

8 Repellents

Agents that have repellent action on harmful mammals and birds that damage field crops.

9

Spreaders Agents that are mixed with other agricultural chemicals to enhance the adherence of these chemicals.

10 Fertilizers Used to enhance crops growth and production

 Nitrate, chloride, heavy metals, organic pollutants, etc. released from fertilizers/pesticides enhances the level of contaminants in groundwater due to leaching through soil and poses threats to public health.

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 Runoff of fertilizers and pesticides to surface waters causes dysfunction of ecological system by the loss of top predators due to growth inhibition and reproductive failure.

Organochlorines and organophosphates are two major classes of pesticides, which are extremely toxic

 Organochlorine pesticides -. DDT, benzene hexachloride, toxaphene, methoxychlor, aldrin, dieldrin, chlordane, mirex, kepone, and lindane are the major chemicals under organochlorine pesticides. Most of the harmful organochlorine pesticides are already banned by Environmental Protection Agency in most of the countries. But, still, they are harmful due to their persistence nature.

 Organophosphates pesticides - commonly used organophosphates are chlorpyrifos, parathion, methyl parathion, malathion, diazinon, phosmet, dichlorvos, fenitrothion, azamethiphos tetrachlorvinphos and azinphos-methyl.

Pesticides damages endocrine, immune and detoxification systems of the body. Pesticides cannot be completely detoxified by the body and therefore accumulate in the tissues, where they continue to cause dysfunction and disease.

9.2.1.2 Oil and Petrochemicals

 Petrochemicals can be defined as a large group of chemicals derived from petroleum and natural gas and are used for a variety of chemical purposes. The pollution of oil and petrochemical in water cause serious health concern in aquatic and living beings.

 Gasoline, diesel and benzene and others petrochemicals may contaminate the water supply by leakage from underground storage tanks.

 Methyl tertiary butyl ether (MTBE) and benzene are known carcinogen and possess chronic toxicity to human and other living beings.

Petrochemicals give rise to a number of organic contaminants. The chief organic contaminants and their health impacts are mentioned in Table 3.2.

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Environmental Microbiology & Biotechnology Module 09: Major Water Borne Diseases Part III Table 3.2: Organic contaminants and related health risk

Contaminant Sources to groundwater Potential health and other effects Volatile organic compounds Solvents, dyes, plastics

manufactures, rubbers, crude oil, inks, polishes, insecticides, spot removers

varnishes, paints,

disinfectants, preservatives,

gasoline products,

pharmaceuticals etc.

Anemia, skin irritation, blurred vision, weight loss, respiratory tract irritation, gastrointestinal disorder, damage to the nervous system and cancer & liver damage.

Pesticides Fungicides, insecticides, rodenticides, herbicides, and algicides.

Gastrointestinal disturbance, headaches, poisoning, numbness, weakness and cancer. Destroys thyroid, reproductive system, liver, kidneys and nervous system.

Plasticizers, chlorinated solvents, benzo[a]pyrene and dioxin

Improper waste disposal, leakage from storage tank, leaching runoff, pesticides and industrial runoff.

Damages nervous and reproductive systems, stomach, kidney, and liver. Also known to cause cancer.

Benzene, Benzo(a)pyrene (PAHs), Carbofuran, Carbon Tetrachloride, Endrin, Heptachlor, Lindane, Methoxychlor, Dioxins, Polychlorinated

biphenyls Trichloroethylene (PCBs), Toluene, Vinyl chloride,Heptachlor epoxide,

Discharge from industrial chemical factories, petroleum refineries, landfill, pesticides runoff

Problems with liver, stomach, reproductive system and kidneys, increased risk of cancer, reproductive difficulties

9.2.2 Inorganic contaminants

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Metal/heavy metals and anions mainly contribute to inorganic contaminants in water. Heavy metals and anions contamination in water is a serious health concern since few decades due to their probable association with various adverse health impacts like, nervous, lung, kidney, cardiovascular, skeletal diseases, etc. and various types of cancer.

Heavy metals - Arsenic (As), lead (Pb), uranium (U), mercury (Hg), cadmium (Cd) nickel (Ni) and chromium (Cr)

Anions like sulfate (SO42-), nitrate (NO3-), chlorides (Cl^-) and fluorides (F^-)

The complete list of heavy metals and major anions with their health impacts and sources are enlisted in Table 3.2.However, some important chemical like arsenic, cadmium, mercury, nitrate, iodine and fluoride and their health effects are described in detail in further sections.

9.2.2.1 Arsenic

Arsenic is a carcinogen and potential environmental hazard. Arsenic (As) has influenced human history probably more than any other element due to its toxicity. Around 70 countries and 137 million people affected by arsenic pollution. WHO describes arsenic contamination of Bangladesh’s water supply as “the largest poisoning of a population in history”.

Sources: Arsenic is released into the environment and water through both natural and anthropogenic activities.

Natural - Weathering of rocks and minerals

Anthropogenic - Pesticides, insecticides, fertilizers, fly-ash and mining practices

Form of Arsenic- Both inorganic and organic forms. Arsenite [As(III)] and arsenate [As(V)]

are the common inorganic form and As(III) is more toxic than As(V).

Mode of exposure – Mainly through ingestion of contaminated water.

Health impacts of Arsenic

Arsenicosis is a chronic illness which is implicated due to exposure of arsenic contaminated water over a long period (Fig 1a & b). It is very difficult to diagnose early symptoms of arsenicosis. Arsenic also increases the risk of cardiovascular, kidney, lung disease and certain

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types of cancer (e.g. skin, bladder and lung). Apart from this, both As (III) and As (V) inhibit pyruvate dehydrogenase. As (III) interferes with phosphorylation (citric acid cycle) reaction as a result no ATP is formed.

Figure 1: (a) and (b) Arsenic effect on skin (Arsenicosis)

(https://www.theguardian.com/global-development-professionals-network/2016/oct/18/arsenic- contamination-poisoning-bangladesh-solutions)

9.2.2.2 Cadmium

Cadmium is extremely toxic heavy metal and a carcinogenic chemical.

Sources - Discharge during the smelting of metals like zinc, lead, copper, etc. and manufacture of nickel-cadmium rechargeable batteries found in mobile phones/cordless equipment. It is also used in metal plating, some paints, plastics and fertilizers.

Mode of exposure - Cigarette smoke, ingestion of cadmium-contaminated foods. Old galvanized and new plastic (PVC) pipes are sources of cadmium in drinking water.

Health Impacts

Cadmium may affect the kidneys, lungs and bones. Itai-itai disease is a resultant of cadmium poisoning (Fig 2). The kidney is the principal organ targeted by chronic exposure to cadmium. “Itai-itai” or ouch-ouch disease was first described in post-menopausal Japanese

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women exposed to excessive levels of cadmium over their lifetimes in Jinzu River basin in Toyama, Japan.

Figure 2: Cadmium Poisoning – Itai-Itai diseases

(http://priusblack.blogspot.in/2016/10/gold-is-gone.html)

Symptoms

 Osteoporosis, osteomalacia, softening of bones and severe renal dysfunction are the primary symptoms of this disease.

 Sometimes normochromic anemia and low blood pressure.

 Average urinary cadmium level in these patients is 20-30 ìg/g-creatinine of cadmium in urine.

9.2.2.3 Mercury

Mercury is a naturally occurring element found in air, water and soil.

Mercury has three forms: (1) Elemental mercury (2) Inorganic form and (3) Organic form.

Organic form is extremely toxic.

Sources - Natural source mainly include volcanic activity. Major sources of mercury pollution are anthropogenic like mining, industrial effluents, batteries, fluorescent light bulbs, thermometers, pesticides and fungicides.

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Mode of exposure – Most toxic form of mercury is methylmercury, concentrated in the food chain. The primary medium of exposure occurs through ingestion of water and contaminated food.

Health Impacts

 Minamata disease is a result of methyl mercury poisoning in humans by ingestion of fish and shellfish exposed to methyl mercury. Minamata disease is a neurological syndrome caused by severe mercury poisoning. Symptoms include ataxia, numbness in the hands and feet, general muscle weakness, narrowing of the field of vision and damage to hearing and speech.

 Mercury exposure at high levels can harm the brain, heart, kidneys, lungs and immune system.

 Binding of mercury to cell membrane may cause the imbalance of membrane permeability to K⁺, affecting the neuronal transmission process, mental retardation and chromosomal defects.

Figure 3: The crippled hand of a Minamata disease victim (W. Eugene Smith)

(https://en.wikipedia.org/wiki/Minamata_disease)

9.2.2.4 Nitrate

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Nitrate is an inorganic compound that occurs both naturally and synthetically in the environment. Nitrate is one of the most common groundwater contaminants in rural areas.

Nitrate in groundwater originates primarily from fertilizers, septic systems and manure storage. Unavailable nitrogen from the fertilizers leaches to the groundwater in the form of nitrate. This can elevate the concentrations of nitrate above permissible levels in groundwater affecting the drinking water quality.

Nitrates cause eutrophication in water environment. Eutrophication makes the adverse condition for aquatic system and creates oxygen deficiency to aquatic organisms. The whole scheme of eutrophication is given in fig 4 & 5.

Figure 4: Scheme of Eutrophication Process

(https://www.quora.com/What-is-eutrophication)

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Figure 5: Eutrophic Lake Fig 6. Blue-baby syndrome

(http://www.lakescientist.com/eutrophication/ )

(https://sinhvienykhoa115.wordpress.com/category/chuyen-d%E1%BB%81/khac/page/5/)

Health Impacts

Methemoglobinemia - Regulation of nitrate in drinking water is very important because excess levels can cause methemoglobinemia or "blue baby" disease (Fig 6).Blue-baby syndrome usually occurs in rural areas, where the primary source of drinking water are wells.

Methemoglobinemia most often affects infants of less than six months in age.

Methemoglobinemia is the condition in the blood which causes infant cyanosis, or blue-baby syndrome. Methemoglobin is probably formed in the intestinal tract of an infant when bacteria convert the nitrate ion to nitrite ion. One nitrite molecule then reacts with two molecules of hemoglobin to form methemoglobin. This alters the form of blood protein, prevents the blood cells from absorbing oxygen and causes suffocation to the infants which may lead to death. Due to oxygen deficiency, blue and purple tinge appears on the lips of infants. So, it is named as blue baby syndrome.

Nitrate is not classified as a carcinogen, but prolonged exposure to nitrate results endogenous reduction into nitrite by nitrosation reactions and forms highly carcinogenic N-nitroso compounds in the stomach, large intestine, colon as well as bladder. N-nitroso compounds are one of the strongest known carcinogens, act systemically and can cause cancer in digestive part of body.

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Environmental Microbiology & Biotechnology Module 09: Major Water Borne Diseases Part III 9.2.2.5 Iodine

Iodine is a non-metallic trace element that is required by humans for the synthesis of thyroid hormone. Thyroid hormone is secreted by thyroid gland. Thyroid gland is a small butterfly- shaped gland in the neck. Thyroid hormone is required throughout the life for normal growth, neurological development and metabolism. The impairment of iodine level causes goiter and hypothyroidism like disorder.

Goitre

Iodine deficiency results adverse health disorders such as thyroid gland enlargement (goiter) and severe physical and mental retardation (cretinism).Goiter is swelling of the thyroid gland that causes lump formation in the front of the neck.

Symptoms:

 coughing

 a tight feeling in throat

 changes voice, such as hoarseness

 difficulty in swallowing

 difficulty in breathing

Insufficient iodine intake impairs the production of thyroid hormones, leading to a condition called hypothyroidism.

 Hypothyroidism has adverse effects in all stages of development but is most damaging to the developing brain.

 Maternal iodine deficiency during pregnancy can result in maternal and fetal hypothyroidism, as well as miscarriage, preterm birth and neurological impairments in offspring.

The recommended dietary allowance (RDA) for iodine intake is 150 micrograms (μg)/day in adults, 220 μg/day in pregnant women and 290 μg/day in breast-feeding women.

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Figure 7: Some photographs of Goiter cases

(http://generalsurgeryclinics.blogspot.in/2013/01/complications-of-multinodular-goitre.html)

9.2.2.6 Fluoride

Fluoride is the anion of fluorine. Fluoride is essential for strong and healthy teeth. But, amounts more than acceptable limits produce toxicity to the human being. Water borne fluoride is another leading cause of morbidity in many parts of the world, including the Indian sub-continent, Africa and the Far East, where concentrations of fluoride can exceed 10 mg/l. In India, around 60 million people are affected by excessive fluoride.

Sources- Granite rocks and anthropogenic sources like household products.

The major household products containing fluoride are following:

 Toothpaste (eg., sodium monofluorophosphate)

 Dietary supplements (eg., Sodium fluoride)

 Glass-etching or chrome-cleaning agents (eg., ammonium bifluoride)

 Insecticides and rodenticides (eg., Sodium fluoroacetate)

Health Impacts

 Long-term exposure to fluoride through elevated levels in drinking water leads to skeletal and dental fluorosis.

 Fluoride's suppressive effect on the thyroid is more severe when iodine is deficient.

 Fluoride-induced nephrotoxicity is kidney injury due to toxic levels of serum fluoride.

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 Fluoride also effects endocrine system. But its mechanisms remain unclear.

The other heavy metals and anions are enlisted in Table 3.3 with their health impacts and permissible limits in drinking water set by World Health Organization.

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Environmental Microbiology & Biotechnology Module 09: Major Water Borne Diseases Part III Table 3.3: Inorganic Contaminants of water and related health risk

Contaminant Maximum permissible limit

(mg/L)

Potential Health Effects from Ingestion of Water

Sources of Contaminant in Drinking Water

Antimony 0.005 Increase in blood cholesterol; Alters blood sugar level

Natural weathering, municipal waste disposal, industrial production, ceramics, glass, batteries, fireworks,

explosives and manufacturing of flame retardants.

Arsenic (Carcinogen)

0.01 Skin damage or problems (Arsenicosis), Causes acute and chronic toxicity, Effect on liver and kidney and may be increases risk of cancer

Erosion of natural deposits, Runoff from pesticides, orchards, industrial & electronics production wastes, Smelting of copper, lead and zinc ore.

Asbestos (fiber>10 micrometers)

7 Million Fibers per Litre

Increased risk of developing benign intestinal polyps

Decay of asbestos cement in water mains; erosion of natural deposits

Barium 10 Increase in blood pressure, hypertension, cardiac, gastrointestinal and neuromuscular effects.

Discharge of drilling wastes; discharge from metal refineries; erosion of natural deposits

Beryllium 0.004 Intestinal lesions, causes acute and chronic toxicity; affects lungs and bones, possible

Discharge from metal refineries and coal-burning factories, discharge from electrical, aerospace, nuclear

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carcinogen power and defense industries

Cadmium 0.003 Itai-Itai diseases, replaces zinc biochemically in the body and causes anemia, high blood pressure, liver and kidney damage. Destroys red blood cells and testicular tissue. Toxic to aquatic biota

Mainly anthropogenic activities like industrial discharge, mining waste, metal plating, water pipes, batteries, paints and pigments, plastic stabilizers and landfill leachate.

Chromium (Total)

0.05 Respiratory damage, liver and kidney damage, dermatitis, internal hemorrhaging and ulcers at high concentrations.

Discharge from steel and pulp mills; erosion of natural deposits, mineral leaching, fossil-fuel combustion, cement-plant emissions and waste incineration.

Copper 2 Short term exposure: Gastrointestinal distress Long term exposure: Liver or kidney damage Anemia in high doses. Toxic to plants and algae at high levels.

Industrial and domestic waste, metal plating mining and mineral leaching.

Cyanide (as free cyanide)

0.07 Nerve damage or thyroid problems

Damage to spleen, nerve, brain, thyroid, and liver.

Discharge from steel/metal factories; discharge from plastic and fertilizer factories

Chloride 250 Generally no impact on human but excessive high level cause hypertension and impaired sodium chloride metabolism

Fertilizers, rocks, rain water

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Fluoride 1.5 Bone disease (pain, tenderness and calcification of the bones); Children may get mottled teeth

Water additive which promotes strong teeth; erosion of natural deposits; discharge from fertilizer and aluminum factories

Lead 0.01 Affects red blood cell chemistry, probable carcinogen

Infants and children: Delays in physical or mental development, children could show slight deficits in attention span and learning abilities

Adults: Kidney problems, high blood pressure

Corrosion of household plumbing systems; erosion of natural deposits

Manganese 0.5 Comparatively harmless to animals but toxic to plants at high levels.

Sediment and rocks, mining and industrial waste

Mercury 0.006 Minamata disease , Kidney damage, nervous system disorders

Occurs in organic and inorganic forms. Enters through pesticides, mining, industrial waste, coal, electrical equipment (batteries, lamps, and switches), smelting and fossil-fuel combustion.

Nickel 0.02 Damages the heart and liver of laboratory animals exposed to large amounts over their lifetime.

Occurs naturally in soils, surface and groundwater.

Often used in alloy products, electroplating, stainless steel, mining and refining.

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Source: https://www.epa.gov/ground-water-and-drinking-water/national-primary-drinking-water-regulations xam_AlexPotonia_Q45.doc (D2755976)

Nitrate 50 Blue Baby Syndrome, shortness of breath Runoff from fertilizer use; leaching from septic tanks, sewage; erosion of natural deposits

Selenium 0.01 Hair or finger-nail loss, numbness in fingers or toes, circulatory problems. Toxic at high doses

Discharge from petroleum refineries; erosion of natural deposits; discharge from mines

Silver - Argyria, a blue-gray coloration of the eyes, skin, mucous membranes and organs in animals and humans exposed to prolonged concentrations

Product fabrication and disposal. Ore mining and processing. Frequently used in electric and electronic equipments, photography, sterling and electroplating, , alloy and solder

Sodium 200 Low sodium diet poses health risk Leaching of underground and surface deposits of salt and decomposition of various minerals. Anthropogenic activities such as de-icing and washing products Thallium 0.002 Hair loss; changes in blood; kidney, intestine, or

liver problems

Leaching from ore-processing sites; discharge from electronics, glass, and drug factories

Zinc 3 Aids in wound healing. Only high doses are toxic to humans and plants. Imparts an undesirable taste to water

Found frequently in mining areas and naturally in water.

Other sources include industrial waste, metal plating, and plumbing, and are a major component of sludge.

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Environmental Microbiology & Biotechnology Module 09: Major Water Borne Diseases Part III 9.2.3 Radiological contaminants

Radiological contaminants are chemical elements with an unbalanced number of protons and neutrons that results in emission of ionizing radiation. Examples of radiological contaminants include cesium, plutonium and uranium.

Radiological contaminants emit radiation, which cause damage to DNA and can lead to mutations and cancer. Plutonium, a radioisotope remains radioactive for a long time if it accumulates within the body and continues to damages for many years unless it is excreted.

Table 3.4: Radiological Contaminants of water and health risk Contaminant Maximum

permissible limit

Potential Health Effects from Ingestion of Water

Sources of Contaminant in Drinking Water

Uranium 30 µg/L Increased risk of cancer, kidney toxicity

Erosion of natural deposits

Alpha particles 15 picocuries per Litre

(pCi/L)

Increased risk of cancer Erosion of natural deposits of certain minerals that are radioactive and may emit a form of radiation known as alpha radiation

Beta particles and photon emitters

4 millirems per year

Increased risk of cancer Decay of natural and man-made deposits of

certain minerals that are radioactive and may emit forms of radiation known as photons and beta radiation Radium 226

and Radium 228 (combined)

5 pCi/L Increased risk of cancer Erosion of natural deposits

Preventive Measure

The most effective way of reducing contaminants in drinking water is by 1. Controlling sources of contamination

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2. Applied and fruitful research is necessary to remediate and detoxify contaminants.

3. Educate public and society to reduce source contamination and options for treatment.

4. Preventative measures such as modification of tilling methods and run-off control in agriculture.

Use of lined catchment ponds for treatment of wastes and double lined underground storage tanks can significantly reduce contamination of drinking water sources.