Water Sanitation

Water Sanitation Stella Marie M. Doyungan, Ph.D.

Water…. - most ubiquitous compound on earth - in continuous circulation, a process known as water cycle Diagram of the water cycle

Water… - essential substance Important physiological reactions within the cell that must be accomplished within water - replication of DNA - reactions that regulate and control replication - catabolic and anabolic processes

Sources of Water 1. Atmospheric water • moisture contained in clouds and precipitated as snow, sleet, • hail and rain 2. Surface water - lakes, streams, rivers and oceans 3. Ground water - springs and wells In springs, ground water reaches the surface through a rock fissure or exposed porous soil. Wells are made by sinking a shaft into the ground to penetrate the ground water level

Factors that affect quality of surface waters 1. Time of the year 2. Amount and types of discharge into the body of water Sources of pollution a. Decayed vegetation b. Fertilizers c. Other agricultural chemicals d. Sewage e. Animal wastes

Sources of contaminants in wells 1. Sewage 2. Septic tanks or associated drainage fields 2. 3. Leaks/ cracks/improperly sealed metal casings 4. Flood 5. Surface debris

Table 1. Recommended distances of wells from sources of contamination. ------------------------------------------------------------------------ Potential sources Suggested minimum distance of contamination from well (in feet)a ------------------------------------------------------------------------------------------------------------ Septic tanks 100 Sewers 100 Barnyards or feeding lots 200 Chemical disposal area 75-200 Stream 75 Landfill 200 ------------------------------------------------------------------------ aDistances may vary greatly, depending on soil conditions and amount of water present.

Uses of water in the food industry Water use in canning plants ----------------------------------------- In-plant use Total use(%) ----------------------------------------- Raw product washing 15 Product transport 10 Product preparation 10 Incorporation in product 6 Steam and water sterilization 15 of containers Container cooling 36 Plant clean-up 8 ----------------------------------------- • Formulation • 2. Conveying • 3. Cooling • 4. Steam and • boilers

Water treatment • manipulation of a water source to achieve water quality • that meets specific standards set by established regulatory • agencies

Components in the water supply that affect water quality 1. Organic components a. Naturally occurring organics • plant and animal degradation products • (fulvic and humic acids) -microbial product (geosmin- imparts a musty,earthy odor taste to water b. Synthetic organics -pesticides -polychlorinated biphenyls -halogenated methane -ethane derivatives

Components… 2. Inorganic components

Components… 3. Microorganisms - harmless and harmful microorganisms

Some common diseases transmitted by water Viruses Protozoa Poliomyelitis Giardiasis Hepatitis A Amebiasis Reovirus infection Coccidiosis Coxsackie virus infection Bacteria Cholera Shigellosis Typhoid fever Salmonellosis Enteropathogenic E.coli infection Yersinia gastroenteritis

Water purification Potable water- water that is free of disease-producing microorganisms and chemical substances deleterious to health

Principal operations employed in a municipal water-purification plant. 1.Sedimentation – removal of suspended particles 2.Coagulation - coagulates suspended materials making them easier to remove by settling

3.Filtration Common and simplest filter- bed of sand followed by a series of a bed of charcoal. Charcoal removes off-flavors color and organic solvents from water . 4.Softening: - removal of metallic ions,Ca.Mg, Fe and Mn

5. Disinfection: • Disinfectant used: • Chlorine – most common • Chloramine • Chlorine dioxide • Ozone

Table 2. Suggested concentrations of chlorine for various purposes ----------------------------------------------------------- Purpose concentration (ppm) --------------------------------------------------------------------- Drinking water 0.2 Process water 0-0.5 Cleaning 10-20 Sanitizing 100-250 Cooling (can) 0.5-10.0 Conveying water 0.5-5.0 Belt sprays 1.5-3.0 Hydro-cooling meat 5.0-200 Fish thawing 5.0-10.0 ----------------------------------------------------------------------

Table 3. Effective chlorine levels ----------------------------------------------------------------------- Microorganisms Concentration (ppm) ----------------------------------------------------------------------- Algae 2.0 Bacteria (gram-negative cells) 0.2-5.0 Spores 150-250 Mold (hyphae) 100 Spores 135-500 Viruses 0.2-3.25 -----------------------------------------------------------------------

Table 4. Effect of chlorination of cooling water on spoilage ratea ---------------------------------------------------------------------------------- Swelled cans/1000 -------------------------------------- ----- Can size Product Chlorinated Non-chlorinated cooling water cooling water ---------------------------------------------------------------------------------- 306 x 302 Vacuum-packed corn 0.46 3.44 603 x 408 Vacuum-packed corn 0.39 5.17 303 x 406 Cream-style corn 0.29 1.17 603 X 700 Cream-style corn 1.37 7.80 ------------------------------------------------------------------------------------------------------------- a from Herson and Hulland, 1980

Water Water Quality Determination Microbiological characteristics Physical characteristics Chemical characteristics

Table 5. Environmental Protection Agency National Interim Primary Drinking water regulation (1975); mg/L unless indicated ------------------------------------------------------------------------------ Constituent Maximum contaminant level ------------------------------------------------------------------------------ Inorganic chemicals Arsenic 0.05 Barium 1 Cadmium 0.010 Chromium 0.05 Fluoride 1.42 Lead 0.05 Mercury 0.002 Nitrate (as N) 10 Selenium 0.01 Silver 0.05 ----------------------------------------------------------------------------------------------------------------------

Table 5. Environmental Protection Agency National Interim Primary Drinking water regulation (1975); mg/L unless indicated ------------------------------------------------------------------------------ Constituent Maximum contaminant level ------------------------------------------------------------------------------ Organic chemicals Chlorinated hydrocarbons Endrin 0.0002 Lindane 0.004 Methoxyclor 0.1 Toxaphene 0.005 Chlorophenoxys 2,4-D 0.1 2,4,5-TP Silvex 0.01 ---------------------------------------------------------------------------------------------------------------------

Table 5. Environmental Protection Agency National Interim Primary Drinking water regulation (1975); mg/L unless indicated ------------------------------------------------------------------------------ Constituent Maximum contaminant level ------------------------------------------------------------------------------ Physical parameters Turbidity (TU) 1 Radioactivity Gross alpha (pCi/L) 15 Radium 226 and 228 (pCi/L) 5 Tritium (pCi/L) 20,000 Strintium 90 (pci/L) 8 Bacteriological factors Coliform bacteria (per 100 ml) 1 --------------------------------------------------------------------------------------------------------------------

Microbiological examination of water 1. Total bacterial count Water of good quality should give a low count <100/ml

a. Standard plate count

b. Membrane-filter technique

2.Enumeration of Coliforms and E. coli a. Colony count 1 ml 1 ml 10g sample 90 ml 9 ml 9ml Agar plates (VRBA) Dilution : 1:10 1:100 1:1000 Count the dark red colonies. Pick some colonies and inoculate LB and BGLB tubes. Incubate LB tubes at 35oC and BGLB tubes at 44-45oC. Growth and gas production in LB and BGLB tubes confirm the presence of coliforms and E. coli respectively.

b.Multiple tube technique 1ml 1ml 1ml 1ml 9ml 9ml 9ml 9ml 1:10 1:100 1:1000 1:10000 Sample being tested 1ml 1ml 1ml 1ml Observe for growth

Examples of Determining MPN Estimates: Five tube series (1-g sample aliquot per tube) _________________________________________________________________________________ Sample volume (g) -------------------------------------------------- Reported MPN Example 1:10 1:100 1:1000 1:10000 positive values estimate/g ------------------------------------------------------------------------------------------------------------------------ a 5/5a5/5 2/5 0/5 5-2-0 490 b 5/5 2/5 0/5 0/5 5-2-0 49 c 5/5 5/5 3/5 2/5 5-3-2 1400 d 5/5 5/5 5/5 5/5 5-5-5 >16,000 __________________________________________________________________________________ aNumerator No. of positive tubes ------------- = -------------------------- Denominiator No. of tubes inoculated To obtain the MPN per gram: [(MPN/g from Table/100)] x dilution factor of the middle tube = MPN/g

Fecal coliform group and E. coli determination 1. Subculture all positive tubes showing gas to EC broth. 2. Incubate for 24 h at 44.5- 45.5oC. 3. Calculate MPN fecal coliforms/g or ml 4. Subculture all EC tubes by streaking on EMB plates. 5. Incubate for 24 h at 35oC.

6. Examine plates for typical nucleated, dark-centered colonies with or without sheen. 7. Pick typical colonies and transfer to PCA slant. 8. Gram stain , subject to IMViC tests and inoculate the cultures to LST tubes. 9. Compute MPN of E. coli per g or ml, considering gram-negative, non-sporeforming rods, producing gas in lactose and producing ++-- or -+-- IMViC patterns as E. coli.

Water Sanitation