potable water

what is Leptospirosis

bacteria in urine (rats urban legend)

bottled vs tap

bottle more likely to develop bacteria faster and more abundant once opened in comparison to tap

how to disinfect water

chlorine (most common), Ozone, UV light

problem with chlorine and ozone disinfection

chlorine: chlorinated organics Ozone: chlorinated organics, no residual

Examples of fecal oral route disease

cholera, typhoid fever, hepatitis A, salmonellosis, bacterial dysentery (shigellosis), amoebic dysentery (amoebiasis)

how can people ingest a waterborne disease

drink, food preparation, and fecal-oral route

3 routes of infection for waterborne diseases

ingestion, contact, and inhalation

example of inhalation of contaminated waterborne disease

legionnaires disease

what contaminants to MCLs restrict

microorganisms, disinfectants, disinfection byproducts, inorganic chemicals, organic chemicals, radionuclides

are home filters effective?

pesticides and taste/odor- good solvents- some lead- moderate microbes- no

cost of water $1

pint bottle or gallon bottle or 200 gallons of tap

what are primary MCLs and Secondary based on

primary based on health and secondary based on aesthetic and economic

schematic process of general water treatment procedure

raw water, screen, rapid mix, flocculation (slow mix), settling, sand filter, activated carbon, add chlorine, to storage

how is fecal to oral possible

sewage contaminates water supply and travels to water of next town (down stream)

how do home filters work?

small filter and activated carbon adsorption

what is Schistosomiasis

topical disease caused by flatworm in standing water. (contact)

Sand Filtration

trenches with sand filtration deem resourceful to filter cleaner water supply

describe southwark and vauxhall company vs lambeth company

two competing private water suppliers. the untreated water from Thames was different for each co. SVC got polluted water from London and LC got water from upstream in london (clean)... SVC much higher cholera death rate

Ways of water contact and potential diseases

washing, swimming, wading, splashing schistosomiasis, swimmers itch, leptospirosis, primary amebic meningocephalitis

what is potable water

water suitable for drinking

what is dermatitis

"swimmer's itch" bird poop infects water... eggs to parasite inhabits host (snail) to human exposure

Chain of events for waterborne disease

1. sick people excrete large # pathogens 2. poor sanitation puts pathogens in water 3. poor water treatment doesn't remove pathogens 4. bad water=sick people

Safe Drinking Water Act

1974; amended 1986. created public water systems (15 service connections for greater than or at least 60 days a yr). National Interim Primary Drinking Water Standards. Max contaminant level and MCL goals. establish secondary MCLs

describe broad street pump incident

London, 1854; cholera; john snow, red and black dots to mark pumps and deaths, public health measure taken to remove pump handle