Transcript document
Unit 9 – Public Health
Environmental Issues in Public
Health: Part II
Chapter 22 – Solid and Hazardous Wastes: What To
Do With the Garbage?
Before 1970s
Open dumps
Outlawed by Resource Conservation and Recovery Act
(RCRA), 1976
Burned in incinerators or in the open
Outlawed by Clean Air Act, 1970
Poured into rivers, lakes, or oceans
Outlawed by Clean Water Act (1972) and Marine
Protection, Research, and Sanctuaries Act (1972)
Sanitary Landfills
Site should be dry, impervious clay soil
Lined with plastic
Drains for liquids
Vents to control explosive gases
Tipping fee
Cost of disposing of one ton of municipal waste
Highest cost is in northeast
New York City – Fresh Kills, Staten Island
Alternatives to Landfills
Three R’s: Reduce, Reuse, Recycle
Reduce: buy only what’s needed; avoid excessive
packaging
Reuse: Use reusable items rather than disposable
Recycle
Encouraged by deposits on bottles and cans
Yard sales
Composting
Waste to energy incineration
Special incinerators -- still concern about pollution
Hazardous Wastes
Love Canal, New York – 1978
Times Beach, Missouri – 1972-1976
Resource Conservation and Recovery Act, (RCRA),
1976, 1984
All hazardous wastes accounted for “from cradle to
grave”
Wastes from petroleum refining, pesticide
manufacturing, some pharmaceuticals
Ignitable, corrosive, reactive, toxic wastes
Superfund
Comprehensive Environmental Response,
Compensation, and Liability Act – 1980
Emergency cleanup of old waste sites, paid for by a tax
on industry
Mired in controversy; much effort focused on
determining who is liable
Tax not reauthorized in 1995
NIMBY
Not In My Back Yard
Unit 9 – Public Health
Environmental Issues in Public
Health: Part II
Chapter 23 – Safe Foods and Drugs: An Ongoing
Regulatory Battle
Causes of Food-Borne Illness
Bacteria
Salmonella -- eggs, poultry, meat
E. coli O157:H7 – ground beef, alfalfa sprouts,
unpasteurized apple juice, raw milk, lettuce
Viruses
Hepatitis A – green onions from Mexico, shellfish
Norwalk virus -- shellfish
Parasites
Cyclospora – raspberries from Guatemala
Parasites in sushi, sashimi, ceviche
Government Food Safety Activities
Responsibility is divided among many agencies
Department of Agriculture (USDA) – meat,
poultry, processed eggs
Food and Drug Administration (FDA) – all other
foods
States regulate shellfish
State and local governments regulate stores,
restaurants, institutions (schools, nursing homes)
Irrationality of System
USDA has bigger budget, more authority
Regulates 20% of food
Detailed laws on regulation of meat
FDA has smaller budget, less authority
Regulates 80% of food
Inspects only 1% proportion of imported food
55% of seafood is imported
12% of vegetables
30% of fruit
Safety Measures
Hazard Analysis Critical Control Point (HACCP)
Focuses on procedures; reduces need for inspections
Irradiation – kills bacteria, parasites, pests
CDC surveillance for food-borne disease
FoodNet
Pulsenet – DNA fingerprinting of bacteria
Additives and Contaminants
FDA sets tolerance levels for pesticide residues
Hormones
Estrogen banned in chickens
Bovine growth hormone allowed for cows (does not get
into milk)
Antibiotics – causes antibiotic resistance
Organic foods – USDA set standards in 2004
Additives
To prevent deficiency diseases
Preservatives or to improve color, flavor or texture
Must be approved by FDA, or GRAS
Drugs
FDA must approve after studies by pharmaceutical
company
New Drug Application
Three phases of trial
I. Small number of subjects, measure absorption,
distribution, metabolism, excretion; look for side effects
and toxicities
II. Signs of effectiveness
III. Clinical trial
Post-marketing surveillance
Food and Drug Labeling and
Advertising
FDA regulates labeling of foods with information on
specified nutrients, recommended daily intakes
FDA regulates labeling of drugs
Labeling of over-the-counter drugs is by Federal Trade
Commission
Dietary Supplements
Dietary Supplement Health and Education Act – 1994
Forbids FDA from regulating herbs and food
supplements
Can remove substance from market only if proven
harmful
Ephedra removed only after many deaths
Politics of the FDA
FDA subject to intense political pressures
Complaints it is too slow in approving drugs
Drug companies pay a fee to speed up review process
Now complaints that the FDA is too cozy with industry
Politics of the FDA, ctd.
Too many drugs found to be unsafe only after
approved for marketing
Fen-phen
Vioxx
Antidepressants for children
Problems with the way clinical trials are reported
Calls for a database of all clinical trials, to be
registered at the beginning of the trial, with all
results to be reported
Unit 9 – Public Health
Environmental Issues in Public
Health: Part II
Chapter 24 – Population: The Ultimate
Environmental Health Issue
Population Biology
Patterns of population growth: S curve and J curve
Carrying capacity – number of organisms that can be
supported without degrading environment
Thomas Malthus predicted in about 1800 that
population growth would outgrow food supply
Paul Ehrlich – The Population Bomb, 1968
Population growth has slowed, but many negative
effects of overpopulation are occurring
Public Health and Population Growth
Public health has contributed to population growth by
reducing death rates, especially among children, in
developing countries
Birth rates tend to fall as a result of falling death rates –
demographic transition
Excess population settles in cities – homelessness,
shantytowns – poor sanitation
HIV/AIDS shortening life expectancies in Africa
Depletion of Global Resources
Fresh water
Drinking, cooking, washing
Agriculture
Unevenly distributed
Fuel
Deforestation – leads to degradation of land
Arable land
Amount of land under cultivation is declining
Food from the sea
Decline of harvests of fish and shellfish
Climate Change
Greenhouse effect from burning fossil fuels
Rise of 1 degree during 20th century
Predict 3 to 8 degree rise during 21st century
U.S. has 5% of world’s population, contributes 21% of
greenhouse gases
Kyoto Protocol – Bush administration has rejected
Prospects for Population Control
U.N. conference in Cairo, 1994
Opposition to contraception by Catholics and Muslims
Rich and poor countries blame each other
20 year Programme of Action
Education for women
Empowering women to choose fewer children
Population stabilization comes with modernization and
economic viability