Ordering of Perceived RiskOrdering of Perceived RiskActivity League of
Women VotersCollege
StudentsExperts
Nuclear Power 1 1 20
Motor Vehicles 2 5 1
Handguns 3 2 4
Smoking 4 3 2
Motorcycles 5 6 6
Alcoholic Bev. 6 7 3
General Aviation 7 15 12
Police Work 8 8 17
Pesticides 9 4 8
Surgery 10 11 5
Firefighting 11 10 18
X-rays 22 17 7
Risk, Toxicology, and Human HealthRisk, Toxicology, and Human Health
G. Tyler Miller’sLiving in the Environment
13th Edition
Chapter 11
G. Tyler Miller’sLiving in the Environment
13th Edition
Chapter 11
Human HealthHuman Health
• Health is a state of complete physical, mental, social and spiritual well-being and not merely the absence of disease or infirmity
or• The ability to lead a socially and
economically productive life
Holistic Concept of HealthHolistic Concept of Health
• This concept recognizes the strength of social, economic, political and environmental influences on health
• Determinants– Heredity– Health and family welfare services – Environment– Life-style– Socio-economic conditions
Risk and ProbabilityRisk and Probability
Risk possibility of suffering harm from a hazard that can cause injury, disease, economic loss, or environmental damage.
Risk possibility of suffering harm from a hazard that can cause injury, disease, economic loss, or environmental damage.
Probability mathematical statement about how likely it is that some event or effect will occur.
Risk = pExposure x pHarm
Probability mathematical statement about how likely it is that some event or effect will occur.
Risk = pExposure x pHarm
Risk Assessment and ManagementRisk Assessment and Management
Risk AnalysisRisk Analysis
1)1) Identifying hazardsIdentifying hazards• Risk assessmentRisk assessment
2)2) Ranking risksRanking risks• Comparative risk analysisComparative risk analysis
3)3) Determining optionsDetermining options• Risk managementRisk management
4)4) Informing decision makersInforming decision makers• Risk communicaitonRisk communicaiton
How well do we perceive risks?How well do we perceive risks?How well do we perceive risks?How well do we perceive risks?
Most of us do Most of us do poorlypoorly at assessing the at assessing the relative risks from the hazards that relative risks from the hazards that surround us.surround us.
What do you think are the highest risk hazards in the U.S.?
What do you think are the highest risk hazards in the U.S.?
Fig. 16.1, p. 396
DeathsCause of Death
Tobacco use 431,000
Alcohol use
Accidents
Pneumonia andInfluenza
Suicides
Homicides
Hard drug use
AIDS
150,000
95,600 (42,000 auto)
84,400
30,500
19,000
15,000
14,000
Fig. 16.15, p. 414
Hazard Shortens average life spanin the United States by
7-10 yearsPoverty
Born male
Smoking
Overweight (35%)
Unmarried
Overweight (15%)
Spouse smoking
Driving
Air pollution
Alcohol
Drug abuse
AIDS
Drowning
Pesticides
Fire
Natural radiation
Medical X rays
Oral contraceptives
Toxic waste
Flying
Hurricanes, tornadoes
Living lifetime nearnuclear plant
7.5 years
6 years
6 years
5 years
2 years
1 year
7 months
5 months
5 months
4 months
3 months
1 month
1 month
1 month
8 days
5 days
5 days
4 days
1 day
1 day
10 hours
Yet some of these people are terrified of dying from…
Yet some of these people are terrified of dying from…
• Commercial plane crash– 1 in 4.6 million
• Train crash – 1 in 20 million
• Snakebite – 1 in 36 million
• Shark attack – 1 in 300 million
ToxicologyToxicologyToxicologyToxicology
Toxicity measures how harmful a Toxicity measures how harmful a substance issubstance is. Toxicity depends on . .. Toxicity depends on . .
• DoseDose
– the amountthe amount of a potentially of a potentially harmful harmful substancesubstance a person has ingested, inhaled, a person has ingested, inhaled, or absorbed.or absorbed.
• ResponseResponse
– the type or amount of the type or amount of damagedamage
ToxicityToxicityToxicityToxicity
DoseDose - - the amount of a potentially harmful the amount of a potentially harmful substance a person has ingested, inhaled, or substance a person has ingested, inhaled, or absorbed.absorbed.
• SolubilitySolubility• PersistencePersistence• BioaccumulationBioaccumulation• BiomagnificationBiomagnification• Chemical interactionsChemical interactions
– Antagonistic: reducesAntagonistic: reduces– Synergistic: multipliesSynergistic: multiplies
Bioaccumulation and BiomagnificationBioaccumulation and BiomagnificationBioaccumulation and BiomagnificationBioaccumulation and Biomagnification
Fig. 11-4p. 231
ToxicityToxicityToxicity LD50 Lethal Dose Examples
Super < 0.01 less than 1 drop dioxin, botulismmushrooms
Extreme <5 less than 7 drops heroin, nicotine
Very 5-50 7 drops to 1 tsp. morphine, codeine
Toxic 50-500 1 tsp. DDT, H2SO4, Caffeine
Moderate 500-5K 1 oz.-1 pt. aspirin, wood alcohol
Slightly 5K-15K 1 pt. ethyl alcohol, soaps
Non-Toxic >15K >1qt. water, table sugar
(LD50 measured in mg/kg of body weight)
ToxicityToxicityToxicityToxicity
Response Response - - the type or amount of damagethe type or amount of damage
• Acute effect: immediate or rapidAcute effect: immediate or rapid
• Chronic effect: permanent or long Chronic effect: permanent or long lastinglasting
Genetic Variation in Individual Responses to Toxins
Genetic Variation in Individual Responses to Toxins
““The dose makes the poison.The dose makes the poison.””Paracelsus, 1540Paracelsus, 1540
““The dose makes the poison.The dose makes the poison.””Paracelsus, 1540Paracelsus, 1540
Anything can be harmful if ingested in Anything can be harmful if ingested in a large enough quantity.a large enough quantity.
PoisonsPoisons
• a chemical that has an a chemical that has an LDLD5050 of 50 mg or less per of 50 mg or less per kg of body weightkg of body weight
• LDLD5050
– The The medianmedian lethal dose lethal dose• The amount that The amount that kills kills
exactly 50%exactly 50% of the of the animals in a test animals in a test population, within a 14 population, within a 14 day periodday period
• Determined by Determined by controlled experimentscontrolled experiments
Laboratory InvestigationsLaboratory Investigations
• Animal Studies– Populations of lab animals usually rodents– Measured doses under controlled conditions– Takes two to five years– Costs $200,000 to $2,000,000 per substance
• Newer methods
Laboratory InvestigationsLaboratory Investigations
• Newer methods– Bacteria– Cell and tissue culture
• Appropriate tissue
• Stem cells
– Chicken egg membrane
Laboratory InvestigationsLaboratory Investigations
• Validity Challenged– Human physiology is different– Different species react different to same toxins
• Mice die with aspirin
– Species can be selected depending on physiological area
• Pigs circulatory very similar to humans
Major Types of HazardsMajor Types of Hazards
Chemical hazardsChemical hazards
Physical hazardsPhysical hazards
Fig. 11-1 p. 228Fig. 11-1 p. 228
Biological hazardsBiological hazards
Cultural hazardsCultural hazards
Chemical HazardsChemical Hazards
• Toxic chemicalsToxic chemicals– substances that are fatalsubstances that are fatal
• Hazardous chemicalsHazardous chemicals– cause harmcause harm
• Flammable or explosiveFlammable or explosive• Irritating or damaging to skin or lungsIrritating or damaging to skin or lungs• Interfering or preventing oxygen uptakeInterfering or preventing oxygen uptake• Inducing allergic reactionsInducing allergic reactions
Chemical HazardsChemical Hazards
• MutagensMutagens– Cause random changes in DNACause random changes in DNA
– Passed on to future generationsPassed on to future generations
• TeratogensTeratogens– cause birth defectscause birth defects
– alcohol, PCBs, thalidomide, steroid alcohol, PCBs, thalidomide, steroid hormones, heavy metalshormones, heavy metals
Chemical HazardsChemical Hazards
• CarcinogensCarcinogens– promote uncontrollable cell growth promote uncontrollable cell growth
(malignant or cancerous tumors)(malignant or cancerous tumors)– metastasismetastasis
• cells break off from tumors and travel in body cells break off from tumors and travel in body fluidsfluids
• Immune, Nervous, and Endocrine System Immune, Nervous, and Endocrine System disruptorsdisruptors– Viruses (HIV), Ionizing radiation, Diet, Viruses (HIV), Ionizing radiation, Diet,
Neurotoxins, Hormonally Active AgentsNeurotoxins, Hormonally Active Agents
Biological Hazards: DiseasesBiological Hazards: Diseases
• Non-transmissible diseaseNon-transmissible disease– not caused by a living organismnot caused by a living organism– is not spread from one person to is not spread from one person to
anotheranother
• Transmissible diseaseTransmissible disease– caused by living organismscaused by living organisms
• Bacteria, virus, protozoaBacteria, virus, protozoa
– is spread from one person to anotheris spread from one person to another
Biological Hazards: DiseasesBiological Hazards: Diseases
• PathogensPathogens – infectious agents – infectious agents• VectorsVectors – organisms that spread pathogens – organisms that spread pathogens
– InsectsInsects
WorldWorld’’s Seven Deadliest Diseasess Seven Deadliest Diseases– acute respiratory infectionacute respiratory infection– acquired immune deficiency syndrome (AIDS)acquired immune deficiency syndrome (AIDS)– diarrheal diseasesdiarrheal diseases– tuberculosistuberculosis– malariamalaria– hepatitis Bhepatitis B– measlesmeasles
Biological Hazards: DiseasesBiological Hazards: Diseases
• Common Viral DiseasesCommon Viral Diseases1)1) influenza or fluinfluenza or flu
2)2) EbolaEbola
3)3) West Nile VirusWest Nile Virus
4)4) rabiesrabies
5)5) AIDSAIDS
• TreatmentTreatment– Immunization with vaccinesImmunization with vaccines
Anopheles mosquito (vector)
in aquatic breeding area
1. Femalemosquito bitesinfected human,ingesting bloodthat containsPlasmodiumgametocytes
4. Parasite invadesblood cells, causingmalaria and makinginfected persona new reservoir
3. Mosquito injects Plasmodiumsporozoites into human host
2. Plasmodiumdevelops inmosquito
eggs
larvapupa
adult
Malaria -
A Protozoal Disease
Waterborne BacteriaWaterborne Bacteria
Escherichia coli Vibrio sp.Barbara E. Moore, Ph.D., Department of Biology, University of Texas at San Antonio
• Disease symptoms usually are explosive emissions from either end of the digestive tract
Waterborne ProtozoansWaterborne Protozoans
Giardia sp.**P. Darben
Barbara E. Moore, Ph.D., Department of Biology, University of Texas at San Antonio
• Disease symptoms are usually Disease symptoms are usually explosive emissions from either explosive emissions from either end of the digestive tractend of the digestive tract
Waterborne Human VirusesWaterborne Human Viruses
Hepatitis A virus Hepatitis E virus
Norwalk virus* Rotavirus**F. Williams
Barbara E. Moore, Ph.D., Department of Biology, University of Texas at San Antonio
Case Study on Eradicating DracunculiasisCase Study on Eradicating Dracunculiasis
Water and Sanitation – Critical Elements in Development - Mike Lee CSU @ HaywardWater and Sanitation – Critical Elements in Development - Mike Lee CSU @ Hayward
Guinea Worm DiseaseGuinea Worm Disease• People have suffered from Guinea Worms for
centuries – the “fiery serpent” was mentioned in the bible
• People are infected by drinking water that contain the larvae in a tiny freshwater crustacean called Cyclops
• A year later, larvae mature into 3 feet worms that emerge through skin blisters
• This is such a painful process that men and women can’t work, children can’t attend school
Water and Sanitation – Critical Elements in Development - Mike Lee CSU @ Hayward
http://www.pmeh.uiowa.edu/fuortes/63111/GUINEA/
The Guinea Worm grows down the leg and its sex organs appear at the ankle or on the foot usually, bursting when it senses water, releasing ova.
The Guinea Worm grows down the leg and its sex organs appear at the ankle or on the foot usually, bursting when it senses water, releasing ova.
Water and Sanitation – Critical Elements in Development - Mike Lee CSU @ Hayward
• No vaccine for Guinea worm is available.
• People do not seem to build up any resistance and the disease can be reinfected over and over.
• No research is being conducted for any vaccine or cure.
• Worms are removed slowly each day by winding around a stick.
http://www.pmeh.uiowa.edu/fuortes/63111/GUINEA/Water and Sanitation – Critical Elements in Development - Mike Lee CSU @ Hayward
Spread of DiseasesSpread of Diseases
• Increases international travel• Migration to urban areas• Migration to uninhabited areas and deforestation• Hunger and malnutrition• Increased rice cultivation• Global warming• Hurricanes and high winds• Accidental introduction of insect vectors• Flooding
Reducing Spread of DiseasesReducing Spread of Diseases
• Increase research on tropical diseases and vaccines
• Reduce poverty and malnutrition• Improve drinking water• Reduce unnecessary use of antibiotics• Educate people on taking antibiotics• Reduce antibiotic use in livestock• Careful hand washing by medical staff• Slow global warming• Increase preventative health care
EpidemiologyEpidemiology
• Study of the distribution and causes of disease in populations– how many people or animals have a disease
– the outcome of the disease (recovery, death, disability, etc.)
– the factors that influence the distribution and outcome of the disease
Physical HazardsPhysical Hazards
• Ionizing radiation, airborne particles, equipment design, fire, earthquake, volcanic eruptions, flood, hurricane, tornado
• Example: Radon– Source:
• Arises naturally from decomposition of uranium in the Earth
• Occurs at dangerous levels in some buildings and homes “sick buildings”
– Can cause lung cancer
Cultural HazardsCultural Hazards
• Sociological– Results from living in a society where
one experiences noise, lack of privacy, and overcrowding• Population growth
– Beyond carrying capacity when environmental resources can support no further growth
Cultural HazardsCultural Hazards
• Psychological – Environmental factors that produce psychological
changes expressed in stress, depression and hysteria
