Updates Online: Weblinks See the latest Weblinks for this chapter online or click highlighted articles below (weblinks subject to change) latest Weblinks latest Weblinks Section 5: Preventing Injuries, Saving Lives Section 5: Preventing Injuries, Saving LivesPreventing Injuries, Saving LivesPreventing Injuries, Saving Lives

Risk, Human Health, and Toxicology Chapter 14

The Big Killer Tobacco Tobacco Health threats Health threats Nicotine Nicotine Passive smoking Passive smoking Costs of smoking Costs of smoking Anti-smoking programs Anti-smoking programs Fig. 14-1, p. 327

Risk and Hazards Risk - is a measure of your likelihood of suffering harm from a hazard. Risk - is a measure of your likelihood of suffering harm from a hazard. Probabilities - a mathematical statement about how likely it is that harm will result form a hazard. Probabilities - a mathematical statement about how likely it is that harm will result form a hazard. Possibilities - saying that an event could happen. Possibilities - saying that an event could happen. Risk assessment - estimating how much harm a particular hazard can cause to human health. Risk assessment - estimating how much harm a particular hazard can cause to human health. Risk management - deciding whether to and how to reduce a risk and at what cost. Risk management - deciding whether to and how to reduce a risk and at what cost.

Hazard identification What is the hazard? Probability of risk How likely is the event? Consequences of risk What is the likely damage? Risk Assessment Risk Management Comparative risk analysis How does it compare with other risks? Risk reduction How much should it be reduced? Risk reduction strategy How will the risk be reduced? Financial commitment How much money should be spent? Risk Assessment and Risk Management Fig. 14-2, p. 328

Major Types of Hazards Cultural Cultural Biological Biological Chemical Chemical Physical Physical

Biological Hazards Nontransmissible diseases - not caused by living organisms and does not spread from person to person Nontransmissible diseases - not caused by living organisms and does not spread from person to person Transmissible (infectious) diseases - caused by living organisms and can spread. Transmissible (infectious) diseases - caused by living organisms and can spread. Pathogen - organism that produces disease. Carried by air, water, insects, body fluids, other vectors, and food. Pathogen - organism that produces disease. Carried by air, water, insects, body fluids, other vectors, and food. Germ resistance to antibiotics Germ resistance to antibiotics

Global Threats from Disease Tuberculosis Tuberculosis Viral diseases Viral diseases HIV and AIDS, Influenza, (HBV) hepatitis B virus HIV and AIDS, Influenza, (HBV) hepatitis B virus Malaria Malaria Reducing incidences of infectious diseases Fig 14-7 Reducing incidences of infectious diseases Fig 14-7 Bioterrorism Bioterrorism

Fig. 14-3, p. 329 Disease (type of agent) 3.2 million Pneumonia and flu (bacteria and viruses) HIV/AIDS (virus) Diarrheal diseases (bacteria and viruses) Tuberculosis (bacteria) Malaria (protozoa) Hepatitis B (virus) Measles (virus) Deaths per year 3.0 million 1.9 million 1.7 million 1 million 800,000 Seven Deadliest Infectious Diseases

Fig. 14-4, p MaleFemale Population (thousands) Age With AIDS Without AIDS Impact of AIDS on Age Structure of Botswana, Africa

Fig. 14-5, p. 331 Distribution of Malaria

Sporozoites penetrate liver and develop into merozoites Female mosquito bites infected human, ingesting blood that contains Plasmodium gametocytes Merozoites enter blood-stream and develop into gametocytes causing malaria and making infected person a new reservoir Female mosquito injects Plasmodium sporozoites into human host Plasmodium develops in mosquito Fig. 14-6, p. 332 Life Cycle of Malaria

Fig. 14-7, p. 333 Solutions Infectious Diseases Increase research on tropical diseases and vaccines Reduce poverty Decrease malnutrition Improve drinking water quality Reduce unnecessary use of antibiotics Educate people to take all of an antibiotic prescription Reduce antibiotic use to promote livestock growth Careful hand washing by all medical personnel Immunize children against major viral diseases Oral rehydration for diarrhea victims Global campain to reduce HIV/AIDS Solutions for Infectious Diseases

Agent Smallpox (virus) Hemorrhagic fever (viruses) Inhalation anthrax (bacterium) Botulism (bacterium) Pneumonic plague (bacterium) Tularemia (bacterium) Contagious Yes No Yes No Symptoms Fever, aches, headache, red spots on face and torso Vary but include fever, bleeding, shock, and coma Fever, chest pain, difficulty breathing, respiratory failure Blurred vision, progressive paralysis, death within 24 hours if not treated High fever, chills, headache, coughing blood, difficulty breathing, respiratory failure Fever, sore throat, weak- ness, respiratory stress, pneumonia Mortality (if untreated) 30% Varies 90–100% 60–100% 90–100% 30–60% Existence of vaccine Yes No Yes No Yes (in testing) Treatment Vaccination within 4 days after exposure, IV hydration Ebola has no cure, antiviral riboflavin and some antibiotics may help Early treatment with Cipro and other antibiotics Equine antitoxin given early. Intensive care, respirator Antibiotics Fig. 14-8, p. 334 Characteristics of Agents that Could be Used as Biological Weapons

Chemical Hazards Toxic and hazardous chemicals - Can cause temporary or permanent harm or death to living organisms. Toxic and hazardous chemicals - Can cause temporary or permanent harm or death to living organisms. Mutagens - cause or increase mutations, or changes, in DNA molecules. Mutagens - cause or increase mutations, or changes, in DNA molecules. Teratogens - cause harm or birth defects to a fetus or embryo. Teratogens - cause harm or birth defects to a fetus or embryo. Carcinogens - chemicals or radiation that cause or promote cancer. Carcinogens - chemicals or radiation that cause or promote cancer. Metastasis - malignant cells break off from tumors and travel to other parts of the body. Metastasis - malignant cells break off from tumors and travel to other parts of the body. Effects on immune, nervous, and endocrine systems Effects on immune, nervous, and endocrine systems Neurotoxins - PCB’s, methyl mercury, lead, some pesticides (parathion) Neurotoxins - PCB’s, methyl mercury, lead, some pesticides (parathion) Hormonally active agents (HAAs) Endocrine disruptors - PCBs, DDT, and certain herbicides Hormonally active agents (HAAs) Endocrine disruptors - PCBs, DDT, and certain herbicides

Toxicology Toxicity - a measure of how harmful a substance is in causing injury, illness, or death to al living organism. Toxicity - a measure of how harmful a substance is in causing injury, illness, or death to al living organism. Dose - the amount of a substance a person has ingested, inhaled, or absorbed through the skin. Dose - the amount of a substance a person has ingested, inhaled, or absorbed through the skin. Relevance of genetic makeup Relevance of genetic makeup Multiple chemical sensitivity (MCS) - individuals sensitive to a number of toxins. Multiple chemical sensitivity (MCS) - individuals sensitive to a number of toxins. Five factors affect the harm caused by a substance Five factors affect the harm caused by a substance Solubility Solubility Water-soluble toxins - often inorganic Water-soluble toxins - often inorganic Oil- or fat-soluble toxins - organic (DDT) Oil- or fat-soluble toxins - organic (DDT) Persistence - DDT Persistence - DDT Bioaccumulation Bioaccumulation Biomagnification - DDT, PCB Biomagnification - DDT, PCB Chemical Interactions Antagonistic interactions - reduce harmful effects Synergistic interactions - multiplies harmful effects Chemical Interactions Antagonistic interactions - reduce harmful effects Synergistic interactions - multiplies harmful effects

Toxicology Acute toxic effects - immediate of rapid reaction to an exposure Acute toxic effects - immediate of rapid reaction to an exposure Chronic toxic effects - permanent or long-lasting consequences Chronic toxic effects - permanent or long-lasting consequences “The dose is the poison” “The dose is the poison” Toxicity varies with individuals Toxicity varies with individuals How the human body disposes of chemical toxins Break it down, repair the damage, replace the cells How the human body disposes of chemical toxins Break it down, repair the damage, replace the cells Effects of trace levels of toxic chemicals Effects of trace levels of toxic chemicals

Estimating Toxicity LD50 LD50 Using case reports Using case reports Epidemiological studies (experimental and control groups) Epidemiological studies (experimental and control groups) Limits of epidemiological studies Limits of epidemiological studies Laboratory studies Laboratory studies Controversies with testing with animals Controversies with testing with animals Nonthreshold and threshold dose-response models Nonthreshold and threshold dose-response models

Fig. 14-9, p. 337 LD Dose (hypothetical units) Percentage of population killed by a given dose Dose-Response Curve

Table 14-1, p. 337 Toxicity Ratings

Fig , p. 338 Effect Dose Nonlinear dose-response Linear dose-response No threshold Effect Threshold level Dose Threshold and Nonthreshold Dose-Response Curves

Protection Against Harmful Chemicals Protecting children from toxic chemicals Protecting children from toxic chemicals Why do we know so little about the harmful effects of chemicals? Why do we know so little about the harmful effects of chemicals? Lack of regulations Lack of regulations Pollution prevention Pollution prevention Precautionary principle Precautionary principle “Innocent until proven guilty” approach “Innocent until proven guilty” approach Persistent organic pollutants (POPs) (“dirty dozen”) Persistent organic pollutants (POPs) (“dirty dozen”)

Risk Analysis Risk analysis (risk assessment) - Identifying hazards and evaluating their associated risks. Risk analysis (risk assessment) - Identifying hazards and evaluating their associated risks. Comparative risk analysis - ranking risks Comparative risk analysis - ranking risks Risk management - determining the options and making decisions about reducing or eliminating risks. Risk management - determining the options and making decisions about reducing or eliminating risks. Risk communication - informing decisions makers and the public about risks. Risk communication - informing decisions makers and the public about risks. Poverty: the greatest risk Poverty: the greatest risk Risks from lifestyle Risks from lifestyle

Fig , p. 340 Comparative Risk Analysis Most Serious Ecological And Health Problems High-Risk Health Problems Indoor air pollution Outdoor air pollution Worker exposure to industrial or farm chemicals Pollutants in drinking water Pesticide residues on food Toxic chemicals in consumer products High-Risk Ecological Problems Global climate change Stratospheric ozone depletion Wildlife habitat alteration and destruction Species extinction and loss of biodiversity Medium-Risk Ecological Problems Add deposition Pesticides Airborne toxic chemicals Toxic chemicals, nutrients, and sediment in surface waters Low-Risk Ecological Problems Oil spills Groundwater pollution Radioactive isotopes Acid runoff to surface waters Thermal pollution Comparative Risk Analysis

Estimating Risks from Technologies System reliability (%) = Technology reliability x Human reliability Difficulties in estimating reliability Difficulties in estimating reliability “To err is human” “To err is human” Automatic control systems Automatic control systems

Fig , p. 341 Cause of DeathAnnual Deaths 11 million (75) Poverty/malnutrition/ disease cycle Tobacco Pneumonia/flu Air pollution HIV/AIDS Malaria Diarrhea Auto accidents Work related injury Measles 5 million (34) 3.2 million (22) 3 million (21) 1.9 million (13) 1.7 million (12) 1.2 million (8) 1.1 million (8) 1 million (7) 800,000 (5) Hepatitis B Number of Deaths Per Year Globally Tuberculosis

Fig , p years Poverty 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 near nuclear plant 6-10 years 5 years 2 years 1 year 7 months 5 months 4 months 3 months 2 months 1 month 8 days 5 days 4 days 1 day 10 hours Flu Air Pollution 6 years 5 months 1 month 7.5 years HAZARD SHORTENS AVERAGE LIFE SPAN IN THE UNITED STATES BY Comparison of Risks

Perceiving Risks Distorted perceptions of risks Distorted perceptions of risks Degree of control Degree of control Fear of the unknown and distrust of the new Fear of the unknown and distrust of the new Whether we voluntarily take the risk Whether we voluntarily take the risk Whether the risk is catastrophic Whether the risk is catastrophic Unfair distribution of risks Unfair distribution of risks