APEs Chapter 16: Environmental Hazards and Human Health

Four greatest risks in terms of shortened life spans

-living in poverty -smoking -obesity -being born male

The effects of a chemical rely on

1. Dose 2. Age 3. Genetic makeup 4. Synergy 5. Solubility 6. Persistence

Five factors people see technology or a product as being more or less risky than experts judge it to be

1. Fear 2. Degree of control 3. Whether a risk is catastrophic or chronic 4. Optimism bias 5. Instant gratification

Why are children more susceptible to toxins than adults

1. They generally breathe, drink, and eat more per unit of body weight than do adults 2. They are exposed to toxins in dust and soil when they put their finger, toys, and other objects in their mouth 3. Children have a less developed immune systems and Boyd detoxification processes than adults

Threshold level model

A certain level exposure to the chemical must be reached before any detectable harmful effects occur, presumable because the body can repair the damage caused by low dosages of some substances

Infectious disease

A disease caused by a pathogen such as bacterium, virus, or parasite invading the body and multiplying in its cells and tissues

Why has the percentage of all deaths world-wide resulting from infectious disease dropped

A growing number of children have been immunized against the major infectious diseases

Toxicity

A measure of the ability of a substance to cause injury, illness, or death to a living organisms

Toxic chemical

An elements or compound that can cause temporary or permanent harm or death to humans

Acute effect

An immediate or rapid harmful reaction ranging from dizziness to death

Viruses are not affected by ________

Antibiotics

Three agents of infectious disease

Bacteria, virus, parasite

five major types of hazards that threaten human health

Biological, chemical, natural, cultural, lifestyle choices

Three major types of potentially toxic agents

Carcinogens, teratogens, mutagens

Nontransmittable disease

Caused by something other than a living organism and does not spread from one person to another ; they involve cancers, asthma, and diabetes

Teratogens

Chemicals that harm or cause birth defects in a fetus or embryo (drinking alcohol while pregnant)

Carcinogen

Chemicals, some types of radiation., and certain viruses that can cause or promote cancer

___________ is the world most preventable and largest cause of suffering and premature death among adults

Cigarette smoking

What is the most widely used method for determining toxicity

Exposing a population of live laboratory animals to measured doses of a specific substance under controlled conditions

How does the immune system protect against disease

Forming antibodies

Risk analysis

Identifying hazards and evaluation their associated risk , ranking risks, and informing decision makers and the public about risks

Mutagens

Includes chemicals or forms of radiation that cause or increase the frequency of mutations (changes in the DNA molecules found in cells). Most mutation cause no harm, however some can lead to cancers

Why has Malaria increased since 1970

Malaria carrying mosquitos grew immune to pesticides

Pathogens

Microorganisms that can cause disease in order organisms

__________ harm the human nervous system

Neurotoxins

synergistic interaction (synergy)

Occurs when two or more compounds interact magnifying the effect of both compounds

Parasites

Organism that live on or insides other organisms and feed on them b

Viruses

Pathogens that work by invading a cell and taking over its genetic machinery to copy themselves in order to spread throughout the body ; they can cause diseases such as flu and AIDS

How does the precautionary principle apply to manufacturing and business

People argue that a company proposing a new chemical should should bear the burden of establishing its safety; however, this is incredibly expensive, and sometimes even impossible without real world application

Why is TB hard to control

People don't know they have it so they spread it to others You have to take medication for 6-9 months and many people stop

Bacteria

Single-called organisms that are found everywhere and that can multiply rapidly o their own; they can be both harmful and beneficial

Formula for system reliability

System reliability = technology reliability x human reliability

Median lethal dose

The dose of medication that kills 50% of the drug-tested population

Unconventional model

The harmful effects increase with dosage to a certain point and then begin decreasing

Response

The health damage resulting from exposure to a chemical

Risk

The probability of suffering harm from a hazard that can cause injury, disease, death, economic loss, or damage

Toxicology

The study of the harmful effects of these and other chemicals on humans and other organisms

What allows synthetic chemicals to attach to hormones and disrupt the endocrine system

They have similar shapes/receptors

Why are neurotoxins like methylmercury, DDT, and PCBs extremely dangerous

They persist in the environment and can be biologically magnified in food chains and food webs

dose-response curve

When scientists estimate the toxicity of a chemical by determining the effects of various doses of the chemical on test organisms and plotting the results on this type of graph

The precautionary principle states that:

When there is substantial preliminary evidence that an activity, technology, or chemical substance can harm humans, other organism, or the environment, decision makers should should take measure to prevent or reduce such harm, rather than waiting for more conclusion evidence scientific evidence.

Chronic effect

a permanent or long-lasting consequence of exposure to a single dose or to repeated lower doses of a harmful substance

Transmittable disease

an infectious disease that can be transmitted from one person to another, they can be spread through air, water, and food

nonthreshold dose-response model

any dosage of a toxic chemical causes harm that increases with the dosage

Risk Management

deciding whether or how to reduce a particular risk to a certain level and at what cost.

Dose

the amount of a harmful chemical that a person has ingested, inhaled, or absorbed through the skin at any one time

Risk assessment

the process of using statistical methods to estimate how much harm a particular hazard can cause to human health or to the environment.