Chapter 8: Environmental Health and Toxicology
The Black Death, the 1918 influenza, and the H1N1 flu virus were all ______, as they caused widespread and worldwide infections.
pandemics
A metal such as lead that is stable, resistant to degradation, and can impair children's health long after exposure and far from where it might have first been used is of concern because of its _______.
persistence
Another term for toxin is ______.
poison
Risk is defined as the ______.
possibility of suffering harm or loss resulting from a given action
Outbreaks of health problems that have a psychological rather than a physical basis are referred to as ______.
psychogenic conditions
The possibility of suffering harm or loss resulting from a given action is referred to as ______.
risk
Factor related to the exposure
Dose and frequency of contact with the chemical
True or false: All species have approximately the same reaction to a specific compound.
False
True or false: Ecological diseases are infectious diseases that strictly affect wildlife or cause damage to habitats.
False
Nearly all substances are toxic depending on the amount, delivery rate, and method. This idea is summarized in the statement "the ____ makes the poison."
dose
Of the many factors that determine whether a particular chemical will prove to be dangerous, which of the following are based on the nature of the chemical agent itself?
The chemical agent is not biodegradable and thus is persistent in the environment. The chemical agent is water-soluble.
In assessing the danger of toxic substances, which of these statements are true?
The dose makes the poison. Our increasing ability to detect traces of a substance sometimes means that though we can detect it, the level may be too low to cause harm.
Which of the following statements are reasonable conclusions that can be drawn from a recent headline that announced the discovery of 23 pesticides in 16 food samples?
The mere presence of a toxin is insignificant without considering how much is there, where it is located, how accessible it is, and who is exposed. Pesticide residues are not necessarily harmful, for a substance produces a harmful effect only if it reaches within the body in a high enough dose.
Car accidents and firearm assaults
These have risks between 1 in 103 to 1 in 285.
Dog bites and bee, wasp, or hornet stings
These have risks between 1 in 46,562 to 1 in 115,111.
Heart disease and cancer
These have risks of 1 in 6-7.
Which of the following applies to ecological diseases?
They affect wildlife populations, such as bats and frogs.
What are the qualities of PFCs that make them so useful?
They are slippery, heat-resistant, and durable.
Which of the statements below accurately captures the relationship between toxicity and potency?
Though categorizing toxins based on potency is useful, it is complicated by differences in individual and species reactions to particular chemicals.
True or false: According to the World Health Organization (WHO) definition of health, we are all ill to some extent.
True
True or false: Our bodies often reduce the effects of toxic substances by eliminating them through our breath, sweat, and urine.
True
True or false: The World Health Organization (WHO) estimates that though 90 percent of all disease burden occurs in developing nations only about 10 percent of health care dollars are spent there.
True
True or false: Wind turbine syndrome is considered a psychogenic condition because people who are opposed to wind turbines often claim that noise and shadow flicker caused by moving turbines make them sick even though there is no medical evidence for cause and effect.
True
Which of the following statements accurately reflect how allergens affect us?
Allergens act as antigens and stimulate the production of specific antibodies. Allergens activate the immune system.
Why is diet a consideration in health?
- Diet-related obesity can lead to illnesses such as diabetes and cardiovascular disease. - Vegetables, whole grains, and other healthy foods can boost our ability to tolerate toxins.
Endocrine disrupters like BHA in facial moisturizers
Absorption (dermal)
Developing radiation sickness after exposure to radiation
Acute effect
Exposure to radiation during an x-ray for a broken foot
Acute exposure
Which of the following is an example of a synergistic effect?
Asbestos exposure and smoking each increase lung cancer rates 20-fold. Asbestos workers who smoke, however, have a 400-fold increase in cancer rates.
POPs, or , _____ are dangerous because they don't degrade quickly and cells readily take them up.
Blank 1: persistent Blank 2: organic Blank 3: pollutants
Exposure to background radiation, like from radon gas
Chronic Exposure
Developing lung cancer after exposure to radiation
Chronic effect
Which of the following statements about chronic and acute exposure and effects are correct?
Chronic exposure involves continuous or repeated contact with a toxic substance over a long period of time (months or years). Acute exposure involves a single contact with a toxic chemical. It may last a few seconds or a few hours.
Which of these statements correctly describes trends in child mortality?
Clean water and improved sanitation support the declining trends. It remains higher in sub-Saharan Africa than elsewhere. It is declining globally.
Factor related to the toxic agent
Composition and reactivity of the chemical
Which of the following statements about the potency (strength) of toxic substances is true?
For some toxic substances, a millionth of a gram (an amount invisible to the naked eye) can be lethal.
Factor related to the organism
Immunological status at the time of exposure to the chemical
Pesticide residue on food
Ingestion (gastrointestinal tract)
Toluene and formaldehyde from cigarette smoke
Inhalation (respiratory tract)
Certain pharmaceuticals, vaccines, and drugs
Injection (intramuscular)
Excreting water-soluble salts and other substances
Kidneys
Detoxification
Liver
Exhaling excess carbon dioxide
Lungs
What does the saying "the dose makes the poison" mean?
Most substances are toxic at some level of exposure depending on the substance and the nature of the exposure.
Perfluorocarbons, also known as ____, have been used for coatings, insulation, computer parts, cosmetics, and propellants.
PFCs
What does the image depict in the context of environmental toxicology?
Potential routes of exposure to toxins in the environment
Which aspect of antibiotic resistance development in microbes is depicted in this image?
Random genetic mutations create antibiotic-resistant individuals that survive and multiply to develop into an antibiotic-resistant colony.
Include pectins, vitamins (like A, C, and E), and cruciferous vegetables (like cabbage and broccoli) in your diet.
Reduces cancer risk
Reduce the amount of salt and animal fat in your die
Reduces cardiovascular disease
Eat fewer calories and exercise more.
Reduces obesity-related illnesses
Stop drinking alcohol during pregnancy.
Reduces risk of fetal alcohol syndrome
A pandemic is ______.
a worldwide (or very widespread) epidemic
Declines in child mortality are largely a result of ______.
better nutrition educating women improved sanitation
The selective absorption and storage of a great variety of molecules inside cells and tissues at levels that are higher than in the environment is called ______.
bioaccumulation
Rank the order of the following causes of death, putting the lowest risk of death for a person in the United States on bottom and the highest risk of death at the top.
cancer car accidents drowning dog attacks
Debates in establishing environmental health policy include whether to ______.
demand protection from every potentially harmful contaminant or accept some exposure as our bodies can repair some damage establish acceptable toxin levels at the highest amount that does not cause measurable effects or as low as technically feasible
The heaviest burden of illness is borne by ______.
developing countries where many people cannot afford adequate health care or to live in a healthy environment
Microbes acquire resistance to antibiotics through different processes that include random mutations and ____ reproduction.
sexual
The World Health Organization's definition of health includes ______ wellbeing.
social mental physical
Persistence of chemicals can be a concern for health because such ______.
stable chemicals are resistant to degradation and can cause problems long after application and far from the sites where they were originally used
Persistent organic pollutants (POPs) are a concern because being ______.
stable, they do not degrade easily and have become extremely widespread in the environment
In environmental toxicity studies, when an interaction between two substances results in one of them exacerbating the effects of another by 20-fold it is called a(n) ______ interaction.
synergistic
Bioaccumulation is ______.
the selective absorption and storage of a great variety of molecules inside cells at levels that are higher than the environment
Poisons that are produced naturally are called ____ substances.
toxic
Allergens are substances that affect us by ______.
triggering a response in our immune systems
Differences in physiology, metabolism, and body size result in species reacting ______ to a specific compound, which makes human risk difficult to estimate.
very differently
Setting environmental health policy is challenging because ______.
we are exposed to many sources of harm, and it is difficult to separate the effects of different hazards in order to evaluate their risks accurately