Module 10 (Toxicology and Environmental Health Problems) Flashcards
(99 cards)
1
Q
What are Trihalomethanes?
A
Trihalomethanes (THMs) are the result of a reaction between the chlorine used for disinfecting tap water and natural organic matter in the water. At elevated levels, THMs have been associated with negative health effects such as cancer and adverse reproductive outcomes.
2
Q
What activities are most likely to increase THM blood levels in humans?
A
Showering, bathing, and washing dishes
3
Q
What is a toxic substance?
A
a substance that can cause adverse health effects
4
Q
What is a toxin?
A
A toxic substance that is produced naturally
5
Q
What is a toxicant?
A
A chemical that can harm humans, animals, or plants that is produced by (or is a byproduct of) human activities
6
Q
What is toxicity?
A
the degree to which a substance is poisonous or can cause injury
7
Q
What are toxic effects?
A
health effects that occur due to exposure to a toxic substance
8
Q
What is potable water?
A
Drinkable water / water that is safe to drink
9
Q
What does the adage “the dose makes the poison” mean?
A
“The dose makes the poison” is an adage intended to indicate a basic principle of toxicology (all substances can be poisonous at the “right” dose). It is credited to Paracelsus who expressed the classic toxicology maxim “All things are poison, and nothing is without poison; the dosage alone makes it so a thing is not a poison.”
10
Q
What is a threshold dose?
A
a dose below which the effect does not occur.
11
Q
In terms of threshold dose, what do NOAEL and LOAEL mean?
A
NOAEL: no observed adverse affect level (same as the threshold dose)
LOAEL: lowest observed adverse effect level
12
Q
What are examples of diseases caused by environmental substances?
A
Coal dust & lung disease
DDT & Reproductive Issues
Ethanol (Alcohol) & Teratogenic Issues
Lead (Neurological Effects)
Beryllium (Hypersensitivity, Immunosuppression)
Formaldehyde (cancer)
13
Q
What populations are most sensitive to environmental exposures?
A
low income
minorities
indigenous peoples
children
elderly
disabled
pregnant women
women of childbearing age
14
Q
What individual factors affect susceptibility to environmental exposures?
A
nutrition
genetic factors
metabolism
low SES
geography
gender
age
15
Q
What are endocrine disruptors?
A
Endocrine disruptors are natural or man-made chemicals that may mimic or interfere with the body’s hormones, known as the endocrine system.
Examples: pharmaceuticals, Dioxin, PCBs, certain pesticides, Bisphenol A (BPA), and PFAS
16
Q
What is a carcinogen?
A
A carcinogen is a substance, organism or agent capable of causing cancer
17
Q
What are some of the best ways to avoid excessive exposure to PFAS?
A
Avoid nonstick cookware
Eat organic
Avoid frozen produce
Avoid prepackaged foods
18
Q
What natural study was conducted during the 1996 Olympics in Atlanta?
A
Reducing traffic and changing commuter behaviors also reduced pollution and asthma
19
Q
What is selective toxicity?
A
“Selective toxicity” means that a chemical will produce injury to one kind of living matter without harming another form of life, even though the two may exist close together.
20
Q
How does toxicity develop?
A
Before toxicity can develop, a substance must come into contact with a body surface such as skin, eye or mucosa of the digestive or respiratory tract. The dose of the chemical, or the amount one comes into contact with, is important when discussing how “toxic” an substance can be.
21
Q
What is a dose?
A
The dose is the actual amount of a chemical that enters the body. The dose received may be due to either acute (short) or chronic (long-term) exposure. An acute exposure occurs over a very short period of time, usually 24 hours. Chronic exposures occur over long periods of time such as weeks, months, or years. The amount of exposure and the type of toxin will determine the toxic effect.
22
Q
What is dose response?
A
Dose-response is a relationship between exposure and health effect, that can be established by measuring the response relative to an increasing dose. This relationship is important in determining the toxicity of a particular substance (2). It relies on the concept that a dose, or a time of exposure (to a chemical, drug, or toxic substance), will cause an effect (response) on the exposed organism. Usually, the larger or more intense the dose, the greater the response, or the effect. This is the meaning behind the statement “the dose makes the poison.”
23
Q
What is a sensitive sub population?
A
A sensitive sub-population describes those persons who are more at risk from illness due to exposure to hazardous substances than the average, healthy person. These persons usually include the very young, the chronically ill, and the very old. It may also include pregnant women and women of childbearing age. Depending on the type of contaminant, other factors (e.g., age, weight, lifestyle, sex) could be used to describe the population.
24
Q
What is meant by individual susceptibility?
A
This term describes the differences in types of responses to hazardous substances, between people. Each person is unique, and because of that, there may be great differences in the response to exposure. Exposure in one person may have no effect, while a second person may become seriously ill, and a third may develop cancer.
25
What is environmental toxicology?
is concerned with the study of chemicals that contaminate food, water, soil, or the atmosphere. It also deals with toxic substances that enter bodies of waters such as lakes, streams, rivers, and oceans. This sub-discipline addresses the question of how various plants, animals, and humans are affected by exposure to toxic substances.
26
What is industrial / occupational toxicology?
is concerned with health effects from exposure to chemicals in the workplace. This field grew out of a need to protect workers from toxic substances and to make their work environment safe. Occupational diseases caused by industrial chemicals account for an estimated 50,000 to 70,000 deaths, and 350,000 new cases of illness each year in the United States (1).
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What is regulatory toxicology?
gathers and evaluates existing toxicological information to establish concentration-based standards of “safe” exposure. The standard is the level of a chemical that a person can be exposed to without any harmful health effects.
28
What is food toxicology?
is involved in delivering a safe and edible supply of food to the consumer. During processing, a number of substances may be added to food to make it look, taste, or smell better. Fats, oils, sugars, starches and other substances may be added to change the texture and taste of food. All of these additives are studied to determine if and at what amount, they may produce adverse effects. A second area of interest includes food allergies. Almost 30% of the American people have some food allergy. For example, many people have trouble digesting milk, and are lactose intolerant. In addition, toxic substances such as pesticides may be applied to a food crop in the field, while lead, arsenic, and cadmium are naturally present in soil and water, and may be absorbed by plants. Toxicologists must determine the acceptable daily intake level for those substances.
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What is clinical toxicology?
is concerned with diseases and illnesses associated with short term or long term exposure to toxic chemicals. Clinical toxicologists include emergency room physicians who must be familiar with the symptoms associated with exposure to a wide variety of toxic substances in order to administer the appropriate treatment.
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What is Descriptive Toxicology?
is concerned with gathering toxicological information from animal experimentation. These types of experiments are used to establish how much of a chemical would cause illness or death. The United States Environmental Protection Agency (EPA), the Occupational Safety and Health Administration (OSHA), and the Food and Drug Administration (FDA), use information from these studies to set regulatory exposure limits.
31
What is forensic toxicology?
is used to help establish cause and effect relationships between exposure to a drug or chemical and the toxic or lethal effects that result from that exposure.
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What is analytical toxicology?
identifies the toxicant through analysis of body fluids, stomach content, excrement, or skin.
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What is mechanistic toxicology?
makes observations on how toxic substances cause their effects. The effects of exposure can depend on a number of factors, including the size of the molecule, the specific tissue type or cellular components affected, whether the substance is easily dissolved in water or fatty tissues, all of which are important when trying to determine the way a toxic substance causes harm, and whether effects seen in animals can be expected in humans.
34
What are the classifications of toxic agents?
Heavy metals
Solvents and vapors
Radiation and Radioactive Materials
Dioxins / Furans
Pesticides
Plant Toxins
Animal Toxins
Sub Categories
General Classifications
35
What are heavy metals?
Metals differ from other toxic substances in that they are neither created nor destroyed by humans. Their use by humans plays an important role in determining their potential for health effects. Their effect on health could occur through at least two mechanisms: first, by increasing the presence of heavy metals in air, water, soil, and food, and second, by changing the structure of the chemical. For example, chromium III can be converted to or from chromium VI, the more toxic form of the metal.
36
What are solvents and vapors?
Nearly everyone is exposed to solvents. Occupational exposures can range from the use of “white-out” by administrative personnel, to the use of chemicals by technicians in a nail salon. When a solvent evaporates, the vapors may also pose a threat to the exposed population.
37
What is radiation / radioactive material?
Radiation is the release and propagation of energy in space or through a material medium in the form of waves, the transfer of heat or light by waves of energy, or the stream of particles from a nuclear reactor (3).
38
WHat are Dioxins / Furans?
Dioxin, (or TCDD) was originally discovered as a contaminant in the herbicide Agent Orange. Dioxin is also a by-product of chlorine processing in paper producing industries.
39
What are pesticides?
The EPA defines pesticide as any substance or mixture of substances intended to prevent, destroy, repel, or mitigate any pest. Pesticides may also be described as any physical, chemical, or biological agent that will kill an undesirable plant or animal pest (2).
40
What are plant toxins?
Different portions of a plant may contain different concentrations of chemicals. Some chemicals made by plants can be lethal. For example, taxon, used in chemotherapy to kill cancer cells, is produced by a species of the yew plant.
41
What are animal toxins?
These toxins can result from venomous or poisonous animal releases. Venomous animals are usually defined as those that are capable of producing a poison in a highly developed gland or group of cells, and can deliver that toxin through biting or stinging. Poisonous animals are generally regarded as those whose tissues, either in part or in their whole, are toxic.
42
What are the subcategories of Toxic Substance Classifications?
Effect on target organs (liver, kidney, hematopoietic system),
Use (pesticide, solvent, food additive),
Source of the agent (animal and plant toxins),
Effects (cancer mutation, liver injury),
Physical state (gas, dust, liquid),
Labeling requirements (explosive, flammable, oxidizer),
Chemistry (aromatic amine, halogenated hydrocarbon), or
Poisoning potential (extremely toxic, very toxic, slightly toxic)
43
What are general Toxic Substance categories of interest to certain communities?
Air pollutants
Occupation-related
Acute and chronic poisons
44
What are the main Toxicological Information Sources
The Agency for Toxic Substances and Disease Registry (ATSDR)
US Environmental Protection Agency (EPA)
Centers for Disease Control and Prevention (CDC)
Nuclear Regulatory Commission (NRC)
Food and Drug Administration (FDA)
American Conference of Governmental Industrial Hygienists (ACGIH)
Electronic Databases
45
What is the The Agency for Toxic Substances and Disease Registry (ATSDR) ?
ATSDR is part of the U.S. Department of Health and Human Services. It was created by Congress in 1980 to provide health-based information for use in the cleanup of chemical waste disposal sites mandated by the Comprehensive Environmental Response, Compensation, and Liability Act (CERCLA). As the lead agency for implementing the health-related guidelines of CERCLA, ATSDR assesses the presence and nature of health hazards at specific Superfund Sites, to help prevent or reduce further exposure and the illnesses that result from such exposures, and to expand the knowledge-base about health effects from exposure to hazardous substances.
46
What is the US Environmental Protection Agency (EPA) in terms of toxicology ?
EPA is responsible for a number of activities, including enforcing federal laws designed to protect human health and the environment.
47
What is the CDC in terms of toxicology?
CDC is an agency in the Department of Health and Human Services, its mission is to promote health and quality of life by preventing and controlling disease, injury, and disability. In the past, the CDC has focused on the study and prevention of infectious diseases such as malaria and smallpox. However, now its responsibilities have enlarged to include environmental and occupational hazards.
48
What is the Nuclear Regulatory Commission?
NRC, established in 1974, regulates the use of nuclear materials for commercial, industrial, academic, and medical purposes. This includes regulating nuclear power plants, nuclear materials used in the diagnosis and treatment of cancer, and nuclear materials used in smoke detectors. NRC also regulates non-power research, test and training reactors; nuclear fuel cycle facilities (the production of nuclear fuel); and the transport, storage, and disposal of nuclear materials and waste. Like OSHA and EPA, NRC obtains and evaluates information about acceptable exposure levels for workers handling nuclear materials.
49
What is the Food and Drug Administration in terms of toxicology?
FDA promotes and protects the public health by helping safe and effective products reach the market in a timely way, and monitoring products for continued safety after they are in use.
50
What is the
ACGIH is a professional organization that produces a listing of Threshold Limit Values (TLV) and Biological Exposure Indices (BEI) for several hundred chemicals, updating them every year. BEIs are recommended maximum concentrations of various types of toxic substances, and are guidelines to evaluate the potential health hazards associated with exposure. The maximum concentration may be measured in blood, urine, or exhaled air. The TLVs are guidelines for occupational exposure to hazardous chemicals and are published in a booklet called Threshold Limit Values (TLVs) for Chemical Substances and Physical Agents and Biological Exposure Indices (6).
51
What are the recommended electronic databases for Toxicology?
Toxicology Data Network (TOXNET)
CHEMTREC (Chemical Transportation Emergency Center)
Material Safety Data Sheets (MSDS) via the OSHA website
Hazardous Substances and Health Effects Database (HazDat) (available via ATSDR website)
52
What is source water?
untreated water used to produce drinking water
53
What is surface water?
all water on the surface as opposed to water from the subsurface or ground water
54
How much does water fluoridization effect dental health?
field trials in the 1940s indicated a 50-70% reduction in dental cavities
Currently, numbers are estimated at about 25% reduction
55
What are water disinfection byproducts?
Disinfection by-products (DBPs) are formed when disinfectants like chlorine interact with natural organic materials in water, such as in chlorinated drinking water and chlorine-treated swimming pools. DBPs can be found in the air during activities such as showering, bathing, dishwashing, and swimming. The most common type of DBPs are trihalomethanes (THMs).
56
What are the most common methods of wastewater treatment?
Municipal Wastewater treatment (serves 75% of the US population)
Onsite systems like Septic Tanks (serve 20% of the US population)
57
Describe the Air Quality Index
58
Describe Atlanta Air Quality
59
Describe the system of environmental toxins and exposure routes
60
Describe environmental air exposures
61
Describe the structure of groundwater versus surface
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Describe the general hazardous waste system / continuum
63
Describe the toxicological paradigm
64
Describe the toxicology triad
65
Describe common issues with wastewater (worldwide)
66
Describe common uses of water in the US
67
Describe US water use versus population size
68
Describe the topics covered by the Model Aquatic Health Code
69
What is the Clean Air Act?
The Clean Air Act is the United States' primary federal air quality law, intended to reduce and control air pollution nationwide. Initially enacted in 1963 and amended many times since, it is one of the United States' first and most influential modern environmental laws
70
What are Criteria Air Pollutants?
The Clean Air Act requires EPA to set National Ambient Air Quality Standards (NAAQS) for six common air pollutants (also known as "criteria air pollutants"). These pollutants are found all over the U.S. They can harm your health and the environment, and cause property damage.
They include: particulate matter, sulfur dioxide, carbon monoxide, nitrogen oxides, ozone, and lead
71
What is particulate matter?
Particulate matter contains microscopic solids or liquid droplets that are so small that they can be inhaled and cause serious health problems.
72
What is sulfur dioxide?
Sulfur dioxide or sulphur dioxide is the chemical compound with the formula SO ₂. It is a toxic gas responsible for the odor of burnt matches. It is released naturally by volcanic activity and is produced as a by-product of copper extraction and the burning of sulfur-bearing fossil fuels.
Sulfur dioxide irritates the respiratory tract and increases the risk of tract infections. It causes coughing, mucus secretion and aggravates conditions such as asthma and chronic bronchitis.
73
What is carbon monoxide?
Carbon monoxide is a poisonous, flammable gas that is colorless, odorless, tasteless, and slightly less dense than air.
CO is found in fumes produced any time you burn fuel in cars or trucks, small engines, stoves, lanterns, grills, fireplaces, gas ranges, or furnaces. CO can build up indoors and poison people and animals who breathe it.
74
What are Nitrogen Oxides?
Nitrogen Oxides are a family of poisonous, highly reactive gases. These gases form when fuel is burned at high temperatures. NOx pollution is emitted by automobiles, trucks and various non-road vehicles (e.g., construction equipment, boats, etc.)
75
What is lead?
Lead is a naturally occurring element found in small amounts in the earth’s crust. While it has some beneficial uses, it can be toxic to humans and animals, causing health effects.
Lead and lead compounds have been used in a wide variety of products found in and around our homes, including paint, ceramics, pipes and plumbing materials, solders, gasoline, batteries, ammunition and cosmetics.
76
What is ozone?
Ozone is an odorless, colorless gas made up of three oxygen molecules (O3) and is a natural part of the environment. It occurs both in the Earth's upper atmosphere, or stratosphere, and at ground level in the lower atmosphere, or troposphere
The ozone layer found high in the upper atmosphere shields us from much of the sun's ultraviolet radiation. However, ozone air pollution at ground level where we can breathe it causes serious health problems. Ozone aggressively attacks lung tissue by reacting chemically with it.
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How is lead harmful to humans?
Effects in kids: Behavior and learning problems
Lower IQ and Hyperactivity
Slowed growth
Hearing Problems
Anemia
Effects in adults: Cardiovascular effects, increased blood pressure and incidence of hypertension;
Decreased kidney function; and
Reproductive problems (in both men and women).
Effects in pregnant women:
Cause the baby to be born too early or too small;
Hurt the baby’s brain, kidney’s, and nervous system;
Increase the likelihood of learning or behavioral problems; and Put the mother at risk for miscarriage.
78
What are EPA Emissions Standards?
Emissions standards set limits on the amount of pollution a vehicle or engine can emit. EPA realizes that to reduce mobile source pollution we must address not only vehicles, engines, and equipment, but also the fuels they use. So we have set sulfur standards for gasoline, on-road diesel fuel, and nonroad diesel fuel.
79
What is the Emergency Planning and Community Right-to-Know Act (EPCRA)?
The Emergency Planning and Community Right-to-Know Act (EPCRA), authorized by Title III of the Superfund Amendments and Reauthorization Act (SARA Title III), was passed in 1986 in response to concerns regarding the environmental and safety hazards posed by the storage and handling of toxic chemicals.
80
What are chlorofluorocarbons (CFCs)?
Chlorofluorocarbons (CFCs) are nontoxic, nonflammable chemicals containing atoms of carbon, chlorine, and fluorine. They are used in the manufacture of aerosol sprays, blowing agents for foams and packing materials, as solvents, and as refrigerants.
Whereas CFCs are safe to use in most applications and are inert in the lower atmosphere, they do undergo significant reaction in the upper atmosphere or stratosphere. In 1974, two University of California chemists, Professor F. Sherwood Rowland and Dr. Mario Molina, showed that the CFCs could be a major source of inorganic chlorine in the stratosphere following their photolytic decomposition by UV radiation. In addition, some of the released chlorine would become active in destroying ozone in the stratosphere2.
81
What is Acid Rain?
Acid rain results when sulfur dioxide (SO2) and nitrogen oxides (NOX) are emitted into the atmosphere and transported by wind and air currents.
Acid rain can be extremely harmful to forests. Acid rain that seeps into the ground can dissolve nutrients, such as magnesium and calcium, that trees need to be healthy. Acid rain also causes aluminum to be released into the soil, which makes it difficult for trees to take up water.
82
How does carbon dioxide affect climate change?
Carbon dioxide in the atmosphere warms the planet, causing climate change. Human activities have raised the atmosphere's carbon dioxide content by 50% in less than 200 years. This is the leading cause of global warming
83
What are greenhouse gases?
Greenhouse gases are the gases in the atmosphere that raise the surface temperature of planets such as the Earth. What distinguishes them from other gases is that they absorb the wavelengths of radiation that a planet emits, resulting in the greenhouse effect. The most common one is carbon dioxide.
Greenhouse gases absorb this infrared radiation and trap its heat in the atmosphere, creating a greenhouse effect that results in global warming and climate change.
84
Describe the EPA's path to cleaner cars
85
What is the Clean Water Act?
The Clean Water Act (CWA) establishes the basic structure for regulating discharges of pollutants into the waters of the United States and regulating quality standards for surface waters. The basis of the CWA was enacted in 1948 and was called the Federal Water Pollution Control Act, but the Act was significantly reorganized and expanded in 1972. "Clean Water Act" became the Act's common name with amendments in 1972.
86
Where does most point source pollution come from?
Municipal sewage and industrial discharges (contaminated waterways)
87
What are examples of nonpoint source pollution within waterways?
contaminants coming from stormwater runoff from farmland, construction sites, and urban streets
88
What is the leading source of water pollution in the US?
Agriculture (soil, manure fertilizers, and pesticides washing into streams and lakes)
89
What is the Safe Drinking Water Act?
The Safe Drinking Water Act (SDWA) was passed by Congress in 1974, with amendments added in 1986 and 1996, to protect our drinking water. Under the SDWA, EPA sets the standards for drinking water quality and monitors states, local authorities, and water suppliers who enforce those standards.
90
What is the Flint Water Crisis?
On April 25, 2014, the City of Flint, Michigan changed their municipal water supply source from the Detroit-supplied Lake Huron water to the Flint River. The switch caused water distribution pipes to corrode and leach lead and other contaminants (potentially including Legionella Bacteria) into municipal drinking water.
91
Is water a limited resource?
However, it is a limited resource; fresh water makes up only about three percent of all water on Earth. Although fresh water is considered a renewable resource, the use of fresh water in some regions exceeds the ability of natural processes to replenish supplies.
92
What is the Clean Water, Clean Sir, and Green Jobs Act?
On November 8, 2022, New Yorkers overwhelming approved a ballot proposition to make $4.2 billion available for environmental and community projects. DEC can access funding to protect water quality, help communities adapt to climate change, improve resiliency and create green jobs.
93
True or False? When lead pipes have been damaged by acidic water, there are anticorrosion chemicals that can be used to ameliorate the problem.
true
94
True or False? The greatest danger with lead pipes in homes comes when the water arriving at the house is acidic.
true
95
True or False? While Americans support most measures to ensure cleaner air, they consistently resist efforts to move them out of their private automobiles.
True
96
What is turbidity?
Turbidity is the cloudiness or haziness of a fluid caused by large numbers of individual particles that are generally invisible to the naked eye, similar to smoke in air. The measurement of turbidity is a key test of both water clarity and water quality.
97
Today, _________________ are the nation's most frequent violators of the Clean Water Act.
sewage systems
98
What is the Montreal Protocol?
The Montreal Protocol is an international treaty designed to protect the ozone layer by phasing out the production of numerous substances that are responsible for ozone depletion. It was agreed on 16 September 1987, and entered into force on 1 January 1989.
99
What are the main 4 exposure routes of toxic substances?
Ingestion
Inhalation
Dermal Contact
External exposure to radioactive chemicals
