ENVS 4113 Midterm Flashcards
1
Q
What is the primary purpose of FIFRA?
A
The primary purpose of FIFRA is to establish a regulatory framework for the sale and use of pesticides to protect applicators, consumers, and the environment.
2
Q
Who is responsible for administering and regulating FIFRA?
A
FIFRA is administered and regulated by the U.S. Environmental Protection Agency (EPA) and state environmental agencies.
3
Q
What significant change occurred in 1972 regarding FIFRA?
A
In 1972, the Federal Environmental Pesticide Control Act (FEPCA) significantly revised FIFRA, expanding the EPA’s authority and emphasizing the protection of human health and the environment.
4
Q
What was the first pesticide legislation in the United States?
A
The Federal Insecticide Act of 1910 was the first pesticide legislation, focusing on protecting consumers from fraudulent and adulterated products.
5
Q
How did pesticide use change after World War II?
A
After World War II, pesticide use increased from 100 million pounds in 1945 to over 300 million pounds by 1950 due to newly discovered insecticidal properties of chemicals.
6
Q
What are the main goals of the Endangered Species Act in relation to pesticides?
A
The main goals are to ensure that the registration and use of pesticides do not harm endangered and threatened animals and their habitats.
7
Q
What is required for a pesticide to be registered under FIFRA?
A
A pesticide must undergo over 120 tests to assess its safety and effectiveness, and only about 1 in 139,000 test compounds make it through to registration.
8
Q
What is a “restricted-use” pesticide?
A
A restricted-use pesticide is one that is deemed too hazardous for general use and is available only to certified applicators.
9
Q
What significant revision did the 1972 FEPCA amendment contribute to FIFRA?
A
The 1972 FEPCA amendment shifted the regulatory responsibility from the USDA to the EPA and required the EPA to assess pesticides’ risks against their benefits.
10
Q
How are the risks and benefits of pesticides evaluated under FIFRA?
A
The EPA must weigh the potential risks posed by pesticides to humans, the environment, and wildlife against their agricultural and economic benefits.
11
Q
What does the term “pesticide” include according to FIFRA?
A
According to FIFRA, the term “pesticide” includes any substance or mixture of substances intended for preventing, destroying, repelling, or mitigating any pest, as well as substances intended for use as a plant regulator, defoliant, or desiccant.
12
Q
What is the significance of the 1988 amendments to FIFRA?
A
The 1988 amendments to FIFRA required the re-registration of pesticides registered before 1984 to ensure they meet current health and safety standards.
13
Q
What does the Food Quality Protection Act (FQPA) of 1996 require?
A
The FQPA of 1996 requires that all pesticides cause no harm to infants, children, and sensitive individuals within “reasonable certainty” and mandates a 15-year cycle for pesticide review.
14
Q
How does the EPA handle special reviews of pesticides under FIFRA?
A
If new information suggests adverse side effects, the EPA may conduct a special review to assess the risks and benefits of continued use of the pesticide and may amend or cancel the registration.
15
Q
What is the role of the Federal Food, Drug, and Cosmetic Act (FFDCA) in pesticide regulation?
A
Under FFDCA, the EPA regulates the amount of pesticide residues on or in food, establishing “tolerance levels” to ensure they are safe for consumption.
16
Q
What does the Pesticide Registration Improvement Act (PRIA) aim to achieve?
A
PRIA aims to ensure a smooth implementation of pesticide rules and regulations, including the process of approving pesticide registrations and collecting maintenance fees.
17
Q
How does FIFRA define a “new animal drug” in relation to pesticides?
A
FIFRA excludes “new animal drugs” as defined in section 321(w) of title 21 from the term “pesticide,” focusing on substances intended for pest control rather than veterinary medicine.
18
Q
What is the goal of the Endangered Species Act regarding pesticides?
A
The goal is to protect endangered and threatened species from potential dangers posed by pesticides, requiring the EPA to consider these risks during the pesticide registration process.
19
Q
What is the significance of pesticide labels under FIFRA?
A
Pesticide labels, created upon registration, instruct users on proper usage to maximize effectiveness and minimize risks to humans and the environment. Misuse can lead to liability for negative consequences.
20
Q
How does FIFRA address the distribution and use of “restricted-use” pesticides?
A
FIFRA establishes a certification system for applicators wishing to purchase and use restricted-use pesticides, ensuring they are properly trained to handle these more hazardous substances.
21
Q
What is the definition of “Risk” in the context of chemical risk assessment?
A
Risk = Hazard x Exposure.
22
Q
What does “Hazard” refer to in chemical safety?
A
The built-in property of a chemical’s potential to cause adverse effects to an organism, system or population when exposed to it.
23
Q
What are the three main steps of chemical risk assessment?
A
Hazard characterization, Exposure assessment, Risk characterization.
24
Q
Define “Exposure” in terms of chemical risk.
A
The amount of chemical present and the degree of contact with a system or organism.
25
What is hazard characterization?
Determining the relationship between the magnitude of exposure to a hazard and the probability and severity of adverse effects.
26
What is involved in exposure assessment?
Identifying and quantifying how much exposure to a chemical actually occurs.
27
What is risk characterization?
Combining the information from the hazard characterization and the exposure assessment in order to form a conclusion about the nature and magnitude of risk, and, if indicated, implement additional risk management measures. (Combining hazard and exposure information to conclude the nature and magnitude of risk).
28
What is LD50?
The dose of a chemical that is lethal to 50% of the test population.
29
What is the Risk Characterization Ratio (RCR)?
A ratio of the exposure estimate to the Derived No-Effect Level (DNEL), used to assess risk acceptability.
30
Define NOAEL.
No Observed Adverse Effect Level - the highest exposure level at which there are no significant increases in frequency or severity of adverse effects in the exposed population compared to control.
31
What is acute toxicity?
The adverse effects of a substance that result from a single exposure or multiple exposures in a short period of time.
32
Define carcinogenicity in toxicology.
The ability of a substance to cause cancer.
33
What is the goal of ecotoxicology?
To study the effects of toxic chemicals on biological organisms, especially at the population, community, ecosystem, and biosphere levels.
34
Define NOEC in ecotoxicology.
No Observed Effect Concentration - the concentration below which an unacceptable effect is unlikely to be observed.
35
GHS Classification Criteria
Globally Harmonized System of Classification and Labeling Chemicals - criteria used to determine the nature and the relative severity of the hazard of a chemical substance or mixture
36
What is Toxicology?
Defined as the study of the adverse effects of chemicals or physical agents on living organisms.
37
What is Simpson’s Rule used for?
Numerical integration, specifically for approximating definite integrals.
38
What is truncation error?
Truncation error is the difference between an actual and a truncated, or cut-off value. A truncated quantity is represented by a numeral with a fixed number of allowed digits, with any excess digits chopped off.
39
Define "round-off error".
The difference between an approximation of a number used in computation and its exact value.
40
What is the purpose of REACH regulation?
To improve the protection of human health and the environment through the better and earlier identification of the intrinsic properties of chemical substances.
41
What does GHS stand for and what is its purpose?
Globally Harmonized System of Classification and Labeling of Chemicals, aimed at harmonizing hazard classification and communication.
42
Types of Toxicology Studies?
Acute Toxicity, Skin and Eye Irritation, Sensitization, Repeated Dose Toxicity, Mutagenicity and genotoxicity, Reproductive and developmental toxicity, carcinogenicity, toxicokinetics.
43
Types of Acute Toxicity?
Oral, Inhalation, Dermal
44
Type of Sensitization studies?
Skin, Respiratory
45
Type of Repeated Dose Toxicity Studies?
28d, 90d, Chronic
46
47
48
How is DNEL used in risk assessment?
To assess the risk to human health by comparing the level of exposure to the DNEL.
49
What determines a chemical's persistence in the environment?
The chemical's half-life (DT50), indicating the time it takes for half of the substance to degrade.
50
What does DNEL stand for in chemical risk assessment?
Derived No-Effect Level.
51
What is the significance of LD50 in toxicology?
LD50 is the lethal dose that kills 50% of the test population, indicating acute toxicity.
52
What does NOAEL represent?
No Observed Adverse Effect Level - the highest exposure level at which no significant adverse effects are observed.
53
Define Exposure in chemical risk assessment.
The degree of contact with a chemical substance.
54
What is the goal of ecotoxicology?
To study the effects of chemicals on ecosystems and organisms at various biological levels.
55
Define Hazard in the context of chemical safety.
The inherent property of a chemical to cause adverse effects.
56
What is REACH, and what is its purpose?
Registration, Evaluation, Authorisation, and Restriction of Chemicals; aims to protect human health and the environment from hazardous chemicals.
57
What does LC50 measure in toxicology?
The lethal concentration that kills 50% of the test population, used for assessing inhalation toxicity.
58
What does GHS stand for, and why is it important?
Globally Harmonized System of Classification and Labelling of Chemicals; important for harmonizing hazard communication.
59
Describe the concept of "Risk Characterization".
The process combining hazard and exposure assessment to estimate the risk. Combining the information from the hazard characterization and the exposure assessment in order to form a conclusion about the nature and magnitude of risk, and, if indicated, implement additional risk management measures.
60
What is the purpose of the NOEC value in ecotoxicology?
No Observed Effect Concentration; the highest concentration that does not result in observable adverse effects on the environment.
61
Explain the term "Round-off Error" in numerical analysis.
The error resulting from the approximation of a number due to limited precision in its representation.
62
What is a Risk Quotient (RQ), and how is it calculated?
RQ = Estimated Environmental Concentration (EEC) / Ecotoxicity Effect Endpoint; used to assess ecological risk.
63
Describe the term "Acute Toxicity".
The adverse effects of a substance that result from a single exposure or multiple exposures in a short period.
64
What does the term "Carcinogenicity" mean in toxicology?
The ability of a substance to cause cancer.
65
Explain the purpose of a Margin of Exposure (MOE) calculation.
To assess the safety of a substance by comparing the no-observed-adverse-effect level to the estimated exposure level.
66
What does the term "Persistence" refer to in environmental chemistry?
The time it takes for half of the substance to degrade in the environment, indicated by its half-life (DT50).
67
Define "Hazard Characterization" in the context of chemical risk assessment.
The dose-response determination (LD50/LC50, NOAEL, T25, EC50, NOEC, etc) determines the relationship between the magnitude of exposure to a hazard with the probability and severity of adverse effects.
68
What does EC50 represent in an ecotoxicology study?
The concentration of a substance that causes a 50% reduction in a quantifiable biological function (e.g., growth or reproduction) in a test population.
69
What is the purpose of "Exposure Assessment"?
Identifying the extent to which an exposure actually occurs. Exposure levels are usually estimated or measured.
70
Explain what a "Derived Minimum Effect Level" (DMEL) refers to.
A level of chemical exposure below which a human population (including sensitive subgroups) could be safely exposed over a lifetime without appreciable health risk.
71
What is "Numerical Integration" and why is it used?
A method to approximate the value of integrals, used when an analytic solution is difficult or impossible to obtain.
72
Describe "Chronic Toxicity" and how it is assessed.
The adverse effects of a substance after prolonged or repeated exposure, typically assessed over a significant portion of the organism's lifespan.
73
What does "Bioaccumulation" refer to in environmental science?
The process by which a chemical concentration in an organism exceeds that in its environment due to absorption and accumulation over time.
74
Define "Mutagenicity" in the context of toxicological studies.
The property of a chemical agent to cause mutations, which are permanent changes in the DNA sequence of an organism.
75
What is "Environmental Fate Modeling" used for?
To predict the distribution, concentration, and persistence of chemicals in the environment through mathematical models.
76
Explain the significance of "Safety Factor" in risk assessment.
A multiplicative factor applied to account for uncertainty in the extrapolation from animal studies to humans, aiming to ensure the protection of human health.
77
Convection and Advection:
These processes describe the movement of pesticides through the transport of heated fluid (like water) and the bulk movement of substances by currents in the fluid, respectively.
78
Dispersion and Diffusion
These processes describe the spread of pesticide particles from areas of high concentration to low concentration through random motion or the mixing of substances within a fluid.
79
Pesticides enter drinking water sources through several pathways, including:
Agricultural runoff, soil erosion, leaching into groundwater, and drift from aerial and ground application methods.
80
Water and pesticide movement is significantly influenced by natural forces such as
Water flow and wind
81
Use of models:
Models are crucial for estimating pesticide exposure in the environment. They help interpret field studies, extrapolate findings to different conditions, compare pesticides, and evaluate sources of uncertainty. Models are cost-effective alternatives to extensive field or laboratory studies.
82
Convection
involves the movement of heat through fluids (air or water), affecting how substances like pesticides can be distributed within these mediums.
83
Advection
is the process of transporting a substance by the bulk movement of water, such as the flow of pollutants in a river.
84
Dispersion
describes the spread of matter from high to low concentration areas, crucial for understanding how pollutants disperse in water bodies.
85
Diffusion
is the process where particles spread out, leading to a uniform distribution within a medium, such as water.
86
Convection–diffusion equation
Combines diffusion and convection processes, providing a framework for modeling the transport of particles, energy, or other quantities in a system.
87
Pesticide modeling and mass balance concepts emphasize
that the total mass of pesticides within a model system remains constant, adhering to the law of conservation of mass. This principle is critical for accurately modeling pesticide behavior in the environment.
88
Environmental fate parameters such as
molecular weight, solubility, and adsorption/desorption characteristics are key to understanding how pesticides interact with different environmental compartments and their potential for movement and transformation.
89
Pesticide degradation
is an essential aspect of modeling, with various processes (such as photolysis and microbial degradation) influencing how quickly pesticides break down in the environment.
90
What are the main pathways through which pesticides enter drinking water sources?
Agricultural runoff, soil erosion, leaching into groundwater, and drift from aerial and ground application methods.
91
What is the primary factor affecting pesticide movement in the environment?
Water flow.
92
Why are models used to estimate pesticide exposure in the environment?
To interpret field studies, extrapolate to different conditions, compare pesticides, evaluate uncertainty, and as a cost-effective alternative to field/laboratory studies.
93
At what scales is the hydrologic cycle crucial for understanding pesticide transport?
Watershed and field scale.
94
What role does convection play in the distribution of pesticides in the environment?
It involves the movement of heat through fluids (air or water), affecting pesticide distribution.
95
What is advection in the context of environmental science?
The transport of a substance by the bulk movement of water, crucial for understanding pollutant flow in rivers.
96
How does dispersion affect pollutant distribution in water bodies?
It describes the spread of matter from high to low concentration areas, essential for understanding pollutant dispersal.
97
What does the diffusion process entail in environmental studies?
The spread of particles leading to a uniform distribution within a medium like water.
98
What does the convection–diffusion equation model in environmental studies?
The combined effects of diffusion and convection in transporting particles or energy in a system.
99
Why is sediment transport significant in surface water exposure modeling for pesticides?
It influences how pesticide particles attached to soil are moved by water into surface waters.
100
What does the principle of mass conservation state regarding pesticide modeling?
The total mass of pesticides remains constant within a model system, adhering to the law of conservation of mass.
101
Which environmental fate parameters are crucial for understanding pesticide behavior?
Molecular weight, solubility, and adsorption/desorption characteristics.
102
What processes influence pesticide degradation in the environment?
Photolysis, microbial degradation (aerobic and anaerobic metabolism), hydrolysis, and volatility.
103
How does hydrology contribute to pesticide movement and distribution?
Hydrology determines water flow patterns, which are primary carriers of pesticides in the environment.
104
What natural forces are primarily responsible for pesticide movement in the environment?
Water and wind.
105
What is the purpose of the SETBACK model in pesticide application?
To estimate the setback distance from drinking water intakes and minimum holding period for aquatic herbicide applications.
106
How do pesticides interact with soil particles through adsorption/desorption processes?
Pesticides are dispersed between solid matter and water, influenced by the soil's organic matter content.
107
How does a pesticide's solubility affect its environmental fate and transport?
Water-soluble pesticides tend to remain at the surface, while insoluble ones penetrate into the soil's hydrophobic interior.
108
Why is organic matter significant in the sorption of pesticides to soil?
It acts as a major retention site, influencing the distribution between soil and soil water.
109
What is the significance of modeling pesticide degradation in environmental fate studies?
To predict how quickly pesticides break down in the environment, affecting their longevity and potential for contamination.
110
Why is pesticide volatility important in assessing environmental fate?
High volatility pesticides can evaporate into the atmosphere, affecting their distribution and degradation pathways.
111
What are some methods through which pesticides are applied that can affect their environmental dispersion?
Aerial application, ground spraying, orchard airblast, and chemigation.
112
How does hydrolysis contribute to pesticide degradation in the environment?
It involves a chemical reaction with water to break down pesticide molecules, often dependent on pH levels.
113
How does wind influence pesticide application and potential environmental contamination?
Wind can carry pesticides away from target areas, leading to unintended exposure and drift into sensitive environments.
114
Why is the content of organic matter in soil crucial for pesticide fate modeling?
Organic matter content influences pesticide adsorption, affecting mobility and degradation rates in soils.
115
What factors contribute to pesticide leaching into groundwater?
Soil permeability, pesticide solubility, and the presence of preferential flow paths such as macropores.
116
What role does photolysis play in the degradation of pesticides in the environment?
Photolysis involves the breakdown of pesticides by sunlight, affecting degradation rates on soil surfaces and in water.
117
How are pesticide sorption coefficients (Kd and Koc) used in environmental fate studies?
They quantify the extent to which pesticides bind to soil particles, influencing mobility and bioavailability.
118
How does climate affect the transport and transformation of pesticides in the environment?
Temperature and precipitation patterns influence volatilization, degradation rates, and the potential for runoff and leaching.
119
Why is understanding pesticide transport and degradation important for resistance management?
It helps predict environmental concentrations over time, informing strategies to mitigate resistance development in target pests.
120
What is biodegradation, and why is it significant for pesticide fate in the environment?
Biodegradation is the breakdown of pesticides by living organisms, significant for reducing pesticide persistence and potential toxicity in the environment.
121
What does the term "half-life" refer to in the context of pesticides in the environment?
The time required for the concentration of a pesticide to decrease by half through degradation processes.
122
What do pesticide adsorption isotherms describe?
The relationship between the concentration of pesticides in the soil solution and the amount adsorbed by the soil at equilibrium.
123
How does Integrated Pest Management (IPM) reduce the need for chemical pesticides?
IPM uses a combination of biological, cultural, physical, and chemical tools to manage pests in an environmentally and economically sustainable way, reducing reliance on chemical pesticides.
124
How does the formulation of a pesticide influence its environmental fate?
The formulation affects solubility, volatility, and adsorption properties, thereby influencing its mobility, persistence, and degradation patterns.
125
Why is the study of pesticides' effects on non-target species important?
To assess and mitigate unintended impacts on biodiversity, including beneficial insects, aquatic organisms, and wildlife.
126
What impact does pesticide runoff have on surface water quality?
Pesticide runoff can lead to contamination of rivers, lakes, and streams, affecting aquatic life and potentially entering human drinking water sources.
127
How do pesticide regulations contribute to environmental safety?
Regulations ensure the safe use, storage, and disposal of pesticides to minimize environmental contamination and protect human health.
128
What is the purpose of monitoring pesticide residues in the environment?
To track the presence and concentration of pesticides in various environmental compartments, assessing compliance with safety standards and identifying potential risks.
129
How does Integrated Pest Management (IPM) reduce the need for chemical pesticides?
IPM uses a combination of biological, cultural, physical, and chemical tools to manage pests in an environmentally and economically sustainable way, reducing reliance on chemical pesticides.
130
What are the environmental implications of pesticide resistance?
Resistance can lead to increased pesticide use, greater environmental contamination, and loss of biodiversity as more potent chemicals or increased quantities are required to control resistant pests.
131
How does soil pH affect pesticide degradation?
Soil pH can influence the microbial activity and chemical reactions responsible for pesticide breakdown, affecting degradation rates.
132
What is the Pesticide Mobility Index (PMI), and why is it important?
PMI predicts a pesticide's potential to move within the soil profile and reach groundwater, helping assess environmental contamination risk.
133
What role do buffer zones play in pesticide application?
Buffer zones protect sensitive areas (e.g., water bodies, residential areas) from pesticide drift and runoff, reducing environmental and human health risks.
134
What is bioaccumulation, and how does it relate to pesticides?
Bioaccumulation refers to the buildup of pesticides in an organism's tissues, often through the food chain, leading to potential toxic effects.
135
How can pesticides impact soil microbiota?
Pesticides can alter the diversity and function of soil microbial communities, affecting nutrient cycling, soil fertility, and ecosystem health.
136
How does the depth of the water table influence pesticide leaching risks?
Shallow water tables are at higher risk for pesticide contamination from leaching, especially in permeable soils or with highly soluble pesticides.
137
Why is pesticide use reporting important for environmental monitoring?
Reporting enables tracking of pesticide application rates and patterns, informing risk assessments and mitigation strategies for environmental protection.
138
What techniques are used for pesticide remediation in contaminated environments?
Techniques include bioremediation, phytoremediation, and advanced chemical treatments to reduce or eliminate pesticide residues.
139
What are endocrine-disrupting pesticides, and why are they a concern?
These pesticides can interfere with hormone systems in wildlife and humans, causing developmental, reproductive, neurological, and immune issues.
140
What are sustainable practices for pesticide disposal?
Sustainable practices include proper containment, degradation, recycling of containers, and following guidelines to minimize environmental impact.
141
FFDCA
Federal Food, Drug, and Cosmetic Act
142
FEPCA
Federal Environmental Pesticide Control Act
143
FIFRA
Federal Insecticide, Fungicide, and Rodenticide Act
144
PRIA
Pesticide Registration Improvement Act
145
FQPA
Food Quality Protection Act
146
FIA
Federal Insecticide Act
147
RCR
Risk Characterization Ratio – ratio of the exposure estimate to the DNEL
148
NOAEL
No Observed Adverse Effect Level
149
DNEL
Derived No-Effect Level
150
NOEC
No Observed Effect Concentration
151
REACH
Registration, Evaluation, Authorization, and Restriction of Chemicals
152
GHS
Globally Harmonized System of Classification and Labeling of Chemicals
153
NOAEL
No Observed Adverse Effect Level
154
RQ
Risk Quotient = EEC / Ecotoxicity Effect Endpoint
155
EEC
Estimated Environmental Concentration
156
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