Brainscape's Knowledge GenomeTM


Top Flashcards (Certified)
All Flashcards

Pollution & Bioremediation > Midterm > Flashcards

Midterm Flashcards

1
Q

Number of chemicals in commerce?

A

85k-250k

Unclear true number since not all are admitted

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

What is an HPV?

A

High production volume chemicals

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

What is the number of HPVs?

A

3,000

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

How much HPV (percentage wise) have basic risk information? And what is the number of basic screening tests?

A

7%
43% are missing every test
57% have at least one test
There are 6 basic screening tests (called SIDs: screening information dataset)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

How many people have water stress (pollutants) in their local rivers?

A

~ 5,000 mill

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

What are NAQs?

A

National air quality standards

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

How many Americans live in areas that exceed NAQs?

A

1/3rd

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

How many liters of air does a person inhale every day?

A

~11,000

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

How many people die every year due to pollution?

A

~9 mill

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

What is the GBD and how does pollution affect it?

A

Global burden of disease

Inc. due to pollution

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

What does the Lancet Commission (science reports) say about pollution?

A

Inc. GBD (connect multiple exposures to health effects)
It is not being dealt with
Vulnerable groups are disproportionately impacted
There are win-win solutions
Advocates usually skip over the necessary processes

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

What is the dilution paradigm?

A

Solution to pollution is dilution
It was a widespread belief
Ex. factories made tall stacks so smoke would be sent up and disperse in air (created acid rain)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

What is the boomerang paradigm?

A

What is thrown away can come back and hurt you
Precautionary steps should be taken to stop any unknown longterm effects
Ex. Love canal

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

What is DDT?

A

Dichlorodiphenyltrichloroethane

Used in 1940s+ as first modern pesticide (opens sodium channels in insect neurons; caused hyperstimulation)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

Problems with DDT?

A

Doesn’t break down
Soluble: can pass through membranes b/c it looks like cholesterol-based hormone
T1/2 is 2-15 years
Accumulates in fatty tissues
Metabolizes to DDE in liver (a reactive metabolite that is more toxic and impairs reproductive enzymes and reduces calcium)
DDT + congeners induce CYTP450 (oxidative stress)
Biomagnifies 10 mill-fold (trophic birds are high risk)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

Benefits of DDT?

A

Used in WWII: the first war more people died from trauma than disease
Against malaria: dec from 1 mill cases to 9 in Taiwan over 24 years

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

What is biomagnification?

A

The increase of chemical concentrations through the foodchain

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

What is bioaccumulation?

A

The accumulation of a chemical concentration in ONE individual over their lifespan
From ALL external sources and ALL internal processes

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

What is the importance of “Silent Spring”?

A

Realization that humans alter the ecosystem and have long-term consequences through “invisible” technology
- Look at DDT, Agent Orange,, and Love Canal

Caused a policy change through a congressional hearing initiated by Kennedy

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

What does the general population use that affect pollution?

A

Disposing meds (most are tossed or flushed: 89.4%)
Organic wastewater contaminants (common are coprostanol, cholesterol, and caffeine)
PPCPs (pharmaceuticals & personal care products)
Endocrine disruptors (ex. artificial hormones) (highest concentration was detergent metabolites, then steroids and plasticizers)
Antibiotics
*These all are ‘pseudo’-persistent

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

What is ‘pseudo’-persistence?

A

chemicals that might break down easily, but are used on a daily basis so never leave the environment

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

What is a contaminant?

A

A substance that is present in greater than natural concentrations as a result of human activity

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

What is ecotoxicology?

A

(ecology + toxicology)
Definitions change over time; but are generally the same:
- Toxicology branch concerned with study of toxic effects, caused by natural & synthetic pollutants, to the constituents of the ecosystem (animals, vegetable, microbial)
- The study of poisons on individual organisms, to the ecological effects of pollutants

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

What is a pollutant?

A

A substance that occurs in the environment at least in part of human activity and which has a deleterious effect on living organisms

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
What is xenobiotic?
A foreign chemical not produced in nature and not considered a constitutive component of a biological system
26
What are the SCALES of an interdisciplinary field?
Molecules to ecosystems Complexity of hierarchical scales Learning adverse outcome pathways (toxicant to population response)
27
What are the SPECIALTIES of an interdisciplinary field?
Complexities of different specialities (different fields working together to determine outcomes)
28
List the organic legacy pollutants...
PAHs (Polycyclic aromatic hydrocarbons) PCBs (polychlorinated biphenyls) POP (Persistent organic pollutants) "dirty dozen" Organophosphate insecticides
29
What are organic pollutants?
Contain carbon and at least 1 C-H covalent bond Behavior dependent on the structure Source is natural or anthropogenic
30
What are the characteristics of the C-H covalent bond?
Low polarity | Low water solubility
31
What are the basic characteristics of PAHs?
2+ fused benzene rings Persistent (years -> decades) Natural and anthropogenic (most common) Have pyrolysis reactions (decomposes at high temps w/out O2)
32
Examples of natural sources of PAHs...
Volcanos Fires Natural oil seep
33
Examples of anthropogenic sources of PAHs...
Industry generators Internal combustion engines Grills Offshore oil platforms
34
What happens to PAHs as their molecular weight increases?
``` Dec. volatilization Inc. bioaccumulation Inc. absorption to particles Dec. solubility (inc. Kow) Inc. environmental persistence ```
35
What happens to PAHs released on land?
Evaporate | Penetrate soil -> metabolized by plants/soil invertebrates
36
What happens to PAHs released in water?
Evaporate Float Degradation by microbes Metabolized by algae/zooplankton/fish...
37
How do PAHs affect thermoregulation of birds?
?
38
What are the ecotoxicological effects of PAHs?
Physical: smothering, reduced light Habitat change: alter pH, dec. O2, dec. food availability Toxicity: cellular membranes and enzyme-bound membranes
39
What are the properties of PCBs?
``` Low water solubility (high in solvents & fats) Low vapor pressure High dielectric constant High flashpoint High thermal conductivity Inert ```
40
What are the industrial uses of PCBs?
Used in transformers and capacitors | A coolant, lubricant, PVC in electrical wires, caulking sealant, and wood floor polish
41
How are PCBs different from PAHs?
PCBs are chlorinated | - It adds a charge to the chemical
42
How does chlorine affect PCBs?
More chlorine = more oily | Percentage of chlorine changes the properties
43
What happens to PCBs in the environment?
Persistent: resist breakdown (can take a century) and cycle between air, water, & soil Transportable: absorb to particles so carried long distances (lighter compounds move further) Accumulate: move up food chains in fatty tissues (a PBT)
44
What is a PBT?
A Persistent Bioaccumulant Toxin
45
List the characteristics of POPs...
Persist in environment Bioaccumulate through food web Pose risk of causing adverse effects to human health & environment
46
What happened to the "dirty dozen"?
They were banned 12 POPs that were deemed unsafe Ex. DDT
47
What are organophosphate insecticides?
Initially developed as nerve gas agents Inhibit acetylcholinesterase activity -> blocks acetylcholine metabolism - Causes muscular rigidity & paralysis in insects High water solubility Low soil persistence T1/2 = days to week (however, consistent use)
48
Why are metals ubiquitous (everywhere)?
Because they are used in countless industries, commercial and consumer products * They are the most common ubiquitous chemicals
49
What is a unique property of metals?
They are elemental: they do NOT breakdown
50
How would you treat acute metal toxicity?
``` Using chelators (compounds that form complexes with metal ions) Useless with chronic toxicity ```
51
What is a problem with chelators?
Can bind to the wrong thing: there are many useful metals in the body that might be taken instead
52
What are toxic mechanisms of metals?
Promoter of oxidation Competition for divalent cation binding sites Binding of sulfhydryl groups
53
What are the sources of arsenic?
Industrial: from use in wood preservation & in microelectronics industry Human environment: from fallout of smelters and arsenic pesticide spraying Natural: Deep-water well water ingestion
54
What are key exposure routes of pollutants?
Ingestion Inhalation Dermal contact
55
What is the percentage of natural mercury sources? What are they from?
30-40% | Soil, ocean, geogenic, evapotranspiration, recycling
56
What is mercury most used for?
``` Small-scale gold mining (30%) Chlor-Alkali (21%) Batteries (18%) Dental amalgam: cavity caps (8%) Catalyst for vinyl chloride monomer... (8%) ```
57
What is the cycle of mercury from coal burning to the environment?
Hg-S in coal -> releases Hg^0 as vapor when burned -> lasts up to a year in atmosphere as Hg^0 -> oxidizes to Hg^2+ -> drops to ground -> converts to MeHg via sulfate reducing bacteria (SRB) -> Biomagnifies
58
What does methylmercury do to the body (MeHg)?
A neurodevelopment threat (especially in pregnant women) - Crosses membranes (including blood brain barrier & placenta) - High affinity for protein thiols (multiple targets) Bioaccumulates in muscles
59
What is the movement of the neurotoxicity of MeHg due to continued exposure?
Molecular & neurochemical disruption -> | Sub-clinical neurophysiological impacts -> overt neurotoxicity & clinical "Minimata" disease
60
What is the "Minimata" disease?
Minimata was the name of a Japanese town exposed to chemicals from a plant Caused disease form MeHg
61
What is a point source?
Any single identifiable source of pollution from which pollutants are discharged
62
What is the NPRI?
National pollutant release inventory Canada's inventory of pollutant releases, disposals, and transfers Has over 320 pollutants from over 7,000 facilities
63
What is a non-point source?
Pollutants from diffuse sources | This is mainly due to precipitation
64
How does the polarity affect pollutants?
Determines if they are water soluble | More negative = more water soluble
65
What is the Kow?
Concentration in octanol/concentration in water
66
What happens if there is a high Kow?
Hydrophobic (water-resistant) | Lipophilic (fat-soluble)
67
What happens if there is a low Kow?
Hydrophilic (water-soluble) | Lipophobic (fat-resistant)
68
When does the vapor pressure decrease?
With inc. weight
69
What is fugacity?
The combination of the polarity, Kow, and vapor pressure to determine: - escaping tendency from compartment - establish equilibrium in chemicals between environmental phases
70
What is the biota?
Air, soil, and water
71
What is exposure?
Any condition which provides an opportunity for an external environment agent to contact human body Magnitude x frequency x duration
72
What is exposure assessment?
Measure or estimate the intensity, frequency, or duration of human exposure to an agent
73
Dose-response assessment?
Characterize relationship between varying exposures and incidences of adverse effects in exposed populations
74
What is PPM?
part per million
75
What is PPB?
part per billion
76
Bioconcentration is...
Net accumulation of a contaminant in an organisms from water ONLY
77
What are the key components of bioaccumulation?
Uptake Biotransform Eliminate
78
What is biotransformation?
Biologically mediated transformation of a chemical compound to another Involves enzymes Leads to inc. elimination
79
How does biotransformation occur in metals?
Organic conversion by microbes Sequestration by metallothioneins Biomineralization
80
How does biotransformation occur in organic chemicals?
Add polarity to more easily leave body (water soluble) | Conjugate polar chemicals
81
What are the types of elimination of chemicals from the body?
Excretion: physical process Biotransformation: chemical process Depuration: contaminated organism placed in clean environment (loss of contaminant over time)
82
How does the liver help with excretion?
Deals with organics mostly | Deals with large compounds
83
How does the kidney help with excretion?
Deals with metals mostly | Deals with smaller compounds
84
What is toxicology?
Study of adverse effects of chemicals on living organisms
85
What is a dose response curve?
Describes how response to a toxicant changes with the dose | Supports causality between exposure and effect
86
What are the assumptions of the dose response curve?
Response is due to the chemical Magnitude of response due to the dose Quantifiable method used to assess response
87
What are biomarkers?
- Biological response to a chemical that gives a measure of exposure & toxic effect - Alterations in cellular or biochemical components, or processes, structure, or functions that is measurable in a biological system or sample
88
What biomarkers are used to study PAHs
DNA adducts (chemical covalently binds to DNA) COMET assay Phase 1 or 2 biomarkers CYP1a/EROD
89
Genotoxicity is...
When chemicals effect DNA | Cause DNA adducts
90
What does a Comet assay do?
Measures DNA strand breaks in cells
91
What are oxidative stress biomarkers?
Enzymes turned on when chemicals are polarized. There are reactive byproducts that attack DNA or oxidize lipids
92
What does CYP1a do?
Chemical binds in cell that is taken to nucleus. Enzymes are turned on to attack chemical CYP1a is a marker via EROD Assay to test if chemical is in nucleus.
93
What do scientists care most about with pollution?
Growth Reproduction Survival
94
What are endocrine disrupting chemicals (EDCs)?
Exogenous substance or mixture that alter functions of the endocrine system and consequently cause adverse health effects in an intact organisms, its progeny, or the population
95
What can EDCs do to cells?
Mimic natural hormones by binding to their receptors | Alter recognition, biosynthesis, storage, release, transport, and clearance of hormones
96
What do EDCs do to the body?
``` Decline sperm quality Impari fertility Inc. spontaneous abortions Decline sex ratios (less men) Endometriosis Early puberty Neurobehavioral disorders Pop. decline ```
97
What is the endocrine system?
Collection of ductless tubes | Synthesize and secrete hormones
98
How much EDCs are needed to cause effects?
About ppb
99
Why would whole lakes be used as experiments?
Need ecosystems to show compelling evidence of changes in the environment due to pollution (such as acid rain, mercury, eutrophication...) Biggest: 58 pristine lakes set aside in 1968 (was shut down for a time due to budget, but reopened by scientists as a non-profit)
100
What is tiered testing?
Level 1: sorting & prioritization based upon existing info Level 2: In vitro assays providing mechanistic data Level 3: In vivo assay providing data about single endocrine mechanisms and effects Level 4: in vivo assay providing data about multiple endocrine mechanisms and effects Level 5: in vivo assays providing data on effects from endocrine and other mechanisms
101
What is the adverse outcome pathway?
Showing step by step (concept model) the toxicant from making to outcomes
102
What is the general adaptation syndrome (GAS)?
Non-specific changes constituting the body's attempt to reestablish or maintain homeostasis while under the influence of a stressor. Hormones are released to get body to fight, but deplete after time. Ex. getting sick when continually stressed
103
What does the GAS have to do with pollutants?
The cortisol stress response can be impaired due to chemicals such as PAHs, PCBs, mercury, etc. Can't mount response b/c hormones deplete over time
104
What is behavioral ecotoxicology?
Interaction of organisms with its external environment
105
What are challenges of behavioral ecotoxicology?
Latency period Inter species sensitivity Are behavioral changes due to ecology or toxicology? Not easy to monitor in nature Is there any tolerance, resistance, or adaptation?
106
What is commonly measured in behavioral ecotoxicology?
Avoidance (change in response to stimulus) Activity level Feeding Performance

Pollution & Bioremediation (2 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2025 Bold Learning Solutions. Terms and Conditions