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Pollution Principles and Processes TREN 1F90: Sustainability, Environment and Tourism.

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Presentation on theme: "Pollution Principles and Processes TREN 1F90: Sustainability, Environment and Tourism."— Presentation transcript:

1 Pollution Principles and Processes TREN 1F90: Sustainability, Environment and Tourism

2 Note worksheet Available for download at tren1f90/2006/Pollution Principles and Processes.pdf tren1f90/2006/Pollution Principles and Processes.pdf

3 Environmental Pollution Any physical, chemical, or biological alteration of air, water, or land that is harmful to living organisms

4 Two main groups of pollutants

5 ____________ or _______ ______: pollutants which are harmful in almost any amount

6 Two main groups of pollutants Nonthreshold or Gradual Agents: pollutants which are harmful in almost any amount

7 Two main groups of pollutants Nonthreshold or Gradual Agents: pollutants which are harmful in almost any amount _________ ______: pollutants which have a harmful effect only above a certain threshold level

8 Two main groups of pollutants Nonthreshold or Gradual Agents: pollutants which are harmful in almost any amount Threshold agents: pollutants which have a harmful effect only above a certain threshold level

9 DOSE / RESPONSE CURVES Illustrate the effects of toxic substances on living organisms

10 Image credit: aquaticpath.umd.edu/.../ module1- factors.htmlaquaticpath.umd.edu/.../ module1- factors.html DOSE / RESPONSE CURVES Illustrate the effects of toxic substances on living organisms Response = detectable effect on organism Dose = amount of substance encountered

11 Nonthreshold (Gradual) Agent DOSEDOSE DOSE (ppm) RESPONSE Any level of aflatoxin (dose) will increase the lifetime probability of liver tumors in rats (response)

12 Threshold agent DOSE (% in diet) RESPONSE The lifetime probability of bladder tumors in rats increases once a 3% threshold in diet is crossed

13 Types of pollutants Persistent Do not degrade in the environment

14 Types of pollutants Persistent Do not degrade in the environment Non – persistent Break down in the environment (biodegradable / photodegradable / chemodegradable)

15 Forms of BIOACCUMULATION Bioconcentration Accumulation of substances (toxic or not) in the living tissues of an organism (e.g., iodine in thyroid gland of humans) Thyroid produces hormones (e.g., thyroxine (T4) and triiodothyronine (T3) which regulate metabolism of many systems in the body Iodine is an essential component of T3 and T4.

16 Iodine deficiency results in goiter (enlarged thyroid)

17 Not just a developing-nation syndrome: US ‘goiter belt’ at turn of last century Controlled by introducing iodized salt in 1924

18 Forms of BIOACCUMULATION Biomagnification Buildup of substances in organisms across successive trophic levels

19

20 Forms of BIOACCUMULATION Biomagnification Buildup of substances in organisms across successive trophic levels 1° PRODUCERS1° CONSUMERS 2° CONSUMERS 3° CONSUMERS 4° CONSUMERS 4°- 5° CONSUMERS

21 Forms of BIOACCUMULATION Biomagnification Buildup of substances in organisms across successive trophic levels Reasons: –trophic pyramid interactions –water insolubility / lipophilic action of many biomagnifiable substances –slow biodegradability of substances –biological novelty of synthetic substances: no naturally occurring counterparts ==> no natural elimination mechanism

22 Effects of Pollutants Miller (1990) classifies the effects of pollutants into five (nonexclusive) categories in order of increasing seriousness to humans: 1._____________________________________________ 2._____________________________________________ 3._____________________________________________ 4._____________________________________________ 5._____________________________________________ The above classification system may be further subdivided to include more detailed biological responses at the organism, population, or community ecosystem levels.

23 Effects of Pollutants Miller (1990) classifies the effects of pollutants into five (nonexclusive) categories in order of increasing seriousness to humans: 1.Nuisance / Aesthetic Insult 2._____________________________________________ 3._____________________________________________ 4._____________________________________________ 5._____________________________________________ The above classification system may be further subdivided to include more detailed biological responses at the organism, population, or community ecosystem levels.

24 Effects of Pollutants Miller (1990) classifies the effects of pollutants into five (nonexclusive) categories in order of increasing seriousness to humans: 1.Nuisance / Aesthetic Insult 2.Property Damage 3._____________________________________________ 4._____________________________________________ 5._____________________________________________ The above classification system may be further subdivided to include more detailed biological responses at the organism, population, or community ecosystem levels.

25 Effects of Pollutants Miller (1990) classifies the effects of pollutants into five (nonexclusive) categories in order of increasing seriousness to humans: 1.Nuisance / Aesthetic Insult 2.Property Damage 3.Damage to Plant and Non-human Life 4._____________________________________________ 5._____________________________________________ The above classification system may be further subdivided to include more detailed biological responses at the organism, population, or community ecosystem levels.

26 Effects of Pollutants Miller (1990) classifies the effects of pollutants into five (nonexclusive) categories in order of increasing seriousness to humans: 1.Nuisance / Aesthetic Insult 2.Property Damage 3.Damage to Plant and Non-human Life 4.Damage to Human Health 5._____________________________________________ The above classification system may be further subdivided to include more detailed biological responses at the organism, population, or community ecosystem levels.

27 Effects of Pollutants Miller (1990) classifies the effects of pollutants into five (nonexclusive) categories in order of increasing seriousness to humans: 1.Nuisance / Aesthetic Insult 2.Property Damage 3.Damage to Plant and Non-human Life 4.Damage to Human Health 5.Disruption of Ecosystems The above classification system may be further subdivided to include more detailed biological responses at the organism, population, or community ecosystem levels.

28 Toxicology

29 Toxin: A chemical substance which adversely affects living organisms Image credit: /m-dna phpwww.eurekalert.org/.../ /m-dna php

30 Effects of Toxins Acute effects: symptoms which appear immediately after exposure to the toxin. Usually caused by fairly high concentrations of toxins during short ‑ term exposures. Chronic effects: delayed but long ‑ lasting responses to toxic agents. Generally the result of low ‑ level exposure over long periods. Often difficult to diagnose, predict, and detect.

31 Image credit: greenbook/nersc3/node28.htm l greenbook/nersc3/node28.htm l Carcinogen: a cancer-causing agent E.g., polycyclic aromatic hydrocarbons and amines (present in automobile exhaust, tobacco smoke, dyes, and barbecued meat and fish)

32 Image credit: greenbook/nersc3/node28.htm l greenbook/nersc3/node28.htm l Carcinogen: Cancer is initiated in the cell by attacking the DNA bases (A, G, C, T) Once bound to the bases, they can alter the DNA shape (conformation). This change can profoundly impact on the normal functioning of DNA during replication.

33 Image credit: immuno_metastisis.htmwww.gcarlson.com/ immuno_metastisis.htm Metastasis: The migration / spread of cancer cells in the body

34 Image credit: Teratogen: Agent which causes birth defects

35 Image credit: engl_or/or18802.jpg Teratogen: Agent which causes birth defects e.g. alcohol (fetal alcohol syndrome)

36 Image credit: teratology.org/jfs/ ThalidomidePics.htmlteratology.org/jfs/ ThalidomidePics.html Teratogen: Agent which causes birth defects e.g. thalidomide

37 Image credit: April01/Colvin.htmlwww.llnl.gov/str/ April01/Colvin.html Mutagen: agent which causes genetic mutation e.g. radiation, certain foods and chemicals, some viruses

38 Gene / point mutation: Alteration to the DNA base sequence Clastogenesis: Chromosomal breaks; gain, loss, or rearrangement of pieces of chromosomes Aneuploidy / Polyploidy: Uneven separation of chromosomes during cell division, or addition of entire chromosomes Three main types of genetic alteration:

39 Gene / point mutation: Alteration to the DNA base sequence Clastogenesis: Chromosomal breaks; gain, loss, or rearrangement of pieces of chromosomes Aneuploidy / Polyploidy: e.g., Down syndrome (Trisomy 21) Three main types of genetic alteration:

40 Image credit: sci.cancerresearchuk.org/.../cap/capanal.html sci.cancerresearchuk.org/.../cap/capanal.html Capping enzyme for mRNA (red) and reaction products Modes of action of toxins 1.disturbance of enzymatic activity to alter the functioning of a cell, tissue or organ Enzyme: A protein that initiates or accelerates the rate of chemical reactions. Enzymes are catalysts that promote reactions repeatedly, without being damaged by the reactions. The three-dimensional structure and composition of enzymes is critical to their effectiveness.

41 Image credit: chempics/Enzymes.html chempics/Enzymes.html Modes of action of toxins 1.disturbance of enzymatic activity to alter the functioning of a cell, tissue or organ

42 Image credit: chempics/Enzymes.html chempics/Enzymes.html Modes of action of toxins 1.disturbance of enzymatic activity to alter the functioning of a cell, tissue or organ

43 Modes of action of toxins 1.disturbance of enzymatic activity to alter the functioning of a cell, tissue or organ Examples: Mercury: binds with sulfhydryl and thiol groups found in most proteins and all enzymes, and interferes with normal fetal development → Minamata disease

44 Modes of action of toxins 1.disturbance of enzymatic activity to alter the functioning of a cell, tissue or organ Examples: Arsenic: induces skin lesions, neurological disorders, and chromosomal abnormalities leading to cancer Image credit: doc.asp?cat=850&doc =563 doc.asp?cat=850&doc =563 Skin lesions from arsenic in water supply - Bangladesh

45 Modes of action of toxins 2.Direct binding to cells or molecules within the cell, upsetting cellular metabolism

46 Image credit: dept.physics.upen n.edu/.../ subsection1_1_3. html dept.physics.upen n.edu/.../ subsection1_1_3. html Modes of action of toxins 2.Direct binding to cells or molecules within the cell, upsetting cellular metabolism Example: Carbon monoxide: binds to hemoglobin in blood → disrupts oxygen and carbon dioxide transport Hemoglobin molecule with carbon monoxide attached

47 Image copyright 2000 by Nucleus Communications, Inc. All rights reserved. See “Why is Carbon Monoxide so Poisonous?” at carbon_monoxide.htm carbon_monoxide.htm

48 Modes of action of toxins 3.stimulate release of other naturally occurring cell substances that have an adverse effect when present in excess

49 Image credit: du/ medsci520/cell_inju ry.htm du/ medsci520/cell_inju ry.htm Modes of action of toxins 3.stimulate release of other naturally occurring cell substances that have an adverse effect when present in excess Example: Carbon tetrachloride: stimulates production of adrenalin → overproduction results in liver damage Centrilobular hepatic necrosis and fatty change in a patient poisoned by carbon tetrachloride

50 Factors affecting toxicity of chemicals 1.Dose and duration of exposure 2.Biological reactivity: how it reacts with enzymes and other cellular components. Inert substances are generally non toxic, with a few exceptions (e.g.silica dust, asbestos fibres)

51 Factors affecting toxicity of chemicals 3.Age: young, growing organisms generally more susceptible to toxins than are mature adults. Examples: lead and mercury poisoning have severe effects on developing nervous systems) 4.Health Status: poor nutrition, stress, and diseases make individuals more susceptible to the effects of toxins

52 Factors affecting toxicity of chemicals 5.Synergism: different chemical substances may act together so that the toxic effect of the combination is greater than the simple sum of the two individual responses e.g. alcohol and barbiturates: neither taken alone in small amounts is dangerous, but combination can be deadly ==> synergistic effect.

53 Factors affecting toxicity of chemicals 6.Antagonism: different chemical substances may act together so that the toxic effect of the combination is less than what would be predicted from the individual toxicities e.g., selenium reduces the toxic effects of organomercury compounds)

54 Factors affecting toxicity of chemicals 7.Mode of exposure: Percutaneous: skin Respiratory: nose, pharynx, trachea, bronchii, lungs Oral: mouth, esophagus, stomach, intestines


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