Chapter 15: Environmental Health, Pollution and Toxicology

1. Chapter 15: Environmental Health, Pollution and Toxicology

2. Disease is often due to an imbalance resulting from poor adjustment between the individual and the environment. • Continuum from state of health to disease • Gray zone in-between • As a result of exposure to chemicals in the environment we may be in the midst of an epidemic of chronic disease. Disease

3. Seldom has a one-cause-one-effect relationship w/ the environment • Depends on several factors • Physical environment • Biological environment • Lifestyle Disease

4. Chances of experiencing serious environmental health problems and disease depends on • The water we drink • The air we breathe • The soil we grow crops in • The rocks we build our homes on Disease

5. Natural processes can release harmful materials into the soil, water or air. • Lake Nyos in Cameroon, Africa • Experienced sudden release of carbon dioxide • Killed 1,800 people in near by town. Disease

8. Lake Nyos Webquest Questions • Where is Lake Nyos located? • In what chain of volcanos is Lake Nyos situated? • Describe the Lake Nyos Disaster • Are there any other lakes where this could or has happened? • On the first link below, it is stated that the amount of gas that can be dissolved in the water is dependent on what two things? What law tells us that this is true? • Air is typically comprised of what percent carbon dioxide? What concentration level is considered fatal? • What is being done to avert similar disasters in the future? Describe the solution.

9. Polluted environment • impure, dirty, or otherwise unclean. • Pollution refers to the occurrence of unwanted change in the environment • introduction of harmful materials or the production of harmful conditions. • Contamination • similar to that of pollution • implies making something unfit for a particular use through the introduction of undesirable materials • Think of contamination as rendering something polluted. Terminology

10. Toxic refers to materials (pollutants) that are poisonous to people and other living things. • Toxicology is the science that studies chemicals that are known to be or could be toxic. • Carcinogen is a particular kind of toxin that increases the risk of cancer. • Carcinogens are the most feared and regulated toxins in our society. Terminology

11. Additivity - A biologic response to exposure to multiple substances that equals the sum of responses of all the individual substances added together • Antagonism – A biologic response to exposure to multiple substances that is less than would be expected if the known effects of the individual substances were added together • Synergism • The interaction of different substances resulting in a total effect great than the sum of the effects of the separate substances. • E.g. sulfur dioxide and coal dust Terminology

12. Pollutants may be introduced into the environment at: • Point sources, such as smokestacks, pipes discharging into waterways, stream entering the ocean, or accidental spills. • The Clean Water Act specifically defines a "point source" in section 502(14) of the Act. That definition states: Terminology

13. The term "point source" means any discernible, confined and discrete conveyance, including but not limited to any pipe, ditch, channel, tunnel, conduit, well, discrete fissure, container, rolling stock, concentrated animal feeding operation, or vessel or other floating craft, from which pollutants are or may be discharged. This term does not include agricultural storm water discharges and return flows from irrigated agriculture. Terminology

14. Pollutants may also be introduced into the environment at: • Non point sources (Area sources), which are more diffused over the land and include urban and agricultural runoff and, or • mobile sources such as automobile exhaust. Terminology

15. Nonpoint source (NPS) pollution, unlike pollution from industrial and sewage treatment plants, comes from many diffuse sources. NPS pollution is caused by rainfall or snowmelt moving over and through the ground. As the runoff moves, it picks up and carries away natural and human-made pollutants, finally depositing them into lakes, rivers, wetlands, coastal waters, and even our underground sources of drinking water. Nonpoint Source Pollution

16. Nonpoint sources include: • Excess fertilizers, herbicides, and insecticides from agricultural lands and residential areas; • Oil, grease, and toxic chemicals from urban runoff and energy production; • Sediment from improperly managed construction sites, crop and forest lands, and eroding streambanks; • Salt from irrigation practices and acid drainage from abandoned mines; • Bacteria and nutrients from livestock, pet wastes, and faulty septic systems; • Atmospheric deposition and hydromodification are also sources of nonpoint source pollution. Nonpoint Source Pollution

17. Point Source or Nonpoint Source? Why?

18. How the amount or concentration of a particular pollutant or toxin present in the environment is reported varies widely. • waste water pollution reported in millions of gallons • Emissions of nitrogen oxides reported in tons per year • Others given by a volume, mass or weight • Ppm (parts per million), ppb parts per billion), mg/kg or % Measuring the Amount of Pollution

19. Suppose 17 grams of sucrose is dissolved in 183 grams of water. What is the concentration of sucrose in ppm? (17 / 200) x 1,000,000 = 85,000 ppm The solubility of AgCl is 0.008 grams/100 grams of water. What is this concentration in ppm? Practice 0.008 X 1000000 = 80 ppm 100

20. Infectious disease • Spread from the interactions between individuals and food, water, air or soil. • Can travel globally via airplanes • New diseases emerging and previous ones reemerging • Diseases that can be controlled by manipulating the environment • classified as environmental health concerns Infectious Agents

21. Legionellosis • Occurs where air-conditioning systems have been contaminated by disease-causing organisms. • Giardiasis • a protozoan infection of the small intestine spread via food, water, or person-to-person contact. • Salmonella • a food-poisoning bacterial infection spread via water or food. Environmentally Transmitted Infectious Diseases

22. Malaria • a protozoan infection transmitted by mosquitoes. • Lyme disease • Transmitted by ticks. • Cryptosporidosis • a protozoan infection transmitted via water or person-to-person contact. • Anthrax • Bacterial infection spread by terrorist activity. Environmentally Transmitted Infectious Diseases

23. The major heavy metals that pose health hazards to people and ecosystems include: • mercury, lead, cadmium, nickel, gold, platinum, silver, bismuth, arsenic, selenium, vanadium, chromium, and thallium. • Each may be found in soil and water not contaminated by humans. • Often have direct physiological effects. • Stored and incorporated in living tissue • Fatty body tissue • Content in our bodies referred to as body burden. Toxic Heavy Metals

24. Chemical elements can become concentrated • Biomagnification- - the increased concentration of a toxic chemical the higher an animal is on the food chain. • Bioaccumulation- • the accumulation or increase in concentration of a substance in living tissue of a particular organism. • E.g. Cadmium, mercury Toxic Pathways

26. Located on the coast of the Yatsushiro Sea in southwestern Japan. • The village was very poor. • Mostly fishermen and farmers. • Villagers welcome Chisso Corporation in 1907 The Town of Minamata http://www.jnto.go.jp/tourism/img/map/86.gif

27. Chisso = nitrogen • Produced fertilizer • 1907: Chisso Corp. builds a fertilizer plant in the Minamata. • Job openings • 1925: plant begins dumping untreated wastewater into Minamata Bay • Kills fish • Fisherman Payoffs Chisso Corporation http://www.japanfocus.org/images/592-3.jpg

28. 1932: Chisso plant begins to produce acetaldehyde to be used in the production of plastic, perfume and drugs. • Acetaldehyde is made from acetylene and water with a mercury catalyst. • After WWII plastic production boomed and Chisso Corp. grew. • By 1970: Chisso brought Japan 60% of its income and owned nearly 70% of the land in Minamata. Chisso Corporation http://www-personal.umich.edu/~tobin/Smith2.jpg

29. Early 1950’s: • Dead fish wash ashore • Crows fall out of sky • Suicidal dancing cats • Mercury moves up the food chain. Bizarre Behavior in Animals http://flickr.com/photos/tropicalrips/127535537/

30. Behaviors witnessed: • Loss of motor control in hands • Violent tremors • Swaggered walk • Insanity • They called it the “Cat-dancing” disease • Nobody knew the cause of the epidemic. • Many hid for fear of ridicule Mid 1950’s: Behavior Seen in Humans http://www.hamline.edu/personal/amurphy01/es110/eswebsite/ProjectsSpring03/ebarker/Minamata%20Web%20Page.htm

31. 1956: Epidemiological and medical researchers at Chisso Corp. Hospital begin researching the cause of the epidemic • They determine that the disease is from mercury poisoning by consuming the contaminated fish and shellfish of Minamata Bay. • In 1959 Dr. Hosokawa performs tests on cats at the hospital and has direct evidence that the acetaldehyde waste water is to blame for the disease • Chisso corp. forbids Dr. Hosokawa from conducting any further experiments and redirects the flow of wastewater from the bay to the river to avoid being caught. • A larger geographical area contaminated. • Children born with horrifying deformities. Putting the Pieces Together

32. Putting the Pieces Together http://www.nimd.go.jp/archives/english/tenji/a_corner/image/hasseimap.gif

33. 1968: Government ran Public Health service traces the contamination to the MinamataChisso plant. • Government halts the production of acetaldehyde • 1972: Government publically announces Chisso Corp’s part in the Minamata epidemic and orders Chisso Corp to pay compensation to the families that were affected. http://www.icett.or.jp/lpca_jp.nsf/505b1fe895fd2a8c492567ca000d587d/e35dc782654b21d7492567ca000d8c50?OpenDocument

34. Centers for Disease Control and Prevention

35. 30-70 tons of methyl mercury was dumped into the Bay • 10,000 people affected by Minamata disease. • 3,000 died • Compensation has been given to families as recently as 1990. • Highest compensation for the disaster was just under $3,000. The Aftermath http://www.physorg.com/news110359851.html

36. Methylmercury exposure in humans is from consumption of fish, marine mammals, and crustaceans • 95% of fish-derived methylmercury is absorbed into the gastrointestinal tract and distributed throughout the body • Highest in concentration in hair Methylmercury :In the Body www.mercury.utah.gov/images/health_effects.jpg

37. Minamata Disease in the Nervous System Areas in red show areas typically affected by the presence of methylmercury in the system . The lesions show characteristic signs and symptoms in Minamata disease. 1. Gait disturbance, loss of balance (ataxia), speech disturbance (Dysarthria) 2. Sight disturbance of peripheral areas in the visual fields (constriction of visual fields) 3. Stereo anesthesia (Disturbance of sensation) 4. Muscle weakness, muscle cramp (disturbance of movement) 5. Hardness of hearing (hearing disturbance) 6. Disturbance of sense of pain, touch or temperature (Disturbance of sensation) National institute of Minamata Disease Archives

38. Symptoms of the Disease W. Eugene SmithTomoko Uemura in Her BathMinamata, 1972 • Mild • Ataxia • Muscle weakness • Narrowed field of vision • Hearing and speech damage • Severe cases cause • Insanity • Paralysis • Coma • Death

39. More Symptoms • A significant effect of Minamata is the onset of symptoms similar to those of cerebral palsy • Fetal Minamata Disease • A pregnant mother ingests toxic fish and the methylmercuryconcetrates inside the placenta. • Harms the fetus while the mother is relatively unaffected http://picasaweb.google.com/jazzyv0504/SAKURA#5065603192708172658

40. These are all children with congenital (fetal) Minamata Disease due to intrauterine methyl mercury poisoning (Harda 1986).

41. Mercury (Hg) is the only metal that is liquid at room temperature. It melts at -38.9oC and boils at 356.6oC. • Mercury conducts electricity, expands uniformly with temperature and easily forms alloys with other metals (called amalgams). • For these reasons, it is used in many products found in homes and schools. Mercury: The Basics

42. Mercury exists in three oxidation states: • Hg0 (elemental mercury). • Hg22+ (mercurous). • Hg2+ (mercuric). • Mercurous and mercuric form numerous inorganic and organic chemical compounds. • Organic forms of mercury, especially methyl mercury, CH3Hg(II)X, where “X” is a ligand (typically Cl- or OH-) are the most toxic forms. Mercury Chemistry

43. We use its unique properties to conduct electricity, measure temperature and pressure, act as a biocide, preservative and disinfectant and catalyze reactions. • It is the use of mercury in catalysis that contributed to the events in Minamata. • Other uses include batteries, pesticides, fungicides, dyes and pigments, and the scientific apparati. Uses of Mercury

44. Upwards of 70% of the mercury in the environment comes from anthropogenic sources, including: • Metal processing, waste incineration, and coal-powered plants. • Natural sources include volcanoes, natural mercury deposits, and volatilization from the ocean. • Estimates are that human sources have nearly doubled or tripled the amount of mercury in the atmosphere. Mercury in the Environment

46. The Aquatic Mercury Cycle

47. In soil, mercury is relatively harmless in its elemental, divalent or particulate forms. It is only when Hg2+ is converted to methylmercury (CH3Hg+) that it becomes a hazard. • Methylmercury is produced as a byproduct of the metabolic processes of sulfate reducing bacteria in anaerobic environments. • In the environment, sulfate-reducing bacteria take up mercury in its inorganic form and through metabolic processes convert it to methylmercury. Sulfate-reducing bacteria are found in anaerobic conditions, typical of the well-buried muddy sediments of rivers, lakes, and oceans where methylmercury concentrations tend to be highest. • Sulfate-reducing bacteria use sulfur rather than oxygen as their cellular energy-driving system. One hypothesis is that the uptake of inorganic mercury by sulfate-reducing bacteria occurs via passive diffusion of the dissolved complex HgS. Once the bacterium has taken up this complex, it utilizes detoxification enzymes to strip the sulfur group from the complex and replaces it with a methyl group: HgS → CH3Hg(II)X + H

49. The Minamata Spill • Dredging • Other ways of cleaning mercury spill Mercury-resistant bacteria, developed by researchers from Inter American University of Puerto Rico, Bayamon Campus, contained either the mouse gene for metallothionein or the bacterial gene for polyphosphate kinase. Both strains of bacteria were able to grow in very high concentrations (120µM) of mercury, and when the bacteria containing metallothionein were grown in a solution containing 24 times the dose of mercury which would kill non-resistant bacteria, they were able to remove more than 80% of it from the solution in five days. Cleaning up

50. What’s is Dredging? – the process of removing sediment for the bottom of bodies of water. • Underwater excavation Minamata Cleanup