Environmental Health Final Baylor ENV 3314

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Endocrine disrupting chemicals

"Environmental estrogens" or "androgens" • Substances that affect the reproductive hormone systems • Dieldrin, lindane, endosulfan - bind to estrogen receptor • May act as cancer promoters by having an influence on the onset of female cancers that are thought to be caused by estrogenic activity Some substances can cause the collapse of fish communities • DDT reduced egg‐shell thickness in birds reduced reproductive success • In humans, EDC exposures are linked to early onset of puberty, decreased sperm quality, and other effects. • Phthalates, bisphenol A (plastics)

Non‐Ionizing Radiation

"Radiation that has enough energy to move atoms in a molecule around or cause them to vibrate, but not enough to remove electrons" • Sound waves • Visible light • Microwaves • Radio waves • Ultraviolet light

Four food hazard categories

1. Biological 2. Physical (e.g., stone, glass, metal) 3. Chemical 4. Nutritional (presence of nutrients and other food constituents in excessive or deficient amounts that lead to disease)

The Four Stages of Water Treatment in Most Plants

1. Coagulation-removes suspended material 2. Sedimentation-causes heavy particles to settle to bottom of tanks for collection 3. Filtration-removes smaller particles 4. Disinfection-kills bacteria or microorganisms

Factors That Affect Radiation Exposure

1. The total amount of time exposed to the radioactive source 2. Distance from the radioactive source 3. Degree of radioactivity (rate of energy emission) of the radioactive material

Four elements of the water quality based approach:

1. designated uses of the water body (recreation, water supply, aquatic life, agriculture) 2. WQC to protect designated uses (numeric and narrative components) 3. antidegradation policy to maintain and protect existing uses 4. policies addressing implementation issues (low flows, mixing zones)

Polycyclic Aromatic Hydrocarbons

A group of over 100 different chemical that are formed during the incomplete burning of coal, oil and gas, garbage, and other organic substances (tobacco, charbroiled meat, etc.)

Organic solvents

A solvent refers to "a liquid substance capable of dissolving other substances; 'the solvent does not change in forming a solution.'" • Tetrachloroethylene (PCE) • Trichloroethane • Trichloroethylene (TCE) • Toluene • Benzene • Acetone

Hydrocarbons

A substance that consists of only carbon and hydrogen atoms EX: Propane

Methyl Isocyanate (MIC)

An intermediate chemical used in manufacture of carbamate pesticides • Extremely toxic Bhopal, India, 1984: A release of MIC from the Union Carbide plant kills 3,800 people and injures over 500,000

Organophosphates

Anticholinesterase Do not persist in environment No resistance Frequent case of fatal poisonings EX Ant killer Acute effects: impairment of neural impulse transfer (respiratory arrest--> death) Chronic effects: polyneuropathy (numbness, loss of sensory abilities, weakness) Found in: Diazinon, malathion, methyl Examples: Diazinon, malathion, methyl parathion, parathion, chlorpyrifos • Appear in a wide variety of products: sprays, baits, indoor foggers and bombs, flea collars, pet shampoos, powders, animal dips, and granules • Malathion has been approved for direct application to food crops such as fruits (e.g., apples and grapes), row crops, and vegetables (e.g., tomatoes). Cholinergic syndrome: Sweating, salivation, bronchoconstriction, gastrointestinal motility, diarrhea, tremors • Treatment: Atropine (counteract overstimulation of ACh receptors) • Chemical warfare • VX, sarin, tabun, soman Terrorist attack on Toyko subway, 1995

Pesticides

Any substance or mix of substances intended to prevent, destroy, repel, or mitigate pests. Pest can be insects, rodents, weeds, or anything that is in a place it shouldn't be.

Organic Chemicals

Anything that contains carbon atoms Found in all living organisms Ex: Table Sugar (exception: Carbon dioxide is not an organic chemical)

Polychlorinated dioxins and furans

By‐products of certain industrial, non‐industrial, and natural processes (usually combustion) Stable, persistent, bioaccumulative • 7 dioxins and 10 furans are regarded as most important (2,3,7,8 chloro‐substituted) • Group: PCDD/Fs or "dioxins"

Microwaves

Can cause pain without injury

Persistant Organic Pollutants (POPs)

Carbon-containing chemical compounds that, to varying degrees, resists photochemical, biological, and chemical degradation (DDT)

PCBs and health effects

Cause cancer in animals and are designated as probable human carcinogens • May impact the immune system, reproductive system, and children's intellectual development • May limit the development of immune responses to the Epstein‐Barr virus and other viral and bacterial infections

Carbamates

Close relatives of the organophosphate pesticides • Dissipate quickly from the environment as a result of breaking down into other substances • Some are approved for controlling garden pests (e.g., wasps, hornets, and snails). • An ingredient in some products applied to furry pets to control ticks and fleas Examples: • Carbaryl (sevin) • Aldicarb • Propoxur • Metam sodium Metam Sodium Spill: upper Sacramento river

DDT Human Health Effects

Concentrates in the adipose (fatty) tissues of the body. • Lipophilic, bioaccumulative • "Body burden" • Estimated half‐life of approximately 10 years. • All living organisms on earth contain some levels of this pesticide. Linked to: • Cancer (pancreatic, non‐Hodgkin's lymphoma, and breast) • Impaired lactation • Falling sperm counts • Impaired neurologic function (irritability, dizziness, and numbness)

Waterborne Diseases

Conditions that are ". . . transmitted through the ingestion of contaminated water and water acts as the passive carrier of the infectious agent." • Examples are: - Cryptosporidiosis - Cholera - Certain viral infections

Naturally‐Occurring Ionizing Radiation

Cosmic rays • Other forms of radiation that impinge upon earth from outer space • Radiation from geologic formations that contain radioactive elements (radioelements) such as uranium, from which radon gas is formed as a decay product.

Organochlorines

Derived from chlorinated hydrocarbons, which are chemical compounds that contains chlorine, carbon, and hydrogen • Characteristically stable and fat‐soluble; persist in the environment and bioaccumulate in the food chain • Associated with suppression of the immune system and cancer DDT • Lindane • Chlordane • Mirex • Hexachlorobenzene • Methoxychlor

Pyrethrins

Derived from natural sources‐ ‐certain varieties of chrysanthemum flowers • Have great ability to paralyze and kill flying insects • Interfere with transmission of neural impulses via action on sodium channels Generally have low concentrations of the active ingredient • Used inside the home in aerosol cans, insecticide bombs, insecticidal pet shampoos, treatments for lice applied directly to humans, and mosquito repellents • May be inhaled as a result of spraying and may be ingested in foods

Health effects of dioxins?

Duration of exposure • Frequency of exposure • When the exposure occurred • Concentration of the agent • Route of entry into the body Chloracne • Skin rashes • Skin discoloration • Growth of excessive body hair • Liver damage • Possible cancer risks • Endocrine effects • Reproductive and developmental effects

Water Health Advisories

EPA prepares health advisories (HAs) as voluntary exposure guidelines for drinking water contamination. The HAs provide exposure limits for 1-day, 10-day, longer-term, or lifetime exposure periods. They pertain only to non-carcinogenic risks.

Radiation

Energy that moves through space as waves or particles (like visible light). • Particulate radiation: • Alpha, beta, neutron • Wave radiation: • Gamma rays, X‐rays, infrared

Ionizing Radiation

Enough energy to remove electrons from atoms, creating ions. • Sterilizing: irradiated meat • Medical: X‐rays, radiopharmaceuticals • Power generation

Benefits of Hazardous Chemicals

Essential to the functioning of modern society 15,000 chemicals made and used in high volume in the US for manufacturing EVERYTHING

Hepatitis A virus

Foods that are associated commonly with HAV outbreaks include fruits, sandwiches made with cold cuts, dairy products, vegetables, and shellfish. • Common mode for contamination of foods is by HAV‐infected workers in food processing plants and restaurants. • Of the 23,000 cases of hepatitis A reported in the U.S. annually, about 7% are believed to be food‐ or waterborne

Natural Processes and Dioxins

Forest fires and volcanic eruptions • "Natural background" What is the number one source of dioxins in the environment? • Excluding Superfund sites

Drawbacks of Hazardous Chemicals

Human Health Hazards (EX cancer/ birth defects) Rachel Carson's "Silent Spring" brought the dangers of chemicals that were being disseminated into the environment to public attention

Water Quality

I. Economists view water pollution as fund or stock pollutants 1. Fund pollutants are those assimilated by the environment e.g. biodegradable organic chemicals, nutrients, thermal 2. Stock pollutants are those that accumulate in the environment e.g. heavy metals, persistent organic pollutants II. Economic goal in capitalistic system is market efficiency III. Argue that command and control regulatory actions are not efficient

Water Quality Monitoring: Numerical Criteria

I. Scientific assessment of ecological effects caused by a specific pollutant II. Aquatic Life Criteria derived from laboratory bioassay dose responses Criteria Continuous The EPA national water quality criteria recommendation for the highest Concentration (CCC) instream concentration of a toxicant or an effluent to which organisms can be exposed indefinitely without causing unacceptable effects. Criteria Maximum The EPA national water quality criteria recommendation for the highest Concentration (CMC) instream concentration of a toxicant or an effluent to which organisms can be exposed for a brief period of time without causing mortality. III. Bioassays (survival, growth, and reproduction) assess water quality However: 1. Bioassays do not represent the most sensitive species 2. Bioassays do not measure structural and functional responses 3. Bioassays do not measure teratogenicity, carcinogenicity, mutagenicity, or bioaccumulation

Water Quality: Criteria and Standards

I. Section 304(a) of the Clean Water Act requires the EPA to publish and periodically update ambient water quality criteria (WQC). Criteria Recommended and estimated concentrations of toxicants based on current scientific information that, if not exceeded, are considered protective for organisms or a defined use of a water body. Standards Legal limits permitted by each state for a specific water body and thought to be sufficient to protect that water body. II. Water quality standards are the foundation of the water qualitybased control program mandated by the Clean Water Act (CWA). In the early days of EPA, the approach taken in an attempt to control toxics. This approach was referred to as the Best Available Technology (BAT) economically achievable or Technology Based Approach to Toxics Control. However, after best available technology economically achievable was in place all toxicity was not removed from industrial and/or municipal effluents. To attempt further control of toxics a program referred to as the Water Quality Based approach to toxics control was developed. In this approach biological and chemical methods are used to determine the presence of toxicity.

Water Quality Criteria

I. States and authorized Tribes adopt WQC to protect designated uses. Designated uses Those uses specified in water quality standards for each water body or segment whether or not they are being attained. They can: 1. adopt EPA's criteria under § 304(a) of the CWA 2. modify criteria to site-specific conditions 3. adopt other criteria that is scientifically defensible II. Water Quality monitored by numerical criteria, ambient toxicity tests, WET tests, biological surveys III. Other types of WQC include: sediment & nutrient criteria

Industrial processes and dioxins

Incineration of industrial and municipal wastes • Burning of some fuels • Bleaching of wood pulp for paper manufacturing process • Manufacture and application of some herbicides • Tobacco combustion, which gives rise to minute amounts of dioxin in cigarette smoke

Exposures to solvents

Inhaling vapors during use • Ingesting them in foods • Using foods and cosmetics packed in certain types of plastics • Smoking cigarettes • Working in a factory: chronic exposure • Inhaling vapors released by industrial facilities • Drinking solvent‐contaminated groundwater

Volatile Organic Compounds

Organic compounds that easily become vapors or gases. Contain one or more elements such as hydrogen, oxygen, fluorine, bromine, sulfur, and nitrogen Released from many commonly used solvents (Benzene, toluene, formaldehyde, styrene)

Aromatic Compounds

Organic molecules that contain a benzene ring EX: benzene and toleune

Major Classes of Pesticides

Organophosphates (OP) Organocarbamates (carbamates) Organochlorides (aka organochlorines and chlorinated hydrocarbons) Pyrethriods (class of pyrethrins)

Herbicides

Plant Killers Examples of chemicals in the category of herbicides and defoliants are: • Atrazine • Paraquat • Agent Orange (2,4‐D and 2,4,5‐T)

Potential Adverse Health Effects of DBPs

Possible adverse pregnancy outcomes - Stillbirths - Neonatal deaths • Possible increased risk of birth defects

Radiation Units

Roentgen (R): the quantity of ionization in air produced by x‐ or ‐rays • Rem: Roentgen equivalents in man, a complex mathematical way of calculating dose from Roentgens to tissue (Note: This an outdated way of looking at absorbed dose. Rads, sieverts, and grays are the more modern measures of radiation doses) Curie (Ci): A unit to describe the amount of radioactivity in a sample (1 mCi of P32) • Rad: Radiation absorbed dose

Radiation Poisoning: Alexander Litvinenko

Russian journalist who accused secret services of staging acts of terrorism to help bring Vladimir Putin to power: poisoned on 1 Nov 2006, died on 23 Nov. • Tea cup contained 210Po (alpha emitter) • Trails of were 210Po detected following Litvinenko and two former agents he had met with at a sushi bar

Notable dioxin exposures

Seveso, Italy • Passaic River, New Jersey • Love Canal • Nitro, West Virginia • Times Beach, Missouri • Kyushu, Japan • 2,4,5‐T manufacturing • Paper manufacturing • Wood treatment • Smelting

Anthropogenic air pollution

Stationary sources Mobile sources

Technological controls

Technological controls • Several mechanical devices are used to reduce industrial emissions of particulate matter (e.g., scrubbers, filters, and electrostatic precipitators).

Agent Orage Health Effects

The Institute of Medicine (U.S.) concluded that there was sufficient evidence that Agent Orange was associated with several forms of cancer: • Soft tissue sarcoma • Non‐Hodgkin's lymphoma • Hodgkin's disease • Chronic lymphocytic leukemia

Doses of Radiation

The radiation energy absorbed per unit mass of an organ or tissue and is used in studies of the damage to a particular organ or tissue.

Stochastic effects

The term stochastic means that there is an increased probability of the occurrence of an adverse health event. (Randomness of radioactive decay) • Carcinogenesis and genetic damage such as changes in DNA are possible stochastic effects of radiation exposure

Polychlorinated biphenyls

Two common uses before being banned: • Insulating fluid in transformers and capacitors • Lubricant • PCBs present in the environment tend to bioaccumulate in fish and other animals used for food and, in turn, impact human health. • Along with dioxins, an important contaminant for Superfund (500/1600 sites) - Hudson River (General Electric)

Radioactive elements

Unstable atomic nuclei • Decomposition/decay to form something more stable • During decay, energy and particles are emitted • The time it takes half of the mass of a radioactive substance to decay is called the "half life" • All elements can exist as slightly different forms called "isotopes" - the number of protons stays the same, but a different number of neutrons (C12, C13, C14)

Agent Orange

Used during the Vietnam War, during Operation Ranch Hand (1962 to 1971) • Approximately 19 million gallons of defoliants sprayed on 3.6 million acres in Vietnam and Laos • Contained small amount of dioxins

Styrene: plastics manufacturing

Used for the manufacture of polystyrene resins, which are components of many types of plastics • Short‐term inhalation of styrene can produce central nervous system effects such as muscle weakness, and problems concentrating on tasks; irritation of the respiratory tract also can result. • Possibly carcinogenic

Vinyl chloride

Used mainly for the manufacture of polyvinyl chloride, which is an ingredient in plastic products such as pipes, vinyl siding for houses, plastic coatings, and upholstery • Classified as a human carcinogen

DDT

Widespread use of DDT began during the early 1940s and reached a maximum during the 1960s. • Due to concerns about the possible adverse effects upon the health of humans and wildlife, application of DDT was prohibited in 1972 in the U.S. • Most developed nations banned the use of DDT; however, some countries still continue to use DDT Not regarded as a highly toxic pesticide • Formerly employed worldwide to control insects and harmful mosquitoes that carry malaria • Was credited at one time with saving millions of people from death due to malaria

Water Scarcity

• ". . . a country faces water scarcity when its annual supply of renewable freshwater is less than 1,000 cubic meters per person." • "Such countries can expect to experience chronic and widespread shortages of water that hinder their development."

Foodborne diseases

• ". . . illnesses acquired by consumption of contaminated food . . ." • Frequently called food poisoning, which is incorrect

Surface Water

• ". . . includes water from lakes, streams, rivers, and surface springs. It is vulnerable to contamination by a variety of human, animal, and industrial sources and therefore has been subject to some of the most stringent testing and treatment requirements."

Source Water

• ". . . the untreated and unfiltered water in rivers, streams, lakes, and aquifers from which water utilities draw water to be treated, filtered, and tested to produce drinking water."

Groundwater Under the Direct Influence of Surface Water

• ". . . water in aquifers that may be affected or contaminated by surface water." • "The EPA mandates more stringent testing, treatment, and filtration requirements for groundwater under the direct influence of surface water than for groundwater alone."

Finished Water

• ". . . water leaving the plant and ready to be used by consumers after being collected, treated, and, usually, filtered by a water utility."

Foodborne outbreak

• "...the occurrence of a similar illness among two or more people which an investigation linked to consumption of a common meal or food items, except for botulism (one case is an outbreak)."

Water Stress

• "A country faces water stress when its annual supply of renewable freshwater is between 1,000 and 1,700 cubic meters per person." • "Such countries can expect to experience temporary or limited water shortages."

Aquifer

• "A layer or section of earth or rock that contains freshwater, known as groundwater (any water that is stored naturally underground or that flows through rock or soil, supplying springs and wells)."

Global warming/climate change

• "An increase in the near surface temperature of the Earth. . . . [is] predicted to occur as a result of increased emissions of greenhouse gases." • "Scientists generally agree that the Earth's surface has warmed by about 1 degree Fahrenheit in the past 140 years." • 97‐98% of climate scientists agree on anthropogenic climate change • "Climate of Doubt" on PBS's Frontline

Reservoirs

• "Artificial lakes, produced by constructing physical barriers across flowing rivers, which allow the water to pool and be used for various purposes. The volume of water stored in reservoirs worldwide is estimated at 4,286 km3. . ."

Glaciers and Icecaps

• "Glaciers and icecaps cover about 10% of the world's landmass." • "These are concentrated in Greenland and Antarctica and contain ~70% of the world's freshwater."

Freshwater Lakes

• "Most freshwater lakes are located at high altitudes, with nearly 50% of the world's lakes in Canada alone." • "Many lakes, especially those in arid regions, become salty through evaporation, which concentrates the inflowing salts." Examples of major salt lakes are the Caspian Sea, Dead Sea, and Great Salt Lake.

Effects of botulism

• "Onset of symptoms in foodborne botulism is usually 18 to 36 hours after ingestion of the food containing the toxin, although cases have varied from 4 hours to 8 days." • Early signs: • Marked lassitude • Weakness and vertigo • Double vision • Progressive difficulty in speaking and swallowing • Difficulty in breathing • Abdominal distention • Constipation

Federal standards

• "Primary standards set limits to protect public health, including the health of 'sensitive' populations such as asthmatics, children, and the elderly." • "Secondary standards set limits to protect public welfare, including protection against decreased visibility, damage to animals, crops, vegetation, and buildings."

Water Withdrawal

• "Removal of freshwater for human use from any natural source or reservoir, such as a lake, river, or aquifer. If not consumed, the water may return to the environment and can be used again."

Hydrological (Water) Cycle

• "The natural cycle by which water evaporates from oceans and other water bodies, accumulates as water vapor in clouds, and returns to oceans and other water bodies as precipitation."

Runoff

• "Water originating as precipitation on land that then runs off the land into rivers, streams, and lakes, eventually reaching the oceans, inland seas, or aquifers, unless it evaporates first."

Wetlands

• "Wetlands include swamps, bogs, marshes, mires, lagoons and floodplains."

Health effects of air pollution

• 1892: London smog kills 1,000 people • 1939: St. Louis citizens need lanterns during the day for a week • 1952: London "killer fog" kills 4,700 people • 1953: New York smog kills 170‐260 people • 1962: London smog kills 750 people • 1963: New York smog kills 405 people - Clean Air Act passed.

Three Mile Island

• 28 Mar 1979: Coolant loss arising from mechanical failures caused a partial meltdown of the fuel rods. • Small amounts of radioactive noble gases were released. • No apparent health effects have been observed.

Uranium

• A common element in the earth's crust • Uranium ores uraninite and pitchblende are found in large amounts in North America, Africa, and Australia. • Nearly all plants, animals, and aquifers contain tiny amounts of uranium

Diesel exhaust

• A complex mixture of particles and gases; includes the element carbon, condensed hydrocarbon gases, and polycyclic aromatic hydrocarbons (PAHs), the latter suspected of being carcinogens. • Other constituents are hundreds of organic and inorganic compounds, some of which are regarded as toxic.

Water Facts

• A human can live up to a month without food, but can survive for about a week without water. • Average requirement for human consumption of water per day is approximately 2.5 liters (about 2 ½ quarts). • About two-thirds of the human body is made up of water. Two-thirds of the water used in an average home is used in the bathroom. • Typically 4 to 6 gallons of water are used for every toilet flush. • On the average, a person uses 2 gallons of water to brush his or her teeth each day. • A 10-minute shower uses about 55 gallons of water. • A leaking faucet can waste up to 100 gallons of water a day.

Global foodborne disease

• A major cause of morbidity (and occasionally mortality) in the United States and other countries of the world. • Incidence of foodborne illnesses has increased in industrialized nations.

Escherichia coli (O157:H7)

• A pathogenic strain; many E. coli strains are nonpathogenic. • Causes bloody diarrhea • 73,000 cases and 61 deaths annually in the U.S. • Major outbreaks in restaurant chains • Can be transmitted by many vehicles

Salmonellosis symptoms

• Acute symptoms (onset time 6‐48 hours) • Nausea • Vomiting • Abdominal cramps • Diarrhea • Fever • Headache • Chronic symptoms • May include arthritic‐like symptoms that occur 3‐4 weeks after an acute infection

Natural processes and dioxins

• Affects approximately 76 million persons each year in the United States. • Causes an estimated 9,000 deaths annually • Incurs an economic cost of $5 billion annually

Particulate Radiation

• Alpha () particles • Two protons and two neutrons: a helium nucleus • Dangerous if inhaled or ingested • Beta () particles • Electron • Penetrate much more deeply than alpha particles • Used in radiation therapy

Water Availability Facts

• Although the earth's surface (about 70%) is covered largely by water, most of this water is unusable ocean water. • Approximately 3% of all water is freshwater, of which the majority is unavailable for human use (e.g., frozen in icecaps). • Remaining 1% of readily accessible water comes from surface freshwater; sources include lakes, rivers, and shallow underground aquifers.

Temperature inversion

• An atmospheric condition during which a warm layer of air stalls above a layer of cool air that is closer to the surface of the earth • During a temperature inversion, pollutants can build up when they are trapped close to the earth's surface.

The Kyoto Protocol

• An international and legally binding compact that was initiated in Kyoto, Japan, in 1997. • Goal is to reduce emissions of greenhouse gases that are believed to be the cause of recent climate changes. • Requires developed countries to reduce their emissions by targeted amounts. For example, the U.S. would be required to cut emissions by 7% and European countries (Switzerland, Central and Eastern Europe, and the European Union) by 8%. • In order for the Kyoto Protocol to come into effect, it needed to be ratified by a sufficient number of industrialized countries that in combination produce at least 55% of the world's total CO2 emissions. • By January 2005, about 140 nations including Russia had ratified the protocol, meaning that it could be implemented. The Kyoto Protocol went into force on February 16, 2005. The U.S. did not sign.

Bovine spongiform encephalopathy

• An outbreak in 1986 affected 1 million cattle in U.K. • Reported in 20 European countries as well as Japan, Israel, and Canada • Cases have been reported in the U.S. (2003 and later). • Appears to be spread among cattle by feeds that contain rendered cattle products

IPCC Report

• April 2014 • Dire predictions for 2 C temperature increase • Sea level rise

Ionizing Radiation: Acute Effects

• At low levels: tissue burns and radiation sickness (e.g., nausea, weakness, and loss of hair) • Cutaneous radiation syndrome: skin burns • At high levels: capable of producing fatal injuries

Water Use in the U.S.

• Average person uses about 100 gallons (about 400 liters) of water per day. • Average residence uses over 100,000 gallons (about 400,000 liters) during a typical year. • Most of this household water (50-70%) is used for outdoor purposes such as watering lawns and washing cars.

Foodborne illness surveillance

• CDC maintains responsibility at the federal level. • CDC Foodborne Diseases Active Surveillance Network (FoodNet) • An active system whereby public health officials maintain frequent, direct contact with clinical laboratory directors to identify new cases of foodborne illness.

Environmental impacts

• Causes property damage • Reduces visibility in national parks • Harms forests • Harms lakes and other bodies of water • Injures wildlife

Clostridium botulinum

• Causes the foodborne disease botulism, a form of foodborne intoxication. • Grows in an anaerobic (oxygen‐free) environment and produces a potent toxin (a neurotoxin) that affects the nervous system.

RF Radiation and Cell Phones

• Cell phones are a very low power apparatus that transmits in the radiofrequency range of 900 to 1800 megahertz (MHz). • As of 2000, there were an estimated 92 million and 500 million cellular telephones in use in the U.S. and worldwide, respectively. • Widespread popularity of cell phones means that even small adverse health effects could have substantial implications for population health. • Cell phone antenna banks are themselves a source of RF radiation.

Increases in foodborne illness

• Changes in agricultural and food processing methods • Increasing globalization in food distribution • Social and behavioral changes among the human population

Potential Contaminants of Water That Flows across the Ground

• Chemicals and nutrients (e.g., fertilizers and nitrates from agricultural lands) • Rubber, heavy metals, sodium (from roads) • Petroleum byproducts and organic chemicals (from dry cleaners, service stations, and leaking underground storage tanks) • Chemicals used in the home (solvents, paints, used motor oil, lead, and copper) • Heavy metals and toxic chemicals (from factories) • Microbial pathogens (from human and animal wastes)

Water Disinfection Byproducts (DBPs)

• Chemicals used to disinfect water are associated with by-products of chlorination called DBPs. • These chemicals include chlorine, chloramines, chlorine dioxide, and ozone. • Chlorine is associated with trihalomethanes (THMs), which are among the most common and widely measured DBPs.

Natural sources of exposure to ionizing radiation

• Cosmic radiation (radiation from space) and uranium deposits, causes increases in background radiation levels in some geographic areas. • A decay product of uranium, radioactive radon gas may seep into homes, thus exposing the residents. • Pipe scale

Criteria air pollutants

• Criteria pollutants: "a group of very common air pollutants regulated by EPA on the basis of criteria (information on health and/or environmental effects of pollution)." • CO • O3 • NOx • SOx • PM • Pb

Global warming: potential impacts

• Disturbances in the native habitats of plant and animal species • Growth of vector‐borne diseases • Growth of organisms in the ocean that cause foodborne seafood poisoning • Exacerbation of the effects of air pollution • Extreme climatic conditions (e.g., heat waves, droughts, and monsoons) • Disruption of the food supply and dwindling of food resources

Stationary sources

• Electric generating plants • Factories and manufacturing complexes • Oil refineries • Chemical plants • Incinerators

Types of Ionizing Radiation

• Electromagnetic/photons • y‐rays, X‐rays • Particles • Protons, neutrons, alpha‐ and beta‐ particles

Examples of Waterborne Pathogens

• Enteric protozoal parasites • Bacterial enteropathogens • Viral pathogens • Other agents

Diesel exhaust: health effects

• Epidemiologic evidence suggests that in comparison with nonexposed groups, two categories of workers (truck drivers and railroad crews) exposed directly to diesel exhaust have lung cancer incidence rates that are 20% to 40% higher.

Effects of Beach and Coastal Pollution

• Excessive amounts of nutrients that enter the oceans may cause harmful blooms of algae, resulting in reduced levels of oxygen in the water (anoxic conditions). • An anoxic ocean environment can bring about fish kills and damage other forms of ocean life. • Urban runoff and sewage contamination of the ocean expose swimmers to waterborne diseases.

Medical Radiation

• Exposure of the population to ionizing radiation from medical procedures is the second largest source of exposure, about 40% • Medical procedures include the use of Xray machines, nuclear medicine, and radiation therapy

Non‐Ionizing Radiation

• Extremely low frequency (ELF) radiation (high tension power lines) • AM, FM, VHF‐TV radio waves • Microwave radiation • Infrared radiation (the source of heat in heat lamps used for keeping food warm) • Visible light radiation • Ultraviolet radiation (UVA, UVB, UVC)

Non‐Ionizing Radiation and Health Effects

• Extremely low frequency (ELF) radiation does not appear to produce many discernible short‐term health effects. • 50‐60 Hz, power poles/wiring/ appliances • Higher frequency levels (i.e., radiofrequency and microwave radiation) causes heating of the body.

National Ambient Air Quality Standards (NAAQS)

• Federal standards for air pollution • CO: 9ppm 8h TWA • PM2.5: 15 g/m3 8h TWA • The EPA reviews the scientific literature at 5‐year intervals and decides whether to revise each standard.

Treatment of Water from Aquifers

• For high-quality water from aquifers, minimal aeration, filtration, and disinfection are necessary. • In some cases, water drawn from aquifers is free from microorganisms, but undesirable for human consumption because of impurities and coloration that impair the esthetic qualities of this essential liquid.

Causes of GCC

• Greenhouse gases: CO2, CH4, NO, water vapor • Use of fossil fuels, including coal and petroleum‐based fuels. • Chlorofluorocarbon gases used in air conditioners have been linked to the depletion of the ozone layer.

Chronic effects of air pollution

• Heart disease • Chronic obstructive pulmonary disease • Lung cancer

Staphylococcus aureus

• Humans and animals are reservoirs. • Present in the nose and in skin lesions • Elaborates a toxin that is resistant to high temperatures • A frequent cause of foodborne outbreaks • Causes a foodborne intoxication with rapid onset

Energy conservation

• Increase the efficiency of older power plants. • Develop more renewable and alternative energy sources, e.g., wind turbines and solar panels. • Use energy‐efficient designs in home construction and electrical appliances; try to reduce dependence on such appliances. • Increase the fuel efficiency of motor vehicles as in the use of hybrid gas‐electric and other high mileage designs. • Increase the use of public transportation.

Radon

• Inert, colorless, and extremely toxic gas • Produced by the decay of radium and uranium, which are found universally in the earth's crust in varying amounts. • Classified as a Class A carcinogen • Causes long‐term adverse health effects

Acute effects of air pollution

• Irritation of the eyes, nose, and throat • Aching lungs • Bronchitis • Pneumonia • Wheezing • Coughing • Nausea • Headaches

NOx and SOx

• NOx: combustion causes reaction between oxygen and nitrogen (NO and NO2) • Causes smog and acid rain • Destroys stratospheric ozone • Can damage lung tissue (nitric acid vapor), cause asthma • SOx: formed by burning sulfur (e.g., in coal or diesel) • Can form sulfuric acid (acid rain, lung damage)

Toxins: food hazards

• Naturally occurring toxins, such as those from seafood and mushrooms, may be associated with foodborne illness.

Composition of ambient air

• Nitrogen (76%) • Oxygen (23%) • Argon (1%) • Carbon dioxide (0.03%) • Variety of other gases in lesser amounts • Water vapor

Man‐made sources of exposure to ionizing radiation

• Nuclear power plants have been known to (rarely) leak ionizing radiation • Radioactive fallout from above‐ground nuclear testing • Decommissioned and abandoned nuclear weapons facilities and storage of nuclear wastes • Medical X‐rays and radiation diagnostic and therapy procedures

Sources of Salmonella

• Occur widely in wild and domestic animal reservoirs • Animals that are used for human consumption—poultry, swine, cattle— may harbor Salmonella. • Pet animals such as cats, dogs, and turtles also can be reservoirs for Salmonella. • Some animals and birds are chronic carriers of the bacteria.

Petroleum Spills

• Oil spills from tankers and off-shore drilling platforms can have a devastating impact on the shoreline, aquatic life, mammals, and birds. • Worst spill in U.S. history was caused by the tanker Exxon Valdez in 1989. • Deep Water Horizon oil spill of 2010

Mobile sources

• On‐road vehicles (e.g., cars, trucks, buses) • Off‐road vehicles (e.g., dune buggies, snowmobiles) • Nonroad vehicles (e.g., airplanes, ships, trains) • According to the EPA, mobile sources produce nearly half of two major causes of smog—volatile organic compounds (VOCs) and nitrogen oxides (NOx), almost 90% of carbon monoxide, and more than half of hazardous air pollutants.

Particulate matter

• PM10 and PM2.5 • Particles of both sizes cause respiratory system irritation and impact the lungs. • PM2.5 particles are capable of being inhaled deeply into the lungs. • PM2.5 particles are not cleared readily from the body. • PM2.5 particles are associated with 60,000 deaths annually (U.S.).

Another Source of Water Contamination

• Pharmaceutical and personal care products (PPCPs) represent another source of water contamination. • They are washed off or excreted from the body. • Examples include: analgesics, oral contraceptive agents, drugs for lowering cholesterol, and anticonvulsants.

Examples: Indoor air pollutants

• Presence of cockroaches (asthma) • Persistent dampness (mold) • Wall‐to‐wall carpeting • Exposure to environmental tobacco smoke • Infestations with rodents • Pet dander • Effluents from gas stoves • Construction materials that contain formaldehyde • Dust mites • Molds • Bacterial agents

Other agents: prions

• Prions are hypothesized to be the cause of bovine spongiform encephalopathy (BSE), a neurological disease in cattle. • The course of BSE is progressive, ultimately fatal, and is potentially transmissible among cattle.

Salmonellosis

• Ranked among the most frequent types of foodborne illness in the U.S. • Approximately 2 to 4 million cases of salmonellosis (reported and nonreported) are estimated to occur each year in the U.S. • Causes about 500 deaths each year

Acid rain

• Refers to the precipitation of acidic compounds formed when components of air pollution (e.g., SO2 and NOx) interact with other components in the air such as water, oxygen, and oxidants. • Emissions of SO2 and NOx are produced by installations such as electric utility plants. • Creates abnormally high levels of acidity that are potentially damaging to the environment, wildlife, and human health.

Health Effects of Chemicals in the Water Supply

• Reported health effects have included: - Various cancers - Adverse reproductive outcomes - Cardiovascular disease - Neurological disease

Illness Associated with Poor Indoor Air Quality

• Sick building syndrome—no specific illness or cause can be identified. • Building‐related illness—describes a diagnosable illness

Fukushima Daiichi Disaster

• Six reactors in a plant: 4‐6 were shut down. 1‐3 shut down automatically after earthquake. • Tsunami flooded room where emergency generators powered circulating water pumps. Sea water was later used to cool the reaction. • Nuclear fuel in reactors 1‐3 melted down. • A change in phase of nuclear fuel means it is more likely to contaminate the environment. • Hydrogen gas was produced, causing small explosions. • Concerns: • Venting of radioactive gases. • Radioactive contamination of sea water which was then released to ocean. • Food grown in the region cannot be sold. • Fish with high levels of radiation caught near Fukushima two years after event.

Chemicals in the Water Supply

• Some chemicals that have been reported to cause adverse health effects: - Aluminum - Arsenic - Disinfection by-products - Fluoride - Lead - Pesticides - Radon

Fluoridation of Water

• Some communities in the United States add fluoride to public drinking water in order to prevent tooth decay. • Field trials conducted in the 1940s demonstrated a 50-70% reduction in the prevalence of dental caries.

Health effects of air pollution

• Some forms of cancer such as lung cancer and skin cancer (from possible depletion of the ozone layer) • Damage to vital tissues and organs, such as the nervous system • Impairment of lung and breathing function

Effects of C. perfringens

• Symptoms • Intense abdominal cramps • Diarrhea • Onset 8‐22 hours after consumption of incriminated food • Duration • Approximately 24 hours. • Mild symptoms may last for 1 or 2 weeks.

Tapeworm: infection effects

• Symptoms of taeniasis usually are limited to mild abdominal distress. • One of the main symptoms is the passage of the proglottids (the section of the worm that contains eggs) of T. saginata and T. solium in stools.

UV Radiation Index

• TUV index provides a measure of the amount of UV exposure that one is likely to have on a given day. • The index predicts UV intensity levels on a scale of 1 to 11+, where low indicates a minimal risk of overexposure and 11+ means an extreme risk. • Calculated on a next‐day basis for every ZIP code across the United States.

Tapeworms

• Taeniasis is a parasitic disease caused by tapeworms. • One form is caused by the beef tapeworm (Taenia saginata) and the other by the pork tapeworm (Taenia solium). • These organisms may induce human illness following the consumption of raw or undercooked infected beef or pork.

Reducing harmful air pollution

• Technological controls • The Kyoto Protocol • Energy conservation

Effects of UV Radiation

• Temporary conditions include burns and temporary blinding • Long‐term consequences: • Photoaging of the skin • Non‐melanoma skin cancer (NMSC) • Malignant melanoma (MM) • Retinal damage • Lens opacities

Air quality index

• The Air Quality Index is used to provide the public with an indication of air quality in a local area on a daily basis. (CO, NOx, SOx, O3, PM) • 0‐50: good • 51‐100: moderate • 101‐150: unhealthy for sensitives • 151‐200: unhealthy • 201‐300: very unhealthy • 301‐500: hazardous • It focuses on health effects you may experience within a few hours or days after breathing polluted air.

Clostridium perfringens

• The CDC estimates that about 10,000 cases occur each year in the U.S. • C. perfringens is anaerobic, rod‐shaped, and forms spores. • Occurs commonly in the environment (e.g., in soil and sediments), especially in those areas contaminated with feces • Also found in the intestines of humans and animals

Beach and Coastal Pollution

• The approximately 1 billion people who live near coastal areas cause great stress on coastal ecosystems. • Coastal areas are threatened by overdevelopment, poor planning, and economic expansion. • World's coastal regions are the recipients of billions of gallons of treated and untreated wastewater.

Nuclear Explosions

• The blast (damage to or destruction of buildings and those in them) • Heat (destruction or injury by high temperatures or fire) • Intense light (damage to eyesight) • Ionizing radiation causing Acute Radiation Syndromes of different degrees of severity • Persons near the nuclear explosion would experience thermal burns and radiationinduced skin injuries. • Major byproducts of the detonation of a nuclear weapon is radioactive fallout. • Radioactivity will dissipate over several weeks, but crops and food animals taken from the area may be unsuitable to consume.

Salmonella

• The infection is called salmonellosis. • Salmonella bacteria are: • Rod‐shaped • Motile • Gram‐negative • Non‐sporeforming • The most common serotypes in U.S. are: • Salmonella serotype Enteritidis • Salmonella serotype Typhimurium

Bacterial agents

• The pathogens Salmonella, Clostridium botulinum, Staphylococcus aureus, and Clostridium perfringens are bacteria‐‐ unicellular organisms that have characteristic shapes, e.g., rod‐shaped (in some instances a slender, curved rod), spherical (cocci), or spiral.

Transfer of Salmonella

• To environmental surfaces at work and at home (e.g., the kitchen) from raw meats, poultry, and seafood • From animal feces • From contaminated water and soil

Norovirus

• Transmitted easily within closed environments such as cruise ships • May be brought on board by passengers who fall ill just before embarking on a cruise • Crew members and ship‐board environmental contamination may act as disease reservoirs.

Foodborne illness: Trichinosis

• Trichinosis is a foodborne disease associated with eating meat that contains a nematode (also called a roundworm) from the genus Trichinella. • The classic agent of trichinosis is Trichinella spiralis, which can be found in many carnivorous and omnivorous animals (e.g., pigs, bears, walruses, rodents, and cougars).

Regions That are Facing Water Scarcity and Water Stress

• Two sections of the world that currently have severe water shortages also are experiencing some of the highest population growth rates in the world. - Africa (sub-Saharan and North) -Near East

Air pollution in the US

• U.S. produces 23% of the earth's emissions of greenhouse gases. • Major source of air pollution in the U.S. is combustion of fossil fuels, particularly by coal‐fired electric generating plants and internal combustion engines. • The U.S., with only about 4% of the world's population, is the leading source of carbon dioxide pollution.

Ultraviolet Radiation

• UVR coming from the sun is subdivided into UVA, UVB, and UVC, depending upon the wave length of the light. • Of the three forms of UVR, UVB is considered to be the form that is most harmful to health. • WHO has rated tanning beds as "carcinogenic to humans."

Indoor cooking stoves in the Third World

• Use biomass fuels • Often unventilated • Impact the health of children, women, and the elderly

Radiation and Science

• Use of hydrogen isotope tritium (3H) to label chemical substances (toxicodynamics/kinetics research), or DNA (how fast are cells proliferating?). • Use of 32P to see how proteins bind to DNA (electrophoretic mobility shift assay)

Tsutomu Yamaguchi

• Visited Hiroshima, Japan on during the summer of 1945 on business • Returned home the next day to his hometown, Nagasaki; went back to work on 9 Aug • Died of stomach cancer - age 93, on January 4 2010.

Norovirus symptoms

• Vomiting • Diarrhea • Dehydration • Abdominal cramps • These symptoms last from one to two days.

Treatment of Water for Residential Consumption

• Water supplied to the public in the U.S. undergoes treatment in order to meet quality standards set by the EPA for safe levels of chemical contaminants and water-borne microorganisms.

Nuclear Facilities and Accidents

• Weapons production plants, test sites, and nuclear power plants. • Three Mile Island accident: no new nuclear power plants have been built in the United States since 1979. • Chernobyl, Ukraine in 1986.

Ultraviolet Radiation Sources

• Welders' arcs • Tanning beds • Some lamps used in photography • Halogen desk lamps • Lightning • Electrical sparks • Sunbathing

Heavy metals

• When present in high concentrations, heavy metals can cause vomiting that occurs a few minutes to several hours (but in most cases in less than one hour) after ingestion.

Natural sources of air pollution

• Wind storms that spread dust clouds • Salt evaporation along the earth's coasts • Production of materials that have a biologic origin (e.g., mold spores, pollen, and organic material from plants and animals ) • Forest fires • Volcanic eruptions

Anthropogenic Ionizing Radiation

• X‐rays and other procedures used in medicine (medical tests and therapies) • Consumer products • Radioactive substances used in industry • Nuclear power generators • Radioactivity (e.g., radioactive fallout) from the production and detonation (primarily for testing purposes) of nuclear weapons.


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