General Pathology (Lec) Environmental Diseases PDF

miM GENERAL PATHOLOGY (LEC) S.Y. ‘24 - ‘25 | SEM 1 | UZZIEL P. PANES DDM 3-A – NOVEMBER 28, 2024 – CHERNOBYL NUCLEAR ACCIDENT (1986) 1.0 ENVIRONMENTAL DISEASES ENVIRONMENT ○ Outdoor, indoor, at home, at work, etc. PERSONAL ENVI...

miM GENERAL PATHOLOGY (LEC) S.Y. ‘24 - ‘25 | SEM 1 | UZZIEL P. PANES DDM 3-A – NOVEMBER 28, 2024 – CHERNOBYL NUCLEAR ACCIDENT (1986) 1.0 ENVIRONMENTAL DISEASES ENVIRONMENT ○ Outdoor, indoor, at home, at work, etc. PERSONAL ENVIRONMENT ○ Greatly affected by various factors: ENVIRONMENTAL DISEASES Tobacco use ○ Those disasters are unusual and Alcohol ingestion infrequent occurrences. Therapeutic and ○ Environmental diseases caused by non-therapeutic drug ingestion chronic exposure to relatively low Diet levels of contaminants, occupational ○ In fact, these factors in the personal injuries, and nutritional diseases are environment may have a larger effect widespread. on human health than the ambient ○ The International Labor Organization environment. has estimated that work-related injuries and illnesses kill approximately 2 million people per year globally. 1. Undernutrition is the single leading global cause of health loss. 2. Ischemic heart disease and cerebrovascular disease are the leading causes of death in developed countries. ENVIRONMENTAL DISEASES 3. In developing countries, infectious diseases ○ Conditions caused by exposure to constitute 5 of the 10 leading causes of chemical or physical agents in the death. ambien, workplace and personal a. Respiratory infections environment. b. Human Immunodeficiency ○ Includes nutritional diseases. Virus/Acquired Immunodeficiency Syndrome (HIV/AIDS) THALIDOMIDE “MIRACLE MEDICINE” c. Diarrheal disease DISASTER (1950) d. Tuberculosis e. Malaria Infectious Diseases in the Philippines (Top 10 Communicable Diseases in the Philippines) ○ Tuberculosis ○ Dengue fever ○ Pneumonia ○ Malaria ○ Infectious diarrhea MINAMATA DISEASE DISASTER (JAPAN, ○ Bronchitis 1960s) ○ Influenza ○ Acute febrile illness ○ HIV ○ Lower respiratory tract infection (LRTI) Eight out of the Top 10 causes of morbidity in the Philippines were communicable diseases! GEN. PATH SEM1 PAGE 1 REVIEWER miM GENERAL PATHOLOGY (LEC) S.Y. ‘24 - ‘25 | SEM 1 | UZZIEL P. PANES DDM 3-A 4. About 70% of all child deaths are attributed to b. Vector-borne diseases only five (5) preventable diseases. i. Approximately 29% of a. Pneumonia emerging diseases. b. Diarrheal disease ii. Increase of incidence may be c. Malaria related to environmental d. Measles changes (example: global e. Perinatal/neonatal infections and warming). prematurity 5. Worldwide mortality of children under 5 years 1.1 HEALTH EFFECTS OF CLIMATE CHANGE of age has declined. a. 27% decline in mortality under 5 years The Earth has been warming at an of age between 1990 and 2015. accelerating pace during the last 40 years. b. This decline however falls short of the ○ Since 1960, global average UN Millennium Development Goal of temperature has increased by 0.6°C. achieving a 67% decline by 2015. ○ Glacier and polar ice caps melting has c. In Central and West Africa, figures accelerated. show there is no significant decline. ○ Sea level has risen to 1-2 mm/year due to thermal expansion. 6. Emerging Infectious Diseases (EIDs) constitute one of the most important THE GREENHOUSE EFFECT components of the global burden of disease. ○ Human activity is a major contributor a. Disease caused by newly evolved to the GREENHOUSE EFFECT. strains or organisms. Carbon Dioxide (CO2) i. Multidrug resistant Methane tuberculosis (MDR-TB) Ozone ii. Chloroquine-resistant malaria ○ Greenhouse gases along with water iii. Methicillin-resistant vapor act like a blanket, absorbing Staphylococcus aureus energy radiated from the Earth’s (MSRA) surface (supposedly lost into space) b. Diseases caused by pathogens that and trap heat. have been present in human populations but show a recent increase in incidence. i. Dengue fever c. Diseases caused by pathogens are endemic in other species and recently entered human populations. i. HIV - originally from nonhuman primates. ii. Severe Acute Respiratory Syndrome (SARS) - originally from birds, mammals. BUILDUP OF CO2 AND OZONE 7. Bacteria and Rickettsia caused approximately 54% of worldwide emerging infectious diseases during the past 60 years. a. Drug-resistant bacteria i. Most important group of pathogens. ii. Appearance is related to antibiotic use (or misuse) and Climate change will seriously impact human spread in densely-populated health by increasing incidence of several areas. diseases. GEN. PATH SEM1 PAGE 2 REVIEWER miM GENERAL PATHOLOGY (LEC) S.Y. ‘24 - ‘25 | SEM 1 | UZZIEL P. PANES DDM 3-A Airborne microorganisms CARDIOVASCULAR, Caused by heat waves and air contaminate food and water. CEREBROVASCULAR, pollution. Chemical and particulate RESPIRATORY pollutants. DISEASES ○ Classified as either: Outdoor air pollution GASTROENTERITIS Caused by water and food Indoor air pollution AND INFECTIOUS contamination from floods or DISEASE EPIDEMICS disruptions of water supply. OUTDOOR AIR POLLUTION VECTOR-BORNE Changes in vector number and INFECTIOUS DISEASES geographic distribution caused (E.G DENGUE FEVER) by temperature changes. MALNUTRITION Caused by disruption of crops, mostly by heat or heavy rainfall. 1.2 TOXICITY OF CHEMICAL AND PHYSICAL AGENTS The definition of a POISON is not OZONE straightforward. ○ Result of the interaction of UV It is basically a quantitative concept strictly radiation and oxygen (O2). dependent on the dosage. ○ In the stratosphere, forms the ozone layer, which protects life on Earth. ○ In the lower atmosphere, ground-level ozone is one of the most harmful air pollutants. Production of free radicals that cause injury to the XENOBIOTICS respiratory tract cells → ○ “Xeno” = stranger inflammation. ○ Exogenous chemicals in the environment in air, water, food and soil that may be absorbed into the body through inhalation, ingestion & skin contact. Chemicals may act at the site of entry or may act at other sites following transport through blood. ○ Xenobiotics may be eliminated in urine, feces, or expired air, or may PARTICULATE MATTER (SOOT) accumulate in bone, fat, brain, or other ○ Emitted by coal- and oil-fired power tissues and cause toxicities. plants, by industrial processes burning these fuels, and by diesel exhaust. ○ Fine or ultrafine particles less than 1.3 ENVIRONMENTAL POLLUTION 10μm in diameter are considered most harmful. AIR POLLUTION CARBON MONOXIDE (CO) ○ Air is often loaded with many potential ○ Non-irritating, odorless, colorless, causes of disease. tasteless gas produced by incomplete oxidation of carbon materials. ○ CO is an induced air pollutant, and is GEN. PATH SEM1 PAGE 3 REVIEWER miM GENERAL PATHOLOGY (LEC) S.Y. ‘24 - ‘25 | SEM 1 | UZZIEL P. PANES DDM 3-A also an important cause of accidental Penetration & suicidal death. Perforation Can induce coma within 5 minutes of getting trapped in PATTERNS OF MECHANICAL TRAUMA a small garage with average car exhaust. Kills by inducing Central Nervous System depression. CARBON MONOXIDE (CO) SOURCES AND POISONING THERMAL INJURY ○ Thermal burns result from injuries caused by fire, smoke inhalation and heat-related injuries. ○ The clinical significance of a burn injury depends on the following INDOOR AIR POLLUTION factors: ○ Most common indoor pollutant is Depth of burns. TOBACCO SMOKE. Percentage of body surface ○ Other indoor pollutants include: area (BSA) involved. Carbon monoxide (CO) Internal injuries caused by Nitrogen dioxide inhalation of hot/toxic fumes. Asbestos Promptness & efficacy of Bioaerosols therapy (e.g. fluid & electrolyte Radon management,infection Formaldehyde control)/ ○ Wood smoke contains particles that are predisposed to lung infections and CLASSIFICATION OF THERMAL BURNS cancer. SUPERFICIAL BURNS Confined to the epidermis; (FIRST-DEGREE BURN) blister formation. 1.4 INJURY BY PHYSICAL AGENTS Mechanical Trauma Thermal Injury Electrical Injury PARTIAL THICKNESS Involves the dermis and Injury by ionizing radiation BURN (SECOND epidermis. DEGREE BURN) MECHANICAL TRAUMA ○ Injury caused by mechanical forces with type of injury depending on the: Shape of the colliding object. Amount of energy discharged at impact. FULL THICKNESS Extends to the subcutaneous Tissues or organs that bear BURN (THIRD DEGREE tissue, or even muscle. the impact. BURN) ○ All soft tissues react in certain patterns of mechanical trauma: Abrasion Contusion Laceration Incision GEN. PATH SEM1 PAGE 4 REVIEWER miM GENERAL PATHOLOGY (LEC) S.Y. ‘24 - ‘25 | SEM 1 | UZZIEL P. PANES DDM 3-A HYPOTHERMIA COMPLICATIONS OF THERMAL BURNS ○ Prolonged exposure to low ambient ○ Shock, sepsis and respiratory temperature causing drop in body insufficiency are the greeted threats temp. to life in burns. ○ High humidity, wet clothing & dilation More common in burns of superficial blood vessels due to involving >20% of body ingestion of alcohol hastens drop in surface area → loss of liquid body temp. and protein. ○ Causes injury by two mechanisms: The burn site is ideal for Direct effects on cells. opportunistic microbial Indirect effects by circulatory growth (e.g. Pseudomonas changes ischemic injury aeruginosa) gangrene. ○ Organ system failure resulting from burn sepsis. ELECTRICAL INJURY Severe but rare complications ○ Often fatal injuries that arise from due to adequate infection contact with low-voltage currents at control nowadays. home/work, or high-voltage currents in ○ Injury to the airways and lungs. high-power lines or lightning. May develop within 24-48 ○ Electrical injuries are of two types: hours as a result of direct heat Burns on the mouth/nose/upper Ventricular fibrillation or airways due to inhalation of cardiac/respiratory failure heated air and noxious gases. ○ Alternating current (at homes) induces a tetanic muscle spasm irreversible HYPERTHERMIA clutching prolonging period of ○ Prolonged exposure to elevated exposure. ambient temperatures can result in the ff: Heat Cramps Result from loss of electrolytes from sweating. Cramping of voluntary muscles is the hallmark. Heat Exhaustion RADIATION Most common, ○ Radiation is energy that travels in the sudden-onset form of waves or high-speed particles collapse and and has a wide range of energies prostration. along the electromagnetic spectrum. Heat Stroke ○ Non-ionizing radiation Due to failure of Sources include UV, infrared, thermoregulatory microwave & sound waves functions (no motion/vibration of atoms. sweating, core temp ○ Ionizing radiation >40°C). Sufficient energy to remove Marked generalized tightly-bound electrons vasodilation with release of electrons. peripheral Main sources include X-rays & pooling/congestion. Gamma rays, high-energy neutrons, α & ß particles. A double-edged sword – very useful in diagnostics & cancer GEN. PATH SEM1 PAGE 5 REVIEWER miM GENERAL PATHOLOGY (LEC) S.Y. ‘24 - ‘25 | SEM 1 | UZZIEL P. PANES DDM 3-A treatment, but also produces effects such as fibrosis, carcinogenesis and teratogenesis. INJURY PRODUCED BY IONIZING RADIATION Main Determinants of Biologic Effects of Ionizing Radiation: Rate of delivery Field size (exposure) Cell proliferation ○ Ionizing radiation damages DNA; rapidly-dividing cells are more vulnerable to injury. Oxygen effects and hypoxia Vascular damage TISSUES WITH HIGH RATE OF DIVISION ARE EXTREMELY VULNERABLE TO RADIATION FIBROSIS CAUSED BY RADIATION THERAPY GEN. PATH SEM1 PAGE 6 REVIEWER