Environmental Factors in Healthcare

Cheatsheet Content

Water and Health Physical Environment External conditions and surroundings that influence a person's health. Includes: Land, Air, Water, Plants and animals, Buildings and other infrastructure, Natural resources. People interact with their physical environment through air, water, homes, and transportation. A clean, healthy environment is important for physical and emotional well-being. What is Water? Colorless, transparent chemical substance. Main constituent of streams, oceans, and lakes. Chemical formula: $H_2O$ (two hydrogen atoms, one oxygen atom held by covalent bonds). 71% of Earth's surface is water. States of Water Solid: Ice (freezes at $0^\circ C$). Liquid: Most of Earth's surface, used in various applications. Gaseous: Water vapor (boils at $100^\circ C$). Physical and Chemical Properties of Water Colorless and tasteless liquid. Higher thermal conductivity, specific heat, surface tension compared to other liquids. Universal solvent (dissolves acids, salts, sugar, gases). Forms azeotropes with other solvents. Low electrical conductivity (improves with ionic substances). Importance of Water Agriculture: Key for irrigation and food production. Health: Human body is 50-78% water; needs 7 liters daily to avoid dehydration. Important for digestion and other biological processes. Maintains body's pH. Helps move antibodies in the immune system. Regulator: Helps regulate body temperature through cooling effects. Detoxification: Removes harmful toxins via perspiration and urination, prevents waste buildup. Washing: Used to make emulsions and solutions for cleaning. Water Cycle (Hydrologic Cycle) Continuous movement of water from Earth's surface to atmosphere and back. No starting or ending point; water circulates through solid, liquid, and gas states. Assisted by sun's energy, air currents, etc. Stages of Water Cycle Evaporation and Transpiration: Sun heats water bodies, causing evaporation. Plants lose water vapor (transpiration). Vapors rise. Condensation: Rising vapors cool and turn into liquid, forming clouds. Precipitation: Clouds become water-laden, releasing water as rain, hail, snow, or sleet onto Earth's surface. Runoff and Infiltration: Precipitation runs off into oceans/rivers or infiltrates soil. Water Distribution on Earth 97% of Earth's water is in oceans (saltwater). 2.5% is freshwater. A fraction of freshwater is frozen in glaciers and icebergs. Water Pollution and Control Definition of Water Pollution Contamination of water bodies (rivers, lakes, oceans, groundwater, aquifers) by industrial and agricultural effluents. Adversely affects all life forms and ecosystems. Sources of Water Pollution (India) Urbanization Deforestation Industrial effluents Social and Religious Practices Use of Detergents and Fertilizers Agricultural run-offs (insecticides, pesticides) Effects of Water Pollution Water bodies near urban areas: Extremely polluted due to garbage and toxic chemicals. Aquatic life: Drastically affected; impacts metabolism, behavior, causes illness and death. Dioxin bioaccumulates in fish. Food chain: Disrupts food chain; toxic substances like cadmium and lead move up the chain. Humans: Contract diseases (e.g., hepatitis, cholera) from contaminated water. Ecosystem: Critically affected, modified, and restructured. Minamata Incident Worst case of water pollution (1932, Minamata City, Japan). Factory dumped industrial effluent (Methylmercury) into surrounding bay. Methylmercury is highly toxic, causing neurological disorders in humans and animals. Led to "dancing cat disease" and acute mercury poisoning in humans. Pollution of the Ganges Sixth most polluted river globally. Hundreds of industries release effluents; religious activities (burials, cremations) contribute. Poses serious health risks (typhoid, cholera). Drives species to extinction (e.g., Ganges River shark, Ganges River dolphin). Water Scarcity By 2026, 4 billion people may face water shortage. Currently, 1.2 billion people lack access to clean, potable water. Groundwater is also susceptible to pollution. Control Measures for Water Pollution Treat sewage waste before discharge to reduce toxicity. Secondary treatment allows reuse in sanitary systems and agriculture. Water Hyacinth can absorb dissolved toxic chemicals. Chemical methods: precipitation, ion exchange, reverse osmosis, coagulation. Individual actions: reusing, reducing, recycling. Water Purification Definition Process of removing undesirable chemicals, biological contaminants, suspended solids, and gases from water. Goal: Produce water fit for specific purposes (drinking, medical, industrial). Methods of Water Purification Physical processes: Filtration, sedimentation, distillation. Biological processes: Slow sand filters, biologically active carbon. Chemical processes: Flocculation, chlorination. Electromagnetic radiation: Ultraviolet light. Water Purification Benefits Reduces particulate matter (suspended particles, parasites, bacteria, algae, viruses, fungi). Reduces dissolved and particulate matter concentration. Ensures access to pure drinking water. Water Treatment Steps (Typical) Pumping and Containment: Water pumped from source into pipes/tanks (using appropriate materials). Screening: Removes large debris (sticks, leaves, rubbish) from surface water. Storage: Water stored in bankside reservoirs for natural biological purification. Pre-chlorination: (Largely discontinued due to adverse effects) Chlorinated to minimize fouling organism growth. pH adjustment: Pure water pH is $\approx 7$. Seawater pH is $7.5-8.4$. Acidic water (pH $ Alkaline water (pH $> 7$): Add carbonic acid, hydrochloric acid, or sulfuric acid to lower pH. Alkalinity aids coagulation/flocculation and reduces corrosiveness to iron pipes. Coagulation/Flocculation: Coagulation: Add alum/liquid sulfate to raw water; dirt particles coagulate into flocs. Flocculation: Coagulated water mixes, particles collide to form larger flocs. Sedimentation: Flocs settle at the bottom of sedimentation basins, forming sludge. Removes large particles and microbes. Filtration: Water passes through sand, gravel, or crushed anthracite filters to remove particles. Disinfection: Disinfects water (e.g., with chlorine) to remove disease-causing bacteria, viruses, parasites. Oxidation: Removes inorganic contaminants (iron, manganese), destroys odor-causing compounds. Adsorption: Removes organic and inorganic contaminants by accumulation on solid adsorbents (metal oxide, activated carbon). Fluoridation: Adds fluoride to prevent dental cavities. Water Quality Standards set by governments/international bodies. Involves physical, chemical, hydrological, and biological characteristics. "Water quality" defined by user's acceptability (e.g., pure, wholesome for drinking). Visual inspection is insufficient; chemical and microbiological analysis is needed. Water Quality Criteria (Example Table) Designated-Best-Use Class of Water Criteria Drinking Water Source without conventional treatment but after disinfection A Total Coliforms Organism MPN/100ml $\le 50$ pH $6.5-8.5$ Dissolved Oxygen $\ge 6$mg/l Biochemical Oxygen Demand 5 days 20C $\le 2$mg/l Outdoor bathing (Organised) B Total Coliforms Organism MPN/100ml $\le 500$ pH $6.5-8.5$ Dissolved Oxygen $\ge 5$mg/l Biochemical Oxygen Demand 5 days 20C $\le 3$mg/l Drinking water source after conventional treatment and disinfection C Total Coliforms Organism MPN/100ml $\le 5000$ pH $6-9$ Dissolved Oxygen $\ge 4$mg/l Biochemical Oxygen Demand 5 days 20C $\le 3$mg/l Propagation of Wild life and Fisheries D pH $6.5-8.5$ Dissolved Oxygen $\ge 4$mg/l Free Ammonia (as N) $\le 1.2$mg/l Irrigation, Industrial Cooling, Controlled Waste disposal E pH $6.0-8.5$ Electrical Conductivity at 25C $\le 2250$ micro mhos/cm Sodium absorption Ratio Max. $26$ Boron Max. $2$mg/l Not Meeting A, B, C, D & E Criteria Below-E Air Pollution & Its Control Definition Release of harmful gases, particles, biological molecules into the air. Harmful to human health and environment. What is Air Pollution? Physical, chemical, or biological change in the air. Contamination by harmful gases, dust, smoke. Affects plants, animals, and humans. Imbalance in atmospheric gas composition (e.g., increase in $CO_2$ causes global warming). Types of Air Pollutants Primary Pollutants: Directly cause air pollution (e.g., sulfur dioxide from factories). Secondary Pollutants: Formed by interaction of primary pollutants (e.g., smog from smoke and fog). Causes of Air Pollution Burning of Fossil Fuels: Emits sulfur dioxide, carbon monoxide (incomplete combustion). Automobiles: Emit gases (greenhouse gases) from jeeps, trucks, cars, buses. Agricultural Activities: Ammonia, insecticides, pesticides, fertilizers emit harmful chemicals. Factories and Industries: Main source of carbon monoxide, organic compounds, hydrocarbons, chemicals. Mining Activities: Release dust and chemicals, deteriorating air quality and worker health. Domestic Sources: Household cleaning products and paints release toxic chemicals. Effects of Air Pollution Diseases: Respiratory disorders, heart diseases, lung cancer, pneumonia, asthma. Global Warming: Greenhouse gas emissions cause temperature increase, melting glaciers, rising sea levels. Acid Rain: Nitrogen oxides and sulfur oxides from fossil fuels react with water droplets, damaging life. Ozone Layer Depletion: Chlorofluorocarbons (CFCs), halons, hydrochlorofluorocarbons deplete ozone layer, causing harmful UV radiation exposure, skin diseases. Effect on Animals: Pollutants affect aquatic life, compel animals to shift habitats, leading to extinction. Air Pollution Control Measures Avoid Using Vehicles: Use public transport or walk for shorter distances. Energy Conservation: Switch off electrical appliances, use energy-efficient devices (e.g., CFLs). Use of Clean Energy Resources: Solar, wind, geothermal energies. Minimize Fire Use: Reduce use of fire and fire products. Control Industrial Emissions: Treat pollutants at source, substitute raw materials. Fuel Substitution: Replace petrol/diesel with cleaner fuels (e.g., CNG). Equipment Modification: Modify/maintain industrial equipment to minimize emissions. Process Control Equipment: Use equipment to control pollution when source control is not possible. Dilution: Dilute air pollutants. Tree Plantation: Trees reduce pollutants in the air. Noise / Sound Pollution Definition Unpleasant and undesirable sound leading to discomfort. Intensity measured in decibels (dB). Sources: Vehicles, aircraft, industrial machines, loudspeakers, crackers, high-volume appliances. Types of Noise / Sound Pollution Transport Noise: Traffic noise (vehicles), leading to hearing issues, headaches, hypertension. Neighbourhood Noise: From gadgets, household utensils, musical instruments, loudspeakers. Industrial Noise: High-intensity sound from heavy industrial machines, damages hearing. Causes and Sources Industrialization: Heavy machinery, generators, mills, exhaust fans. Vehicles: Increased number of vehicles. Events: Weddings, public gatherings with loudspeakers. Construction Sites: Mining, building construction. Examples of Noise Pollution Unnecessary usage of horns. Loudspeakers for religious/political functions. Fireworks. Industrial noise. Construction noise. Noise from transportation (railway, aircraft). Effects of Noise / Sound Pollution on Human Health Hypertension: Elevated blood pressure. Hearing Loss: Damage to eardrums from loud noise exposure. Sleeping Disorders: Fatigue, low energy, irritation. Cardiovascular Issues: Heart problems, stress, sudden changes in existing conditions. Prevention of Noise / Sound Pollution Ban honking in public places (hospitals, schools). Install soundproof systems in commercial, hospital, industrial buildings. Control musical instrument sounds. Dense tree cover. Avoid explosives in forests, mountains, mining areas. Ventilation – Pollution and Control What is Ventilation? Essential for indoor spaces, affects human health, comfort, well-being. Ensures continuous flow of fresh air, expelling pollutants, odors, moisture. Replaces stale indoor air with fresh outdoor air. Maintains indoor air quality, regulates temperature/humidity, prevents harmful pollutant buildup. How Ventilation Affects Pollution Dilution of pollutants: Introduces fresh air, diluting pollutants from indoor sources (cleaners, cooking, building materials). Moisture and Mold control: Good airflow controls humidity, preventing mold/mildew growth. Expelling contaminants: Mechanical exhaust systems (kitchen hoods, bathroom fans) remove pollutants outdoors. Health impact: Poor ventilation allows pollutants to accumulate, leading to respiratory issues, heart problems, neurological effects (headaches, fatigue). Sources of Indoor Pollution Chemical and material emissions: VOCs and formaldehyde from paints, cleaning supplies, new furniture, building materials. Combustion sources: Particulate matter, toxic gases (CO, $NO_2$) from fuel-burning appliances (stoves, fireplaces), tobacco smoke. Biological pollutants: Mold, dust mites, pet dander, pollen, bacteria, viruses thrive in humid environments. Outdoor infiltration: External pollutants (traffic emissions, industrial smoke) enter through windows, doors. Strategies for Controlling Indoor Pollution Source Control: Reduce/eliminate pollution sources. Clean cooking and heating: Use cleaner fuels (LPG, electricity, solar), low-emission stoves. Material and chemical use: Choose low-VOC paints, cleaning supplies, building materials; use strong ventilation during activities. Moisture management: Control humidity, repair leaks, run exhaust fans. Ventilation Methods: Natural ventilation: Open windows/doors for cross-ventilation. Mechanical ventilation: Fans and ducted systems for reliable airflow. Spot ventilation: Outdoor-vented exhaust fans in bathrooms/kitchens. Dilution ventilation: Whole-building systems to remove/replace indoor air with filtered outdoor air. Heat/Energy recovery ventilators (HRV/ERV): Exchange indoor/outdoor air while recovering heat/energy. Hybrid (mixed-mode) ventilation: Natural ventilation with mechanical backup for poor conditions. Air Cleaning and Filtration: High-efficiency particulate air (HEPA) filters: Trap airborne particles (dust, PM2.5, pollen, dander, mold spores, viruses, bacteria). Activated carbon filters: Absorb gases, odors, chemicals (VOCs, formaldehyde). Purifier placement: Place portable air cleaners in high-use areas, appropriately sized. Biological Environment Definition Living (biotic) and non-living (abiotic) elements of an ecosystem affecting organisms' growth, development, survival. Factors can be natural or human-induced. Biotic (Living) Factors Living organisms: Interactions impact survival. Producers, consumers, decomposers: Role in food web. Predators and prey: Influence population cycles. Competitors and parasites: Limit population growth, affect health. Physiological influences: Internal factors affecting health/development. Genetics: Inherited DNA for traits, abilities, health conditions. Hormones: Regulate growth, metabolism, sexual maturation. Metabolism and gut microflora: Crucial for bodily functions, energy, immunity. Abiotic (Non-living) Factors Air and water: Quality critical for life; pollutants cause disease/damage. Climate, temperature, and light: Influence biological processes, species distribution. Temperature: Regulates metabolic rates, growth, reproduction. Light: Primary energy source for photosynthesis, influences biological rhythms. Climate: Long-term weather patterns determine surviving species. Soil and nutrients: Habitat for microorganisms, anchors plants; vital for food production, ecosystem stability. Physical environment: Geographical features (altitude, landforms, water bodies) influence characteristics, disease spread, habitats. Social Environmental Factors Definition Social structures and relationships influencing individual behavior, health, development, opportunities. Range from immediate interactions to societal norms, policies, neighborhoods. Key Social Environmental Factors Social relationships and support networks: Quality and stability of connections impact mental/physical health. Socioeconomic status (SES): Education, income, occupation affect health/opportunities. Education and employment: Higher levels linked to better prospects, resources. Income and wealth: Economic factors influence access to food, healthcare, housing. Neighbourhood and community conditions: Characteristics of living places affect well-being. Safety and social cohesion: Crime rates cause stress; strong cohesion improves health. Access to resources: Availability of amenities (grocery stores, clinics, transport) affects lifestyle. Cultural factors and social norms: Shared values, beliefs, customs, practices influence behaviors. Socialization: Learning behaviors from family, peers, media. Stigma and discrimination: Prejudice, racism, homophobia affect mental/physical health. Gender and age: Roles, expectations, resource distribution create specific health risks. Values and beliefs: Guiding principles influencing perception of right/wrong. Impact on consumer behavior: Cultural values influence purchasing patterns. Influence on work ethic: Attitudes toward work, money, achievement. Language and communication: Shapes how people communicate, perceive world. Marketing and business: Language differences affect message interpretation. Social interaction: Communication styles influence negotiations, relationships. Religion: Religious/spiritual beliefs influence moral principles, traditions, daily practices. Lifestyle and food habits: Religion dictates dietary restrictions (e.g., pork, beef). Health and medicine: Beliefs about illness, healing practices affect health-seeking. Customs and traditions: Rituals and social norms passed down generations. Rituals: Cultural rituals influence buying patterns. Social norms: Unspoken rules about etiquette, space, dress codes. Social organization: Structured by patterns, classes, gender roles. Family and identity: Family/community influence decisions in collectivistic cultures. Impact on health: Social hierarchy, gender roles affect access to resources, healthcare. Material culture and aesthetics: Tangible aspects (tools, technology, art) and ideas of beauty/taste. Technology: Influences products/services available. Art and design: Preferences influence product design, packaging, marketing. Economic Environmental Factors Definition External conditions influencing economy, business, consumer behavior, financial stability. Macroeconomic (large-scale) and microeconomic (individual/industry-specific) levels. Macroeconomic Factors Economic growth and cycles: Expanding economy (GDP growth) leads to consumer spending, investment, job creation. Recession means declining activity, job losses. Inflation: Rate at which prices rise, reducing purchasing power. Impact on businesses: Increases production costs, squeezes profit margins. Impact on consumers: Erodes disposable income, cuts non-essential spending. Interest rates: Affect cost of borrowing for businesses/consumers. Impact on businesses: High rates make expansion expensive. Impact on consumers: High rates reduce spending on major purchases. Unemployment rate: High rate signals sluggish economy, less disposable income. Low rate indicates stability. Government fiscal policies: Taxation and spending affect disposable income, business profitability. Expansionary policy: Tax cuts/increased spending stimulate economy, job growth. Contractionary policy: Increased taxes/spending cuts cool economy, combat inflation. Exchange rates: Currency value affects international trade. Impact on businesses: Fluctuating rates affect import/export profitability. Impact on consumers: Weaker domestic currency makes imports expensive. Consumer confidence: Confidence in financial future drives economic growth. Microeconomic Factors Consumer behavior and demand: Influenced by income, confidence, preferences. Competition and market structure: Influences pricing, innovation, market share, profit. Supply chain and supplier conditions: Availability/cost of raw materials, reliability of distribution channels. Political and Legal Factors Affecting Health Definition Shape systems, policies, regulations influencing living conditions, behaviors, access to care. Political Factors Political decisions and government priorities: "Political determinants of health" influence resource allocation, social structures. Government spending and resource allocation: Prioritization of public health: Funding for infrastructure, sanitation, preventative care. Broader social spending: Funding for education, housing, social welfare addresses root causes of health inequities. Policy and regulation: Health policy: Prioritizes preventive care, universal health coverage (e.g., Ayushman Bharat scheme). Non-health policies: Urban planning, environmental regulation, green spaces promote health. Political stability and democracy: Rule of law and governance: Accountable systems protect health rights. Citizen participation: Engagement in political process influences policies. Legal Factors Positive impacts of law and regulation: Setting standards and promoting healthy behaviors: Laws for seatbelt use, smoking bans, nutrition labeling, vaccinations. Protecting patients and ensuring quality care: Medical malpractice laws, licensing, privacy regulations (HIPAA). Advancing social justice and health equity: Reforms addressing poverty, discrimination. Negative or restrictive impacts of law: Discriminatory laws: Stigmatize marginalized groups (e.g., punitive drug laws, housing policies). Barriers to service delivery: Restrictive laws on scope of practice, telehealth adoption. Unintended consequences: Laws can have negative effects (e.g., criminal justice laws affecting minorities). Technological Factors and Natural Factors in Health Care Definition Profoundly impact healthcare delivery, treatments, and population health. Technological Factors in Healthcare Positive impacts: Improved diagnostics and treatment: Advanced imaging (MRI), AI-assisted diagnostics, robotics, 3D printing (prosthetics, tissues). Enhanced patient access and management: Telemedicine, remote monitoring, health apps, wearable devices. Greater operational efficiency: EHRs streamline tasks, improve communication, provide holistic patient view. Big data analytics: Identify risk factors, predict patient loads, develop personalized treatments. Challenges and negative impacts: Physical and mental health risks for users: Screen time issues ("tech neck"), disrupted sleep. Data security and privacy concerns: Cyberattacks, breaches, misuse of sensitive data. Exacerbating health inequities: High costs, limited digital infrastructure, digital literacy widen gaps. Ethical implications and accountability: Algorithmic bias, patient consent, error accountability. Natural Factors in Healthcare Definition: Fundamental determinants of health, affecting human well-being and healthcare systems. Air and water quality: Air pollution: Leads to respiratory diseases, cardiovascular problems, lung cancer. Water contamination: Causes infectious diseases (cholera, typhoid, dysentery). Climate change and extreme weather events: Health emergencies: Heatwaves, floods, wildfires, storms lead to injuries, illness, deaths. Disrupted food and water systems: Food insecurity, water quality issues, undernutrition, water-borne diseases. Strain on healthcare systems: Natural disasters damage facilities, disrupt supply chains, increase demand. Built and urban environments: Urban planning: Design of cities promotes/hinders health (walkable neighborhoods, green spaces). Housing and sanitation: Poor conditions, overcrowding, inadequate sanitation lead to infectious disease transmission. Ecosystem and biodiversity: Biodiversity and disease: Healthy ecosystems prevent outbreaks; degradation increases risk of novel diseases. Natural resources for medicine: Source of compounds for new medicines.