PH 136 Environmental Health Introduction PDF PDF

PH 136: ENVIRONMENTAL AND OCCUPATIONAL HEALTH INTRODUCTION TO ENVIRONMENTAL & OCCUPATIONAL HEALTH Sir Francis Andrew B. Cube | January 23, 2025 ​ Aims to prevent disease by enabling health-supportive...

PH 136: ENVIRONMENTAL AND OCCUPATIONAL HEALTH INTRODUCTION TO ENVIRONMENTAL & OCCUPATIONAL HEALTH Sir Francis Andrew B. Cube | January 23, 2025 ​ Aims to prevent disease by enabling health-supportive OUTLINE environments ENVIRONMENTAL HEALTH ○​ Unlike the clinical approach, which aims to improve A.​ Definition the health of someone with a disease, environmental a.​ World Health Organization health aims to prevent adverse health outcomes by b.​ American Public Health Association B.​ Environmental Factors and Health Outcomes assessing and intercepting external hazards or risks a.​ Sources of Adverse Health Effects ○​ Health-supportive environments or countries have b.​ Environmental Exposures advanced deployment of control measures and can C.​ Burden of Disease come up with policies that aim to improve human a.​ Global Picture health through different approaches to environmental b.​ Greater Burden of Disease health c.​ Sustainable Development Goals D.​ Diseases, Injuries and Key Environmental AMERICAN PUBLIC HEALTH ASSOCIATION Interventions a.​ Infectious and Parasitic Diseases ​ The branch of public health that: b.​ Neonatal and Nutritional Conditions ○​ Focuses on the relationships between people and c.​ Noncommunicable Diseases their physical environments d.​ Risk Factors for NCDs ○​ Promotes human health and well-being e.​ Unintentional Injuries ○​ Fosters healthy and safe communities f.​ Intentional Injuries E.​ Causality Between Health Outcomes and ​ A key part of any comprehensive public health system Environmental Factors ○​ Everyone is exposed to physical, biological, and a.​ Difficulties in Establishing Causality chemical factors present in the environment, which b.​ Exposure-Response Paradigm may ultimately affect us all, and some may cause F.​ Specific Environmental Health Threats adverse effects a.​ Water Quality i.​ Water and Health ENVIRONMENTAL FACTORS AND HEALTH OUTCOMES ii.​ Examples iii.​ Health Impact ​ Two main focuses of environmental health: iv.​ Water-related Diseases ○​ Factors/hazards/pathogens b.​ Sanitation and Hygiene ​ e.g., pollutants in air, water, soil, or food i.​ Wastewater and Septage Treatment ○​ Transmission ii.​ Barriers ​ How the hazards are introduced to an individual iii.​ Health Aspects ​ e.g., inhalation, ingestion, absorption, vertical c.​ Air Quality transmission, etc. i.​ Indoor Air Pollution ii.​ Health Effects ​ Exposure to different factors or pathogens through d.​ Waste Management different modes of transmission can lead to a wide range i.​ Types of Wastes of adverse health effects ii.​ Public Health Significance e.​ Global Environmental Change f.​ Climate Change and Health i.​ Global Climate Change ii.​ The Philippines and Climate Change iii.​ Health Effects OCCUPATIONAL HEALTH G.​ Definition a.​ Work and Health b.​ Hazard, Exposure, Risk H.​ Action Points a.​ Environmental Intervention Models b.​ Communication and Public Awareness c.​ Education d.​ Advocacy and Public Policy e.​ Research f.​ Improving the Environment to Improve Health Figure 1. Conceptual framework for the determinants of health and wellbeing I.​ References (Barton & Grant, 2006) J.​ Review Questions ​ Figure 1 shows an illustration of the relationship between health outcomes and environmental factors ENVIRONMENTAL HEALTH ○​ Health status is greatly influenced by environmental DEFINITION factors. WORLD HEALTH ORGANIZATION Table 1. Determinants of health outside a population (BSPH 2025). ​ The aspect of public health which addresses all physical, DETERMINANTS OF HEALTH OUTSIDE A POPULATION chemical, and biological factors external to an individual ​ Social determinants of health and all related factors impacting behaviors. Lifestyle ​ e.g., diet, physical activity, work-life ​ Encompasses the assessment and control of those balance environmental factors that can potentially affect health ​ Culture affects way of living Community ​ e.g., traditional practices can affect #MagkabigkisBenteSais Team 01 | 1 of 11  health-seeking behaviors and food ​ Southeast Asia listed the highest mortality from consumption pattern environmental factors ​ Financial factor ​ The Eastern Mediterranean Region exhibited the lowest Local Economy ​ e.g., health-seeking behavior is burden influenced by the capacity to pay ​ Most deaths due to modifiable environmental factors ​ Most activities are limited by physical were preventable space, financial capacity, and cultural ​ It is difficult to pinpoint specific causes of morbidity Activities practices ​ e.g., moving, working ​ Infrastructure or vehicles that can Built affect health Environment ​ e.g., vehicles and factories release CO2 → health suffers ​ Limited to small parks in urban Natural settings Environment ​ e.g., natural habitats, trees, parks ​ Combination of different natural and built environment across the globe Global ○​ Affects activities and lifestyle Ecosystem Figure 3. Fraction of disease burden attributable to the environment by country ​ Dictates climate stability and state of biodiversity ​ Low-income countries have high disease burden from environmental factors ENVIRONMENTAL EXPOSURES ​ High-income countries have lower disease burden ​ Environmental exposures are: ○​ Have policies and guidelines towards improving public ○​ Not genetic health through environmental health approaches ​ Most cannot be passed from one generation to another GREATER BURDEN OF DISEASE ​ Exception: Garbage ​ Greater burden of disease are experienced by: ​ “Our garbage now will still be the garbage of our ○​ Children children.” ​ Still developing ○​ Pollution as opposed to lifestyle ​ Prone to picking up more pollutants ​ Still consider lifestyle in terms of studying how the ​ Weak immune system physical environment affects our behaviors ○​ People with low socioeconomic status ○​ Passive as opposed to active ​ Poor living conditions and sanitation ​ Exposures are just around us, we just ​ Inadequate access to healthcare facilities or inadvertently take them in professionals ​ “We don’t choose to breathe in polluted air but have to since we need to breathe to live.” SUSTAINABLE DEVELOPMENT GOALS ○​ External as opposed to internal ​ Different factors from the external environment acting upon us ​ Ambient environment acts on the general population ​ Occupational environment focuses on the working population ○​ Why is it important to learn about the occupational environment as students? We need to be aware of potential hazards in the workplace setting that may lead to adverse health outcomes and what to do about them. BURDEN OF DISEASE GLOBAL PICTURE Figure 4. Sustainable Development Goal 3 ​ Environmental and occupational health mostly center around SDG 3 (Good health and well-being) DISEASES, INJURIES, AND KEY ENVIRONMENTAL INTERVENTIONS ​ Historically, diseases with the largest absolute burden from environmental exposure include: ○​ Diarrhea ​ Pathogen may be found in poor-quality water ○​ Malaria ​ Mosquito vectors grow in still water Figure 2. Global picture of environmental impact on health ○​ Lower respiratory infections ​ Caused by pollutants in the air and other ​ 24% of global deaths are linked to environmental factors environmental factors ○​ ~13.7 million deaths per year PH 136 | 01_Introduction to Environmental and Occupational Health 2 of 11 ​ Burden is currently dominated by non-communicable land-use planning diseases Management of ○​ Cardiovascular disease has the highest morbidity and Self-harm 8 million 21% chemicals, access to mortality firearms ​ Global estimates are likely to be conservative ○​ Possibility of underreporting due to lack of coverage INFECTIOUS AND PARASITIC DISEASES Table 2. Diseases with the highest preventable disease burden from Table 3. Infectious and Parasitic Diseases. environmental risks, in disability-adjusted life years (DALYs). DISEASES WITH THE HIGHEST PREVENTABLE DISEASE BURDEN PROPORTION MAIN AREAS OF ATTRIBUTABLE DISEASE DALYS ENVIRONMENTAL TO ACTION ENVIRONMENT Household and Lower ambient air pollution, Respiratory 52 million 35% secondhand tobacco Infections smoke Water, sanitation, Diarrhoeal 57 million 57% hygiene, and Diseases agricultural practices NEONATAL AND NUTRITIONAL CONDITIONS Environmental management to Table 4. Neonatal and Nutritional Conditions. reduce vector Malaria 23 million 42% proliferation and contact between vectors and humans Air pollution, NONCOMMUNICABLE DISEASES mothers' exposure to Table 5. Noncommunicable Diseases. Neonatal secondhand tobacco 26 million 11% Conditions smoke, water, and sanitation in birth settings Air pollution, management of Cancers 49 million 20% chemicals, radiation, and workers' protection Unipolar Occupational stress, Depressive 8 million 11% work-life imbalance Disorder Household and ambient air pollution, Cardiovascular 119 million 31% second-hand Diseases tobacco smoke, RISK FACTORS FOR NCDS chemicals Table 6. Risk Factors for NCDs. Chronic Household air Obstructive 32 million 35% pollution, workers' Pulmonary protection Disease UNINTENTIONAL INJURIES Air pollution, Table 7. Unintentional Injuries. second-hand tobacco smoke, Asthma 11 million 44% indoor mold and dampness, occupational asthmagens Occupational stressors, poor work Musculoskeletal postures, prolonged 23 million 22% INTENTIONAL INJURIES Diseases sitting, carrying water Table 8. Intentional Injuries. and solid fuels for household needs Unintentional Injuries (Other Home, community, 74 million 50% than Road and work safety Traffic) CAUSALITY BETWEEN HEALTH OUTCOMES AND Road design, traffic ENVIRONMENTAL FACTORS Road Traffic ​ 31 million 39% system Injuries DIFFICULTIES IN ESTABLISHING CAUSALITY environments, ​ Health may be affected in the long term PH 136 | 01_Introduction to Environmental and Occupational Health 3 of 11  ○​ Signs and symptoms of a disease may not show up ​ DOH provided tablets to disinfect water in the immediately, but over a long course of exposure national penitentiary ​ Particular population groups may be more vulnerable Water-Related Diseases ○​ e.g., children and people living below the poverty line ​ Water-borne ​ Health effects may vary with the season and time of ○​ Via contaminated drinking water day ○​ Mostly enteric (develops in gastrointestinal area) ○​ Different seasons may bring forth different diseases ○​ e.g., diarrhea ​ Rainy season - Waterborne and Vector-borne ​ Water-washed (water-scarce) diseases ○​ Due to lack of proper sanitation and hygiene ​ Dry season - Diseases related to high temperature ○​ Exist due to the limited supply of water (cardiovascular diseases) ○​ e.g., fungal diseases, ophthalmic diseases, infections, ​ While some health effects may be localized, other scabies, louse-borne typhus effects may be community-based, citywide, national, or ​ Water-based even transnational ○​ Caused mainly by parasites that spend most of their ○​ e.g., Burden of air pollution cannot be confined to one life cycles in water area and may be passed around different neighboring ○​ e.g., schistosomiasis areas ​ Water-vectored (water-related) ○​ Insects or vectors that feed or live in water bodies EXPOSURE-RESPONSE PARADIGM ○​ Attributed to still water or standing water ○​ e.g., malaria, dengue fever SANITATION AND HYGIENE ​ 32% of the world’s population has no access to improved sanitation facilities ​ 946 million people still defecate in the open Figure 5. Exposure-Response Paradigm. ​ 64% in Sub-Saharan Africa and 63% in South Asia do not have adequate sanitation facilities Table 9. Exposure-Response Paradigm Example. ​ Out of 2.6 billion people with no access to sanitation EXPOSURE-RESPONSE PARADIGM EXAMPLE services, 75% live in Asia HAZARDS Water with E. coli ​ Greater burden of disease for those living below the EXPOSURE PATHWAY Ingestion poverty line DOSE-RESPONSE Depends on immune system Wastewater and Septage Treatment Severity depends on the strength of ​ In high-income or developed countries, nearly all human HEALTH EFFECTS immune system vs pathogen wastes are collected safely in sewerage systems or septic tanks SPECIFIC ENVIRONMENTAL THREATS ​ In low-income or developing countries: WATER QUALITY ○​ In Latin America and the Caribbean, around 14% ​ Water has a great influence on human health. ○​ In Asia, 34% coverage of wastewater treatment ○​ The body needs water to survive and to perform our ○​ In Africa, there is practically no treatment at all daily activities. Important Barriers to Improving Sanitation ​ Inadequate and poorly used resources Quality of Water ○​ Due to gaps in infrastructure or human resources, we ​ Microbiological Quality of Water cannot fulfill the guidelines ○​ Depending on the agents present, outbreaks or ​ Inappropriate approaches epidemics can occur if there are no interventions set in ○​ Lack of knowledge of wastewater treatment and place. sanitation ​ Chemical Quality of Water ​ Low importance given to women and children ○​ Philippine National Standards for Drinking Water ○​ In a conventional setting, mothers usually act upon details the legally permitted parameters for chemical household decisions qualities of water, such as turbidity and pH levels. Health Aspects of Sanitation ○​ Depending on the quality of the water, acute health ​ The problem of fecal-oral transmission through water effects can be encountered. resources is still big ​ Generally of lower importance ​ Diseases related to fecal-oral transmission: ○​ Example: Arsenicosis in Bangladesh ○​ Cholera ​ Their sources of water were heavily contaminated ○​ Typhoid Fever with bacteria: ○​ Paratyphoid Fever ​ Government of Bangladesh standard was ○​ Salmonellosis higher than the WHO guideline limit (50 μg/L ○​ Shigellosis compared to 10 μg/L) ○​ Giardiasis ​ The government installed tube wells (poso), and ○​ Hepatitis while there was a decrease in diarrheal diseases, ​ 842,000 deaths from diarrheal diseases each year could these tube wells contained high arsenic levels. be prevented by improved water, sanitation, and ○​ Diarrhea is a major public health concern and is hygiene(WHO,2015) mainly caused by unsafe water and poor sanitation. ​ Example: Diarrhea outbreak in Bilibid prison AIR QUALITY ​ Drinking water from a deep well ​ 9 out of 10 people worldwide breathe polluted air (WHO, May ​ 1,212 inmates affected 2018) ​ 2 inmates died PH 136 | 01_Introduction to Environmental and Occupational Health 4 of 11 ​ Indoor Air Pollution (IAP) GLOBAL ENVIRONMENTAL CHANGE ○​ 80-90% of our lifetime will be spent in an indoor ​ Various other environmental changes are now occurring setting: it is one of the most significant environmental worldwide hazards that we face today ​ These large-scale environmental changes do not ○​ Indoor air pollutants tend to aggregate in a small or necessarily pose qualitatively new risks to health enclosed area which makes us more susceptible to ​ Rather, they amplify and extend the health risks posed inhalation of large quantities of pollutants. by many existing environmental hazards ○​ Indoor air pollutants pose potential health risks ​ Examples of existing environmental hazards include: ○​ Indoor air quality problems are strikingly different ○​ Extreme weather events between developed and developing nations ○​ Thermal stress ○​ Food and water shortages ○​ Toxic Persistent Organic Pollutants (POPs) ​ Melting Arctic ice is forcing polar bears to swim for more than a week without rest (Kaplan, 2016) via The Washington Post From BSPH 2024 Trans: ​ Polar bears are apex predators ​ Ecosystems need predators to maintain balance ​ Loss of polar bears can disrupt the amount of fish and aquatic products to which the communities are dependent for food and livelihood ​ Ultimately leading to food security and safety problems ​ Link is hard to establish but implications in health are evidently present CLIMATE CHANGE AND HEALTH Figure 6. Indoor Air Pollution Risks at Home Global Climate Change Health Effects ​ Increase in human-induced Greenhouse Gas (GHG) ​ Chronic bronchitis: adults who have occupational hazards emissions → Alteration of the lower atmosphere → Change (biomass users) in world climate ​ Lung cancer: developed over time (coal users) ○​ This has widespread consequences for human ​ Children are susceptible to: health ○​ Lower respiratory tract illnesses ○​ Allergic effects such as rhinitis, sneezing, and eye irritation WASTE MANAGEMENT ​ Types of Wastes ○​ Solid wastes ○​ Liquid wastes ○​ Gaseous wastes ○​ Healthcare wastes Figure 8. Climate Change and Vulnerability Mapping for SEA, 2009 The Philippines and Climate Change ​ Temperature spikes and warming in certain parts of the country ○​ Regions with high-temperature spikes experienced drought ○​ Example: Province of Isabela in Cagayan Valley ​ Drought came to the province in December, 2009 ​ PAGASA said it was brought about by El Niño Figure 7. Waste Management Pyramid ​ Estimated corn production loss of Php 1.8 billion ​ Precipitation trends are largest during the 20th century ​ Public Health Significance (PTFCC, 2007 in IHPDS NIH-UPM, 2011) ○​ Aesthetic Issues ​ Since the 1980s, extreme weather events have occurred ​ Creates eyesores and unpleasant odors more frequently. ○​ Infrastructure Problems Health Effects ​ Leads to clogging of sewers, drains, and rivers ○​ Health Hazards ​ Heat stroke ​ Serves as breeding grounds for insects and ​ Drowning, dehydration, diarrheal disease, psychological rodents trauma ○​ Water Pollution ​ Malnutrition, growth retardation, and developmental delay ​ Contaminates surface and groundwater sources. ​ Malaria, dengue fever, and other vector-borne diseases ○​ Air Pollution Contribution ​ Adds to air quality degradation. PH 136 | 01_Introduction to Environmental and Occupational Health 5 of 11  OCCUPATIONAL HEALTH DEFINITION(WHO, ILO, 1995) ​ Promotion and maintenance of the highest degree of physical, mental, and social well-being of workers in all occupations by: ○​ preventing departures from health ○​ controlling risks ○​ adapting work to people and people to their jobs ​ Examples: ○​ Training (onboarding sessions and pre-employment training) Figure 10. Environmental Intervention Models ○​ Administrative changes (work-from-home set-up) ​ In its broadest sense, it should aim at the following: COMMUNICATION AND PUBLIC AWARENESS ○​ The prevention among workers of adverse effects on ​ Informs people of all ages and functions health caused by their working conditions; ​ Internet resources are powerful mechanisms to facilitate ○​ The protection of workers in their employment from information exchange risks resulting from factors adverse to health; ​ Both formal and informal actions to raise public awareness ○​ The placing and maintenance of workers in an have been successful occupational environment adapted to physical and mental needs; and, EDUCATION ○​ The adaptation of work to humans ​ Actions in the area of education aim to increase the competence of health professionals. WORK AND HEALTH ​ Recognition and management of the health effects ​ Work may have an adverse or beneficial effect on health. ​ Breaking the cycle of exposure, illness, treatment, and ​ The health status of the worker has an impact on work reexposure and productivity. ​ Health professionals are on the front line HAZARD, EXPOSURE, RISK ADVOCACY AND PUBLIC POLICY ​ Hazard: A potential element (object or condition) that can ​ All levels of society can advocate for environmental health cause harm in the workplace and influence policy agendas. ○​ Example: Pollutant, exposed wiring, flickering lights ​ Exposure: Contact with a hazard RESEARCH ○​ Example: Inhalation, ingestion, direct contact ​ Promotion of collaborative research in environmental ​ Risk: The probability of realizing harm due to exposure to a health in developing and developed countries is essential hazard ​ The results of appropriate studies can be used in strategies for prevention, intervention, and remedial action ​ Collaborative activities would also result in technology transfer and capacity building IMPROVING THE ENVIRONMENT TO IMPROVE HEALTH ​ WIN-WIN strategies deemed fundamental to achieving sustainable development goals WIN-WIN Strategies 1.​ Apply low-carbon strategies in energy generation, housing, and the industry. 2.​ Use more active and public transportation. Figure 9. Relationship of hazard, exposure, and risk 3.​ Introduce clean fuels for cooking, heating, and lighting and clean technologies. From BSPH 2024 Trans: 4.​ Reduce occupational exposures and improve working ​ The occurrence of risk is realized if both hazard and conditions. exposure are present. If exposure is absent, yet the hazard 5.​ Increase access to safe water and adequate sanitation is still present, the realized risk is minimal. However, if the hazard is not present, there will be no exposure, and this and promote hand washing. being the case, the risk is not realized 6.​ Change consumption patterns to lower the use of harmful chemicals, minimize waste products, and save ACTION POINTS energy. ​ The aim is to cut the risk of adverse health outcomes 7.​ Implement interventions that can increase sun-protective from the source itself. behavior. ○​ From a healthy population, we try to devise 8.​ Pass smoking bans to reduce exposure to second-hand interventions or approaches that would avoid or tobacco smoke. reduce exposure to environmental pollutants. 9.​ Always use a health in all policies approach to create ​ If this is not done, we can try to employ different healthier environments and prevent disease. interventions to avoid spreading communicable diseases among the population. PH 136 | 01_Introduction to Environmental and Occupational Health 6 of 11  7.​ TRUE OR FALSE. Chemical water quality is generally of higher importance than microbiological water quality due to the time needed to treat it. 8.​ TRUE OR FALSE. All diseases are linked to environmental factors. 9.​ TRUE OR FALSE. The Clinical Intervention Model underscores the importance of striving for and attaining safe environments to keep people safe and healthy. 10.​ Which among the following is NOT part of the WIN-WIN Strategies? a.​ Reduce occupational exposures b.​ Increase access to safe water c.​ Increase sun protective behavior d.​ Ban alcohol consumption ANSWER KEY 1.​ B 7.​ FALSE - Microbiological 2.​ A water quality is of higher 3.​ A importance 4.​ D 8.​ TRUE Figure 11. WHO strategies to improve the environment and our health 5.​ B 9.​ FALSE - Should be the 6.​ C Environmental REFERENCES Intervention Model ​ Lectures 10.​ D Cube, F. A. B. (2025). Introduction to Environmental and Occupational Health. REVIEW QUESTIONS (BSPH 2025) 1.​ Which of the following are barriers to progress in sanitation? a.​ Inappropriate approaches b.​ Low importance given to women and the elderly c.​ Inadequacy of resources d.​ Poor usage of resources 2.​ In developing countries, the percentage of wastewater treated is low. Indoor Air Pollution (IAP) pertains to ambient air pollution. a.​ The first statement is correct and the second statement is incorrect. b.​ The first statement is incorrect and the second is correct. c.​ Both statements are correct. d.​ Both statements are incorrect. 3.​ TRUE OR FALSE. Large-scale environmental changes do not necessarily pose qualitatively new risks to health. a.​ True b.​ False 4.​ Which of the following does not characterize environmental exposures? a.​ Not genetic b.​ External c.​ Passive and involuntary d.​ Lifestyle 5.​ WHO defines environmental health as the key part of any comprehensive public health system. It is easier to associate diseases with causative agents than the environment. a.​ The first statement is correct and the second statement is incorrect. b.​ The first statement is incorrect and the second is correct. c.​ Both statements are correct. d.​ Both statements are incorrect. 6.​ The following are diseases with the largest absolute burden from environmental exposure except: a.​ Diarrhea b.​ Malaria c.​ Heart Disease d.​ Lower Respiratory Infections PH 136 | 01_Introduction to Environmental and Occupational Health 7 of 11  APPENDICES Figure 1. Conceptual Framework for the determinants of health and wellbeing Figure 2. Global picture of environmental impact on health Figure 3. Fraction of disease burden attributable to the environment by country PH 136 | 01_Introduction to Environmental and Occupational Health 8 of 11  Figure 4. Sustainable Development Goal 3 Table 3. Infectious and Parasitic Diseases. Table 4. Neonatal and Nutritional Conditions. PH 136 | 01_Introduction to Environmental and Occupational Health 9 of 11 Table 5. Noncommunicable Diseases. Table 6. Unintentional Injuries. Table 7. Intentional Injuries. PH 136 | 01_Introduction to Environmental and Occupational Health 10 of 11  Figure 6. Indoor Air Pollution Risks at Home Figure 8. Climate Change and Vulnerability Mapping for SEA, 2009 Figure 11. WHO strategies to improve the environment and our health PH 136 | 01_Introduction to Environmental and Occupational Health 11 of 11