Environmental Risk: Threats and Solutions

• Environmental Risk refers to the vulnerability of ecosystems, natural resources, and biodiversity to harm from human activities and natural phenomena.

Protecting Our Environment: Progress & Challenges

• Monitoring outdoor air and water quality are key
• Effectively handling toxics and waste is essential
• Promoting healthy homes and communities is a priority
• Maintaining infrastructure and surveillance is needed
• Addressing global environmental health issues is critical

Environmental Stressors

• Physical factors include climate, indoor microclimate, ionizing and non-ionizing radiation, solar radiation, noise, and vibration
• Chemical factors can have acute, chronic, specific, delayed, and transplacental effects.
• Biological factors include microorganisms, fungi, cyanobacteria, algae, their toxins, plants, insects, and animals.

Environmental Risk Transition

• Characterizing changes in environmental risks as a consequence of economic development is important, especially in less developed regions

Viruses

• H5N1 Virus causes avian influenza
• H1N1 Virus causes swine flu

The 3 P's

• Pollution
• Population
• Poverty

Population Dynamics

• Ever-changing interrelationships among variables influence the demographic makeup and size of populations

Population Variables

• Fertility: Total fertility rate is the average number of children born to a woman over her lifetime
• Death rates/Mortality
• Migration

Effects of Rapid Population Growth

• Urbanization
• Overtaxing carrying capacity
• Food insecurity
• Loss of biodiversity

Carrying Capacity

• Maximum number of individuals that can be sustainably supported by a given environment

Food Insecurity and Famine

• Can occur when the carrying capacity in a particular geographic area is exceeded

Environmental Control Professionals

• Hygienists control hazards affecting workers and the community
• Toxicologists study the impact of chemical, biological, and physical agents on living organisms. They work in academia, government, hospitals, and private industry
• Environmental Health Inspectors monitor and enforce environmental regulations
• Food Inspectors/Food Safety Specialists ensure the cleanliness and safety of food and beverages for the public
• Vector Control Specialists enforce public health laws and regulations related to the spread of disease by vectors
• Researchers/Research Analysts conduct research on risks associated with specific hazards

Occupational Health

• Occupational Health Physicians focus on preventing and treating occupationally related illnesses and injuries
• Environmental Lawyers provide input to government agencies, assist in formulating environmental policies, and handle litigation related to environmental health problems

Environmental Epidemiology

• Studying how chemical, biological, and physical environmental exposures impact human health
• Identifying cause-and-effect relationships between environmental hazards and diseases

The Environment Defined

• All non-genetic factors outside the human genome
• Exogenous factors affecting human beings and altering disease and health patterns

Epidemiology Defined

• Study of the distribution and determinants of health, diseases, morbidity, injuries, disability, and mortality in populations.

Common Environmental Health Factors

• Chemicals like dust, drugs, tobacco, and foods
• Accidents involving hazards, speed, and alcohol
• Psychological factors like stress, work patterns, and human relationships
• Biological agents such as bacteria, viruses, and parasites
• Physical factors including noise, climate, lighting, and radiation

Research Topics for Environmental Epidemiology

• Air pollution
• Chemicals
• Climate Change
• Water Pollution

Contributions of Epidemiology to Environmental Health

• Focuses on populations, studying the entire population, making it population medicine
• Relies on observational data
• Uses specific methodologies for study designs
• Includes descriptive and analytic studies

Epidemiological Field Investigation

• Descriptive epidemiology involves defining the illness, considering hypotheses and biological significance, defining the population at risk, measuring the disease, and establishing surveillance
• No action is indicated if there is no significant disease excess

Analytical Epidemiology

• Starts with stating a hypothesis and designing a study that considers design, sample size, illnesses, exposures, confounding factors, ethics, and resources
• Requires performing the study
• May involve intervention to remove or modify suspected causes and re-evaluate it
• Often involves further studies with collaborating agencies and working groups

Pioneers of Environmental Epidemiology

• Hippocrates (c. 460 BC): Ancient Greek physician, known as the "father of medicine". Expounded on the role of environmental factors like water quality and air in causing diseases
• Sir Percival Pott: Significant London surgeon; the first to describe an environmental cause of cancer, linking scrotal cancer to soot in chimney sweeps
• John Snow: English anesthesiologist who linked a cholera outbreak in London to contaminated water from the Thames River during the mid-1800s

Epidemiologic Triad/Epidemiological Triangle

• Serves as a tool to frame and identify risk factors
• Adverse health effects depend on the interaction of host, environment and agent
• This interaction is determined by the hazard, exposure and response

Environmental Toxicology

• A multidisciplinary field studying harmful effects of chemical, biological, and physical agents on living organisms

Toxicology

• The science of poisons
• Humans are exposed to chemicals both accidentally and intentionally
• Most human exposure comes from naturally occurring compounds consumed from food plants

Sources and Types of Environmental Toxicants

• Natural Sources: heavy metals and mycotoxins from fungi
• Anthropogenic Sources: industrial waste, agricultural pesticides/herbicides, air pollutants, pharmaceuticals, and personal care products (PPCPs) in wastewater

Poisonous Substances

• Produced by plants, animals, or bacteria
• E.g., Pythotoxins, zootoxins, and bacteriotoxins

Xenobiotics

• Man-made or produced substances not normally found in the body, like synthetic chemicals
• Only poisons are xenobiotics
• Examples: drugs, food additives, hydrocarbons, environmental pollutants, synthetic polymers, pesticides, and oil mixtures

How the Body Handles Xenobiotics

• Redistribution
• Excretion: Metabolic waste elimination via kidneys, liver, skin, and lungs
• Metabolism: All chemical processes for life and normal function

Toxicology Terms

• Toxicants: Any substance, chemical or physical, causing adverse biological effects
• Toxins: Specific proteins produced by living organisms, like mushroom or tetanus toxin
• Poison: Toxicants causing immediate death or illness in small amounts
• Dose: Measured quantity of medicine, nutrient, or pathogen; larger doses have larger effects
• Exposure: Contact providing opportunity to obtain poisonous dose
• Hazard: Source/situation with potential for harm to human health, property, or the environment

Historical Toxicology

• 700 B.C.: Chinese journals documented plant and fish poisons
• 800 B.C.: Hindu medicine includes notes on poisons
• 50-100 A.D.: Greek physicians classified over 600 poisons (plant,animal and mineral types)
• Swiss physician Paracelsus (1493-1541) is considered "the father of modern toxicology" for his insights on dosage
• Italian physician Ramazzini (1713) described "asthma" in various professions

Exposure Concepts

• Different toxic responses are rooted in routes, frequency, and duration of exposure (acute vs. chronic)

Exposure Routes

• Ingestion (water and food)
• Absorption (through skin)
• Injection (puncture or cut)
• Inhalation (air)

Exposure Sources

• Environmental, occupational, therapeutic, dietary, accidental and deliberate

Duration & Frequency of Exposure

• Repeated exposures:
• acute (less than 24 hours)
• subacute (up to 30 days)
• subchronic (30-90 days)
• chronic (over 90 days

Philippine Environmental Laws include:

• RA 9512: Environmental Awareness and Education Act of 2008
• Presidential Decree No. 1586: Environmental Impact Statement System
• RA 9275: The Philippine Clean Water Act of 2004
• RA 8749: The Philippine Clean Air Act of 1999
• RA 9003: Ecological Solid Waste Management Act of 2000
• RA 6969: Toxic Substances and Hazardous and Nuclear Waste Control Act of 1990

RA 9512: Environmental Awareness and Education Act of 2008 approved in December 2008, promotes environmental awareness

• Environmental education promotes awareness, knowledge, positive attitudes, skills, and participation for environmental protection

Presidential Decree No. 1586: Environmental Impact Statement System

• Aims to balance economic growth and environmental protection

The Philippine Environmental Impact Statement (EIS) System Laws

• PD 1152 (1977) - Philippine Environment Code
• PD 1586 (1978) - EIS System

Environmental Impact Assessment (EIA)

• Predict the environmental effects of a project to design mitigating and enhancement measures

Environmental Compliance Certificate (ECC)

• Document by DENR/EMB certifying proposed projects will not cause significant negative environmental impact

Certificate of Non-Coverage

• Issued by EMB when projects are not covered by the EIS System

Environmental Critical Projects

• Pose a high potential for significant negative environmental impact

Environmental Critical Area

• Environmentally sensitive areas where significant environmental impacts are expected from certain projects

Environmental Impact Statement (EIS)

• A comprehensive study of the significant impacts of a project on the environment

Initial Environmental Examination

• Document similar to EIS, but with reduced detail

IEE Checklist

• A document similar to IEE set up as a question and answer form

DENR MC NO. 2007-08

• The EIA process is transmitted to government agencies and the issuance of an ECC or CNC

RA 9275 Philippine Clean Water Act of 2004

• Protects the country's water bodies from pollution from land-based sources through comprehensive and integrated strategy

Pollution Discharges

• Agricultural wastewaters
• Domestic sewage
• Industrial effluents

Water Pollution Facts

• 58% of wells tested by EMB-DENR were contaminated with coliform
• 50 rivers are considered biologically dead
• Main contributors of organic water pollutants: domestic (50%), agricultural (35%), industrial wastewaters (15%)

Goals of Water Quality Management

• Based on watershed, river basin or water resources regions
• Localized
• Governing boards to manage water quality issues

Prohibited Acts in CWA

• Depositing material causing water pollution
• Discharging polluting substances into the earth
• Illegal operations
• Refusal rights
• Illegal transfer

Waste Water Discharge Permit Requirements

• Includes engineer reports
• Certificate of Accreditation and previous discharge permits

RA 8749 Philippine Clean Air Act of 1999.

• National program of air pollution management implemented by Government

Stationary sources

• building, immobile structure, or facility emitting air pollutants

Mobile Sources

• Any vehicle or machine propelled by fuel and emitting pollutants

Industrial Sources of Air Pollution

• Must comply with National, and Ambient Regulations

RA 9003 Ecological Solid Waste Management Act of 2000 includes

• Segregation, Transportation, Storage, Transfer, Processing, and Disposal

THE NATIONAL SOLID WASTE MANAGEMENT COMMISSION (NSWMC)

• Overseeing the implementation of SWM
• 17 members
• 3 private sector
• National Ecology Center
• Secretariat

Solid Waste Management

• Solid waste is harmful to the earth due to river, surroundings and water quality.

Objective of The Toxic Substances and Hazardous and Nuclear Wastes Control Act of 1990

• To protect the public and environment from the risk from the misuse of chemicals and hazardous waste
• The generator is responsible until the waste is disposed
• If something goes wrong, the generator is at fault

Poor Waste Management results to:

• Air and water pollution
• Global warming - methane
• Diseases - Rats, Mosquitoes
• Flooding - drains

Hazardous Wastes are

• By products that create a risk to the environment.

The characteristics of the wastes are:

• Toxicity
• Ignitability
• Corrosivity
• Reactivity