Week 1 Flashcards
(23 cards)
Environmental Health Science - 2 key ideas
- broad view of environment
1. goal is to minimise the damage of environmental factors
2. goal is to maximise the benefits of environmental factors
The significant overlap between planetary health and traditional environmental health
Both examine the relationship between human health and conditions and exposures originating outside the body
- extreme temperatures, chemicals and biological agents, vector-borne diseases, or any number of other potential factors
Planetary health
Planetary health is a field of study that examines the interconnections between human health and the planet
Explicitly accounts for the importance of natural systems
- in terms of averted cases of disease and the potential harm that comes from human-caused perturbations of these systems - a consideration that has not necessarily factored into environmental health research to date
The hierarchy of exposure controls (most effective to least effective)
- Elimination - physically remove the hazard
- Substitution - replace the hazard
- Engineering controls - make physical modifications to control the hazard
- Administrative controls - change the way people work
- PPE - protect the worker with personal protective equipment
Where should we intervene to control exposure: at the source, along the exposure pathway, or at the level of the individual
Examples of strategies to reduce exposure to traffic-related air pollution
At the source:
- reduce vehicle miles travelled
- technology (electric vehicles, control technology)
Along the exposure pathway:
- build homes, schools, hospitals farther from roads
At the household or individual:
- use air filters, facemarks
- keep windows and doors closed
Where are hazards first identified? Key to prevention? Are most chronic disease man-made?
- hazards usually identified first in workers and then in communities
- identifying and controlling environmental hazards are key to prevention
- yes, most chronic diseases are man-made
Why study the past?
- to learn how to intervene on new threats from past solutions
- to improve medical care of patients
- to understand trends in burden of disease
- to identify root causes and prevent disease
Stages of Epidemiologic Transition
- The age of pestilence and famine
- The age of receding pandemics
- The age of man-made diseases
Percival Potts 1775
- Pott was the first to link occupational exposure to cancer, identifying a high incidence of scrotal cancer in chimney sweeps caused by prolonged exposure to soot.
- This was one of the earliest connections between environmental hazards and cancer
- His work led to better hygiene practices and eventually influenced public health policies to reduce workplace carcinogen exposure.
Asbestos
- once called “miracle mineral”
- fireproof and indestructible
- In the 1960s, Dr. Irving Selikoff identified and explained the health effects of asbestos exposure - he became the Public Health Crusader
- microscopic asbestos fibres are inhaled or swallowed and settle into the lungs or tissue lining
- It takes an average of 30 years after exposure to asbestos before obvious symptoms appear. Incidents of mesothelioma are projected to continue for up to 30-40 years
John Snow
Joseph Bazalgette
- In 1858, the stench from the Thames was so bad that Members of Parliament refused to use Westminster becuse the smell made them all feel sick.
- The press called the crisis The Great Stink.
- Disraeli introduced a Bill to Parliament which gave Bazalgette the authority to construct the enormous sewer system which he had designed.
Typhoid mortality and water treatment
- The authors estimated that clean water reduced overall mortality by 13%.
- Clean water was responsible for 74% reduction in infant mortality and a 62% reduction in child mortality in these cities during that period and the near eradication of typhoid fever
Epidemiological Triangle - Wade Hampton Frost
- a microbe capable of causing infection and disease
- a host population with sufficient numbers of susceptible people
- conditions in the environment to bring the agent into contact with infectible hosts
Triangle:
Environment (top point)
Agent
Host
Dr. Alton Ocshner
The first anti-smoking crusader
- “lung cancer soon will become more frequent than any other cancer of the body, unless something is done to prevent its increase”
Dr. William Heuper
Dr. Wilhelm (William) Hueper was a pioneering pathologist who linked occupational and environmental exposures—such as industrial chemicals, asbestos, and petroleum products—to cancer, influencing modern workplace safety and cancer prevention efforts.
Dr. Richard Doll
“on average cigarette smokers die about 10 years younger than non-smokers”
Richard Doll was a epidemiologist who, through groundbreaking studies like the British Doctors’ Study, provided definitive evidence linking smoking to lung cancer and other diseases, leading to major public health reforms.
Would it be cost-beneficial to prevent lead exposure?
Absolutely. For every dollar spent to reduce lead hazards in homes, it has been estimated that society would benefit between $17 to 221.
Childhood vaccines, which are among the most cost-effective intervention in public health or medicine, has a cost-benefit ratio of about 1:16. So preventing lead exposure is at least as cost-effective as childhood vaccines.
criteria for causation
- strength of the association
- consistency of the association
- specificity of the association
- temporality
- biological gradient
- plausibility
- coherence
- experiment
- analogy
Alice Hamilton
studied lead poisoning
Herbert Needleman
In the seminal study of the toxicity of low-level lead exposure, Herb Needleman found that lead was associated with behaviors consistent with ADHD.
Marie Curie
- Marie Curie, inspired by Henri Becquerel’s 1896 discovery of radioactivity, conducted research with her husband, Pierre.
- Together, they isolated polonium—named after her birthplace, Poland—and radium.
- She developed methods to extract radium in sufficient quantities for detailed study, particularly its therapeutic applications.
Initially, the Nobel Committee intended to honor only Pierre Curie and Henri Becquerel, but Swedish mathematician Magnus Gösta Mittag-Leffler advocated for Marie’s inclusion.
- As a result, she became the first woman awarded a Nobel Prize.
Curie later won a second Nobel Prize, making her the first person to receive two in different fields (Physics and Chemistry).
- She also coined the term radioactivity and paved the way for advancements in medical and nuclear science.
