PHWM 2110 Public Health Ecology Exam #1
toxicology
the study of poison; anything can be poison (Paracelsus)
what is the goal of exposure assessment?
to quantitatively and qualitatively describe agent's contact and entry into body
what is an example of an area source?
urban run-off
environment interacts with
a person's genetic make up
uptake
absorption through skin or inhalation or ingestion
how much time do americans spend indoors?
we spend about 90-95% of our day is indoors
how does a health effect occur?
when both the exposure and intake occur
when does an exposure become a dose?
when it enters the body
Gauley Bridge Disaster
problem: workers were exposed to high levels of silica causing health problems; occupational diseases law: broadened the Workmens' Compensation to include occupational disease and injury
what is a secondary source?
produced in the environmental media through condensation (ex: ozone)
Thomas Malthus
started conversation about population growth and decline, proposed idea about populations growing until resources have been exhausted
transport and fate
study of how chemicals degrade and wheeree chemicals travel in the environment when they are released intentionally or unintentionally
toxciologists
study poison (any substance that causes a harmful effect to living organisms)
applied dose
subset of potential dose that refers to the amount that has made contact with skin, digestive tract, or respiratory tract where absorption into bloodstream can occur
aggregate exposure
sum of all exposures of an organism to a single chemical pathway over a period of time
Rachel Carson
the modern day environmental movement
OSHA
occupational safety health association
policy development in public health
- inform, educate, empower - mobilize community partnerships -develop policies
emissions
- measured as a rate; amount of contaminant per unit of time
personal exposure concentrations
- measures concentrations near the person - Personal exposure measurements for VOCs (volatile organic contaminants) are usually more closely correlated with indoor measurements than outdoor measurements.
assessment in public health
- monitor health - diagnose and investigate
instantaneous exposure
- occurs in a single measurable point in time
assurance
- Evaluating effectiveness, accessibility, and quality of personal and population-based environmental public health services - Addressing the sufficiency of a competent environmental public health workforce
Workplaces are often preferred as a "laboratory" for the study of general environmental health effects because they typically feature:
- Higher exposures - Fewer confounder influences - Better estimation of exposure intensity - A more clearly defined study population
obesity in the United States
- Prevalence is increasing in all age groups. - Obesity prevalence is growing at a much faster rate in the youngest age groups. - Over 60% of the US population meets the definition of overweight. - One in three Americans meets the definition of obesity.
urban sprawl has been indirectly or directly accelerated by
- The GI Bill which resulted in insured mortgages and a decrease in mortgage interest rates. - The Taxpayer Relief Act of 1997 that allows individuals to exclude up to $250,000 of capital gains on the sale of a residence. - Increased highway construction. - Federal tax laws allowing mortgage interest to be tax deductible.
exposure concentration
- amount of toxic agent - amount of contaminant in the environmental media that contacts the body
response
- biological change(s) caused by a chemical, physical, or biological agent - biological change can be occur at cellular, molecular, or tissue level
disruptions of endocrine system
- chemicals in everyday products interfere with endocrine system and production of hormones (pharmeceuticals, dioxins, polychlorinated biphenyls PCBs, DDT pesticides, bisephnol A) - health problems (early onset of puberty in girls and other development problems; obesity)
things to consider when examining exposure
- concentration in contact media - sociodemographic of the receptor (ex: children and elderly are more susceptible to exposures than adults) - behavioral factors (ex: if individual smokes it could increase degree to which exposure becomes toxic) - physiologic factors, health status (ex: those that are immunocompromised may be more susceptible to certain exposures than people that are health)
exposure
- contact over time of one or more biological, chemical, or physical agents with the outer part of the human body (skin, mouth or nose) at a specific concentration for a specific interval of timee - exposure always occurs first but not all exposures result in adverse effects
cumulative exposure
- cumulated dose of exposure during a certain time period - sum total of all exposures to all chemicals over all pathways (inhalation, ingestion, dermally)
environmental health
- defined by the problems faced - uses a systems approach to understand a problem; usually focuses on populations - includes any aspect of the environment (housing, agriculture, urban development, transportation)
Paracelsus
- father of toxicology - dose-response relationship - when considering the potential adverse effects of a given toxicant, the exposure intensity is a critical determinant
biologically effective dose
- fraction of delivered dose that is capable of producing a toxic effect - whether or not the biologically effective dose will cause an effect will depend on the body's ability to defend or repair itself to detoxify the agent
built environment has been associated with
- increased prevalence of several chronic diseases, notably asthma, obesity, cardiovascular disease and depression - The built environment can also favor social equity or increase disparities
exposure pathway
- physical course followed by an agent as it moves from source to human - course of path along which a contaminant moves from its source to an ecological of human receptor (individual or population)
source
- point of origin of a toxic agent - properties, amount released/used, location/setting
muckrakers
- writers who were bringing attention to horrible working conditions of the Industrial Revolution - these persons or groups contributed through their writings to increasing public awareness of the poor working conditions of certain groups of U.S. workers
elements of exposure pathway to be complete
1. source - origin of contaminant 2. environmental media - soil, water, air, food, etc. through which a contaminant moves from its source 3. exposure or point of contact - where and how people contact the media 4. exposure route - how the material can potentially enter the body 5. receptor - individual or population who are exposed or potentially exposed
accident and safety phase
1890s, workers experienced disease and injuries, workers compensation programs
occupational disease phase
1920s, occupationally related diseases came into the picture and was added to compensation programs
health conversation phase
1940s, medical examinations and surveillance of injuries were done by employers to converse worker health
OSHA/EPA phase
1970s, Occupational Safety and Health Act of 1970 (Williams-Steigler Act) ensured employers were providing safe working environments for employs, National Institute of OSH was created, also EPA.
health promotion wellness phase
1980s, smoking and drugs, workplace-based health promotion programs
ADA phase
1990s, Americans with Disabilities act, making workplaces and public spaces accessible for disabled persons
secruity phase
2000s, safe work environment took on another meaning with the 9-11 terrorist attack, public health preparedness and response to bioterrorism; expansion of the field to include public health preparedness and response to terrorist attacks
indoor pollution affects _____ children
6.2 million; asthma prevalence is increasing even though outdoor air quality if improving
ADA
Americans with Disabilities Act
direct exposure
Contact with a chemical substance that occurs while using it or by being present in an area where it has been used (Ex: child eating lead chips
policy development
Empowering people about environmental public health issues
assessment
Investigating environmental public health problems and health hazards in the community
what are the phases of occupational health and safety in the United States?
accident and safety phase (injury), occupational disease phase (illness), health conversation phase, OSHA/EPA phase, health promotion wellness phase, ADA phase, security phase
response and time
acute (short term), chronic, delayed onset (latency), reversible, irreversible, age dependent, specific, nonspecific
natural environment
air, water, soil, chemical, biological, and social features of our surroundings
internal dose
amount of agent that crosses absorption barriers and is metabolized by the body
dose
amount of something we ingest (can be eaten, inhaled or absorbed; amount of agent actually deposited at one or more sites within the body
potential dose
amount of toxin taken in that is inhaled, ingested, or absorbed through skin
delivered dose
amount that reaches the target organ
3 core functions of public health
assessment, public policy development, and assurance
in the EHP, what does the triangle depict?
barrier between the inside of the body and the outside
man-made, or built environment
buildings, roads, transportation systems, land use, pollution, and waste management
what is an example of a mobile source?
car
indoor microenvironmental monitor
cart loaded with sampling devices measures concentrations in a room or home
many environmental health problems are born out of
crisis which leads to the creation of laws
average exposure
cumulative divided by total duration of exposure
risk management
determination of source and level of health risks that are acceptable and how to manage
what is the goal of effect assessment?
determine intrinsic hazards association with hazard and quantify relationship between dose and health effect (hazard identification)
dose-response relationship
diagram displaying relationship between dosage and response
social environment
diet, exercise, socioeconomic status, and other societal influences
route of exposure
different ways an agent can enter the body (inhalation, ingestion, or dermally)
intake
entry of the substance into the body
climate change affects health
environmental effects (weather changes, ecosystems, water scarcity/flooding, oceans, air quality) and disease concerns (food/water borne illnesses, asthma, cancer, infectious disease carried by animals)
EPA
environmental protection agency
risk assessment
estimates the likelihood, magnitude, and uncertainty of population health risks associated with exposures
secondary pathway
ex: lead paint that has contaminated soil and soil is ingested or inhaled
what is the exposure formula?
exposure = intensity x frequency x duration ...or... how much? x how often? x for how long?
mixed exposure scenarios
exposure to more than one toxic agent during a given time
what is an example of a stationary source?
factory or refinery
Agricola
father of mineralogy, mining, and health effects, penned De Re Metallica
Percival Pott
father of occupational epidemiology, connected chimney sweeps to scrotal cancer
Ramazzini
father of occupational medicine, penned Diseases of Workers
peak exposure
highest level of exposure over a given time
what is the natural history of a public issue?
identification -> politicization -> legislation -> litigation
exposure assessment
identify and define exposures occurring or anticipated to occur in the human population
adverse effect
if biologically effective dose harms the body
what are the 10 essential environmental public health services?
monitor health status and solve problems diagnose and investigate problems inform, educate, and empower mobilize communities develop policies enforce laws link people to services assure competent workforce evaluate effectiveness of services research
epidemic of illnnesses
parallel economic development and energy utilization
industrial revolution
periods of time in both the U.S. and Europe, was characterized by increased wealth, prosperity and productivity, but also by an increase in the number of work-related injuries and exposure to physical agents
in the environmental health paradigm, what is the continuum between origin of toxic agent and its effect on humans?
pollutant source -> environmental fate and transport -> exposure -> dose -> effect
which groups are more suspectible to environmental agents?
poor and minority populations, children, and the elderly
Bhopal Disaster
problem: Union Carbide plant in India leaked chemicals killing many; industrial and transport disasters law: led to the hazard communication/Community Right to Know Laws
Farmington, W. Va., Coal Mine Disaster
problem: coal mine disaster, black lung disease; occupational injuries and dieasese law: Coal Mine Health and Safety Act of 1968 and 1970
Triangle Shirtwaist Co. Fire
problem: fire broke out and led to many injuries and deaths; occupational injuries and fire hazards law: resulted in the State Workmens' Compensation in Wisconsin and New Jersey
world war II
protection of health at the workplace
personal monitoring
provides more accurate information on individual exposures to airborne contaminants
environmental health paradigm describes
relationship between a toxicant and its effect on health by identifying and characterizing a complex pathway that begins with the emission source of that toxicant and ends with the response of the host to the effects of that toxicant
what is an example of a point source?
smoke stack
examples of indoor, non-seasonal allegerns
smoke, cockroaches, dust mites, mold, pet dander, and pollen