Environmental Determinants of Health - Session 1 Flashcards
What are the 4 major classes of infectious agents?
viruses, bacteria, protozoa and helminths
Definition of diarrhea
the pass of 3 or more loose or liquid stools per day
Why can diarrhea be deadly?
water and electrolytes are lost, dehydration occurs, and severe dehydration can lead to death
diarrhea that lasts several hours, and includes cholera
acute watery diarrhea
dysentery
acute bloody diarrhea
diarrhea that last 14 days or longer
persistent diarrhea
Which infectious agent accounts for 85% of all diarrhea deaths worldwide
rotavirus - and there is a vaccine for it!
How is diarrhea treated?
rehydration, zinc supplements, nutrient rich food, and antibiotic treatment
What is an oral rehydration solution?
A mixture of clean water, salt, and sugar
What is the interplay between diarrhea and malnutrition?
It’s more likely to cause death in malnourished children - they can’t invest the nutrients of the little food they are taking in
an acute intestinal infection cause by ingestion of contaminated food or water - has a short incubation period and produces an enterotoxin that causes copious painless watery diarrhea
cholera
What is the lifecycle of cholera?
aquatic reservoir - human host - contaminated food and water
What are the environmental factors that effect cholera outbreaks over time?
plankton levels in the water and the water temperature
How do we treat cholera infections?
oral rehydration solution and itnerevenous fluids with antibiotics
What is the main cause of death with cholera?
dehydration
A microscopic parasite that is the leading cause of diarrheal disease in the US - infects both animals and humans, has an outer shell that makes it tolerant to chlorine disinfectance
cryptosporidium
What is the main symptom of cryptosporidium?
diarrhea
Which population within NYC is at greatest risk of a crypto infection?
immunocompromised patietns
Why is cryptosporidium such a problem in our drinking water?
tolerant to chlorine, and has animal reservoirs
What are some known health effects associated with arsenic exposure?
skin lesions, cancers, cardiovascular problems,and otehrs
How is arsenic eliminated from our bodies?
methylation
What helps to methylate arensic?
folate supplements
What are the strategies for arsenic mitigation?
well switching, and dig deeper wells
What was the finding of the global enteric multi center study?
the school based education intervention lead to a significant reduction urinary arsenic
What are some examples of bioaerosals?
viruses, bacteria, endotoxins, fungal spots, protozoa, algae, pollen, animal effluents
A heterogeneous conditions characterize by variable airflow obstruction that is partially or completely reversible with appropriate treatment
ASthma
drug for asthma
Albuterol
symptoms of asthma
wheezing, breathlessness, chest tightness, and coughing
What does asthma result from
airway inflammation leading to allergic hyper responsiveness
What are some known risk factors of asthma?
allergies, smoking, obesity, exercise
What are some environmental factors that have been used to explain the epidemic?
dust mites and cockroaches, combustion by-products,, traffic, diesel exhaust, reduced viral exposure, reduced infectious diseases, lack of farm exposure, micronutrients, obesity, acetaminophen, phthalates,
the hypothesis that increased cleanliness has lead to an increase in number of allergic individuals
hygiene hypothesis
How are IgE antibodies involved in allergic reactions?
The creation of IgE antibodies results in an allergic reaction
What are the two stages of an asthma attack?
rapid bronchoconstriction and inflammation
How are allergies and asthma related?
an allergen often triggers an asthma attack
What is the atopic march?
the progression of allergic disease in the early stages of life
a substance (usually a protein) capable of inducing allergy or a specific hypersensitivity
an allergen
What are some common allergens associated with asthma
dust mites, cockroach, cats, mice
What is the revenant agent?
the actual protein on the source that causes the allergic reaction
How does water become contaminated?
Waste seeps into the water, infectious agents are endemic, or get there through human excrement.
What is the evidence that water sanitation leads to improved health
switching to ground instead of river, or filtering, and sanitation lead to the greatest reduction in infectious diseases, not antibiotics
What are the federal regulations around E-waste?
none- shio it off to developing countries, where it is burned in open air, riverside acid baths, and dummping
What are some new EPA regulations for municipal solid waste landfills?
bottom liner and leachate collection, must be treated - can’t be near airports, wetlands, or near earthquake faults
To promote better management of solid waste, provided financial assistance for states to develop solid waste management plans
Solid Waste Disposal Act of 1965
Changed the emphasis from solid waste disposal to recycling and energy recovery - required the US PHS and EPA to police waste disposal
Resource Recovery Act os 1970
significant changes in requirements for the control of hazardous waste storage, treatment, and disposal
resource Conservation Recovery Act on 1976
Directed EPA to regulate disposal of all hazardous waste, treat contaminated surface water running off of landfills, and regulated wastewater sew sludge at landfills
Hazardous and Solid Waste Amendments of 1984
What makes up garbage?
organic materials are the largest component that could be composted - plastics, metals, rubber, and textiles that could be reused or recycled
Where is a lot of the hazardous waste stored?
shipped off to developing countries - always contains various hazard substances, child workers are often engaged in e-recycling, and there are many exposures known to be harmful to health - contaminates food, water, homes, and leads to perinatal exposures among others
What are some strategies to better manage waste?
risk avoidance, risk containment, risk destruction
What is one problem associated with the Resource Conservation and Recovery Act?
excludes many hazardous wastes due to lobbying by industry leaders and oil companies - many hazardous materials aren’t being treated as such.
What are some problems with recycled materials?
purity is not uniform, prices can greatly fluctuate, and lack of market development
What are 3 simple ways to treat water for consumption?
chlorine, sunlight, filtration
What factors influence water quantity?
number of people at a filling point, access to water containers, ability to store water, distance to water source, safety
What is the best to worst ranking of defecation solutions?
toilets, latrines, defecation fields
What are some ways to prevent fecal contamination in food or water sources?
The more latrines, the better, and family based latrines are better than community based - since no one maintains it
What are the steps of a complete water treatment cycle?
Coagulation, sedimentation, filtration, disinfection, storage
What are 4 was fecal matter can be transmitted to food?
unclean hands, flies, social, or water sources
What are three barriers to the Fecal oral transmission?
use toilets, drink safe water, hygiene and handwashing
essential for calcium uptake - low levels can lead to osteoporosis and rickets
vitamin D
Which UV light is blocked by the ozone?
UVB is blocked, expect for the longer wavelength portion, and UVC is blocked completely
What is the relationship between sun exposure and vitamin D/
as sun exposure increases, vitamin d increases
How does the ozone benefit our health/
ozone absorbs UV light, protecting us from harmful rays
UVA
has longer wavelengths, transmitted by normal glass
UVB
medium wavelengths
UV-C
short wavelengths, absorbed by the sun
how did we “fix” the ozone hole?
eliminated freon and other chloroflurocardon from refridgerators
why are CFCs so bad?
they are catalysts that create chlorine ions - this splits up the ozone
the shorter the wavelengths of light the ___ energy
more
what happens with DNA absorbs energetic UV light
causes the DNA to mutate
what happens when there are mutations in somatic cells?
cancer
What are risk factor for skin cancer?
age genetics, environment, and personal habits
Which UV causes most skin cancer?
UVB, since UVC is blocked
What are the two skin cancers grouped under non-melanoma?
basal cell and squamous cell
which is the most deadly form, accounting for 79% of all skin cancer deaths?
melanoma
protects us from the sun by absorbing rays - people with darker skin produce more
melanin
How does melanin protect us?
uv lights attach the pyrimidines rings structure, but uv is absorbed by melanin instead since it has a similar structure
how do sunscreens work?
filters that allow some UV through at varying rates, but not all, in order to significantly decrease amount
international, legally binding commitments that required industrialized countries to reduce/eliminatn ozone harming chemicals
The Vienna Convention and the Montreal Protocol
what are the four main factors of a cancerous cell?
malignancy and uncontrolled growth, clonal, and needs to accumulate mutations
a disease of the somatic cells, due to mutation in growth control genes - requires multiple mutations
cancer
the ability to spread to tissues or organs beyond where it originated from
metastasis
normal functioning growth regulating genes
proto-oncogenes
mutations that slow or block cell growth
tumor suppressor genes
src
an example of an oncogene
where did our molecular understanding from dance come from?
a retrovirus that captured protooncogenes that mutated into oncogenes
Whats lead to the decrease in stomach cancer?
h pylori and reduction of salted or cured food
What are some diseases associated with asbestos?
lung cancer, mesothelioma
why has colorectal cancer increased?
red meat consumption, obesity and physical activity
why has there been an increase in hepatocellular carcinoma??
HBV infection
What makes aflatoxin carcinogenic?
a potent carcinogen pushed by a molt that created a specific codon mutation
Why was breast cancer originally nun’s disease?
association with estrogen, women who have higher exposures are more at risk of breast cancer
