Environmental Health Flashcards
What are the five main points about chemistry?
- Everything is a chemical
- Dose makes the poison (low dose = safe)
- There is no difference between natural and synthetic form of a chemical
- “Natural” is not automatically good, artificial is not automatically bad.
- A chemical’s toxicity is based on what is bound to (things that would normally be dangerous may be safe it bound to something stable)
What is the #1 killer of anything in the US?
Chronic disease - 70% of all deaths
How percentage of people have chronic diseases?
50% have 1 +
25% have 2+
Why do we have more chronic disease deaths compared to other deaths?
Increased life span, improved detection and diagnosis
Higher rates of chronic disease in younger pts
What is the #1 and #2 cause of death in the US?
Cardiovascular disease
Cancer
What is the #1 cause of disability?
Arthritis
What is the #1 cause of preventable death?
Tobacco use
What preventative screenings do people not take advantage of?
Mammograms
Colonscopies
can help decrease Chronic disease burden if you get it checked!!!
What are the things that ACTUALLY kills people?
Tobacco use #1
Pollutant and toxins is 2.3% though!
This is above motor vehicle crashes, firearms, risky sexual behavior, illicit drug use
What are the 4 ways that we come into contact with toxic substances?
The food chain
Polluted water
Airborne exposure
Dermal exposure
increase in human population leads to more pollutants :(
What is bioaccumation vs bioremediation?
Bioaccumulation is us making toxic byproducts, and this is greater than the rate at which it is bioremediated - leading to pollution with time
Exposures to environmental pollutants leads to what percent of global disease burden?
24%
What do pollutants induce that leads to problems?
signaling pathways that lead to oxidative-stress
What can carcinogens do?
Alter DNA and its expression
Stimulate rapid growth
May also impact inflammation/immune processes
Confound cell repair mechanisms in hormone-sensitive tissues
Increased inflammation
Impaired immune surveillance
What are some common carcinogens?
radon, asbestos, benzene, coal, soot and smoke, arsenic, triclosan
What is triclosan?
Antimicrobial back in the day that was put in everything but is actually a carcinogen
try closan up your wound? more like try cancer!
What is cancer alley?
85-mile stretch along Mississippi River
Over 150 refineries and factories
Lots of synthetic chemicals, leading to a LOT more cancer cases
What chemicals can cause problems regarding Obesity/Metabolic Syndrome/Diabetes
Chemicals → herbicide, triclosan, flame retardants, stain repellents, nonstick compounds, DDT
interfere with thyroid function
can mimic naturally occurring hormones
xenobiotics stored in fat released in blood with wt loss
may undermine further efforts to lose weight
Others → arsenic, cadmium
increase pancreatic oxidative stress
may contribute to DM
How do toxins lead to vascular disease?
Toxic metals → oxidative stress
Strong connection w/development & progression of vascular diseases
How do toxins lead to endocrine disruption
Pesticides, toxic metals, and many other common chemicals can interfere with **hormonal signals **to various organ systems
What is environmental toxicology?
Deals with potentially harmful impact of chemicals in our environment
What is acceptable daily intake?
daily intake of a chemical that appears to be associated with minimal to no risk over lifetime
In the US - FDA and Dept of Agriculture regulate
Different standards in different countries
What is a hazard of an agent?
ability of an agent to cause injury
What is risk
frequency of undesirable occurrence after exposure
What two routes of exposure do yoyu get with industrial and atmospheric?
inhalation, transdermal
What is the route of exposure for water/soil
inhalation, ingestion, dermal contact
What is the duration of exposure for acute vs chronic?
acute - single or multiple over a brief period (seconds to 1-2 days)
chronic - multiple exposures over a longer period of time
Difference between bioaccumulation vs biomagnification?
Bioaccumulation - intake of contaminant > ability to excrete or metabolize
Biomagnification - increased concentration of a given contaminant as it goes up food chain
Explain the bioaccumulation of DDT
Small herbicides start in smaller things, and then magnifies
What are the secondary effects of DDT
blaque plague d/t more mice
What is persitence of a toxin?
resist environmental, often animal metabolic breakdown
What is toxicity?
rating based on repeated exposures which result in human or environmental adverse outcomes
What is CO
carbon monoxide
Colorless, tasteless, odorless, nonirritating
What are the s/s of CO poisoning
Hypoxia - affects brain/heart the most
Headaches, nausea, dizziness, LOC
Variability in individual responses
Chronic exposure to low levels may lead to undesirable effects
What is the treatment for CO poisoning?
removal from source, maintaining respiration, administer O2 within limits of O2 toxicity
give O2 get rid of CO basically
What is SO2 and what does it form when it comes into contact with mucous membranes?
colorless IRRITANT gas from fossil fuels
Colorless, irritant gas - fossil fuels
Forms sulfuric acid on contact with mucous membranes
Irritant to eyes, mucous membranes, skin and respiratory tract
Eye and nasal drainage, bronchospasm
What is chronic SO2 lead to?
Adaptation, but leads to development of heart and lung disease
Treatment of SO2 exposure
symptomatic
What does most of SO2 come from?
Electricity makes up 69%
What is NO2
Brownish, irritant gas
Fires, fresh silage
deep lung irritant
think brown = dead trees, dead lungs
What are the s/s of NO2 and biggest concern
eye and nose irritation, cough, mucoid/frothy sputum, dyspnea, chest pain
biggest concern: Can cause pulmonary edema, subacute inflammation, or chronic lung lesions
Treatment of NO2
Symptomatic
Manage lung irritation, pulmonary edema
What is ozone
Bluish irritant gas occurring normallyin atmosphere → absorbs UV light
High concentrations - high-voltage electrical equipment, air/water purifiers, polluted urban air
think water has oxygem, water is blue, blue electrical current
what does ozone lead to?
irritates mucous membranes
mild - upper respiratory inflammation
severe - deep lung irritation, pulmonary edema
long term → morphologic/functional respiratory tract changes
What is the treatment of ozone
symptomatic
management of deep lung irritation, pulmonary edema
What is a halogenated aliphatic hydrocarbon?
chloroform - can make people pass out
What is a patient population that is often exposed to halogenated aliphatic hydrocarbon?
dry cleaners
What are the common symptoms of acute halogenated aliphatic hydrocarbon exposure? Chronic?
CNS depression (MC)
can effect EVERY organ system
impaired memory, peripheral neuropathy
What are the three aromatic hydrocarbons?
Benzene
Toluene
Xylene
Where are benzenes found?
Combustion
liquids (dyes, detergents, pesticides, cleaning products, paint strippers, adhesives_
solids (plastics, resins, synthetic fibers, rubber lubricants, pharmaceutical solvent)
What are the chronic symptoms seen in benzene that are not seen in other aromatic hydrocarbons (toluene and xylene)?
Myelotoxicity
bone marrow suppression
Which aromatic hydrocarbon is fetotoxic?
toluene
toluene = toddler
What are the symptoms of toluene and xyelene
CNS depressant, skin irritant
What is DDT and the symptoms?
Organochlorine
Pesticide - causes CNS STIMulation (unlike the others that is depression)
tremor, convulsions
chronic → enhanced tumor formation (endocrine disruption)
Double D battery
What are the organophosphorics?
Not persistent
Have cholinergic properties (opposite of anticholinergics - leads to tremors, dyspnea, lacrimation, confusion, fasciculations
Some compounds have neuropathy target esterase → progressive demyelination of longest nerves)
Treatment of organophosphorics
Acute - symptomatic - O2, airway maintenance
No treatment for delayed neurotoxicity
What are bipyridyls?
Reduce to free radicals - has been fatal in humans
Accumulates slowly in lung → edema, alveolitis, fibrosis
What are the symptoms of bipyridyls?
initially manifest as hematemesis, bloody stools
Few days → respiratory distress, hemorrhagic pulmonary edema
Hepatic, renal, myocardial involvement possible
Death may take several weeks
Think of pyr = pyro = blood. Bi = 2 = effects lungs
What is the treatment of bipyridyls?
absorption prevention (gastric lavage, cathartics, adsorbents)
after absorption, tx successful <50% of time
O2 cautiously for dyspnea - may aggravate pulmonary lesions
What is agent orange and what does lead to?
Kills plants instantly
Large doses - coma, generalized muscle weakness and hypotonia
Kidney or liver dysfunction
Linked to Non-Hodgkin’s Lymphoma
What is glycophasate?
most widely used herbicide in world
May damage important crops even when used as directed
Skin and eye irritant
Can be fatal in large doses (less so than other herbicides)
No tx for glyphosate toxicity
What people are exposed to lead the most?
Workers in lead smelters and storage battery factories
also other mechanical
What does lead bind to and what does it lead to?
99% binds to Hb
initially in soft tissues (kidney and liver)
eventually redistributed to bone, teeth, hair
does cross placenta
What are the symptoms of lead?
Neurotoxic (cognitive delays, lead palsy)
CV and renal
Anemic
Other systems
Metallic taste, anorexia, muscle discomfort, malaise, headache, constipation or diarrhea, “lead colic “
What is the treatment of lead poisoning?
removal of source, symptomatic, chelation in acutely high levels
What is the exposure of mercury most common?
Fish
chloralkali industry (bleach), alkaline batteries, fluorescent bulbs, thermometers, scientific equipment, dentists, gold mining, pigments
Thimerosal - antimicrobial - preservative in vaccines
What does mercury affect first? Chronic?
lungs first
then
acute or chronic - insomnia, memory loss, fatigue, cognitive difficulties
Neuromuscular - muscular atrophy, weakness, paresthesia, tremors, movement disorders, paralysis
Sensory - deficit in vision/hearing, slurred speech, movement disorders, paralysis
Death may occur with enough exposure
Other symptoms - ↑ HR, labile pulse, salivation, N/V/D, abdominal pain, gingivitis, renal damage
Fetal - mental retardation, neuromuscular deficits
Even if no maternal symptoms
symptomatic care
Lungs Mercury Neuromuscular Sensory
LMNS
What is arsenic MC exposure?
Drinking water
also exposure in herbicides/insectides
humans are more susceptible than other animals to arsenic toxicity
What are the symptoms of arsesnic?
inhibits ATP, can cause cell apoptosis
What are the Polychlorinated Biphenyls
Industrial fluids and lubricants, plasticizers, wax extenders, flame retardants
What are the symptoms of PCBs?
dermatologic problems, hepatotoxicity, elevated plasma triglycerides
Psych - Adverse behavioral effects, intellectual deficits
Carcinogenic (melanoma, breast, pancreatic, thyroid)
Possible immunotoxicity and teratogenicity
Wasting syndrome, thymic atrophy
What are brominated flame retardants?
Added to plastics, foam, and fabrics
Escape into general environment where they resist degradation
Widespread exposure in virtually all pts
Concentrations of several BFRs in blood and breast milk in US
Nearly 10x higher than in Europe
Polybrominated diphenyl ethers (PBDEs) - type of BFR that can interfere with normal brain development/function and cause other adverse health effects
What are perfluorinated compounds?
PCF
leads to thyorid disease and cholestrol
What are endocrine disruptors?
Any chemical with effects on endocrine system
ubiquitous
effects hormones (typically thyroid, estrogen, or testosterone)
