Environmental and Nutritional Disorders: Part I Flashcards
What does the global disease burden estimate?
the burden imposed by environmental disease
what is disability adjusted life year (DALY)?
sum of years of life lost due to immature mortality and disability in a population
What was the GDB in 1990-2010 for HIV/AIDS?
there was a worldwide dramatic increase of mortality due to HIV/AIDS and associated infections
what was the single leading global cause of health loss (morbidity and premature death)?
undernutrition
what was the leading cause of death in developed countries?
ischemic heart disease and cerebral vascular disease
what was the leading cause of death in developing countries?
infectious disease
In the postnatal period, ~50% of all deaths in kids less than 5 years attributed to 3 conditions which are all preventable. What are these conditions?
PNA, diarrheal disease, and malaria
What is the trend associated with neonatal conditions in the GBD for 1990-2010?
its still wide, but its going down
what is the trend associated with diarrhea, lower respiratory infections, and other common infectious diseases in the GBD for 1990-2010?
still wide, but going down
what is the trend associated with HIV/AIDS and tuberculosis in the GBD for 1990-2010?
it had an increase around 2006/2007
Without immediate action, what stands to become the preeminent global cause of environmental disease in the 21st century and beyond?
climate change
climate change will have a serious negative impact on human health by increasing the incidence of a number of diseases; what is the effect of climate change on cardiovascular, cerebrovascular, and respiratory diseases?
these are all worsened by heatwaves and air pollution
climate change will have a serious negative impact on human health by increasing the incidence of a number of diseases; what is the effect of climate change on gastroenteritis, cholera, and other foodborne and waterborne infectious diseases?
contamination of foods and disruption of clean water supplies
climate change will have a serious negative impact on human health by increasing the incidence of a number of diseases; what is the effect of climate change on vector-borne infectious diseases?
there will be an increase in malaria and dengue fever due to increased temps, crop failures, and more extreme weather variations
climate change will have a serious negative impact on human health by increasing the incidence of a number of diseases; what is the effect of climate change on malnutrition?
climate change will increase the incidence of malnutrition by disrupting the crop production
what is toxicology?
the study of the distribution, effects, and mechanisms of action of toxic agents (physical agents, radiation and heat)
What limits the value of establishing “safe levels” for entire populations?
complex interactions between various pollutants and age, genetic predisposition, and different tissue sensitivities of exposed persons create wide variations
the definition of a poison is strictly dependent on what?
dosage
what are xenobiotics?
exogenous chemicals in the environment that may be absorbed into the body
most solvents and drugs are said to be what? and what does this allow them to do?
lipophilic; allows their transport and penetration through the basement membrane
What happens to most solvents, drugs, and xenobiotics in the body?
they are either metabolized to an inactive water-soluble product (detoxification) or activated to form toxic metabolites
What enzyme system is responsible for either detoxifying xenobiotics or convert them into active compounds that cause cellular injury?
Cytochrome P-450
where is the cytochrome P450 enzyme system primarily located?
endoplasmic reticulum of the liver; also present in the skin, lungs, GI mucosa, and other organs
What is produced when P450 metabolizes xenobiotics?
ROS
what are three examples of xenobiotics that P450 metabolizes?
carbon tetrachloride cigarette smoke, and EtOH
What effect does fasting and starvation have on P450?
decreases its activity
Air pollution is especially hazardous to whom?
people with preexisting pulmonary or cardiac disease
The US EPA sets limits on what environmental pollutions? (6)
sulfur dioxide, ozone, carbon monoxide, nitrogen dioxide, lead, and particulate matter
What populations are at risk of ozone exposure?
healthy adults and children; athletes, outdoor workers, and asthmatics
what happens if healthy adults and children are exposed to ozone?
decreased lung function, increased airway reactivity, lung inflammation
what happens if athletes or outdoor workers are exposed to ozone?
they will have a decreased exercise capacity
what happens if asthmatics are exposed to ozone?
increased hospitalizations
What populations are at risk when exposed to sulfur dioxide?
healthy adults, individuals with chronic lung disease, and asthmatics
what happens if a healthy adult is exposed to sulfur dioxide?
they will have increased respiratory symptoms
what happens if individuals with chronic lung disease are exposed to sulfur dioxide?
increased mortality
what happens if asthmatics are exposed to sulfur dioxide?
increased hospitalizations and decreased lung function
What is ozone?
UV radiation + Oxygen
ground level ozone toxicity is largely mediated by what? and these injure what?
free radicals; injure respiratory tract epithelial cells and type I alveolar cells, which cause mild symptoms
What is sulfur dioxide produced by?
power plants burning fossil fuels, copper smelting, and as a byproduct of paper mills
what are the effects of sulfuric acid and sulfuric trioxide?
a burning sensation in the nose and throat, difficulty breathing, and asthma attacks in those susceptible
What particulate matter (soot) particles are the most harmful?
fine or ultrafine particles less than 10 micrometers in diameter
What happens to the particulate matter (soot) that is larger than 10 micrometers in diameter?
they are typically removed in the nose, trapped by the mucociliary epithelium of the airways
Who is at risk for chronic poisoning of carbon monoxide?
those who work in tunnels, underground garages, and highway toll booths with high exposures to automobile fumes
who is at risk for acute toxicity of CO?
improper use of gasoline-powered generators (e.g. during power outages)
How does CO kill?
by inducing CNS depression; widespread ischemic changes
Where is CO concentrated in the brain following toxicity?
basal ganglia and lenticular nuclei
What would you see if someone has survived 24-48 hours after they have been exposed to the CO?
the brain may be slightly edematous, they may have hemorrhages in the pallidum, and there may be hypoxia-induced neuronal changes
What are the likely symptoms a patient will have if they recover from CO poisoning?
impaired memory, vision, hearing, and speech
What is a gross indicator that a patient has been poisoned by CO?
there is a generalized cherry-red color of the skin and mucous membranes
What is the most common indoor pollutant?
tobacco smoke
What makes wood smoke carcinogenic?
polycyclic hydrocarbons
What is associated with bioaerosols as indoor air pollution?
legionnaires disease, viral PNA, pet dander, fungi, molds
what is radon?
a radioactive gas derived from uranium
what is the effect of radon exposure?
it increases the risk for lung cancer (2nd leading cause of lung cancer)
Where might you be exposed to formaldehyde?
building materials, poorly ventilated trailers following disasters
What is sick building syndrome?
when an indoor space to poorly ventilated and indoor pollutants build up
What does lead in the body interfere with?
calcium metabolism
how are children exposed to lead?
flaking lead paint and soil
what are the occupational exposures of lead?
battery manufacturing, pigments, car radiators, and tin cans
Where is most of the lead that is absorbed into the body incorporated? and what is the half life of lead?
bone and developing teeth; half life is 20-30 years
What effect do low levels of lead in the body have?
intellectual issues, behavioral problems, hyperactivity, poor organizational skills in kids
What effect does lead poisoning have on kids?
brain damage
what effect does lead poisoning have on adults?
peripheral neuropathy (wrist drop/ foot drop)
What are lead lines?
radiodense deposits in the metaphyses (which interferes with remodeling of cartilage); also lead lines in the gums
What does lead do to you hematologically?
gives you hypochromic microcytic anemia, basophilic stippling, and ring sideroblasts
What is lead colic?
extremely severe, poorly localized abdominal pain
how can you diagnose microcytic hypochromic anemia with a lab test?
if MVC is less than 80 fL
What is the effect of exposure to mercury?
damages the CNS in the developing brain and also the kidney
what are the main sources of mercury?
contaminated fish (methyl mercury), mercury vapors from metallic mercury in dental amalgams
what are the effects of minamata disease?
cerebral palsy, deafness, blindness, mental retardation, and major CNS defects in children exposed in utero
What are the effects of arsenic exposure?
it interferes with cellular metabolism–> toxicities most prominent in the GI tract, nervous system, skin, and heart
Where might you be exposed to arsenic?
in the soil and water naturally; wood preservatives, herbicides, and herbal medicines
what might you notice after 2-8 weeks post exposure to arsenic?
sensorimotor neuropathy, paresthesias, numbness, and pain
What is a very unique characteristic of arsenic poisoning?
there are chronic skin changes- hyperpigmentation and hyperkeratosis on the palms and soles too; mees lines in the nails
what cancers are you at risk for if exposed to arsenic?
lungs, bladder, and skin (multiple on palms and soles)
What is cadmium poisoning preferentially toxic to?
kidneys and lungs (involve increased ROS
What are the main sources of cadmium?
nickel-cadmium batteries, soil, plants (aka food)
what are the effects of cadmium poisoning?
obstructive lung disease, renal tubular damage, skeletal abnormalities associated with calcium loss
What is Itai-Itai?
a disease in Japan; osteoporosis and osteomalacia with renal disease- came from cadmium pollution in the Jinzu river in the 1950s
What cancer are you more at risk for if you are exposed to cadmium? and where might this happen?
increased risk of lung cancer (if you liver near zinc smelters)
What cancer could benzene cause?
leukemia
What cancer could vinyl chloride cause?
liver angiosarcoma
What toxicants could cause fibrosis?
silica, asbestos, and cobalt
What toxicants could cause lung cancer?
radon, asbestos, and silica
What are two examples of organic solvents that cause occupational health risks?
chloroform and carbon tetrachloride
what does acute exposure to chloroform and carbon tetrachloride cause?
dizziness and confusion leading to CNS depression and coma
what are lower levels of exposure to chloroform and carbon tetrachloride toxic for?
the liver and the kidneys
What are rubber workers exposed to?
benzene and 1,3-butadiene
Benzene is oxidized by hepatic CYP to toxic metabolites that disrupt what?
the differentiation of hematopoietic cells in the bone marrow–> leads to marrow aplasia and increased risk of AML
what is the main source of polycyclic hydrocarbons, and what does exposure to these lead to?
combustion of fossil fuels; scrotal cancers
what are chimney sweeps at risk for?
prostate cancer due to being exposed to polycyclic hydrocarbons
polycyclic hydrocarbons are among the most potent carcinogens and industrial exposure implicated in what cancers?
lung and bladder
What are organochlorines?
synthetic lipophilic products that resist degradation
what are common organochlorines?
pesticides (such as DDT) or non pesticides such as PCBs and dioxin
what effect do organochlorines have on the body?
they disrupt hormonal balance because of antiestrogenic and antiandrogenic activity
What do dioxins and PCBs cause?
folliculitis and a dermatosis known as chloracne
what is chloracne?
an acne with cyst formation, hyperpigmentation, and hyperkeratosis of the face and behind the ears
What do mineral dusts such as coal dust, silica, asbestos, and beryllium cause?
pneumonconioses
What does asbestosis cause?
mesothelioma and black lung
what are ferruginous bodies?
asbestos fibers coated in iron
what is BPA known as?
a potential endocrine disruptor
