Topic 4 (Environmental & Nutritional Diseases) Flashcards
disorders caused by exposure to chemical or physical agents in the ambient, workplace & personal environments.
Environmental Disease
outdoor, indoor & occupational settings in which humans live & work. (air, food, water, toxic agents)
Ambient environment
environmental factors pertain to the individual (tobacco use, alcohol ingestion, therapeutic & recreational drug use, diet)
Personal environment
Give: HEALTH EFFECTS OF CLIMATE CHANGE
● Cardiovascular, cerebrovascular & respiratory diseases
● Gastroenteritis, cholera, other food & waterborne infectious diseases
● Vector-borne infectious diseases eg. malaria & dengue fever
● Malnutrition
Basic Principles: (Toxicity of ___ & ___)
Toxicity of chemicals & drugs
quantitative concept dependent on dosage
Poison
exogenous chemicals in the
environment that may be absorbed by the body
thru inhalation, ingestion or skin contact.
Xenobiotics
Chemicals may be excreted in
___ or ___ or
eliminated in ___, or may accumulate in ___, ___, ___, or other tissues.
Chemicals may be excreted in urine or feces or
eliminated in expired air, or may accumulate in bone, fat, brain, or other tissues.
may act at the site of entry, or they may be transported to other sites. Some are not modified but most are metabolized (detoxified) to form water soluble products or activated to form toxic metabolites.
Chemicals
Chemicals may act at the site of entry, or they may be transported to other sites. Some are not ____ but most are ____ (detoxified) to form ____ or activated to form ____.
Chemicals may act at the site of entry, or they may be transported to other sites. Some are not modified but most are metabolized (detoxified) to form water soluble products or activated to form toxic metabolites.
Most solvents & drugs are ___ w/c facilitates transport in blood by lipoproteins & penetrate thru lipid component of cell membranes.
lipophilic
Most solvents & drugs are lipophilic w/c facilitates transport in blood by ____ & penetrate thru lipid component of cell membranes.
lipoproteins
Most solvents & drugs are lipophilic w/c facilitates transport in blood by lipoproteins & penetrate thru ____.
lipid component of cell membranes
chemicals undergo hydrolysis, oxidation or reduction.
Phase I reaction
Products here are ___ into ___ cds thru Phase I reactions of ___, ___, ___ & ___.
Products here are metabolized into water-soluble cds thru Phase I reactions of glucuronidation, sulfation, methylation & conjugation w/glutathione (GSH).
Phase I reactions;
most active in ER of liver
Cytochrome P450 system
catalyzes detoxification or converting xenobiotics to active cds that cause cellular injury → ROS (cellular damage).
Cytochrome P450 system
ROS
cellular damage
metabolizes acetaminophen, barbiturates & alcohol.
CP450
enzymes vary in activity ( decreased by fasting or starvation & increased by alcohol ingestion & smoking).
CP450
Outdoor Air Pollutants
- Ozone
- Sulfur dioxide particles & acid aerosols
- Carbon monoxide (CO)
- Systemic Hypoxia
- Acute CO Poisoning
- Chronic CO Poisoning
gas formed by sunlight-driven reactions involving nitrogen oxides; emitted by automobile exhaust; generates free radicals → injures lining epithelium of respiratory & alveoli.
Ozone
are released by coal & oil-fired power plants & industries using these fuels. Particles <10 microm when inhaled → phagocytosed → elease mediators → inflammatory reaction
Sulfur dioxide particles & acid aerosols
non-irritating, colorless, tasteless, odorless gas.
Carbon monoxide (CO)
Sources are: automotive engines, industries using Fossil fuels, home oil burners & cigarette smoke.
Carbon monoxide (CO)
binds to hemoglobin & prevent 02 transport.
Carbon monoxide (CO)
CNS depression
Systemic Hypoxia
cherry-red color skin &
mucous membrane
Acute CO Poisoning
ischemic changes brain
Chronic CO Poisoning
Indoor Air Pollution
- Smoke
- Radon
- Bioaerosols
from burning of organic materials w/diff. Oxides of nitrogen & carbon particulates. (wood, dung, charcoal)
Smoke
radioactive gas from uranium; present in soil & homes; cause lung cancer.
Radon
pathogenic microbiologic agents. (Legionnaire’s disease.; Viral pneumonia; common cold; allergens from pet dander, dust mites, fungi & molds → rhinitis, eye irritation, asthma.
Bioaerosols
is a readily absorbed metal that binds to sulfhydryl groups in proteins and interferes with calcium metabolism, leading to hematologic, skeletal. neurologic, Gl, and renal toxicities.
Lead
Occurs through contaminated air, food, and water.
Lead
Major sources: house paints, gasoline, mines,
batteries & spray paints
Lead
Binds to sulfhydryl groups in some proteins w/c results to CNS, GI & kidney damage.
Mercury
Used in cosmetic, component of diuretics, remedy for syphilis.
Mercury
Main sources - contaminated fish & dental amalgams
Mercury
cerebral palsy, deafness, blindness & CNS defects
Minamata Disease
Ulcerations & bloody diarrhea
GIT
acute tubular necrosis & renal failure
Kidney
Toxicities prominent in GITl, nervous system, skin & heart.
Arsenic
Found naturally in wood preservatives, herbicides & other agri products.
Arsenic
severe abdominal pain, diarrhea, cardiac arrhythmias, shock, respiratory distress syndrome, acute encephalopathy.
Arsenic (Acute toxicity)
hyperpigmentation & hyperkeratosis of skin → basal & squamous cell carcinoma.
Arsenic (Chronic toxicity)
Assisted increase risk with lung carcinoma.
Arsenic
Metals as Environmental Pollutants
- Lead
- Mercury
- Arsenic
Industrial and Agricultural Exposure
- Organic solvents
- Polycyclic hydrocarbons
- Organochlorines
- Non-pesticides organochlorines
- Polychlorinated biphenyls & dioxin (TCDD)
chloroform, carbon tetrachloride, benzene
Organic Solvent
dizziness, confusion -> CNS depression or coma
Acute exposure
emitted upon combustion of coal & gas; present in tar & soot
Polycyclic hydrocarbons
Industrial exposure cause lung & bladder CA.
Potent carcinogens
used as pesticides (DDT)
Organochlorines
eg: PCBs
Non-pesticides organochlorines
Direct irritant effect on tracheobronchial mucosa-> inflammation & increase mucus production; recruitment of leukocytes → increase elastase production → lung injury → emphysema.
Mechanisms of Tobacco-Induced Diseases
Carcinogenesis. Polycyclic hydrocarbons & nitrosamines → lung CA; oral cavity, esophagus, pancreas & bladder CA.
Mechanisms of Tobacco-Induced Diseases
increase platelet aggregation, decrease myocardial 02 supply w/increase 02 demand.
Atherosclerosis (MI) -Mechanisms of Tobacco-Induced Diseases
Spontaneous abortions & preterm births in maternal smoking.
Mechanisms of Tobacco-Induced Diseases
Passive smoke inhalation
Mechanisms of Tobacco-Induced Diseases
isk for lung CA, coronary atherosclerosis & Ml; increase frequency of respiratory illness & asthma. Blood levels of cotinine.
Passive smoke inhalation
Effects of Alcohol
● Drowsiness @200mg/dl; stupor @300ml/dI; coma & respiratory arrest at higher levels.
● Fat accumulation in the liver → Lactic acidosis
● Acute effects: Acetaldehyde toxicity → Flushing,
Tachycardia
● Hyperventilation
● Lipid peroxidation of CM
● Release of endotoxin (LPS) from intestinal flora →
release INF &
Fat accumulation in the liver
Lactic acidosis
Acute effects: (effects of alcohol)
Acetaldehyde toxicity → Flushing,
Tachycardia
Acute Alcoholism
● Fatty change or hepatic steatosis - fat droplets in cytoplasm
● Gastric damage → gastritis & ulceration
● CNS - depressant - disordered motor & intellectual
behaviour; at higher levels may cause respiratory arrest
Chronic Alcoholism
● Liver- alcoholic hepatitis & cirrhosis → increase risk hepatocellular CA
● GIT - massive bleeding
● Neurologic effects - peripheral neuropaties;
Wernicke-Korsakoff syndrome; cerebral atrophy, cerebellar degeneration, optic neuropathy.
● Cardiovascular system: alcoholic cardiomyopathy - myocardium - dilated congestive myopathy; increase incidence HPN
● Pancreatitis
● Effects on Fetus - “Fetal Alcohol Syndrome”,
microcephaly, growth, retardation, facial
abnormalities, reduce mental functions
● Carcinogenesis - cancers of oral cavity,
esophagus, liver, breast (females)
● Malnutrition & Vit. B deficiency
alcoholic hepatitis & cirrhosis → increase risk hepatocellular CA
Liver
massive bleeding
GIT
peripheral neuropaties;
Wernicke-Korsakoff syndrome; cerebral atrophy, cerebellar degeneration, optic neuropathy.
Neurologic effects
Effects on Fetus
“Fetal Alcohol Syndrome”,
microcephaly, growth, retardation, facial
abnormalities, reduce mental functions
cancers of oral cavity,
esophagus, liver, breast (females)
Carcinogenesis
ADVERSE REACTION MINOCYCLINE
A. Diffuse blue-gray pigmentation forearm due to minocycline admn.
B. Drug metabolites deposits (iron, melanin pigment) in the dermis
Combination estrogen with progestin (MHT) (HRT) - Increase risk of breast CA, stroke, venous
thromboembolism (DVT & PE)
Oral contraceptives (OCs)