Trace and Toxic Elements (F) Flashcards
When are trace elements considered essential?
If a deficiency impairs a biochemical or fxnal process and replacement of element corrects impairment
Essential trace elements are associated w/ what?
W/ an enzyme or other protein as an essential component or cofactor
Excess concs. of essential trace elements are associated w/ what?
W/ some degree of toxicity
What are the exs of trace elements (in mg/L)?
1) Iron
2) Copper
3) Zinc
What are the exs of ultratrace elements (w/c are
1) Selenium
2) Chromium
3) Manganese
What is the characteristic of non-essential trace elements?
These are of medical interest
Why are non-essential trace elements of medical interest?
Because many of them are toxic
Sxs must be collected w/ what (in connection w/ sx collection and processing)?
W/ scrupulous attention to details (such as anticoagulant, collection apparatus, and sx type)
What is the characteristic of trace elements in biologic sxs?
These are of low conc.
What is the characteristic of trace elements in environment?
These are ubiquitous
Since trace elements are of low conc. (in biologic sxs) and ubiquitous (in environment), what must be done (in connection w/ sx collection and processing)?
Much care must be taken (to avoid contaminating sxs)
What must be used (in terms of sx collection and processing)?
1) Special sampling
2) Collection devices
3) Specially cleaned glassware
4) H2O and rgnts of high purity
What must be done to the lab environment (in connection to sx collection and processing)?
It must be carefully controlled
How can the lab environment be carefully controlled (in connection w/ sx collection and processing)?
1) Placement of trace elements (in separate room)
2) Use of sticky mats (at doors)
3) Non-shedding ceiling tiles
4) Controlled air flow
5) Disposable booties
What are the methods for trace elements?
1) Atomic emission spectroscopy (AES)
2) Atomic absorption spectroscopy (AAS)
3) Inductively coupled plasma mass spectrometry (ICP-MS)
What are the 3 most impt components of AE spectrophotometer (in connection w/ AES)?
1) Source
2) Wavelength selecting device
3) Detector
What is the characteristic of the source (w/c is an impt component of AE spectrophotometer)?
It is sufficiently hot (to produce excited-state spp.)
What is the use of wavelength selecting device (as a most impt component of AE spectrophotometer)?
For spectral dispersion of radiation and separation of analytic line from other radiation
What is the action of the detector (as 1 of the most impt components of AE spectrophotometer)?
Permitting measurement of radiation intensity
What should be done to liquid sx containing element (in connection w/ AES)?
It is converted into an aerosol and delivered into source (where it receives energy to emit radiation)
The intensity of emitted radiation is correlated to what (in connection w/ AES)?
It is correlated to conc. of an analyte and is basis for quantitation
What is the flow of the simplified schematic of AES?
Flame or plasma (light emission) -> monochromator -> detector
What is AAS (what is its principle)?
It is an analytic procedure for quantification of elements through absorption of optical radiation by free atoms in gas phase
Spectra of atoms are line spectra, sp. for absorbing elements
What are the 4 most impt components of AA spectrophotometer (in connection to AAS)?
1) Radiation light source
2) Atomizer
3) Monochromator
4) Detector
What is the action of radiation light source (as 1 of the most impt components of AA spectrophotometer)
Emits spectrum of analyte
What is the component of AA spectrophotometer in w/c atoms of element are formed?
Atomizer
What is the action of monochromator (as 1 of the most impt components of AA spectrophotometer)?
For spectral dispersion of radiation and separation of analytic line from other radiation
What is the action of detector (as 1 of the most impt components of AA spectrophotometer)?
Permitting measurement of radiation intensity
What is the flow of the simplified scheme of AAS instrumentation?
Light source -> flame or graphite furnace (light absorption) -> monochromator -> detector
What is ICP-MS?
It is a state-of-the-art analytic technique for elemental analysis
What is the action of ICP-MS?
It measures mass-to-charge ratio (m/z) of selected analyte ions
ICP-MS includes what?
1) Ion source
2) m/z analyzer
3) Ion detector
Argon plasma induced by ICP instruments generates what (in connection w/ ICP-MS)?
High temp (~ 6,000 - ~ 10,000 K)
What are the several purposes that are served by argon plasma induced by ICP instruments (w/c generates high temp; in connection w/ ICP-MS)?
1) Dries droplets (produced by nebulizer)
2) Vaporizes dried particles
3) Atomizes any molecular spp.
4) Thermally ionizes atoms
What are the interferences for / in ICP-MS?
1) Spectroscopic
2) Non-spectroscopic
Spectroscopic interferences results from what (in connection w/ ICP-MS)?
From a spectral overlap w/ spectrum of target analyte
What are the exs of ICP-MS spectral interferences?
1) Polyatomic spp. (whose m/z may overlap m/z of target analyte)
2) Nearby elements (in periodic table)
3) Doubly charged ions
What is the ex of non-spectroscopic interference in ICP-MS?
Matrix interferences
What are non-spectroscopic interferences?
Anything interfering w/ atomization
What is the principle of elemental speciation (in connection w/ ICP-MS)?
Because toxicity of an element may vary by its chemical form, methods are needed to identify specific chemical forms
What is hyphenated analysis (in connection w/ elemental speciation)?
It is the combination of complementary analytic techniques to measure sp. form of analyte
What is under elemental speciation (in connection w/ ICP-MS)?
Liquid chromatography-ICP-MS (LC-ICP-MS)
What are the alternative analytic techniques (in connection w/ ICP-MS)?
1) Neutron activation analysis, voltametric methods
2) Ion chromatography
3) Gas chromatography
4) Mass spectrometry
5) Laser ablation ICP-MS (LA-ICP-MS)
Provide exs of trace elements
1) Aluminum
2) Arsenic
3) Cadmium
4) Chromium
5) Copper
6) Iron
7) Lead
8) Mercury
9) Manganese
10) Molybdenum
11) Selenium
12) Zinc
What are the health effects caused by aluminum?
1) Interference w/ enzymatic processes
2) Encephalopathy
3) Bone disease
4) Proximal myopathy
5) Increased risk of infection
6) Ingestion orally
7) Inhalation
8) Parenterally
How are the health effects caused by aluminum primarily measured?
By ICP-MS or GFAAS
What are the characteristics of the health effects caused by arsenic?
1) These are non-essential
2) These have no known fxn in human physiology
What is the health effect caused by arsenic?
It is toxic
How can exposure to arsenic occur?
1) Ingestion in food (seafood)
2) Ingestion of H2O
3) Ingestion of drink
3) Inhalation
What are the forms of health effects caused by arsenic?
1) Nontoxic (organic forms clear rapidly)
2) Toxic (inorganic forms clear slowly)
In terms of toxicity brought by arsenic, exposure to arsenic can lead to what?
1) Acute intoxication
2) Chronic intoxication
What does inorganic form (in terms of toxicity of arsenic) produce?
Symptoms (w/c can be lethal)
What is the characteristic of organic spp. (in connection w/ toxicity brought by arsenic)?
These are relatively non-toxic
What is the characteristic of health effects caused by cadmium?
1) These are non-essential
2) These have no known fxn in human physiology
What is the health effects brought by cadmium?
These are toxic
How can exposure to cadmium occur?
1) Inhaled in tobacco smoke
2) Ingested in food
How is absorption of cadmium done?
1) Inhaled (10 - 50%)
2) GI (5%)
3) Excretion in feces (90%)
The toxicity brought by cadmium can lead to what conditions?
1) Renal dysfxn
2) Nasal epithelial and lung damage
3) Respiratory distress
4) Nausea
5) Vomiting
6) Abdominal pain (if ingested in great amts)
What are the characteristics of the health effects caused by chromium?
1) These are essential
2) These helps maintain metabolism of glucose, fat, and chole
What are the actions done to chromium (in connection to its absorption, transport, and excretion)?
Absorbed -> bound in blood to transferrin -> transported by albumin
The deficiency of chromium can lead to what conditions?
1) Glucose intolerance
2) Glycosuria
3) Hypercholesterolemia
4) Decreased longevity
5) Decreased sperm cts
6) Impaired fertility
The toxicity caused by chromium can lead to what conditions?
1) Dermatitis
2) Skin ulcers
3) Eczema (cutaneous contact)
4) Airway irritation and obstruction
5) Lung CA (inhaled)
What are the characteristics of the health effects caused by copper?
1) These are essential
2) A cmpt of several metalloenzymes
How does copper exposure occur?
Ingested in food (~ 10 mg/day)
How does absorption of copper occur?
1) Dietary intake (50 - 80%)
2) Excretion of dietary intake in feces (50%)
3) Excretion in urine and sweat (3%)
Copper deficiency can lead to what conditions?
1) Neutropenia
2) Hypochromic anemia
3) Osteoporosis
4) Decreased pigmentation of skin
5) General pallor
Copper toxicity can lead to what condition?
Wilson’s disease (neurologic disorders, liver dysfxn, Kayser-Fleischer rings in cornea)
What are the characteristics of the health effects caused by iron?
1) These are essential
2) A cmpt of hgb and myoglobin
How can exposure to iron occur?
Ingested in food
What must be done to exposure to iron (in connection to absorption)?
It must be reduced to FE(II) for absorption
How can absorption of iron occur?
Dietary intake (10%)
How is transport of iron done?
It is carried by transferrin to bone marrow and incorporated into hgb
Iron deficiency can lead to what condition?
Anemia
Iron toxicity can lead to what conditions?
1) Tissue accumulation
2) Liver fxn
3) Hyperpigmentation
What are the characteristics of health effects caused by lead?
1) These are non-essential
2) No known fxn in human physiology
3) These are toxic
How can exposure to lead occur?
1) Respiratory
2) GI
How can absorption of lead occur?
1) Inhaled (30 - 40%)
2) Variable in GI
How can excretion of lead occur?
1) Urine (76%)
2) Feces (16%)
3) Hair (8%)
4) Sweat
5) Nails
Lead toxicity can lead to what conditions (in children)?
1) IQ declines
2) Clumsiness
3) Gait issues
4) Headache
5) Behavioral changes
6) Seizures
7) Cognitive and behavioral problems
Lead toxicity can lead to what conditions (in adults)?
1) Peripheral neuropathies
2) Motor weakness
3) Chronic renal insufficiency
4) Systolic hypertension
5) Anemia
What are the characteristics of health effects caused by mercury?
1) These are non-essential
2) No known fxn in human physiology
3) These are toxic
How can exposure to mercury occur?
1) Inhalation
2) Ingestion (fish)
3) Cutaneous
4) Injection (tattoo pigments)
5) Dental amalgams
How can mercury absorption occur?
1) Inhaled (80%)
2) GI (~ 0%)
What are the ways for excretion of mercury?
1) Fecal
2) Urinary
Mercury toxicity is primarily through what?
Primarily through rxn w/ sulfhydryl grps
What are the ways to acquire mercury toxicity?
1) Inhaled vapor
2) Inorganic salts
Inhaled vapor (in connection w/ mercury toxicity) can lead to what conditions?
1) Nervous
2) Digestive
3) Immune systems
Inorganic salts (in connection w/ mercury toxicity) can lead to what conditions?
1) Skin
2) Eyes
3) GIT
4) Kidneys
What are the characteristics of the health effects caused by manganese?
1) These are essential
2) A cmpt of metalloenzymes
3) An active activator
How can absorption of manganese occur?
Dietary intake (2 - 15%)
What are the cmpts that affects manganese absorption?
1) Iron
2) Ca
3) Phosphates
4) Fiber
Manganese deficiency can lead to what conditions?
1) Blood clotting defects
2) Hypocholesterolemia
3) Dermatitis
4) Heart and bone problems
5) Stunted growth (in children)
Manganese toxicity can lead to what?
1) Nausea
2) Vomiting
3) Headache
4) Disorientation
5) Memory loss
6) Anxiety
7) Compulsive laughing or crying
What are the characteristics of the health effects caused by molybdenum?
1) These are essential
2) A cmpt of at least 3 enzymes
How can absorption of molybdenum occur?
Dietary intake (25 - 80%)
How can excretion of molybdenum occur?
1) Urine
2) Bile
What is the characteristic of molybdenum deficiency?
It is an inherited disorder
What are the causes of molybdenum deficiency?
1) Seizures
2) Anterior lens dislocation
3) Decreased brain weight
4) Death prior to age 1
What is the characteristic of molybdenum characteristic?
It is rare
Molybdenum toxicity is related to what?
Elevated uric acid in blood and an increased incidence of gout
What are the characteristics of the health effects caused by selenium?
1) These are essential
2) Part of cellular antioxidant defense system against free radicals
3) Involved in metabolism of thyroid hormones
How can selenium exposure occur?
1) Food
2) Drinking H2O
How can absorption of selenium occur?
Dietary intake (50% >)
How can excretion of selenium occur?
1) Urine
2) Feces
3) Sweat
Selenium deficiency can lead to what conditions?
1) Cardiomyopathy
2) Muscle weakness
3) Osteoarthritis
What are the characteristics of selenium toxicity?
1) It is rare
2) Only from 1 form of selenium
3) Not present in food
Selenium toxicity causes what?
1) Nausea
2) Vomiting
3) Hair loss
4) Nail changes
5) Diarrhea
What are the characteristics of the health effects of zinc?
1) These are essential
2) These influences 300 enzymes > and synthesis and metabolism of proteins
3) Participates in glycolysis and chole metabolism
How does zinc absorption occur?
Occurs mainly in small intestine
What are the distribution of zinc in the blood?
Between:
1) RBCs (80%)
2) WBCs (3%
How can zinc excretion occur?
In feces (90%)
What is the characteristic of zinc deficiency?
It is widespread
Zinc deficiency causes what conditions?
1) Growth retardation
2) Slow skeletal maturation
3) Testicular atrophy
4) Reduced taste perception
Zinc toxicity causes what conditions?
1) GIT symptoms
2) Decreased heme synthesis
