Metal Toxicology Flashcards
main heavy metals
lead, mercury and cadmium
natural source of metal contamination
volcanos
environmental distribution of metals: atmospheric contamination
what we look at in ice cores
main way
environmental distribution of metals: water
if it’s in the water it’s coming from the atmosphere mainly
environmental distribution of metals: food
plants can take up toxic metals, mainly cadmium
mercury is the only metal that is
liquid at room temp, good conductor of electricity
mercury is highly toxic in what form?
VAPOR
organic Hg compounds that are produced by anaerobes are
highly lipid soluble and VERY toxic
sources of Hg
switches, light bulbs emissions from industrial plants burning coal & fuel incineration of municipal wastes leaching from Hg containing compounds dental fillings
effects of Hg on human health - burns, rashes, skin irritation
Hg salts
effects of Hg on human health - renal damage
elemental Hg
effects of Hg on human health - vision problems
elemental and organic Hg
effects of Hg on human health - minamata disease
organic Hg
cadmium is similar to the other metal,
zinc
main environmental source of cadmium is from
coal burning but also incineration of wastes
cadmium is most toxic in what form?
ionic
sources of cadmium
charm bracelets plants accumulate - potatoes and grains seefood and organ meets used in nicad batteries pigment in yellow paints TV screens cigarette smoke fertilizers and pesticides
cadmiums effects on human health
our body accumulates in our LIVER & KIDNEYS
severe pain in joints because it replaces calcium
Lead is easy to use as a
pure metal
sources of lead
construction for roofing pipes ammunition used in batteries sinkers in fishing paints glazes PVC mini blinds home remedies
health effects from lead - frank lead poisoning
produces general symptoms like fatigue, myalgia, abdominal pain and headache
health effects from lead - death can result from
encephalopathy, cerebral edema, seizure or renal failure
health effects from lead - cognitive deficits
quantifiable as of a decrease in IQ of 4 points for every increase of 10 ug/dl BI Pb
who is most at risk for lead poisonings???
developing fetuses and children
what therapy is recommended for individuals with high exposure to lead?
chelation therapy
calcium supplements have been shown to
decrease blood lead in pregnant women
what do you do about lead poisoning??
nothing really, you try to eliminate the source of contamination
chemistry of metals - most are electron
acceptors
nonisomorphous replacement
toxic metal replaces the usual metal in a protein, nucleic acid or membrane
metal ion size is the major determinant of
selectivity
calcium is readily replaced by
cadmium
magnesium is readily replaced by
nickel
metal scavenger proteins
have a high affinity for toxic metals, act as a sink for toxic metals
metalothionine is the primary example of
metal scavenger proteins
