heavy metals Flashcards
list some examples of heavy metals
1) lead
2) mercury
3) cadmium
4) tin
5) iron
what are some sources of lead pollution
1) lead acid batteries
2) lead flashing used in construction
what are the effects of lead pollution
1) construction workers may inhale lead dust or absorb it through the skin causing acute issues such as brain damage and paralysis and eventually death
2) rainwater flowing over lead rood flashing may inhibit the growth of moss and lichens
how can lead pollution be controlled
1) water pipes= all lead water pipes have been replaced preventing chronic exposure, lead solder has also now been replaces
2) petrol additives= lead replaced with chemicals such as benzene
3) fishing weights = replaced with less toxic metals
what are the sources of mercury pollution
1) disposal of items containing mercury such as batteries and thermometers
2) chemical plants that produce chlorine using mercury electrodes
3) combustion of coal
what are the effects of the chemical form on the toxicity of mercury
1) liquid mercury is not easily absorbed through the skin or gut although vapors may be absorbed in the lungs if inhaled
2) inorganic mercury such as mercury oxide is absorbed well in the gut
3) organic mercury is absorbed easily through the skin and the gut and inhalation.
causes issues such as
- kidney damage
- brain damage
how can mercury pollution be controlled
1) replace mercury thermometers with alcohol or electronic thermometers
2) removed from effluents by reverse osmosis or activated carbon filters
3) ion-exchange filters
4 )dispose at high PH to reduce the solubility
what are the sources of cadmium pollution
1) disposal of old nickel-cadmium batteries
2) incineration of wastes containing cadmium pigments such as paints
3) drainage water of cadmium and zinc mines
what are the effects of cadmium
brain damage paralysis lung cancer kidney failure skeletal collapse
how can cadmium pollution be controlled
1) restrict of ban cadmium uses
2) disposed of in hazardous landfill
