HEAVY METALS
      HEAVY METALS
  The term heavy metal refers to any 
  The term heavy metal refers to any 
   metallic chemical element that has a 
   metallic chemical element that has a 
   relatively high density and is toxic or 
   relatively high density and is toxic or 
   poisonous at low concentrations.
   poisonous at low concentrations.
              HEAVY METALS
              HEAVY METALS
     are natural components of the Earth's crust
      are natural components of the Earth's crust
     they cannot be degraded or destroyed
      they cannot be degraded or destroyed
     to a small extent they enter our bodies via food, 
      to a small extent they enter our bodies via food, 
      drinking water and air
      drinking water and air
     as trace elements, some heavy metals (e.g. copper,
      as trace elements, some heavy metals (e.g. copper,
     selenium, zinc) are essential to maintain the 
      selenium, zinc) are essential to maintain the 
      metabolism of the human body
      metabolism of the human body
     however, at higher concentrations they can lead to 
      however, at higher concentrations they can lead to 
      poisoning
      poisoning
     heavy metal poisoning could result, for instance, 
      heavy metal poisoning could result, for instance, 
      from drinking-water contamination (e.g. lead 
      from drinking-water contamination (e.g. lead 
      pipes), high ambient air concentrations near 
      pipes), high ambient air concentrations near 
      emission sources, or intake via the food chain
      emission sources, or intake via the food chain
   THE BIGGEST DISASTERS 
   THE BIGGEST DISASTERS 
       WITH „A SPECIAL 
       WITH „A SPECIAL 
   APPEARANCE” OF HEAVY 
   APPEARANCE” OF HEAVY 
           METALS
           METALS
  1932-1952 Minamata
  1932-1952 Minamata
  Sewage containing mercury is released by 
  Sewage containing mercury is released by 
   Chisso's chemicals works into Minimata Bay in 
   Chisso's chemicals works into Minimata Bay in 
   Japan. The mercury accumulates in sea 
   Japan. The mercury accumulates in sea 
   creatures, leading eventually to mercury 
   creatures, leading eventually to mercury 
   poisoning in the population.
   poisoning in the population.
  In 1952, the first incidents of mercury poisoning 
  In 1952, the first incidents of mercury poisoning 
   appear in the population of MinimataBay in 
   appear in the population of MinimataBay in 
   Japan, caused by consumption of fish polluted 
   Japan, caused by consumption of fish polluted 
   with mercury, bringing nearly 1000 fatalities. 
   with mercury, bringing nearly 1000 fatalities. 
   Since then, Japan has had the strictest 
   Since then, Japan has had the strictest 
   environmental laws in the industrialised world.
   environmental laws in the industrialised world.
   THE BIGGEST DISASTERS 
   THE BIGGEST DISASTERS 
      WITH „A SPECIAL 
       WITH „A SPECIAL 
   APPEARANCE” OF HEAVY 
   APPEARANCE” OF HEAVY 
           METALS
           METALS
  1986-11-01 Sandoz 
  1986-11-01 Sandoz 
  Water used to extinguish a major fire 
  Water used to extinguish a major fire 
   carries c. 30 t fungicide containing 
   carries c. 30 t fungicide containing 
   mercury into the Upper Rhine. Fish 
   mercury into the Upper Rhine. Fish 
   are killed over a stretch of 100 km. 
   are killed over a stretch of 100 km. 
   The shock drives many FEA projects 
   The shock drives many FEA projects 
   forwards. See also "Pollution of the 
   forwards. See also "Pollution of the 
   Rhine at Basel / Sandoz".
   Rhine at Basel / Sandoz".
   THE BIGGEST DISASTERS 
   THE BIGGEST DISASTERS 
      WITH „A SPECIAL 
       WITH „A SPECIAL 
   APPEARANCE” OF HEAVY 
   APPEARANCE” OF HEAVY 
           METALS
           METALS
  1998-04 Spanish nature reserve 
  1998-04 Spanish nature reserve 
   contaminated after environmental 
   contaminated after environmental 
   disaster 
   disaster 
  Toxic chemicals in water from a burst dam 
  Toxic chemicals in water from a burst dam 
   belonging to a mine contaminate the Coto de 
   belonging to a mine contaminate the Coto de 
   Donana nature reserve in southern Spain. C. 
   Donana nature reserve in southern Spain. C. 
   5 million m_ of mud containing sulphur, lead, 
   5 million m_ of mud containing sulphur, lead, 
   copper, zinc and cadmium flow down the Rio 
   copper, zinc and cadmium flow down the Rio 
   Guadimar. Experts estimate that Europe's 
   Guadimar. Experts estimate that Europe's 
   largest bird sanctuary, as well as Spain's 
   largest bird sanctuary, as well as Spain's 
   agriculture and fisheries, will suffer 
   agriculture and fisheries, will suffer 
   permanent damage from the pollution.
   permanent damage from the pollution.