What are the symptoms of exposure to mercury and arsenic?

Exposure to mercury can cause symptoms which include
insomnia, nervousness, tremors, muscle twitches, mood swings and deficits on cognitive
tests. At higher amounts, it may affect the respiratory system and the kidneys and could
result in death. In fetuses, infants and children, it can cause neurological problems.
Exposure in the womb can affect the developing nervous system and brain. Therefore,
children are most vulnerable. Arsenic exposure has been associated with certain types of
skin cancer. Studies  show a possible link with lung, bladder, liver, colon, and kidney
cancers. Tremors, headaches and numbness as well as stomach upsets, diabetes and blood
pressure can all be affected. If children are exposed, they have a risk later in life of
developing respiratory diseases, lung cancer and it may adversely affect their
I.Q.'s.