1 paroxysmal Pertaining to or marked by paroxysm; caused by paroxysms or convulsions of nature. 2  paroxysmal Specifically In geology: Relating to or produced by a violent convulsion of nature.
Inorganic lead compounds are Group 2A - Probably carcinogenic to humans. American Conference for Governmental Industrial Hygienists (ACGIH): A3 - Confirmed animal carcinogen. Teratogenicity / Embryotoxicity: DEVELOPMENTAL HAZARD. May harm the unborn child. Known to cause: learning disabilities, effects on behaviour.
When both oxygen and water are present, metallic lead is converted to lead hydroxide (Pb(OH) 2): 2Pb(s)+ O 2 (g) + 2H 2 O(l) -> 2 Pb(OH) 2 (s) Solubility of lead and lead compounds. Elementary lead does not dissolve in water under normal conditions (20 o C, and pressure = 1 bar). It may however occur dissolved in water as PbCO 3 or Pb(CO 3) 2 2-. A well-known example of a water soluble lead compound is lead sugar (lead(II)acetate), which derived its name from its sweet nature. Lead frequently binds to sulphur in sulphide form (S 2-), or to phosphor in phosphate form (PO 4 3-).