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.
Either hexavalent chromium or trivalent chromium may be used to produce chrome. The electroplating chemicals for both processes are toxic and regulated in many countries. Hexavalent chromium is extremely toxic, so trivalent chrome or tri-chrome tends to be more popular for modern applications.In 2007 hexa-chrome was banned for use on automobiles in Europe.ither hexavalent chromium or trivalent chromium may be used to produce chrome. The electroplating chemicals for both processes are toxic and regulated in many countries. Hexavalent chromium is extremely toxic, so trivalent chrome or tri-chrome tends to be more popular for modern applications.