text: silicate concentration in lake biwa?   the environmental quality standards relating to "human health items" item standard cd (cadmium) 0.01mg/l or less cn (cyanogen) nd pb (lead) 0.01mg/l or less cr6+ (hexavalent chromium ) 0.05mg/l or less as (arsenic) 0.01mg/l or less t-hg (total mercury) 0.0005mg/l or less alkyl hg (alkyl mercury) nd pcb (polychlorinated biphenyl) nd ch2cl2 (dichloromethane) 0.02mg/l or less ccl4 (carbon tetrachloride) 0.002mg/l or less 1,2-c2h4cl2 (1,2-dichloroethane) 0.004mg/l or less 1,1-c2h2cl2 (1,1-dichloroethylene) 0.02mg/l or less cis-1,2-c2h2cl2 (cis-1,2-dichloroethylene) 0.04mg/l or less 1,1,1-c2h3cl3 (1,1,1-trichloroethane) 1mg/l or less 1,1,2-c2h3cl3 (1,1,2-trichloroethane) 0.006mg/l or less c2hcl3 (trichloroethylene) 0.03mg/l or less c2cl4 (tetrachloroethylene) 0.01mg/l or less 1,3-c3h6cl2 (1,3-dichloropropane) 0.002mg/l or less -r2ncs (thiuram) 0.006mg/l or less simazine (2-chloro-4,6-bis-1,3,5-triazine) 0.003mg/l or less benthiocarb (s-4-chlorobenzyl diethylthiocarbamate) 0.02mg/l or less benzene 0.01mg/l or less se (selenium) 0.01mg/l or less  that's all i can find.  http://www.pref.shiga.jp/biwako/koai/english/eng_top.htm