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16
CH3041
SUBACUTE
BIOASSAYS
•Mammalian toxicology often uses LD50 data obtained by PAST measurements on rats.
• Sub-lethal and reversible effects occur for
organisms at low doses & there is a margin of safety for chemicals used as drugs.
organisms at low doses & there is a margin of safety for chemicals used as drugs.
• Non-lethal
responses may be used,
ED50 = 50% response; EC50 conc. ® 50% response
ED50 = 50% response; EC50 conc. ® 50% response
eg. tumour risk assessed
against dietary dose
aflatoxin (peanut mold) liver
ppb
FDA 15 ppb
MDL
1 ppb
saccharin bladder
