Table 6.3   Summary of methods for bioaccessibility testing Method PBET Mass- balance Digestive tract model DIN 19738 RIVM GJST PREP IVG SHIME TIM Reference Conditions /81;82/ /83/ /84/ /85/ /86/ /52/ /87/ /88/ /76/ /76/ Target conta- minants metals metals metals and organic con- taminants metals and or- ganic conta- minants metals and organic con- taminants metals metals metals metals metals Target matrices soils, mine wastes soils soils contaminated soils, wastes, sediments soils soils soils soils soils soils Resolution in compartment and time stomach and intestine de- termined se- parately and with time resolution stomach and intestine separately none none none none none stomach and intestine separately none stomach and intestine de- termined se- parately and with time resolution Oxygen access in test no, argon purge yes yes yes yes yes yes no, argon purge yes yes L/S - 160 - 15¹⁹ 15 - - - - 5 Solution - mucin, urea, phosphate buffer, sodi- um, calcium and potas- sium chloride pH = 5,5 - mucin, amy- lase, urea, uric acid, phos- phate and bicarbonate buffers, calci- um, potassi- um and sodi- um chloride, sodium sul- phate, sodium thiocyanate pH = 6,4 mucin, amy- lase, urea, uric acid, phos- phate buffer, sodium hydro- xide, potassi- um and sodi- um chloride, sodium sul- phate, sodium thiocyanate pH = 6,5 - - - - not specified pH = 5,0 Time - 5 seconds - 30 minutes 5 minutes - - - - 5 minutes Mouth and esophagus Temperature - ambient - 37 °C 37 °C - - - - 37 °C Method PBET Mass- balance Digestive tract model DIN 19738 RIVM GJST PREP IVG SHIME TIM L/S 100 2.000 105-120 50 37,5 22,2 30 150 2,5 25 Solution hydrochloric acid, pepsin, citrate, ma- late, acetic acid pH = 1,3²⁰ hydrochloric acid, pepsin, sodium chloride pH not specified hydrochloric acid, sodium chloride, pep- sin, mucin⁸, whole milk powder pH = 2,0 hydrochloric acid, phos- phate buffer, sodium and potassium chloride, pep- sin, mucin, whole-milk powder²¹ pH = 2 hydrochloric acid, phos- phate buffer, calcium, am- monium, so- dium and po- tassium chlo- ride, glucose, glucuronic acid, urea, glucosamine, serum albumi- ne, pepsin, mucin pH = 1,07 ± 0,07 acetic acid, hydrochloric acid pH = 6 → 2 baby food, hydrochloric acid, phosphate buffer pH = 2,0 hydrochloric acid, sodium chloride, pepsin, dough pH = 1,8 baby food, cream, pectin, mucin, starch, cellobiose, proteose, peptone pH = 4,0 not specified in detail, li- pase, pepsin pH = 5,0 → 2,0 Time 1 hour 2 hours 2 hours 2 hours 2 hours 2,67 hours 1 hour 1 hour 3 hours 1,5 hour Stomach Temperature 37 °C 37 °C 37 °C 37 °C 37 °C 37 °C 37 °C 37 °C 37 °C 37 °C L/S 100 4.400 120 100 97,5 - 40 150 4,0 46 Solution sodium bicar- bonate, bile salts, pancreatin pH = 7,0 sodium bicarbonate pH not specified sodium bi- carbonate, trypsin, pan- creatin, bile pH = 7,0 potassium, calcium and magnesium chloride, bicarbonate buffer, trypsin, pancreatin, bile, urea pH = 7,5 hydrochloric acid, potas- sium, sodium, calcium and magnesium chloride, phosphate and bicarbo- nate buffers, serum albu- mine, lipase, pancreatin, bile, urea pH = 8,0 ± 0,2 - sodium carbonate, metallo- thionein pH = 6,9 ± 0,1 sodium bi- carbonate, pancreatin, bile pH = 5,5 sodium bi- carbonate, bile, pancre- atin pH = 6,5 not specified in detail, bile, phosphate, pancreatin pH = 6,5 → 7,2 Time 3 hours 2 hours 6 hours 6 hours 2 hours - 1,5 hours 1 hour 5 hours 6 hours Small intestine Temperature 37 °C 37 °C 37 °C 37 °C 37 °C - 37 °C 37 °C 37 °C 37 °C