Registration Dossier

Administrative data

Endpoint:
basic toxicokinetics in vivo
Type of information:
experimental study
Adequacy of study:
supporting study
Reliability:
2 (reliable with restrictions)
Rationale for reliability incl. deficiencies:
data from handbook or collection of data

Data source

Reference
Reference Type:
publication
Title:
Tolerable upper intake levels for vitamins and minerals
Author:
EFSA
Year:
2006

Materials and methods

Objective of study:
absorption
distribution
excretion
toxicokinetics
Principles of method if other than guideline:
citation of a summarizing review
GLP compliance:
not specified

Test material

Reference
Name:
Unnamed
Type:
Constituent
Radiolabelling:
not specified

Results and discussion

Preliminary studies:
Total body potassium is estimated to be approximately 135 g in a 70 kg adult man. Extracellular potassium (circa 2% of body pool) is important for regulation the membrane potential of the cells and thus for nerve and mscle function, blood pressure regulation, ...
Potassium also participates in the acid-base balance. 98% of the potassium in the body is found in the cells, where it is the main intracellular cation.
The absorption of potassium is effective and about 85-90% of dietary potassium is absorbed from the gut. The potassium balance is primarily regulated by renal excretion in urine.
The concentration of potassium in plasma is tightly regulated within a narrow range of about 3.5 to 5 mmol/L. The body is able to accommodate a high intake of potassium, without any substantial change in plasma concentration by synchronized alterations in both renal and extra-renal handling, with potassium either being excreted in the urine or taken up into cells.

Applicant's summary and conclusion

Conclusions:
Interpretation of results : no bioaccumulation potential based on study results
Potassium is an essential nutrient involved in fluid, acid and electrolyte balance and is required for normal cellular function. Dietary deficiency of potassium is very uncommon due to the widespread occurrence of potassium in foods. Available evidence suggests that potassium can modulate blood
pressure and increasing dietary potassium intake is associated with lower blood pressure. However, the available data are insufficient to establish a safe upper intake level for potassium. Based on estimates of current potassium intakes in European countries, the risk of adverse effects from potassium intake from food sources is considered to be low for the generally healthy population (children and adults). The average intake in adults from the diet is 3-4 g and the intake generally does not exceed 5-6 g per day. Total body potassium is estimated to be approximately 135 g in a 70 kg adult man.
Extracellular potassium (circa 2% of body pool) is important for regulation the membrane potential of the cells and thus for nerve and mscle function, blood pressure regulation, ...
Potassium also participates in the acid-base balance. 98% of the potassium in the body is found in the cells, where it is the main intracellular cation.
The absorption of potassium is effective and about 85-90% of dietary potassium is absorbed from the gut. The potassium balance is primarily regulated by renal excretion in urine.
The concentration of potassium in plasma is tightly regulated within a narrow range of about 3.5 to 5 mmol/L. The body is able to accommodate a high intake of potassium, without any substantial change in plasma concentration by synchronized alterations in both renal and extra-renal handling, with potassium either being excreted in the urine or taken up into cells.
Daily intakes of potassium from the habitual diet generally do not exceed 5-6 g/day and has not been associated with any negative effects in healthy individuals. Elderly people may be more vulnerable to potassium toxicity due to reduced physiological reserve in renal function.