Tolerable daily intake

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Tolerable daily intake (TDI) refers to the daily amount of a chemical contaminant that has been assessed safe for human being exposure on long-term basis (usually whole lifetime). [1] TDI specifically occurs to chemicals that humans are exposed to unintentionally or as a contaminant, [1] where acceptable daily intake refers to chemicals that are intentional added. [2] TDI is generally written as a value of exposure (eg in milligrams) per kilogram (kg) body weight. [3] Both ADI and TDI are usually assessed based on animal experiments, and it is most often hundreds of times lower than the dose causing no observable adverse effect (NOAEL) in the most sensitive tested animal species. [2] [4] Because the confounding factors (safety factors) may vary depending on the quality of data and the type of adverse effect, TDI values are not good estimates of the harmfulness of chemicals, and must be considered administrative tools to set allowable limits for chemicals, rather than scientific measures. The threshold limit value (TLV) of a chemical substance is a level to which it is believed a worker can be exposed day after day for a working lifetime without adverse effects.

Contents

Examples of Tolerable Daily Intake

World Health Organization

The World Health Organization (WHO) has introduced a TDI for melamine as 0.2 milligrams (mg)/kg body weight as of 2008. [5] Similarly the established TDI range for dioxin according to WHO is 1-4 picograms toxic equivalency/kg body weight as of 1998. [6] WHO's provisional maximum tolerable daily intake for all sources of iodine combined is 0.017 mg/kg body weight. [7]

See also

Recommended daily allowance

Tolerable weekly intake

Acceptable daily intake

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References

  1. 1 2 "tolerable daily intake | EFSA". www.efsa.europa.eu. Retrieved 2024-11-15.
  2. 1 2 Faustman, Elaine M.; Omenn, Gilbert S. (2001). "Risk assessment". In Klaassen, Curtis D. (ed.). Casarett & Doull's Toxicology: The Basic Science of Poisons (6th ed.). New York: McGraw-Hill. pp.  92–4. ISBN   978-0-07-134721-1.
  3. Government of Canada, Public Services and Procurement Canada. "Information archivée dans le Web" (PDF). publications.gc.ca. Retrieved 2024-11-15.
  4. Renwick, A. G. (1999). "Toxicokinetics". In Ballantyne, Bryan; Mars, Tore; Syversen, Timothy (eds.). General and Applied Toxicology (2nd ed.). London: MacMillan Reference. pp. 91–2. ISBN   978-1-56159-242-5.
  5. "Experts set tolerable level for melamine intake". www.who.int. Retrieved 2024-11-15.
  6. van Leeuwen, F. X.; Feeley, M.; Schrenk, D.; Larsen, J. C.; Farland, W.; Younes, M. (2000). "Dioxins: WHO's tolerable daily intake (TDI) revisited". Chemosphere. 40 (9–11): 1095–1101. doi:10.1016/s0045-6535(99)00358-6. ISSN   0045-6535. PMID   10739051.
  7. "WHO | JECFA". apps.who.int. Retrieved 2024-11-15.