Urinary excretion of inorganic arsenic and its metabolites after repeated ingestion of sodium metaarsenite by volunteers

  • J. P. Buchet
  • R. Lauwerys
  • H. Roels
Original Papers


Arsenic (125, 250, 500 or 1000 μg as NaAsO2) was administered orally once a day for five consecutive days to 4 volunteers who refrained from eating marine organisms during the experiment. Urine was collected during 24-h periods starting one day before the first administration and up to 14 days later. The following determinations were performed: total arsenic, inorganic arsenic (As;), monomethyl arsenic (MMA) and dimethylarsinic (DMA) acids. In each case, the sum of As;, MMA and DMA approximated very closely the urinary concentration of total arsenic determined after mineralisation of the urine sample. It was concluded that these arsenicals are the only metabolic forms of arsenic following absorption of inorganic arsenic. Since a steady state in the urinary excretion of arsenic is reached within 5 days, our results demonstrated that at equilibrium, the total amount of arsenic excreted in urine per day amounts to 60% of the ingested dose. Speciation of the arsenic metabolites in urine indicated that the arsenic methylation capacity of the human body was not yet saturated, even with an oral daily dose of 1000 μg As for 5 days. However, when the administration of arsenic was stopped, the biological half life of arsenic in urine increased slightly with the dose (from 39 h at 125 μg to 59 h at 1000 μg). Determination of inorganic arsenic, MMA and DMA in urine appears to be the method of choice for the biological monitoring of workers exposed to inorganic arsenic since these measurements are not influenced by the presence of organoarsenicals from marine origin. From the linear relationship found in this study between arsenic administered and that excreted in urine, it was estimated that a time-weighted average exposure of 50 μg As/m3 would lead to an average urinary excretion of 220 μg As (sum of Asi, MMA and DMA) per gram creatinine.

Key words

Inorganic arsenic Human metabolism 


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  1. Buchet JP, Lauwerys R, Roels H (1980) Comparison of several methods for the determination of arsenic compounds in water and in urine. Int Arch Occup Environ Health 46:11–29Google Scholar
  2. Buchet JP, Lauwerys R, Roels H (1981) Comparison of the urinary excretion of arsenic metabolites after a single oral dose of sodium arsenite, monomethylarsonate or dimethylarsinate in man. Int Arch Occup Environ Health 48:71–79Google Scholar
  3. Carlsson G (1976) Correlation between industrial arsenic exposure and excretion in urine. Examination Report. Stockholm, the National Board of Industrial Safety, Department of Occupational HealthGoogle Scholar
  4. Crecelius E (1977) Changes in the chemical speciation of arsenic following ingestion by man. Environ Health Perspec 19:147–150Google Scholar
  5. Diem K, Lentner C (1972) In “Tables Scientifiques Documenta Geigy”. Ciba Geigy (ed). Basel, SwitzerlandGoogle Scholar
  6. Gollop B, Glass W (1979) Urinary arsenic levels in timber treatment operators. New Zealand Med J 89:11–13Google Scholar
  7. Mappes R (1977) Versuche zur Ausscheidung von Arsen im Urin. Int Arch Occup Environ Health 40:267–272Google Scholar
  8. Pershagen G, Vahter M (1979) In “Arsenic—A toxicological and epidemiological appraisal”. Rapport SNVPM 1128 Naturvårdsverket. Departments of Environmental Hygiene of the Karolinska Institute and the National Swedish Environment Protection Board, Stockholm, SwedenGoogle Scholar
  9. Pinto SS, Varner MO, Nelson MA, Labbe AL, White LD (1976) Arsenic trioxide absorption and excretion in industry. J Occup Med 18:677–680Google Scholar
  10. Smith TJ, Crecelius EA, Reading JC (1977) Airborne As exposure and excretion of methylated As compounds. Environ Health Perspect 19:89–93Google Scholar
  11. Tarrant R, Allard J (1972) Arsenic levels in urine of forest workers applying silvicides. Arch Environ Health 24:277–280Google Scholar
  12. Valentine J, Kang HK, Spivey G (1979) Arsenic levels in human blood, urine, and hair in response to exposure via drinking water. Environ Res 20:24–32Google Scholar
  13. Wagner SL, Weswig P (1974) Arsenic in blood and urine of forest workers as indices of exposure to cacodylic acid. Arch Environ Health 28:77–79Google Scholar

Copyright information

© Springer-Verlag 1981

Authors and Affiliations

  • J. P. Buchet
    • 1
  • R. Lauwerys
    • 1
  • H. Roels
    • 1
  1. 1.Unité de Toxicologie Industrielle et MédicaleUniversité de LouvainBruxellesBelgium

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