THE EFFECTS OF SIX WEEKS FEEDING WITH DIETS LOW IN METHIONINE, CHOLINE, METHIONINE AND CHOLINE, OR PROTEINS ON THE BIOTRANSFORMATION AND RETENTION OF 76AS-LABELLED ARSENITE (0.4 MG AS/KG BODY WEIGHT) IN RABBITS HAVE BEEN STUDIED. ALL TEST DIETS CAUSED ADEPRESSION OF THE METHYLATION OF THE ADMINISTRATED ARSENITE, AND A SIGNIFICANTLY DECREASE IN THE URINARY EXCRETION OF 76AS-DIMETHYLARSINIC ACID, THE MAIN METABOLITE OF INORGANIC ARSENIC. THIS GAVE RISE TO AN INCREASED RETENTION OF ARSENIC IN THE TISSUES, AT 3 DAYS AFTER THE ARSENITE ADMINISTRATION MAINLY IN THE LIVER KIDNEYS, LUNGS AND TESTES. THIS EFFECT WAS MOST MARKED IN RABBITS FED A DIET DEPRIVED IN BOTH METHIONINE AND CHOLINE. THE TEST DIETS ALSO CAUSED A SPECIFIC INCREASE OF THE ARSENIC CONCENTRATION IN THE LIVER MICROSOMES, WHICH DOES NOT OCCUR FOLLOWING CHEMICALLY INDUCED DEPRESSION OF THE ARSENIC METHYLATION. THE RESULTS INDICATE THAT SUBJECTS WITH A LOW NUTRITIONAL STATUS, ESPECIALLY LOW PROTEIN INTAKES, HAVE A LOWER CAPACITY OF METHYLATING AND THEREBY DETOXIFYING INORGANIC ARSENIC, WHICH WOULD RENDER THEM MORE SENSITIVE TO ARSENIC EXPOSURE. KEY WORDS: ARSENITE, BIOTRANSFORMATION, METHYLATION, MALNUTRITION, METHIONINE, CHOLINE

MARAFANTE Erminio; 

1995-03-15

JRC4202

https://publications.jrc.ec.europa.eu/repository/handle/JRC4202,