Mercury disposition in suckling rats: comparative assessment following parenteral exposure to thiomersal and mercuric chloride.
Due to the facts that thiomersal-containing vaccine is still in use in many developing countries, and all forms of mercury have recognised neurotoxic, nephrotoxic, and other toxic effects, studies on disposition of ethylmercury and other mercury forms are still justified, especially at young age. Our investigation aimed at comparing mercury distribution and rate of excretion in the early period of life following exposure to either thiomersal (TM) or mercuric chloride (HgCl₂) in suckling rats. Three experimental groups were studied: control, TM, and HgCl₂, with 12 to18 pups in each. Both forms of mercury were administered subcutaneously in equimolar quantities (0.81 μmol/kg b.w.) three times during the suckling period (on the days of birth 7, 9, and 11) to mimic the vaccination regimen in infants. After the last administration of TM or HgCl₂, total mercury retention and excretion was assessed during following six days. In TM-exposed group mercury retention was higher in the brain, enteral excretion was similar, and urinary excretion was much lower compared to HgCl₂-exposed sucklings. More research is still needed to elucidate all aspects of toxicokinetics and most harmful neurotoxic potential of various forms of mercury, especially in the earliest period of life.
Analytical Toxicology and Mineral Metabolism Unit, Institute for Medical Research and Occupational Health, Ksaverska Cesta 2, P.O. Box 291, HR-10001 Zagreb, Croatia.
Maja
M
Blanuša
Tatjana
T
Orct
Maja
M
Vihnanek Lazarus
Ankica
A
Sekovanić
Martina
M
Piasek
D000818:Animals; D000833:Animals, Suckling; D007263:Infusions, Parenteral; D008627:Mercuric Chloride / Q000008:administration & dosage* / Q000633:toxicity*; D008628:Mercury / Q000097:blood / Q000378:metabolism* / Q000652:urine; D009928:Organ Specificity; D051381:Rats; D017208:Rats, Wistar; D013849:Thimerosal / Q000008:administration & dosage* / Q000633:toxicity*
D013849:Thimerosal; D008627:Mercuric Chloride; D008628:Mercury