US EPA

2307570 

Journal Article 

PHAGOCYTIC-CELLS AS A CONTRIBUTOR TO IN-VIVO DEGRADATION OF ALKYL MERCURY 

Suda, I; Suda, M; Hirayama, K 

1993 

Yes 

Bulletin of Environmental Contamination and Toxicology
ISSN: 0007-4861
EISSN: 1432-0800 

NIOSH/00215484 

51 

3 

394-400 

English 

8219595 

WOS:A1993LL14100011 

The role of phagocytic blood cells in degrading organic mercury was investigated. Male Wistar-rats were administered 10mg/kg methylmercuric-chloride (115093) (MMC) or ethylmercuric-chloride (107277) (EMC) orally. They were killed 24 hours later. Blood samples were separated into the cellular and plasma fractions and analyzed for organic and inorganic mercury (7439976). The cellular fraction was fractionated into the erythrocytes, mononuclear leukocytes (MNLs), and polymorphonuclear leukocytes (PMNs). More than 90% of the mercury in the total cellular fraction was present as organic mercury after either MMC or EMC treatment. About 0.9% of the mercury in the cellular fraction after MMC treatment and 1.6% after EMC treatment was present as inorganic mercury. When examined by cell type, most of the mercury in the cellular fraction was present in the erythrocytes as organic mercury. Following treatment with MMC, 1.8% of the total cellular mercury content was present as inorganic mercury in the MNLs and 6.2% in the PMNs. Following EMC treatment, 4.7% of the total cellular mercury was present as inorganic mercury in the MNLs and 11.1% in the PMNs. Male Wistar-rats were administered 10mg/kg MMC or EMC orally or intravenously. Twenty four hours later, the peritoneal PMNs were obtained following glycogen stimulation. The PMNs were cultured in the presence or absence of 10 nanograms per milliliter phorbol-myristate-acetate (PMA) for 8 hours. PMN aliquots were taken at 2 hour intervals and analyzed for inorganic mercury. Initially, PMNs from EMC treated rats contained high concentrations of inorganic mercury after either oral or intravenous administration. Very little inorganic mercury was found in PMNs from MMC treated rats. The concentration of inorganic mercury increased with time in PMNs from both MMC and EMC treated rats. The rate of increase was significantly faster in PMNs from EMC treated rats. PMA significantly increased the rate of inorganic mercury formation in PMNs from EMC treated rats. The authors conclude that phagocytic cells, especially PMNs, can degrade organic mercury to inorganic mercury in-vivo.