revised final - Agency for Toxic Substances and Disease Registry ...

MERCURY
Renal Effects
2. HEALTH EFFECTS
Metallic Mercury. The kidney is a sensitive target organ of toxicity following inhalation exposure to
metallic mercury. This sensitivity may be, in part, because of the relatively high accumulation of mercury in
the kidneys. Acute high-concentration inhalation exposure in humans has resulted in effects ranging from
mild transient proteinuria or s syndrome has been reported light changes in urinary acid excretion (Bluhm et
al. 1992b; Soni et al. 1992); to frank proteinuria, hematuria, and/oliguria (Campbell 1948; Hallee 1969;
Snodgrass et al. 1981); to acute renal failure with degeneration or necrosis of the proximal convoluted
tubules (Campbell 1948; Jaffe et al. 1983; Kanluen and Gottlieb 1991; Rowens et al. 1991). Actual exposure
concentrations are unknown in these cases, but urinary mercury excretion as high as 59–193 µg/hour has
been reported (Bluhm et al. 1992b).
A nephrotic in two case studies of intermediate-duration exposure (Agner and Jans 1978; Friberg et al.
1953). In one report, the exposure was to a spill in the home (Agner and Jans 1978); in the other, the
exposure was occupational (Friberg et al. 1953). The nephrotic syndrome was characterized by edema and
proteinuria with albumin and hyaline casts in the urine. These changes usually abated within a few months
following termination of exposure. Among a group of 10 patients who reported adverse effects associated
with dental amalgams (the route of exposure in dental amalgams is probably a mixture of inhalation
exposure to mercury vapor released from the amalgams, absorption of the vapor through the oral mucosa,
and ingestion), a decrease in the ability to concentrate the urine and elevated urinary albumin were observed
(Anneroth et al. 1992). Removal of one amalgam resulted in a significant decrease in urinary albumin (it is
unknown whether other amalgams remained). In a study of renal function in 10 healthy volunteers having
an average of 18 amalgam-filled tooth surfaces both before and after amalgam removal (Sandborgh-Englund
and Nygren 1996), no signs of renal toxicity were found in conjunction with mercury released from the
amalgam fillings. Although plasma mercury levels increased significantly one day after removal of the
fillings (all removals were accomplished in one dental session), glomerular filtration rates were similar both
before and after mercury exposure (amalgam removal). Blood, plasma, and urine mercury concentrations
were significantly lower 60 days after amalgam removal.
The results from a number of studies show renal toxicity in workers chronically exposed to mercury vapor
(Barregard et al. 1988; Bernard et al. 1987; Buchet et al. 1980; Cardenas et al. 1993; Danziger and
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