Follow up of workers previously exposed to silver solder containing cadmium.

Abstract

Objectives-To study longitudinal biological monitoring data on urinary and blood cadmium collected in a small cohort of nine workers who had been brazing for several years with solders containing cadmium. Methods-Cadmium was measured by neutron activation analysis in livers and kidneys, and estimates of renal function were carried out in 1983 and 1995. During the intervening period exposure to cadmium was dramatically reduced by local exhaust ventilation control and substitution of the solder containing cadmium. Results-From urinary protein measurements there was evidence within the group of increasing renal tubular damage over the 12 year period, even though exposure to cadmium was dramatically reduced over this period and almost eliminated by 1995. There was no evidence from serum creatinine of decreasing glomerular filtration rate, and the renal tubular handling of calcium, phosphate, or urate had not worsened significantly. Blood and urinary cadmium concentrations reduced significantly over the 12 year period but were still substantial in 1995. Blood cadmium concentrations tended to reflect cadmium body burden in 1995 when exposure had been low for several years, and decreased most significantly during 1983-90. By contrast urinary cadmium concentrations only decreased significantly from about 1990 onwards. Urinary cadmium was not significantly correlated with liver or kidney cadmium concentration in either 1983 or 1995. This may be due to the level of tubular dysfunction in the cohort. Calculated cumulative excretion of cadmium over the 12 year period was substantially greater than the loss of cadmium measured in livers and kidneys and the derived loss in body burden. Reasons for this are discussed. It is possible that in cohorts, where renal damage is apparent, urinary concentrations reflect a substantial component of current exposure rather than stored body losses. Conclusions-The data reinforce the concept that blood cadmium concentrations may not always reflect recent exposure, but may reflect body burden derived from historical exposure depending on the degree of current exposure; and that the decline in urinary and blood cadmium measurements after removal from, or reduction in, exposure will be slow and depend on the historical body burden. (Occup Environ Med 1999;56:553-558)

Cadmium and Lead in Blood in Relation to Low Bone Mineral Density and Tubular Proteinuria

“…The dose estimate most often used for cadmium is urinary cadmium. However, renal damage may lead to a higher excretion of cadmium, as has been shown both in animal (1,5) and in human studies (1,6,25,26). It has been shown that blood cadmium can be a better dose estimate when tubular proteinuria is present (27).…”

“…Urinary cadmium is commonly used to assess body burden of cadmium and has been useful in many studies (4). However, it has been claimed that elevated levels of cadmium in the urine may reflect not only high levels of cadmium dose but also renal damage (1,5,6). Cadmium in blood mainly reflects recent exposure, but it has also been shown to be a good indicator of cadmium body burden (7,8).…”

Impact of occupational cadmium exposure on spirometry, sputum leukocyte count, and lung cell DNA damage among Indian goldsmiths

“…In our previous report, we showed that jewelry manufacturing workers were exposed to occupational Cd-exposure during fabrication of the jewelry products, which produced a marked dose-response relationship with altered lung function [Moitra et al, 2013]. In addition, there is substantial evidence, which had shown pertinent Cd-associated adverse respiratory effects in soldering/brazing activities [Sakurai et al, 1982;Edling et al, 1986;Sorahan et al, 1995;Mason et al, 1999;Panchal and Vaideeswar, 2006;Sethi et al, 2006].…”

“…With chronic Cd-exposure, some reports have identified a strong exposure-response relationship for adverse respiratory effects [Davison et al, 1988;Nemery, 1990;Fuortes et al, 1991;Sorahan et al, 1995;Sorahan and Esmen, 2004;Fireman et al, 2008;Rokadia and Agarwal, 2013], while others have not [Chan et al, 1988;Jakubowski et al, 2004]. However, there are substantial reports, which have demonstrated adverse respiratory effects due to occupational cadmium exposure [Baker et al, 1979;Mason et al, 1999;Panchal and Vaideeswar, 2006;Sethi et al, 2006;Moitra et al, 2013]. Fireman et al [2008] observed that Cd-induced respiratory impairment involved elevated neutrophil infiltration in alveolar bed in induced sputum among a group of welders exposed to heavy metals.…”

Adverse respiratory effects associated with cadmium exposure in small-scale jewellery workshops in India

“…Acute Cd inhalation toxicity from solder brazing has been documented in case reports from silver jewellery making in India 21 22. Subacute to chronic Cd exposure from ‘silver solder’ has been well-recognised in jewellery fabrication and in other industrial brazing applications 23 24. Cd overexposure from gold and silver alloying with Cd has also been reported 25…”