Exposure-effect relationship of platinum salt allergy in a catalyst production plant: conclusions from a 5-year prospective cohort study.
BACKGROUND
There is a high incidence of occupational asthma and rhinitis caused by platinum (Pt) salts in precious-metal refineries.


OBJECTIVE
We sought to assess exposure to Pt salts and the incidence of Pt salt allergy in a catalyst production plant.


METHODS
A 5-year prospective cohort study was performed in 159 catalyst production workers (94.6% of recruited), 50 craftsmen (92. 6% of recruited), and 66 control subjects (76.7% of recruited) at yearly intervals. Subjects were assigned to exposure categories of high levels of Pt (n = 115), persistently low levels of Pt (n = 51), intermittently low levels of Pt (n = 61), or no Pt (n = 48) after the initial survey according to job title and job location. Skin prick test conversion from a negative response to a 4 mm or larger wheal response with a 10(-2) mol/L hexachloroplatinic acid solution was chosen as the outcome variable.


RESULTS
Exposure assessment of airborne Pt and Pt in the serum of workers demonstrated clear differences between exposure categories. The threshold limit value of 2 microg/m(3) for soluble Pt was exceeded in 3 (4%) of 78 measurements. Thirteen subjects assigned to high exposure showed skin test conversion, and new allergic symptoms were associated with exposure. Among the high-exposure category, the incidence rate of skin prick test conversion was 5.9 per 100 person-years for newly employed subjects (n = 79) and 2.1 per 100 person-years for those who had already been employed at the time of the initial survey (n = 36). A predicting factor for skin test conversion in highly exposed subjects was smoking status (relative risk, 3.9; 95% confidence interval, 1.6-9.7) but not atopy or bronchial hyperresponsiveness.


CONCLUSIONS
Sensitization to Pt salts may develop in workers of catalyst production plants. Both the exposure to Pt salts and the incidence of Pt salt allergy were lower compared with reported data from precious-metal refineries.
Merget
R
R
Department of Internal Medicine, Division of Pneumonology, Allergology and Sleep Medicine, University Hospital Bergmannsheil, Bochum, Germany.
Kulzer
R
R
Dierkes-Globisch
A
A
Breitstadt
R
R
Gebler
A
A
Kniffka
A
A
Artelt
S
S
Koenig
H P
HP
Alt
F
F
Vormberg
R
R
Baur
X
X
Schultze-Werninghaus
G
G
D000328:Adult; D001249:Asthma / Q000139:chemically induced* / Q000276:immunology / Q000503:physiopathology; D016535:Bronchial Hyperreactivity / Q000139:chemically induced / Q000276:immunology; D015331:Cohort Studies; D004306:Dose-Response Relationship, Immunologic; D005260:Female; D006801:Humans; D019570:Inhalation Exposure; D008297:Male; D008669:Metallurgy; D015999:Multivariate Analysis; D009784:Occupational Diseases / Q000139:chemically induced* / Q000276:immunology / Q000503:physiopathology; D017671:Platinum Compounds / Q000009:adverse effects* / Q000276:immunology; D011446:Prospective Studies; D012130:Respiratory Hypersensitivity / Q000139:chemically induced* / Q000276:immunology / Q000503:physiopathology; D012221:Rhinitis, Allergic, Perennial / Q000139:chemically induced* / Q000276:immunology / Q000503:physiopathology; D012492:Salts / Q000009:adverse effects / Q000276:immunology; D012882:Skin Tests
D017671:Platinum Compounds; D012492:Salts