Exposure assessment for a nested case-control study of lung cancer among European asphalt workers.
OBJECTIVE
Development of a method for retrospective assessment of exposure to bitumen fume, bitumen condensate, organic vapour, polycyclic aromatic hydrocarbons, and co-exposures to known or suspected lung carcinogens for a nested case-control study of lung cancer mortality among European asphalt workers.


METHODS
Company questionnaires and structured questionnaires used in interviews and industry-specific job-exposure matrices (JEMs) were elaborated and applied. Three sources of information were eventually used for exposure assessment and assignment: (i) data obtained in cohort phase, (ii) data from living subjects, next-of-kin, and fellow-workers questionnaires, and (iii) JEMs for bitumen exposure by inhalation and via skin and co-exposures to known or suspected lung carcinogens within and outside cohort companies. Inhalation and dermal exposure estimates for bitumen were adjusted for time trends, time spent in a job, and other determinants of exposure (e.g. oil gravel paving). Clothing patterns, personal protective devices, and personal hygiene were taken into consideration while estimating dermal exposure.


RESULTS
Occupational exposures could be assessed for 433 cases and 1253 controls for relevant time periods. Only 43% of work histories were spent inside original asphalt and construction companies. A total of 95.8% of job periods in cohort companies could be coded at a more detailed level. Imputation of work time and 'hygienic behaviour' multipliers was needed for <10% of work history years. Overall, downward trends in exposure were present and differences existed between countries and companies. As expected, correlations were strongest (r > 0.7) among bitumen-related agents, while correlations between coal tar, bitumen-related agents, and established lung carcinogens were weaker (r < 0.4).


CONCLUSIONS
A systematic and detailed approach was developed to estimate inhalation and dermal exposure for a nested case-control study among asphalt workers.
Agostini
Michela
M
Institute of Risk Assessment Sciences, University of Utrecht, the Netherlands.
Ferro
Gilles
G
Olsson
Ann
A
Burstyn
Igor
I
De Vocht
Frank
F
Hansen
Johnni
J
Lassen
Christina Funch
CF
Johansen
Christoffer
C
Kjaerheim
Kristina
K
Langard
Sverre
S
Stucker
Isabelle
I
Ahrens
Wolfgang
W
Behrens
Thomas
T
Lindbohm
Marja-Liisa
ML
Heikkilä
Pirjo
P
Heederik
Dick
D
Portengen
Lützen
L
Shaham
Judith
J
Boffetta
Paolo
P
Kromhout
Hans
H
D000368:Aged; D000395:Air Pollutants, Occupational / Q000032:analysis*; D000465:Algorithms; D002273:Carcinogens / Q000032:analysis; D016022:Case-Control Studies; D015331:Cohort Studies; D060389:Construction Industry / Q000706:statistics & numerical data*; D005060:Europe / Q000453:epidemiology; D006801:Humans; D006838:Hydrocarbons; D019570:Inhalation Exposure / Q000706:statistics & numerical data; D008175:Lung Neoplasms / Q000139:chemically induced / Q000401:mortality*; D008297:Male; D009784:Occupational Diseases / Q000139:chemically induced / Q000401:mortality*; D016273:Occupational Exposure / Q000706:statistics & numerical data*; D009790:Occupations / Q000706:statistics & numerical data; D011084:Polycyclic Aromatic Hydrocarbons / Q000032:analysis; D015995:Prevalence; D011482:Protective Devices / Q000706:statistics & numerical data; D012867:Skin / Q000737:chemistry; D017592:Skin Care / Q000706:statistics & numerical data; D011795:Surveys and Questionnaires; D013997:Time Factors
D000395:Air Pollutants, Occupational; D002273:Carcinogens; D006838:Hydrocarbons; D011084:Polycyclic Aromatic Hydrocarbons; C006647:asphalt