2006). Using in part the same data base, Travier et al. (2002) found significantly raised incidence rates for Hodgkin’s disease and leukaemia (but not for non-Hodgkin’s lymphoma) in female but not in male launderers, dry-cleaners and pressers employed in the laundry, ironing or dyeing industry in both the 1960 and 1970 Swedish censuses and this website followed until 1989. The incidence of cervical cancer was not click here increased in this particular group. In Sweden, PER has been the quantitatively most important agent for dry-cleaning during the second half of the 20th century (Kemikalieinspektionen 1990; Johansen et al. 2005), and

to assess further the potential carcinogenicity of PER, we decided to follow-up a previously assembled, national cohort Selleckchem Stattic of dry-cleaning and laundry workers by cross-linking with the national cancer register. Materials and methods As part of a Scandinavian initiative (Olsen et al. 1990), a nationwide study of pregnancy outcome in dry-cleaning workers, was undertaken in the mid-1980s (Ahlborg 1990a). A questionnaire mailed to all “washing establishments” recorded in the Swedish Postal Address Registry (n = 1,254) yielded a response rate of 37.9%. The questionnaire

called for information about both the establishment (company) and the workers over a period of 11 years (1973–1983). Production volumes and washing techniques were requested as well as details of any chemicals used. No information on PER exposure at the company or individual level was available, but estimates of the proportion of PER and other detergents employed (as reported by the companies over the period of interest) were used as proxy. Names Interleukin-3 receptor and ten-digit personal identity numbers (PINs) of the workers (Ludvigsson et al. 2009), their occupation, dates of hire and termination of employment were also requested. At least one month duration of employment was required for inclusion in the original study. All data were checked for the present study, and unidentifiable subjects

or those not fulfilling original or current inclusion criteria were excluded from the analysis. Data from 14 companies were lost in the process, leaving workers from 461 companies for the study. The size of the companies involved varied from small family businesses to establishments with several hundred employees. Each subject was assigned to one of three exposure categories based on information from the companies: the PER subgroup (genuine dry-cleaners and laundries with a proportion of dry-cleaning with PER only), the Laundry subgroup (laundries only, no PER) or Other (any combination of water, PER, chlorofluorocarbons (typically Freon 113) and sporadic cases of white spirit, naphta or trichloroethylene).