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Recent case-control studiesIn a study by Berrino et al. (2003), 315 males aged less than 55 years, diagnosed with laryngeal or hypopharyngeal cancer over a 3 – 5 year period in the late seventies to the early eighties in 6 centres in France, Italy, Spain and Switzerland were investigated. Most cases were interviewed, and information on occupational exposures, smoking and alcohol consumption, socio-economic status and diet obtained. Occupational exposures to substances, including formaldehyde, were determined using a job exposure matrix. Cases in each centre were matched by age and sex to a random sample of the general population (819 controls in total). After adjustment for potential confounding factors, such as smoking, alcohol consumption and other occupational exposures (including, wood dust and asbestos), a small increased risk, not statistically significant (OR = 1.3, 95% CI 0.8 – 2.0), was seen for exposure to formaldehyde. Analysis of duration of exposure (any probability) to formaldehyde showed no positive trend (although for 10 – 19 years exposure OR = 2.2, 95% CI 1.2 – 4.2 and OR = 1.3, 95% CI 0.6
In a study by Elci et al. (2003), 940 males diagnosed with laryngeal cancer between 1979 and 1984 at a hospital in Istanbul, Turkey, were investigated. Cases were interviewed and information on occupational history, smoking and alcohol consumption obtained. Occupational exposures to substances, including formaldehyde, were determined using a job exposure matrix. Cases were matched with 1519 males who had other cancers thought not to share similar etiologic factors with laryngeal cancer. After adjustment for potential confounding factors, such as age, smoking and alcohol consumption, no increased risk was seen for formaldehyde exposure. For analysis of the anatomical site of tumour origin, a small non-significant increased risk was only seen for cancers originating in the glottic area (OR = 1.2, 95% CI 0.8 – 2.0). No exposure-response relationship was seen for either intensity or probability of exposure to formaldehyde and cancers originating in the glottic area (or for laryngeal cancers originating in the suparglottic or subglottic area). Hildesheim et al. (2001) investigated occupational exposure to formaldehyde among 375 newly diagnosed cases of nasopharyngeal cancers in two tertiary care hospitals in Taiwan between July 1991 and December 1994. These cases were matched on sex, age and geographical residence to 325 population controls. Data were collected from cases and controls by interviews and questionnaires. Occupational exposures were reviewed (blindly) by an industrial hygienist. A total of 74 cases with formaldehyde exposure were identified. After adjustment for a number of confounding factors, such as socio-demographic characteristics and cigarette smoking, a small non-statistically significant increased risk was seen for nasopharyngeal cancers and exposure to formaldehyde (OR = 1.4, 95% CI 0.93 – 2.2). Additionally, no statistically significant trend was seen for either duration or cumulative exposure to formaldehyde and nasopharyngeal cancers. Similarly, no dose response was observed for analysis of years since first exposure. Exposure to wood dust, with the exception of age at first exposure > 25 years, resulted in greater increased risks than for exposure to formaldehyde, and the authors concluded that exposure to formaldehyde is less clearly linked to nasopharyngeal cancer than wood dust. The study by Hildesheim et al. (2001) also tested blood samples from cases and controls for various anti-Epstein-Barr virus (EBV) antibodies which, the authors report, are associated with nasopharyngeal cancers. Among those seropositive to antibodies for EBV (360 cases, 94 controls), a significantly increased risk was seen for exposure to formaldehyde (OR = 2.7, 95% CI 1.2 - 6.2). However, as with the above analysis, no dose response was seen with increasing duration or cumulative exposure to formaldehyde. In a study by Armstrong et al. (2000), 282 Chinese residents in Malaysia diagnosed with nasopharyngeal carcinomas between January 1987 and June 1992 were investigated. These residents were interviewed about their occupational history, diet, alcohol consumption and tobacco use, and each case matched by age and sex to a Malaysian Chinese control. Following adjustment for potential confounders, no increased risk was found for nasopharyngeal cancers and occupational exposure to formaldehyde. Additionally, no dose response was observed for duration of exposure to formaldehyde and nasopharyngeal carcinomas. However, only 51 of 564 cases reported occupational exposure to formaldehyde, and of these 51 cases only 8 had accumulated exposure > 10 years. Laforest et al. (2000) investigated occupational exposure to formaldehyde among 201 and 296 newly diagnosed cases of (primary) squamous cell hypopharyngeal and laryngeal cancers in men, respectively, reported in 15 French hospitals between January 1989 and April 1991. Information on demographic characteristics, alcohol and tobacco consumption, and lifetime occupational history were obtained through interviews. Occupational exposures were determined using a job exposure matrix. Controls were patients with (primary) cancers at different body sites, in the same or nearby hospitals during the same period and matched by age. After adjustment for potential confounding factors, such as smoking, alcohol consumption and other occupational exposures (including asbestos and man made mineral fibres), a statistically significant trend was seen for hypopharyngeal cancers and the probability of exposure to formaldehyde (Ptrend <0.005, OR = 3.8, 95% CI 1.5 - 9.5 for the highest probability of exposure). No significant trend was noted for these cancers, however, in respect to duration or cumulative exposure to formaldehyde. When cases with a low probability of exposure to formaldehyde were excluded increased risks were observed for exposure to formaldehyde, with a statistically significant trend observed for duration of exposure (P <0.04) and for cumulative level of exposure (p <0.14). Neither the ORs nor any trend suggested an association between formaldehyde exposure and laryngeal cancer. Vaughan et al. (2000) investigated occupational exposure to formaldehyde among 196 newly diagnosed cases of nasopharyngeal cancers reported in five US cancer registries between April 1987 and June 1993. These epithelial cancers were classified into 3 histological groups: 54 cases of undifferentiated and non- keratinising, 118 cases of differentiated squamous cell and 24 cases of unspecified epithelial. A total of 244 community controls were randomly selected and matched by age, gender and cancer registry. Data were collected for cases and controls by telephone interviews. Information on a number of confounding factors, such as history of occupational and chemical exposure, demographic background, medical history, family history of cancer, smoking and alcohol consumption, were collected. Estimates of potential exposure to formaldehyde were carried out on a job-by-job basis by experienced industrial hygienists who were blinded to the status of the subjects. After adjustment for potential confounding factors, no increased risk was seen between potential exposure to formaldehyde and undifferentiated and non-keratinising carcinomas. Excluding these histological cancer types, a statistically significant trend was seen between nasopharyngeal cancers and both exposure duration (Ptrend = 0.014, OR = 2.7, 95% CI 1.2 - 6.0 for the top exposure duration of > 18 years) and cumulative exposure (Ptrend = 0.033, OR = 3.0, 95% CI 1.3 - 6.6 for the greatest cumulative exposure of > 1.10 ppm years), for 25 and 24 cases, respectively, that were considered to have had a possible, probable or definitive exposure to formaldehyde. However, when cases with a low probability of exposure to formaldehyde were omitted the significance of the trend decreased for both duration (Ptrend = 0.069) and cumulative exposure (Ptrend = 0.13). While for definitive exposure to formaldehyde, although highly significant trends were reported for duration and cumulative exposure (Ptrend <0.001), this is based on only 10 available cases. These ORs for formaldehyde were essentially unaffected by adding exposure to wood dust to the models. Directory: data -> assets -> word doc -> 0006 word doc -> Commonwealth of Australia 2002 word doc -> Commonwealth of Australia 2000 word doc -> Priority Existing Chemical word doc -> Rail safety news issue 6 – October 2011 word doc -> Review of Multiple Chemical Sensitivity: Identifying 0006 -> Board Endorsed October 2009 amended 13-09-11 with extra units 0006 -> Rt Hon Andrew Lansley cbe mp secretary of State for Health 0006 -> Environmental Approvals Application Form Use this form Download 5.77 Mb. Share with your friends:
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