Table 2.2. Cohort studies of arsenic exposure and cancer

Transcription

1 Table.. Cohort studies of arsenic exposure and cancer Relative risk or SMR (9% Enterline (987b) 8 copper smelters in US, male white workers in 8 US copper smelters who worked for at least years between January 9 to December 97 Employment records abstracted. Arsenic exposure estimated but details of methods unclear. Some smoking information obtained. Arsenic timeweighted exposure (µg/m year) < Relative risk a p=.8 Age Calendaryear Latency Doseresponse driven primarily by ore plant. Interaction with SO explored. Ades and Kazantzis (988) London, UK men born before 9, who worked for at least one year before 97 at a zincleadcadmium smelter and followed through 98. Matched casecontrol pairs from the cohort were used for the analysis. Controls were age and employment date matched. Exposure was assessed based on the measurements by a plant hygienist. Arsenic present as impurity in the ores at.% average. Exposure to arsenic graded as (background), (low, medium, high levels). From 988 arsenic levels averaged µg/m in sinter and 7µg/m in furnace. Exposure level (Background) (Low) (High) Relative risk... Per years employment. Baseline not clear, not adjusted for other exposures. Multiple exposures. Arsenic and lead correlated and either equally strongly associated with lung cancer risk. Exposures in early 98s at 7µg/m

2 Table.. Cohort studies of arsenic exposure and cancer Relative risk or SMR (9% Sobel (988), Michigan, US, 99 8 workers who had worked for at least one month in an arsenical exposure area and did not leave the company prior to 9. The was an extension of a previous by Ott Job classification and arsenic exposure measurement by industrial hygienist by area monitoring data and interviews conducted by veteran manufacturing personnel Buccal cavity and pharynx Digestive system Respiratory system Prostate Bladder Kidney Brain and CNS Leukemia Haemopoeitic system Cancer type All cancer Buccal cavity and pharynx Digestive system Respiratory system Prostate Bladder Kidney Brain and CNS Leukemia Haemopoeitic system Other sites SMR (9% 8 (7) () (877) () (8) 7 () 7 (98) 7 (7) 8 (79) 9 (97) Respiratory cancer By duration of exposure (years) < + 9 (8) 8 (7) (79) By followup interval (888) () By of first arsenic exposure < (9) (7) (7) 9 (8) All cancer By followup interval () 8 (8)

3 Table.. Cohort studies of arsenic exposure and cancer Relative risk or SMR (9% Järup (989) Stockholm, Sweden 9897 to 98 Cohort included 9 male workers employed for at least months from 98 to 97. Data on work history and causes of death were obtained till December, 98. Air arsenic concentrations estimated by industrial hygienist based on measurements, amount of raw As handled, changes in production methods, and information on sick leave owing to etches and gas injuries caused by arsenic. Intensity of exposure (mg/m ) < years of exposure <..<..+ Total 9 years of exposure <..<..+ Total > years of exposure <..<..+ Total 8 7 SMR SMR adj Dose category (mg years/m ) <.. to < to < to < to < to < + Total 7 9 SMR (9% SMR SMR 7 (8) 7 9 (9) 8 8 (98) 9 8 (898) (9) 8 78 (78) (8898) 7 () 79 79

4 Table.. Cohort studies of arsenic exposure and cancer Relative risk or SMR (9% Kusiak et al. (99) Ontario, 9778,8 men who worked in Ontario mines observed between 998. Except for uranium miners, only miners who attended the chest clinic in 9 or later or who had been employed in a dusty job for a minimum of two weeks in mines in Ontario after 9 and a minimum of months in jobs with dust exposure in mining anywhere included in the. Regional values of four typical geographically distinct regions from summary studies. Chemical analytical data from a geochemical database. Weighted arsenic exposure of each employee based on the years of exposure and the level of arsenic in that mine was assessed. Mean index of exposure (% Asy) By exposure to arsenic before 9, lagged by years By exposure to arsenic after 9, lagged by years SMR Exposure estimates based on measurements in the ores. No indication of radon and arsenic interaction.

5 Table.. Cohort studies of arsenic exposure and cancer Relative risk or SMR (9% Enterline (99) Tacoma, Washingto n, men who worked for one or more years during 99 at a copper smelter in Tacoma, Washington; mortality followup 997 updated until 98; includes estimates of exposure for Air arsenic measurements from company annual reports starting in 98 and urinary arsenic measurements identified at the department and individual levels from 98. Urinary arsenic levels were converted to air levels. Respiratory system Cumulative exposure (µg/m year) Total cohort <7 7,999,,999,7,999 8,9,999,,999,+ Hired <9 <7 7,999,,999,7,999 8,9,999,,999,+ 9 8 SMR Different methods of exposure assessment and follow up were used at different time intervals. When environmental arsenic was measured, measurement of low exposure areas was not taken into account. Buccal cancer Hired 9 <7 7,999,,999,7,999 8,9,999,,999, <7 7,999,,999,7,999 8,9,999,,999,

6 Table.. Cohort studies of arsenic exposure and cancer Relative risk or SMR (9% Enterline (99) (contd) Colorectal cancer <7 7,999,,999,7,999 8,9,999,,999, Kidney cancer Bone cancer <7 7,999,,999,7,999 8,9,999,,999, <7 7,999,,999,7,999 8,9,999,,999,

7 Table.. Cohort studies of arsenic exposure and cancer Relative risk or SMR (9% Bulbulyan (99) Voskresens k, Moscow, Russia, 999 Fertilization plant workers employed at least years between 998 in production or other services, 9 men, 97 women, 89 person years from 9 to 99, lost to follow up Arsenic exposure burden, Industrial hygiene survey No arsenic measurements Stomach cancer (), cancer () Cumulative exposure level (unityear) Stomach cancer Unexposed 9 9 cancer Unexposed Relative risk (9%.. (..9).8 (..).7 (.7.).9 (.9.)..9 (..).8 (..).9 (..). (..) Model estimates for arsenic index only. Findings insignificant without significant trend. Qiao, (997) Yunnan, China, 9799 tin miners:. At least years old. Confirmed history of at least years underground and/or smelting experience. Current or retired YTC workers. No proven active or verified history of previous malignancy (except non melanoma skin cancer). Consenting At the time of the entry cohort was interviewed by a standardized questionnaire. Working level months (WLM) for each job prior to the date of entry at initial screening for both cases. Index of Arsenic Exposure Months (IAEM) which was calculated as a time weighted arsenic exposure (mg/m months) Skin Cumulated arsenic exposure (IAEM) st quartile nd quartile rd quartile th quartile % of lung cancer cases b Relative risk (9%. (.8.). (..9).9 (.9.) Age Not adjusted for radon. 7

8 Table.. Cohort studies of arsenic exposure and cancer Relative risk or SMR (9% Lubin et al. () Montana copper smelter, 98 8 white males employed months before 97 at a Montana copper smelter Employment records with information on work area, year started and year ended from the start of employment through September, 977 Airborne arsenic measured in light, medium and heavy areas with time weighted average airborne arsenic concentration Cancer Airborne arsenic exposure (years) Light and unknown Medium Relative risk (9%.9 (..). (.8.9).8 (..9).98 (..).9 (.9). (.7.). (..) Age calendar year Work status Duration of exposure Heavy 9.(.8.). (..8).8 (..) 8

9 Table.. Cohort studies of arsenic exposure and cancer Relative risk or SMR (9% Englyst et al. (), Sweden primary copper and lead smelter workers first employed for at least year during , and also included in a blood lead register started in 9. lost to follow up, were alive and were deceased at end of on December 987. From this original cohort, Lead Subcohort (7 workers of lead department and also employed at other works) and Lead Subcohort (8 workers of lead department never employed at As or Nickel plant or roaster or where exposure to carcinogen was known. Arsenic exposure via inhalation assessed based on detailed information in company occupational records and spot air sampling by company health service. At the end of 9s concentration of airborne arsenic was.. mg/m at roasters and lower at As department. Exposure to As among workers in As department was estimated close to Swedish occupational exposure limit of µg/m from 9 to 97 and µg/m from 97 to 987. Blood lead samples were obtained once or more each year. Malignant neoplasm ( 9); Gastrointestinal (); Respiratory (); ( ); Kidney (8); Renal pelvis, ureter, bladder (8); Brain, nervous system (9); Lymphoma, myeloma ( ); Leukemia ( 7) Lead sub cohort Malignant neoplasm Gastrointestinal Respiratory tract Kidney Renal pelvis, ureter, bladder Brain, nervous system Lymphoma, myeloma Leukemia Lead sub cohort Malignant neoplasm Gastrointestinal Respiratory tract Kidney Renal pelvis, ureter, bladder Brain, nervous system Lymphoma, myeloma Leukemia Findings not reported specifically for arsenic. All but one of lung cancer cases in sub cohorts had significant arsenic exposure. a Test of heterogeneity b Presented as % of lung cancer cases. SMR adj = Conventional SMRs adjusted to the lowest intensity/shortest duration exposure group SMR = No latency SMR = years minimum latency SMR = years minimum latency, exposure lagged years 9