We interviewed 282 histologically confirmed cases of nasopharyngeal carcinoma (NPC) in Chinese residents of Selangor and the Federal Territory, Malaysia, and an equal number of Chinese age‐, sex‐, and length‐of‐residence‐matched controls sampled from the general population. Consumption of 55 dietary items during childhood, and 5 years pre‐diagnosis of NPC, was analyzed by univariate and multivariate methods. Four salted preserved foods (fish, leafy vegetables, egg and root), fresh pork/beef organ meats and beer and liquor consumption exhibited strong positive associations, and 4 vegetable/fruit combinations strong negative associations with NPC. Factor analysis and multivariable modeling using estimated factor scores strongly supported separate effects on NPC of vegetables/fruits, salted preserved foods, pork/beef organ meats and beer/liquor consumption. Multivariable modeling associated NPC most clearly with high consumption of salted fish, salted eggs, pork/beef liver and beer and low consumption of Chinese flowering cabbage, oranges/tangerines and shrimp. A strong residual association of social class with NPC remained after adjustment for diet, which is consistent with a substantial role for non‐dietary environmental factors. Int. J. Cancer 77:228–235, 1998.© 1998 Wiley‐Liss, Inc.

This study supports previous findings that some occupational inhalants are risk factors for NPC. The statistical effect of wood dust remained substantial after adjustment for diet, cigarette smoke, and social class. Intense industrial heat emerged as a previously unreported risk factor, statistically significant even after adjustment for diet and cigarette smoke. No association was found between NPC and formaldehyde.

Objectives-To examine the effect of occupation on respiratory symptoms in a randomly selected adult population aged 20-44 years.Methods-It is based on the phase II sampling of the New Zealand part of the European Community respiratory health survey. 1609 people (63.9% response rate) completed a detailed respiratory questionnaire. Of those responding, 1174 (73%) underwent skin tests and 1126 (70%) attended to undergo methacholine bronchial challenge. Current occupation was recorded and a previous occupation was also recorded if it had led to respiratory problems. 21 occupational groups were used for analysis for the five definitions of asthma: wheezing in the previous 12 months; symptoms related to asthma; bronchial hyperresponsiveness (BHR); BHR with wheezing in the previous 12 months; and BHR with symptoms related to asthma. Results-Prevalence odds ratios (ORs) were significantly increased for farmers and farm workers (OR 4-16, 95% confidence interval (95% CI) 1-33 to 13-1 for the combination of wheezing and BHR). Increased risks of prevalence of asthma were also found for laboratory technicians, food processors (other than bakers), chemical workers, and plastic and rubber workers. Workers had also been divided into high and low risk exposure categories according to relevant publications. The prevalence of wheezing was greater in the high risk group (OR 1-57, 95% CI 0-83 to 2.95) than in the low risk group. Atopy was associated with asthma, but the prevalence of atopy did not differ significantly between occupational exposure groups. The attributable risk of wheezing that occurred after the age of 15 years and that was estimated to be due to occupational exposure (based on the defined high risk group) was 1-9%, but this increased to 3-1% when farmers and food processors (other than bakers) were also included in the high risk group. Conclusions-This population based study has identified certain occupations significantly associated with combinations of asthmatic symptoms and BHR.

The objectives of this study were to measure the population prevalence of symptoms of chronic obstructive lung disease and mild airway obstruction and to compare these between occupational groups. There were 1,609 subjects (63.9% response rate) who completed a respiratory questionnaire. Of these, 1,132 (70.4%) underwent pulmonary function testing (FEV1 and FVC). Twenty-one categories of current occupation were used for analysis. Four definitions of chronic obstructive pulmonary disease (COPD) were used: (1) chronic bronchitis, (2) chronic bronchitis with airway obstruction, (3) shortness of breath, and (4) shortness of breath with airway obstruction. For chronic bronchitis, adjusted prevalence odds ratios were significantly elevated for food processors other than bakers (OR = 2.83; 95% CI, 1.27 to 6.29) and chemical processors (OR = 18.84; 3.71 to 95.64). The combination of chronic bronchitis and mild airway obstruction (FEV1/FVC < 0.75) was associated with bakers (OR = 25.5; 3.86 to 168.53) and spray painters (OR = 14.40; 2.85-72.69). Shortness of breath was associated with hairdressers (OR = 2.75; 0.80 to 9.42) and bakers (OR = 6.72; 0.57 to 79.66), and nursing was associated with lower levels of shortness of breath (OR = 0.42; 0.16 to 1.15). Working ever with vapors, gases, dust, or fumes was significantly associated with chronic bronchitis and airway obstruction (OR = 3.13; 1.07 to 9.12). This population-based study has identified certain occupations with increased prevalence of chronic bronchitis and COPD.

The incidence patterns of adenocarcinomas of the oesophagus and gastric cardia in New Zealand should be monitored over the next decade for confirmation of the trends observed here. There is need to review the quality of the data in the New Zealand registry.