Time trends in cancer risk and pesticide exposure, a long-term follow-up of Danish gardeners
本研究追踪了3156名丹麦男性园丁的癌症发病率，发现1915年前出生者患白血病和软组织肉瘤风险显著升高，而之后出生者风险未增加，提示农药暴露监管措施有效。
OBJECTIVES: Occupational exposure to petrochemical pesticides was high during the first 10-15 years after their introduction in the late 1940s, and, during these years, many cases of intoxication occurred. In the 1960s, the use and marketing of pesticides was regulated to reduce exposure to these substances, and, since 1970, substantial exposure has been rare in Denmark. The present study aimed at investigating the extent to which these alterations have influenced the cancer risk of gardeners. METHODS: A historical cohort of 3156 male gardeners was followed from May 1975 until 2002 with regard to cancer incidence. RESULTS: The cancer incidence was significantly below the national average [standardized incidence ratio (SIR) 0.86, 95% confidence interval (95% CI) 0.79-0.94], but an analysis by birth cohort indicated marked differences with a downward tendency for younger birth cohorts. Among the gardeners born prior to 1915, significant increases were found for leukemia (12 cases, SIR 2.33, 95% CI 1.32-4.10) and soft tissue sarcoma (3 cases, SIR 5.87, 95% CI 1.89-18.20). CONCLUSIONS: Gardeners constitute a healthy worker group, but an increased risk of soft tissue sarcoma and leukemia is indicated for people born prior to 1915, a finding that may reflect substantial pesticide exposure during the late 1940s and the 1950s. Among the gardeners born in 1915 or later, no excess cancer risk was found. The latter finding suggests a cancer-preventive effect for safety recommendations and improved technical devices with respect to pesticide application, along with legislative control measures to reduce pesticide exposure.