Cancer incidence among Finnish farmers, 1995–2005

Abstract

Objectives The aim of this study was to describe the cancer risk pattern of male and female Finnish farmers and to define the role of the type of farm production as a risk determinant.Methods All farmers on 31 December 1978 living on 1 January 1995 were included in the cohort. The data concerning continuation as a farmer and the type of farming was collected from the 31 December 1990 and 1994 farm registries. The observed number of cases in each stratum was divided by the respective expected number based on national incidence rates to calculate the standardized incidence ratio. ResultsThe overall cancer incidence was smaller than that of the general population. For most of the cancer sites, the standardized incidence ratios were below 1.0. The lowest rates for farmers continuing to farm were determined for mesothelioma and cancers of the liver, larynx, lung, nose, esophagus, and urinary bladder. The only significantly elevated standardized incidence ratio was that for lip cancer. Permanent beef and dairy farmers had the lowest standardized incidence ratios for overall cancer. Dairy farmers of 1978 who had changed their production type to crop farmers had increased their risk for overall cancer from a standardized incidence ratio of 0.82 to 0.92. ConclusionsThe cancer incidence of Finnish farmers was significantly below the national average. The finding that lung cancer risk was low among dairy farmers but increased with a change to another type of farm production gives some support to the hypothesis that endotoxin exposure may decrease cancer risk.

Cancer risks in a population-based study of 70,570 agricultural workers: results from the Canadian census health and Environment cohort (CanCHEC)

“…As a result, individuals employed in agriculture tend to experience lower overall morbidity and mortality compared to the general population, and also exhibit distinctive cancer risk profiles [1–4]. Studies of cancer incidence and mortality in farmers have consistently reported reduced risks of tobacco-related cancers, such as lung and bladder [2, 3, 5–7]. Lower incidence of colorectal cancer has also been attributed to this favourable risk factor profile that includes higher levels of physical activity [3, 5, 7–9].…”

The biography of the immune system and the control of cancer: from St Peregrine to contemporary vaccination strategies

“…The degree of apparent protection is related to the intensity of the exposure (the number of cattle to which the farmers were exposed) but wanes when the farmers change to other occupations. These findings were confirmed in a high-quality study in Finland [49], and in a meta-analysis of published reports [50]. Although it has been claimed that the agents conferring protection are endotoxins that are present in the dust derived from cattle faeces [51], it is equally likely that apparent protection is mediated by various genera and species of actinomycetes, which are likewise present, and at high densities, in cowsheds.…”

Microbial deprivation, inflammation and cancer

“…A recent study of the Finnish farmers including all farmers in the national farm register revealed that the overall standardised incidence ratio among farmers was significantly reduced, and for most cancers, the incidence was below 1.0 [25]. Concordant results were recently obtained for Italian farmers [26].…”

“…Accumulating data obtained from several lines of evidence suggest that cancers occur less frequently 1. Among people who are, by occupation, heavily exposed to environmental micro-organisms [25][26][27][28][29][30][31][32][33] 2. Among populations that adhere to a traditional lifestyle [34] 3.…”