Dioxins, environmental pollutants resulting from the production and combustion of chlorinated compounds, are likely to increase ischemic heart disease (IHD) and cardiovascular disease (CVD) mortality rates, according to a new study.
The research has been reported in a review article in the November 2008 issue of the peer-reviewed journal Environmental Health Perspectives (EHP).
A December 2007 PubMed search of English-language epidemiologic studies and their citations regarding dioxin exposure and CVD mortality provided the basis for the systemic review.
The authors, researchers at the Harvard School of Public Health and the U.S. Environmental Protection Agency, selected studies on original mortality data from all cases of CVD or IHD.
They excluded studies of leather, flavor, and fragrance workers, whose occupational exposures typically include not only dioxin but also cardiotoxic methylmercury, arsenic and xylene. Finally, they grouped the studies by their quality, according to two well-recognized criteria.
The studies considered to be of the highest quality found consistent and significant dose-related associations with IHD mortality and more modest associations with all-CVD mortality.
Although a number of epidemiologic studies have examined the association of dioxin exposure with CVD morbidity or mortality, the authors found no published systematic reviews on this topic.
This is possibly because dioxin epidemiology research has focused primarily on the association with various cancers.
The authors wrote that future studies in both animals and humans should assess whether cardiovascular effects are present at environmentally relevant doses of dioxin.
EHP editor-in-chief Hugh A. Tilson, PhD, said, "With cardiovascular disease a leading cause of death in many countries, the potential role of dioxin exposure as a preventable risk factor could be of substantial interest."