Triazine herbicide exposure and breast cancer incidence: an ecologic study of Kentucky counties.

Abstract

The incidence of breast cancer in the United States has steadily increased for the past three decades. Exposure to excess estrogen, in both natural and synthetic forms, has been implicated as a risk factor for the development of this disease. Considerable interest has been focused on organochlorines, such as the triazine herbicides, and their possible role in the initiation or promotion of human breast cancer. To explore this relationship, an ecologic study of Kentucky counties was designed. Exposure to triazines was estimated by use of water contamination data, corn crop production, and pesticide use data. A summary index of triazine herbicide exposure was developed to classify counties into low, medium, or high exposure levels. Data on county breast cancer rates were obtained from the state registry. A Poisson regression analysis was performed, controlling for age, race, age at first live birth, income, and level of education. Results revealed a statistically significant increase in breast cancer risk with medium and high levels of triazine exposure [odds ratio (OR) = 1.14,p<0.0001 and OR = 1.2, p<0.0001, respectively]. The results suggest a relationship between exposure to triazine herbicides and increased breast cancer risk, but conclusions concerning causality cannot be drawn, due to the limitations inherent in ecologic study design.ImagesFigure 1.Figure 2.

From silent spring to silent night: Agrochemicals and the anthropocene

“…Atrazine exposure during gestation can even result in prostate disease in neonatal rodents (Stanko et al, 2010). Atrazine is also associated with breast cancer (Kettles et al, 1997) and is correlated with an 8.4 fold increase in prostate cancer incidence in men working in an atrazine production facility (Maclennan et al, 2002).…”

“…Atrazine exposure during gestation can even result in prostate disease in neonatal rodents (Stanko et al, 2010). Atrazine is also associated with breast cancer (Kettles et al, 1997) and is correlated with an 8.4 fold increase in prostate cancer incidence in men working in an atrazine production facility (Maclennan et al, 2002).Atrazine also produces reproductive abnormalities in vertebrates under controlled laboratory conditions. For example, atrazine causes partial or complete sex reversal in fish (Tillitt et al, 2008, Suzawa andIngraham, 2008), amphibians (Hayes et al, 2002a, Hayes et al, 2006b, Hayes et al, 2010b, Hayes et al, 2002b, Hayes et al, 2002c, and reptiles (De Solla et al, 2006).…”

Epidemiological data on the relationship between cancer and pesticides

“…Des questions spé cifiques se posent pour les cancers du sein, de l'ovaire, de l'uté rus, argumenté es par les perturbations endocriniennes attribué es à certains pesticides. Mê me si le rô le des organochloré s dans la survenue de cancer du sein a é té largement recherché et si certaines é tudes ont suggé ré un lien entre les triazines, et la survenue de cancer de l'ovaire [18,27], les é lé ments provenant des é tudes é pidé miologiques actuellement publié es sur ces sites de cancer sont assez peu convaincants. Les ré cents ré sultats de l'AHS montrent que chez les applicatrices de certains organophosphoré s ainsi que chez les é pouses d'agriculteurs, le risque de cancer du sein est augmenté [20].…”

Pesticide Impact Assessment via Using Enzyme-linked Immunosorbent Assay (ELISA) Technique in the Lower Rio Grande River Basin, Texas

“…Hayes et al (2002) found that, at a level as low as 0.1 ppb, atrazine causes sexual deformities in frogs. Kettles et al (1997) found a statistically significant relationship between the exposure to triazine herbicides and increased breast cancer risk in Kentucky using data on county-wide breast cancer rates. Breast cancer is the most common form of cancer among adult women in the United States (USA) Ries et al 1998) and known risk factors are thought to explain only about half of the cases occurring nationwide (Madigan et al 1995).…”