Polycyclic Aromatic Hydrocarbons and Digestive Tract Cancers: A Perspective

Abstract

Cancers of the colon are most common in the Western world. In majority of these cases, there is no familial history and sporadic gene damage seems to play an important role in the development of tumors in the colon. Studies have shown that environmental factors, especially diet, play an important role in susceptibility to GI tract cancers. Consequently, environmental chemicals that contaminate food or diet during its preparation becomes important in the development of GI cancers. Polycyclic aromatic hydrocarbons (PAHs) are one such family of ubiquitous environmental toxicants. These pollutants enter the human body through consumption of contaminated food, drinking water, inhalation of cigarette smoke, automobile exhausts, and contaminated air from occupational settings. Among these pathways, dietary intake of PAHs constitutes a major source of exposure in humans. Although many reviews and books on PAHs and their ability to cause toxicity and breast or lung cancer have been published, aspects on contribution of diet, smoking and other factors towards development of digestive tract cancers and strategies to assess risk from exposure to PAHs have received much less attention. This review, therefore, focuses on dietary intake of PAHs in humans, animal models, and cell cultures used for GI cancer studies along with epidemiological findings. Bioavailability and biotransformation processes, which influence the disposition of PAHs in body and the underlying causative mechanisms of GI cancers, are also discussed. The existing data gaps and scope for future studies is also emphasized. This information is expected to stimulate research on mechanisms of sporadic GI cancers caused by exposure to environmental carcinogens.

Adherence to WCRF/AICR lifestyle recommendations for cancer prevention and the risk of Barrett’s esophagus onset and evolution to esophageal adenocarcinoma: results from a pilot study in a high-risk population

“…Moreover, the consumption of red and processed meat has been found to be associated with other epithelial-deriving neoplasms, and this evidence is supported by the results of the aforementioned study by Romaguera et al [16]. There are also mechanistic data that support this hypothesis: Red meats feature many compounds that are known to induce DNA mutation such as heme iron, heterocyclic amines and polycyclic aromatic hydrocarbons [34][35][36]. A direct correlation between refined cereals has been found to be associated with an increased risk of BE, EAC and cancer in general [37,38].…”

Antimutagenic and antioxidant activity of a protein fraction from aerial parts ofUrtica dioica

“…The antimutagenicity was highlighted against 2AA, which represents one of the main carcinogenic health hazards associated to occupational exposure and dietary intake, being frequently formed at high temperatures during cooking and frying of meat and fish, or during the incomplete combustion of organic compounds (Diggs et al, 2011). Figure 1.…”

Polycyclic-Aromatic Hydrocarbon (Pahs) in Environment and Human Health: A Review.

“…Even at low levels long term exposure to some PAHs viz., pyrene and BaP has been identified as the cause of cancer in laboratory animals (Diggs et al, 2011). Toxic kinetics study on animal has also shown adverse reproductive and developmental effects from PAHs exposure as such effects have not usually been detected in humans (Wells et al, 2010).…”