Investigating tea temperature and content as risk factors for esophageal cancer in an endemic region of Western Kenya: Validation of a questionnaire and analysis of polycyclic aromatic hydrocarbon content

• Published in: Cancer epidemiology Vol. 60; pp. 60 - 66
• Main Authors: Mwachiro, Michael M., Parker, Robert K., Pritchett, Natalie R., Lando, Justus O., Ranketi, Sinkeet, Murphy, Gwen, Chepkwony, Robert, Burgert, Stephen L., Abnet, Christian C., Topazian, Mark D., Dawsey, Sanford M., White, Russell E.
• Format: Journal Article
• Language: English
• Published: Netherlands Elsevier Ltd 01-06-2019; Elsevier Limited
• Subjects: Adolescent; Adult; Aged; Aromatic hydrocarbons; Beverages; Black tea; Cancer; Epidemiology; Esophageal cancer; Esophageal neoplasms; Esophageal Neoplasms - epidemiology; Esophageal Neoplasms - etiology; Esophageal Squamous Cell Carcinoma - epidemiology; Esophageal Squamous Cell Carcinoma - etiology; Esophagus; Female; Health risk assessment; Health risks; Hot Temperature; Humans; Kenya; Kenya - epidemiology; Male; Medical prognosis; Middle Aged; Polycyclic aromatic hydrocarbons; Polycyclic Aromatic Hydrocarbons - analysis; Questionnaires; Risk analysis; Risk Factors; Squamous cell carcinoma; Studies; Surveys and Questionnaires; Tea; Tea - chemistry; Young Adult; Kenya; Tea; Hot temperature; Polycyclic aromatic hydrocarbons; PAH; NIST; Esophageal neoplasms; IARC; Kenya; ESCC
• ISSN: 1877-7821; 1877-783X
• DOI: 10.1016/j.canep.2019.03.010

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•Participants who live in western Kenya, a region endemic for esophageal cancer, consume substantial amounts of chai.•Participants prefer to drink chai at an initial average temperature of 72.1°C, higher than any other reported area.•The questionnaire responses, relevant to the region, predict the temperature of chai consumption, with moderate agreement.•Polycyclic aromatic hydrocarbons are not present at remarkable levels in tea leaves throughout Kenya.
Esophageal squamous cell carcinoma (ESCC) is common in certain areas worldwide. One area, western Kenya, has a high risk of ESCC, including many young cases (<30 years old), but has limited prior study of potential risk factors. Thermal injury from hot food and beverages and exposure to polycyclic aromatic hydrocarbons (PAHs) have been proposed as important risk factors for ESCC in other settings. The beverage of choice in western Kenya is milky tea (chai).
Healthy individuals >18 years of age who were accompanying relatives to an endoscopy unit were recruited to participate. The preferred initial temperature of chai consumption in these adults was measured by questionnaire and digital thermometer. Comparisons of these results were assessed by kappa statistics. Concentrations of 26 selected PAHs were determined by gas chromatography/mass spectrometry in samples of 11 brands of commercial tea leaves commonly consumed in Kenya.
Kappa values demonstrated moderate agreement between questionnaire responses and measured temperatures. The mean preferred chai temperatures were 72.1 °C overall, 72.6 °C in men (n = 78), and 70.2 °C in women (n = 22; p < 0.05). Chai temperature did not significantly differ by age or ethnic group. The PAH levels in the commercial Kenyan tea leaves were uniformly low (total PAH < 300 ng/g of leaves).
Study participants drink chai at higher temperatures than previously reported in other high-risk ESCC regions. Chai is not, however, a source of significant PAH exposure. Very hot chai consumption should be further evaluated as a risk factor for ESCC in Kenya with the proposed questionnaire.