Document Type


Date of Award

Spring 5-18-2014


College of Science, Engineering, and Technology (COSET)

Degree Name

MS in Environmental Toxicology

First Advisor

Professor Mahmoud Saleh


Polycyclic aromatic hydrocarbons (PAHs) belong to an extensive group of hydrocarbons which have been characterized as Chemical compounds of potential concern (COPCs); as a result of their mutagenic and carcinogenic potential in humans. This study involved the evaluation ofthe concentration of 18-priority PAHs (as described by US.EPA and IARC) present in different tea brands and an assessment of the carcinogenic risk due to the consumption ofthe various brands oftea; from Green, Grey, Black, fine, to decaffeinated brands. All tea brands were found to contain between 10-17 PAHs. Benzo(a)pyrene, Benzo(a)anthracene, Benzo(a)fluoranthene, Benzo(k) fluoranthene, Indeno(I,2,3-c-d)pyrene, Chrysene and Dibenz(a,h)anthracene were found in all the tea samples. These listed possible/probable carcinogenic PAHs formed the basis ofthe estimation ofthe toxic equivalent (TEQ) based on their similar mechanism oftoxic 1 2 action and the assumption that their combined toxic effect is additive. Black tea was found to have the highest TEQ (110.9) while a decaffeinated grey tea (9.35) followed by a decaffeinated green tea (9.64) were found to have the lowest TEQ; amongst a total of 28-samples. Decaffeinated tea brands are therefore recommended to be consumed by tea lovers; until highly dependable regulatory standards controlling the amount of pro carcinogenic PAHs in tea are instituted.