title: Survey of polycyclic aromatic hydrocarbons and lead in Chinese teas sold in Nigeria: levels and health implications.
abstract: BACKGROUND
  The belief that Chinese teas are of immense health benefits by many Nigerians has led to high consumption rate.
  
  
  OBJECTIVE
  This study has determined lead and polycyclic aromatic hydrocarbons (PAHs) levels of Chinese teas popularly consumed in Nigeria and to estimate the potential health risks.
  
  
  METHODS
  Twenty brands of Chinese teas commonly consumed in Nigeria purchased in October 2014 were used in the study. Tea samples were extracted and digested. Lead, and PAHs were analyzed using an atomic absorption spectrophotometric (AAS) and gas chromatographic methods, respectively. Daily intake, percent violations of permissible limits, target hazard quotients (THQ), Health Risk Index (HRI) of lead, and other cancer risk parameters of PAHs were estimated.
  
  
  RESULTS
  All the tea samples except super natural green tea violated the WHO permissible limit of lead (0.01 mg/kg) by over 100%. The HRI ranged from 5.09×10(-5)-7.20×10(-4). Among the single analyzed compounds, the pyrenes had the highest concentration of 14.31 mg/kg. The intake of benzo[a]pyrene was detected in 25% of the samples which ranged from 0.066 to 0.145 mg/kg and exceeded the permissible daily limit of benzo[a]pyrene intake. The estimated cancer risk from this study in an adult is 5.07×10(-9).
  
  
  CONCLUSIONS
  The present study suggests that consumption of Chinese teas in Nigeria may not be one of the factors responsible for the increased rate of cancer in Nigeria.
authors.affiliation: Toxicology Unit, Clinical Pharmacy, Faculty of Pharmacy, University of Port-Harcourt, Rivers State, Nigeria.
authors.forename: Orish Ebere
authors.initials: OE
authors.lastname: Orisakwe
authors.affiliation: Department of Pharmacology, Faculty of Pharmacy, University of Uyo, Akwa Ibom State, Nigeria.
authors.forename: Herbert Orji Chidi
authors.initials: HO
authors.lastname: Mbagwu
authors.affiliation: Department of Pharmacology, Faculty of Pharmacy, University of Uyo, Akwa Ibom State, Nigeria.
authors.forename: Peter
authors.initials: P
authors.lastname: Ukpai
authors.affiliation: Toxicology Unit, Clinical Pharmacy, Faculty of Pharmacy, University of Port-Harcourt, Rivers State, Nigeria.
authors.forename: Nnaemeka Arinze
authors.initials: NA
authors.lastname: Udowelle
mesh_terms: D001564:Benzo(a)pyrene / Q000032:analysis*; D002273:Carcinogens / Q000032:analysis; D002681:China; D004785:Environmental Pollutants / Q000633:toxicity; D005506:Food Contamination / Q000032:analysis*; D008401:Gas Chromatography-Mass Spectrometry; D006801:Humans; D009549:Nigeria; D011084:Polycyclic Aromatic Hydrocarbons / Q000032:analysis*; D013662:Tea / Q000737:chemistry*
chemical_list: D002273:Carcinogens; D004785:Environmental Pollutants; D011084:Polycyclic Aromatic Hydrocarbons; D013662:Tea; D001564:Benzo(a)pyrene