title: Distribution of arsenic, cadmium, lead, and nickel levels in biological samples of Pakistani hypertensive patients and control subjects.
abstract: BACKGROUND
  The abnormal metabolism of metal ions plays an important role in health and disease conditions, and studies about them have been attracting significant interest. The aim of our study was to assess the toxic elements arsenic (As), cadmium (Cd), nickel (Ni), and lead (Pb) in biological samples (scalp hair, blood, urine) of 387 hypertensive males and females, aged between 30 and 60 years, from an urban population together with 439 non-hypertensive subjects, of the same age group and residential areas.
  
  
  METHODS
  The element concentrations were measured by means of an electrothermal atomic absorption spectrophotometer after microwave-induced acid digestion. The validity and accuracy was checked by conventional wet acid digestion method and using certified reference materials. The overall recoveries of all elements were found in the range of 96.8 - 99.4% of certified values.
  
  
  RESULTS
  The results indicated significantly higher levels of As, Cd, Ni, and Pb in the biological samples (scalp hair, blood and urine) of hypertensive patients, when related to controls of both genders.
  
  
  CONCLUSIONS
  The high exposure of toxic elements may be synergistic with risk factors associated with hypertension. These data present guidance to clinicians and other professionals who will be investigating the toxicity of heavy elements in biological samples (scalp hair and blood) of hypertensive patients.
authors.forename: Hassan Imran
authors.initials: HI
authors.lastname: Afridi
authors.forename: Tasneem Gul
authors.initials: TG
authors.lastname: Kazi
authors.forename: Farah Naz
authors.initials: FN
authors.lastname: Talpur
authors.forename: Salma
authors.initials: S
authors.lastname: Arain
authors.forename: Sadaf Sadia
authors.initials: SS
authors.lastname: Arain
authors.forename: Naveed
authors.initials: N
authors.lastname: Kazi
authors.forename: Abdul Haleem
authors.initials: AH
authors.lastname: Panhwar
mesh_terms: D000328:Adult; D001151:Arsenic / Q000032:analysis*; D002104:Cadmium / Q000032:analysis*; D016022:Case-Control Studies; D005260:Female; D006197:Hair / Q000737:chemistry*; D006801:Humans; D006973:Hypertension / Q000097:blood* / Q000652:urine*; D007854:Lead / Q000032:analysis*; D008297:Male; D008872:Microwaves; D008875:Middle Aged; D009532:Nickel / Q000032:analysis*; D010154:Pakistan; D015203:Reproducibility of Results; D012307:Risk Factors; D013054:Spectrophotometry, Atomic; D014505:Urban Population
chemical_list: D002104:Cadmium; D007854:Lead; D009532:Nickel; D001151:Arsenic