Lead levels and related biochemical findings occurring in Ghanaian subjects occupationally exposed to lead

Abstract

Blood and urine lead levels in relation to blood delta-aminolevulinic acid dehydratase (ALAD) activity and also blood and renal status were evaluated in lead smelters, automobile mechanics and gasoline retailers in the city of Accra, Ghana. Relationship between high blood lead levels (mean: 108 ug/dl) and low ALAD activity (mean: 74.3 units) indicating lead over exposure was found in the lead smelters. Non-toxic lead exposure was, however, noted in the automobile mechanics and the gasoline retailers. Their respective mean blood lead levels were 27.8 ug/dl (mean blood ALAD activity 212.5 units) and 8.6 ug/dl (ALAD: 239.9 units). Personal habits at the work place appear to play a major role in facilitating exposure to lead among all the three groups of workers in addition to lack of control measures at the work place of the lead smelters to protect them against lead exposure. Anaemia was found in 48% of the lead smelters, 12.5% of the gasoline retailers but in none of the automobile mechanics. When compared with lead free subjects (mean blood ALAD activity: 270.9 units), urine microalbumin was significantly (p < 0.01) raised in all the lead smelters suggesting that they may be prone to renal glomerular damage. Plasma creatinine, BUN and uric acid were raised in only one of the lead smelters. The data supports the establishment of blood ALAD activity level at 100 units or less as indication of excessive body lead.