John Libbey Eurotext

Environnement, Risques & Santé


Evaluation of the lead burden of a rural population that uses wastewater for agricultural purposes in the region of Settat, Morocco Volume 9, issue 5, Septembre-Octobre 2010

Cabinet de médecine interne 11 Bd Skirej Settat BP 1325  Maroc, Centre Antipoison et de pharmacovigilance Rue Lamfedel Cherkaoui Rabat Instituts Madinate Al Irfane BP 6671 Rabat 10100Maroc, Cabinet de neurologie Résidence Laaroussi N°1 Avenue Mohammed V Appartement 1Settat Maroc, Laboratoire d'analyses biomédicales 97, Bd Mohammed VSettat Maroc, Université Hassan 1erFaculté des sciences humaines Unité de statistique Complexe universitaire Route de Casablanca Settat 26000Maroc, CHU Laboratoire de pharmacologie et de toxicologie 4, rue Larrey 49933 Angers France
  • Key words: blood, lead, Morocco, risk, sewage, urine
  • DOI : 10.1684/ers.2010.0380
  • Page(s) : 419-27
  • Published in: 2010

Objectives: This investigation was undertaken to assess the lead burden of a rural population that uses wastewater for agriculture in the province of Settat. Methods: The study covered 215 subjects, 116 living in two rural douars (mean age: 29.2 ± 20.2 years) that used wastewater for agriculture and 99 in another douar that does not use its wastewater (mean age: 31.4 ± 19.1 years). Each person who agreed to participate received a complete clinical examination that included the collection of historical information, especially past diseases, occupation, and exposure to wastewater. Blood and urine samples were taken, and blood and urinary lead levels assessed by ICP-MS (inductively coupled plasma mass spectometry). Results: The mean blood lead level in the exposed population was 50.4 ± 27.5 μg/L and in the unexposed population, 48.0 ± 21.8 μg/L. This difference was not significant (p = 0.44). Values were significantly higher among boys and men (p = 0.0001). They were also higher at the lowest and highest ages. They were not significantly influenced by smoking or drinking alcoholic beverages. The prevalence of an elevated blood lead level (100 μg/L) was significantly higher (p = 0.017) in exposed population, that is, 7.8% compared with only 1.0% in the unexposed population. These elevated blood lead levels were not accompanied by anemia, kidney disease or neurological disorders. On the other hand, bone risk was significantly more frequent. The urinary lead value for the exposed population was 4.7 ± 5.2 μg/L and for the unexposed population, 5.3 ± 3.4 μg/L. The difference was not significant (p = 0.38). Conclusion: The prevalence of elevated blood lead levels was significantly higher in the population using wastewater in agriculture, compared with the unexposed population (p = 0.017). The lead burden observed in the rural environment of Settat was close to or even lower than that in other countries. Preventive measures are essential, as well as monitoring, medical education, the use of lead-free kohl, and especially adequate treatment of the wastewater before its discharge into the environment, especially if agricultural re-use is considered.