Lead concentration was determined in the hair of 327 school children living in a wastewater spreading field of Marrakesh (Morocco). The influence of age, sex, food habit and family occupation on the children's hair Pb concentration was also evaluated. Girls had more metal in their hair than boys (respectively 16.5 ٌ 5.4 mu g/g and 12.5 ٌ 3.5 mu g/g), and lead levels decreased with age. Family occupation, direct contact with wastewater, customs and food habits were the most significant factors influencing the metal's content of children's hair. The average Pb content was higher in the exposed children (14.8 ٌ 4.5 mu g/g) than in the non-exposed children (4.6 ٌ 2.2 mu g/g), and such difference was statistically significant.