RADIOIMMUNE ASSAY OF URINARY COTININE

Urinary cotinine was assessed by a radioimmune assay (RIA) in a random subsample of 63 (out of 285) children aged 5 to 6 from 10 kindergarte ns in Nancy (N-E France). The result was adjusted for urine concentrat ion by expressing cotinine per mg creatinin. The correlation between t wo successive determinations was excellent (r = 0.989) and the differe nce between the two mean values was minimal and non-significant (121.4 +/- 25.9 vs 121.0 +/- 25.0). Expressed in percentage of their mean, t he difference between two determinations was on average 8.2%. The urin ary cotinine determinations allowed a satisfactory separation of child ren exposed vs unexposed to parental tobacco smoke.