[Environmental exposure to inorganic lead and neurobehavioural tests among adolescents living in the Sulcis-Iglesiente, Sardinia]. / Esposizione ambientale a piombo e test neuro- comportamentali in adolescenti del Sulcis-Iglesiente.

In several recent studies blood lead levels below 100 microg/L have been associated with reduced neurocognitive capacities and neurobehavioural performances in children, with no clear evidence of the lowest "safe" level not associated to adverse effects on the CNS. We analyzed blood lead concentration and the results of 5 neurocognitive tests, two derived from the Swedish Performance Evaluating System (SPES) and three from the Wechsler Intelligence Scale for Children-Revised (WISC-R), in 139 Sardinian adolescents living in Portoscuso, a town 2 Km far from a lead smelter, and in 72 age-matched students living in S. Antioco, a town about 15 Km far from the same smelter. The blood lead concentrations were lower than 100 microg/l in almost subjects, but, in average, significantly higher particularly among males, in the Portoscuso group compared to controls. The regression coefficients derived from the multivariate stepwise analysis, adjusted for the student's age and gender and for the educational and socio-economic level of parents, showed that reduced performances in neurocognitive test were significantly associated to increasing blood lead concentrations. According to previous our surveys in the same area and to the recent scientific literature on this topic, the present study suggests the need to further low the blood lead levels, considered by the U.S. CDC in 1991 as potentially "safe" for the children's CNS, to a threshold possibly < 50 microg/L.

[Respiratory risk among students in an industrialized area of Sardinia: role of smoking and air pollution]. / Rischio respiratorio in studenti di un'area industrializzata della Sardegna: fumo di tabacco e inquinamento ambientale.

Among 273 students (age 11-16 years) living in two small towns located respectively 2 (Portoscuso) and 15 kilometres (S. Antioco) far from the industrial area of Portovesme, the respiratory risk associated to cigarette smoking and environmental pollution was evaluated by the ISAAC questionnaire and standardized spirometry. The prevalence of parent's smoking was high in both groups (66.3% and 59.4%). Smoking during pregnancy was reported by 15% of mothers, without significant differences between the two schools. The prevalence of smokers among students was similar comparing the two groups (7% vs 6%). The prevalence of asthma in the whole population was significantly associated to skin positivity to common allergens, to the familiarity for asthma and to the environmental tobacco smoking, particularly if maternal. Spirometric values were significantly lower among students living in Portoscuso than among those of the S. Antioco school, with an evident interaction between the residential factor and the tobacco smoking, active and/or passive, in reducing the forced end- expiratory flows. Our results support the significant role of tobacco smoking, active and passive, particularly if derived from maternal smoking during pregnancy, in increasing the prevalence of respiratory disorders and lowering lung function in children. Living in Portoscuso, because of higher environmental exposure to airborne pollutants of industrial origin, has been shown as a relevant factor further lowering the lung function among the studied sample.

[Intellectual quotient and environmental exposure to low doses of lead]. / Quoziente intellettivo ed esposizione ambientale a basse dosi di piombo.

The effects of low-level lead exposure on children's intelligence quotient (IQ) were investigated in 64 Sardinian adolescents (13-16 years old). To estimate potential early adverse effects on the Central Nervous System (CNS) due to very low-level lead, the Intelligence Quotient (IQ) of adolescents with present blood lead concentrations (PbB) generally below 10 microg/dl was measured. We analyzed blood lead concentration and individual IQ of 32 Sardinian children living in Portoscuso, a town 2 Km far from a lead smelter, and of other 32 controls living in S. Antioco, a town about 15 Km far from the same smelter. The Wechsler Intelligence Scale for Children Revised (WISC-R) was administered. The relation between IQ and blood lead concentration was estimated by linear multivariate models adjusting for several potential confounders, such as the educational and socio-economic level of the parents. The blood lead concentration was in average significantly higher in the Portoscuso group compared to controls. The linear model applied to the total population studied (n 64) showed that the blood lead concentration was inversely and significantly associated with IQ, with an extrapolated decline of 1.29 points in total IQ for each microg/dl increase of lead blood concentration. According to the recent scientific literature on this topic, results of our pilot study suggest the need to further lower the blood lead concentration for children to a threshold significantly below 10 microg/dl, value till now considered "safe" for the children's CNS.

[Cognitive and performance capacity among adolescents living near a lead and zinc smelter]. / Capacità cognitive e di performance in adolescenti residenti in prossimità di una fonderia di piombo e zinco.

To estimate potential early adverse effects on the Central Nervous System (CNS) due to very low exposure to inorganic lead, the Intelligence Quotient (IQ) of adolescents with present blood lead concentrations (PhB) generally below 10 micrograms/dl was measured. We analyzed blood lead concentration and individual IQ of 32 Sardinian adolescents living in Portoscuso, a town 2 Km far from a lead smelter, and of other 32 controls living in S. Antioco, a town about 15 Km far from the same smelter. The Wechsler Intelligence Scale for Children Revised (WISC-R) was administered. The relation between IQ and blood lead concentration was estimated by linear multivariate models adjusting for several potential confounders, such as the educational and socio-economic level of the parents. The blood lead concentration was in average significantly higher in the Portoscuso group compared to controls. The linear model applied to the total population studied (n 64) showed that the blood lead concentration was inversely and significantly associated with IQ, with an extrapolated decline of 1.29 points in total IQ for each microgram/dl increase of blood concentration. According to the recent scientific literature on this topic, results of our pilot study suggest the need to further lower the definition of an elevated blood lead concentration for children to a threshold significantly below 10 micrograms/dl, value till now considered "safe" for the children's CNS.