Neurocognitive impact of metal exposure and social stressors among schoolchildren in Taranto, Italy

BACKGROUND: Metal exposure is a public health hazard due to neurocognitive effects starting in early life. Poor socio-economic status, adverse home and family environment can enhance the neurodevelopmental toxicity due to chemical exposure. Disadvantaged socio-economic conditions are generally higher in environmentally impacted areas although the combined effect of these two factors has not been sufficiently studied. METHODS: The effect of co-exposure to neurotoxic metals including arsenic, cadmium, manganese, mercury, lead, selenium, and to socio-economic stressors was assessed in a group of 299 children aged 6-12\u2009years, residing at incremental distance from industrial emissions in Taranto, Italy. Exposure was assessed with biological monitoring and the distance between the home address and the exposure point source. Children's cognitive functions were examined using the Wechsler Intelligence Scale for Children (WISC) and the Cambridge Neuropsychological Test Automated Battery (CANTAB). Linear mixed models were chosen to assess the association between metal exposure, socio-economic status and neurocognitive outcomes. RESULTS: Urinary arsenic, cadmium and hair manganese resulted inversely related to the distance from the industrial emission source (\u3b2 -\u20090.04; 95% CI -0.06, -\u20090.01; \u3b2 -\u20090.02; 95% CI -0.05, -\u20090.001; \u3b2 -\u20090.02 95% CI -0.05, -\u20090.003) while the WISC intellectual quotient and its sub-scores (except processing speed index) showed a positive association with distance. Blood lead and urinary cadmium were negatively associated with the IQ total score and all sub-scores, although not reaching the significance level. Hair manganese and blood lead was positively associated with the CANTAB between errors of spatial working memory (\u3b2 2.2; 95% CI 0.3, 3.9) and the reaction time of stop signal task (\u3b2 0.05; 95% CI 0.02, 0.1) respectively. All the other CANTAB neurocognitive tests did not show to be significantly influenced by metal exposure. The highest socio-economic status showed about five points intellectual quotient more than the lowest level on average (\u3b2 4.8; 95% CI 0.3, 9.6); the interaction term between blood lead and the socio-economic status showed a significant negative impact of lead on working memory at the lowest socio-economic status level (\u3b2 -\u20094.0; 95% CI -6.9, -\u20091.1). CONCLUSIONS: Metal exposure and the distance from industrial emission was associated with negative cognitive impacts in these children. Lead exposure had neurocognitive effect even at very low levels of blood lead concentration when socio-economic status is low, and this should further address the importance and prioritize preventive and regulatory interventions

OPTIMIZATION OF THE ANALYTICAL PROCEDURE FOR CR, CU, NI, AND PB DETERMINATION BY ICP-AES IN MUNICIPAL LANDFILL LEACHATES

An ICP-AES-based procedure to determine Cr, Cu, Ni, and Pb in landfill leachates was optimized. Comparison of the performance of two different concentric nebulizers (Meinhard and Zr-cone Jobin-Yvon) was considered both with and without pretreatment of the samples. Moreover, calibration by standards of different composition was used and compared to the standard addition procedure. The matrix effect depended on the different experimental conditions. By using the Zr-cone Jobin-Yvon nebulization system and calibrating with standard solutions of saline contents similar to those of the leachate the matrix effect was satisfactorily compensated. Deviations from the reference concentration values were, in this case, less than 5% for all the metals considered. (C) 1994 Academic Press, Inc

Biomonitoring of traffic police officers exposed to airborne platinum

Background: Over the past two decades there has been a substantial increase in environmental levels of palladium, platinum, and rhodium, the platinum group elements (PGEs), due to the widespread use of catalytic converters for automotive traction. Aim: To evaluate urinary platinum levels in occupationally exposed subjects. Methods: A total of 161 employees from the Rome City Police Force were studied; 103 were traffic police involved in controlling streets with an average flow of vehicles, while the remaining 58 were control subjects engaged only in office work. Platinum quantification in the urine samples of these subjects was carried out by sector field inductively coupled plasma mass spectrometry. Results: There were no statistically significant differences between platinum levels in the group of subjects engaged in traffic control and the control group (4.45 (2.42) ng/l v 4.56 (2.84) ng/l, respectively). Conclusions: Urinary levels were found to be higher than those reported for other urban populations, thus showing a progressive increase in human exposure to Pt

Quantification of trace elements by sector field inductively coupled plasma mass spectrometry in urine, serum, blood and cerebrospinal fluid of patients with Parkinson's disease

To assess whether levels of trace metals and oxidative species are involved in Parkinson's disease (PD), At, Be, Cd, Co, Cr, Ha, Mn, Ni, Pb and V were measured in urine, serum, blood and cerebrospinal fluid (CSF) and serum peroxides and antioxidant capacity were determined in 26 patients with PD and 13 control subjects. The quantification of metals was based on the 1 + 4 water dilution of CSF, serum and urine, the acid-assisted microwave digestion under atmospheric pressure of blood and final determination by sector field inductively coupled plasma mass spectrometry (SF-ICP-MS). Results indicated a significant increase of Pb and V concentrations in blood and urine (P less than or equal to 0.03, in both cases) related to the disease. Parkinson disease also seemed to be closely associated (P less than or equal to 0.003) with a reduction in levels of Al, Cd, Hg and Pb in serum and of Cd, Co, Cr, Hg, Pb in CSF As regards Mn, a lower mean concentration was found in the CSF and whole blood of PD patients than in control group, although this trend was not statistically significant. Levels of peroxides were also increased (P less than or equal to 0.001), while antioxidant capacity was lower (P less than or equal to 0.002) in PD patients than in controls. (C) 2004 Published by Elsevier B.V

Metal changes in CSF and peripheral compartments of parkinsonian patients

Background: Involvement of metals in the risk of developing Parkinson's disease (PD) has been suggested. In the present study, concentration of metals in cerebrospinal fluid (CSF), blood, serum, urine and hair of 91 PD patients and 18 controls were compared. Methods: Blood and hair were microwave digested, while CSF, serum and urine were water-diluted. Elements quantification was achieved by Inductively Coupled Plasma Atomic Emission Spectrometry and Sector Field Inductively Coupled Plasma Mass Spectrometry. Results: Some metal imbalances in PD were observed: i), in CSF, lower Fe and Si; ii), in blood, higher Ca, Cu, Fe, Mg and Zn; iii), in serum, lower Al and Cu; iv), in urine, lower Al and Mn, higher Ca and Fe; and v), in hair, lower Fe. The ROC analysis suggested that blood Ca, Fe, Mg and Zn were the best discriminators between PD and controls. In addition, hair Ca and Mg were at least 1.5 times higher in females than in males of patients and controls. A decrement with age of patients in hair and urine Ca and, with less extent, in urine Si was observed. Magnesium concentration in CSF decreased with the duration and severity of the disease. Elements were not influenced by the type of antiparkinsonian therapy. Conclusions: Variation in elements with the disease do not exclude their involvement in the neurodegeneration of PD. (C) 2006 Elsevier B.V. All rights reserved

Calcium, copper, iron, magnesium, silicon and zinc content of hair in Parkinson's disease

The aetiology of Parkinson's disease (PD) is still unknown, but some hypotheses have focused on the imbalances in body levels of metals as co-factors of risk. To assess whether hair could be a reliable marker of possible changes, calcium (Ca), copper (Cu), iron (Fe), magnesium (Mg), silicon (Si) and zinc (Zn) were determined in hair from 81 patients affected by PD and 17 age-matched controls. Care was taken to eliminate external contamination of the hair by thorough washing. Digestion of the matrix was achieved by an acid-assisted microwave procedure. Quantification of the elements was performed by inductively coupled plasma atomic emission spectrometry. Results indicated significantly lower levels of Fe in the hair of patients (p = 0.018) compared with controls. Ca and Mg levels were slightly lower while Zn levels were higher in patients, although these differences were not significant; neither were variations in Cu and Si. Ca and Mg were at least 1.5 times higher in females than in males in both controls and patients. In addition, Ca correlated positively with Mg in both groups and in both sexes (p-value always less than 0.03), and negatively with age in patients (p < 0.01). Finally, element levels did not correlate with either the duration or the severity of the disease or with anti-Parkinson treatment. (c) 2005 Elsevier GmbH. All rights reserved

Monitoring of chemical elements and oxidative damage in patients affected by Alzheimer's disease

The haematic concentration of 26 metals and the oxidative damage in 60 patients (20 males and 40 females) affected by Alzheimer's disease and 44 healthy individuals (33 males and 11 females) were compared. In patients, the following significant (p ≤ 0.05) discrepancies were found: i) increment of Ca, Cd, Hg, Mg, Si and Sn, and decrement of Al, Co, Fe and Zn in serum; ii) higher concentrations of Cu, Li, Mn, Sn and Zr and lower of Fe, Hg, Mo in blood; iii) overproduction of oxidant species (SOS) and decrease of the anti-oxidant capacity (SAC) (p ≤ 0.001, for both). Variables that, joined, better discriminated between patients and controls resulted to be Si, SOS, SAC, Co, Ca, Al in serum (94% of cases correctly classified) and Cu, Zr, Mo and Fe in blood (90% of cases properly categorized)