Human predisposition to cognitive impairment and its relation with environmental exposure to potentially toxic elements

Abstract

New lines of evidence suggest that less than 10% of neurodegenerative diseases have a strict genetic aetiology and other factors may be prevalent. Environmental exposures to potentially toxic elements appear to be a risk factor for Parkinson's, Alzheimer's and sclerosis diseases. This study proposes a multidisciplinary approach combining neurosciences, psychology and environmental sciences while integrating socio-economic, neuropsychological, environmental and health data. We present the preliminary results of a neuropsychological assessment carried out in elderly residents of the industrial city of Estarreja. A battery of cognitive tests and a personal questionnaire were administered to the participants. Multivariate analysis and multiple linear regression analysis were used to identify potential relationships between the cognitive status of the participants and environmental exposure to potentially toxic elements. The results suggest a relationship between urinary PTEs levels and the incidence of cognitive disorders. They also point towards water consumption habits and profession as relevant factors of exposure. Linear regression models show that aluminium (R = 38%), cadmium (R = 11%) and zinc (R = 6%) are good predictors of the scores of the Mini-Mental State Examination cognitive test. Median contents (µg/l) in groundwater are above admissible levels for drinking water for aluminium (371), iron (860), manganese (250), and zinc (305). While the World Health Organization does not provide health-based reference values for aluminium, results obtained from this study suggest that it may have an important role in the cognitive status of the elderly. Urine proved to be a suitable biomarker of exposure both to elements with low and high excretion rates.

Lead and zinc concentrations in household dust and toenails of the residents (Estarreja, Portugal): a source-pathway-fate model

“…S4 †), but the differences between indoor and outdoor samples are not signicant. The geology of the area is composed mainly of sandstones and clay deposits, where the two elements tend to be concentrated, 45,85 providing additional support to the natural origin earlier assigned for As. Furthermore, other crustal elements associated with PC3 (Table S3 †) include iron (Fe), Ga, niobium (Nb), and cobalt (Co), which support further the assumption that As and Mo, although enriched (Fig.…”

“…In the late 1990's the area was remediated and industrial wastes containing hazardous materials such as pyrite ashes, mercury-enriched muds, and organochlorine compounds, were buried and sealed near the complex. Nevertheless, recent studies have been reporting on elevated contents of environmental contaminants in natural media, namely mercury (Hg) in lake sediments, 43 As in soil and groundwater, 44,45 and PM10 in ambient air. 42 In recent years, several studies available from the literature have suggested that currently, vehicular traffic stands for a contributor of increasing importance to the quality degradation of the local environment.…”

“…42,46 Hot-dip galvanising for zinc coating or the production and assembly of carbon steel, stainless steel, and aluminium tubing are industrial processes taking place in the CCE likely to emit PTEs to the atmosphere. Indeed, the Zn concentrations reported in different studies focusing on groundwater, soils, home-grown foodstuffs and street dust 34,44,45 suggest elevated levels of environmental Zn in the region.…”

“…From the supplementary variables, strontium (Sr) is the only element associated with Group II (negative loading in PC2, Table S3 †). Since Sr is oen suggested as a suitable tracer of mineral dust and the local geology is composed mainly of sandstones and clay deposits that are enriched in B, 45,85 it is possible that anthropogenic particulate matter emitted to the atmosphere settles at ground-level where it mixes with mineral dust and/or soil. Hence, Group II probably represents a mixed biomass burning and anthropogenic pollution, with a contribution from mineral dust/soil.…”

The Cancer and Non-Cancer Risk of Santiago Island (Cape Verde) Population due to Potential Toxic Elements Exposure from Soils

“…They support agriculture and the main carbon reservoir of the terrestrial carbon cycle, they act as a sink for pollutants, protecting groundwater from pollution, and they are also used as construction material and support. Therefore, they have very important social, environmental, and economic functions [1,2].…”