Links between Cognitive Status and Trace Element Levels in Hair for an Environmentally Exposed Population: A Case Study in the Surroundings of the Estarreja Industrial Area

Abstract

In the present study, trace elements (TE) levels were evaluated in scalp hair along the continuum from healthy subjects (HS) to patients suffering from subjective memory concerns (SMC), and/or mild cognitive impairment (MCI), and those with already installed dementia (DEM) in order to: (i) assess the effects of environmental and lifestyle factors on TE concentrations and (ii) evaluate the analyzed elements as possible diagnostic biomarkers for the disease. The study involved 79 mainly permanent residents, >55 years old, from the city of Estarreja (northern Portugal), a former industrial area. The health status of the participants was assessed by means of a complete socio-demographic questionnaire and through cognitive screening tests, namely the Mini-Mental State Examination (MMSE). The test scores were categorized and used in the statistical analysis. Hair samples were collected and analyzed by inductively coupled plasma-mass spectrometry (ICP-MS) ICP-MS for selected TE. Dementia appears to be associated with higher age, the female gender, lower education level, and longer residence time in the study area. In addition, most of the participants diagnosed with dementia frequently consume home-grown foodstuffs, some irrigated with contaminated well water. The calculation of the TE enrichment factors of soil samples collected in kitchen gardens/small farms in the vicinity of the Estarreja Chemical Complex (ECC) reinforces the degree of Hg soil contamination in the area, due to anthropogenic sources that can be a source for the population Hg exposure route among others. Mercury levels in hair differed significantly between the four individual groups (HS, SMC, MCI, and DEM), increasing from healthy to dementia participants. Improved diagnostic results can be obtained using hair TE signatures coupled with MMSE scores. This strategy may prove useful for predictive diagnosis in population screening for cognitive impairment.

Community Preparation and Vulnerability Indices for Floods in Pahang State of Malaysia

“…LVI techniques may help officials to refine and focus policies that respond to the specific needs of households and the geographic areas in which they are located. For example, using vulnerability indices/indicators, policymakers can plan mitigation and adaptation strategies [8,12,13] and compare monitored conditions of vulnerability over time and in the different areas, establishing where resources need to be allocated [14,15].…”

Identification Framework of Contaminant Spill in Rivers Using Machine Learning with Breakthrough Curve Analysis

“…where γ is the complexity of tree leaf in the DT, T is the number of leaves in the DT, λ is the scale parameter, and w is the scores vector of leaves in the DT. By substituting Equation 14into Equation 12, the objective function is described as Equation (15). Then, the objective function can be simplified to Equation (16), by taking the second-order Taylor expansion:…”

“…However, inverse tracking of the contaminant source is a problem, due to the lack of observed data and complexity of the mixing processes in a natural river. In order to overcome this limitation, a number of methods for the identification of contaminant sources have been suggested, mainly in the groundwater system; these use various techniques, such as optimization, geostatistical simulations, analytical solutions, and data-driven models [4][5][6][7][8][9][10][11][12][13][14][15]. Although contaminant source identification problems in both rivers and groundwater have a similar purpose, applying the methods developed for groundwater to rivers is challenging, due to the difference in flow and mixing characteristics between groundwater and rivers.…”

Associations between Trace Elements and Cognitive Decline: An Exploratory 5-Year Follow-Up Study of an Elderly Cohort

“…Human contamination may result from various pathways, namely, through inhalation of contaminated air/ambient particulate matter, ingestion of contaminated soil/dust, water and foodstuffs (such as agriculture crops, meat, and seafood), and dermal absorption of TE present in soil/dust [ 10 , 32 , 33 ]. The toxicity of each TE is dependent on the route and absorbed dose, which is in turn dependent on the concentration and duration of exposure [ 34 ]. Furthermore, each TE has a specific half-life, and the elimination of different elements from the body widely varies [ 35 ].…”