Related Experiment Video
Updated: Jun 17, 2026

07:05
Use of Autometallography to Localize and Semi-Quantify Silver in Cetacean Tissues
Published on: October 4, 2018
Study of metals transfer from environment using teeth as biomonitor
J D T Arruda-Neto1, L P Geraldo, G R Prado
1Physics Institute, University of São Paulo, São Paulo-SP, Brazil. arruda@if.usp.br
Environment International
|January 8, 2010
Summary
This study examined chronic metal exposure in children and adults near São Paulo's Guarapiranga dam. Lead and cadmium levels were concerningly high, especially in younger individuals, indicating potential health risks from environmental contamination.
Area of Science:
- Environmental Health
- Toxicology
- Public Health
Background:
- The Guarapiranga dam supplies water to 25% of São Paulo city.
- Alleged contamination in the surrounding area raises public health concerns.
- Chronic metal incorporation in vulnerable populations requires investigation.
Purpose of the Study:
- To assess chronic metal incorporation in individuals residing near the Guarapiranga dam.
- To determine the concentrations of various metals (Pb, Cd, Fe, Zn, Mn, Ni, Cr) in teeth.
- To analyze the relationship between metal concentrations and age.
Main Methods:
- Collection of 59 teeth from individuals aged 7 to 60 years.
- Quantification of metal concentrations using Atomic Absorption Spectrophotometry.
- Analysis of metal levels in relation to individual age.
Main Results:
- All measured metals showed peak concentrations in individuals aged 7-10 years, decreasing with age.
- Lead (Pb) and cadmium (Cd) concentrations were notably high, approaching global upper limits.
- Age-related patterns suggest cumulative exposure and dietary influences.
Conclusions:
- Individuals near the Guarapiranga dam exhibit significant chronic metal incorporation.
- Younger populations show higher metal burdens, particularly lead and cadmium.
- Environmental contamination and dietary habits are critical factors influencing metal exposure and health risks.
Related Concept Videos
Microbes and Other Elemental Cycles
Microbial activity plays a pivotal role in the biogeochemical cycling of iron and manganese, especially at the redox gradients characteristic of stratified aquatic environments. These cycles are driven by microbial transformations between oxidized and reduced forms of the metals, allowing organisms to exploit them for metabolic energy and structural purposes.Iron Cycling Across Redox GradientsIn neutral, oxygen-rich surface waters, iron is predominantly found in its oxidized, insoluble ferric...
Voltammetry: Stripping Methods
Anodic Stripping Voltammetry (ASV), Cathodic Stripping Voltammetry (CSV), and Adsorptive Stripping Voltammetry (AdSV) are electrochemical techniques used to determine trace amounts of analytes in solution. These methods involve applying a potential to an electrode and measuring the resulting current.
Anodic Stripping Voltammetry (ASV)
ASV is used to determine metals and metalloids at trace levels. It involves two steps: deposition and stripping. First, a negative potential is applied to the...
Anodic Stripping Voltammetry (ASV)
ASV is used to determine metals and metalloids at trace levels. It involves two steps: deposition and stripping. First, a negative potential is applied to the...
Microbial Leaching
Microbial leaching, also known as bioleaching, is an environmentally favorable method for extracting metals from low-grade ores using specific microorganisms. This biotechnological approach is particularly valuable for mining operations targeting copper, gold, and uranium, where traditional extraction methods may be economically or environmentally impractical.Copper Leaching and Microbial CatalysisIn copper bioleaching, crushed ore is arranged into heaps and irrigated with a dilute sulfuric...
Electrodeposition
Electrodeposition is a technique used to separate an analyte from interferents by electrochemical processes. Here, the analyte is a metal ion that can be deposited on an electrode immersed in the sample solution. The electrochemical setup consists of an anode and a cathode. When an electric current is applied to the setup, oxidation occurs at the anode. At the cathode, which consists of a large metal surface, metal ions undergo reduction and deposit onto the surface.
Electrodeposition can...
Electrodeposition can...
Effects of EDTA on End-Point Detection Methods
Different methods, such as visual observance of metal-ion indicators, spectroscopic techniques, and potentiometric methods, can determine the endpoint of an EDTA titration.
In the visual method, metal-ion indicators (metallochromic dyes), which have distinct colors in their free and complex forms, are added to the mixture to signal the titration's end point. They form stable complexes with metal ions, but these complexes are weaker than the corresponding metal–EDTA complexes. As a result, EDTA...
In the visual method, metal-ion indicators (metallochromic dyes), which have distinct colors in their free and complex forms, are added to the mixture to signal the titration's end point. They form stable complexes with metal ions, but these complexes are weaker than the corresponding metal–EDTA complexes. As a result, EDTA...

