Modelling the distribution of arsenic and mercury in urine using chemometric tools

Abstract

Among the heavy metals and other chemicals that contaminate the immediate environment of all gold mining communities, Arsenic and Mercury compounds are some of the most prevalent, exposing residents to their health risks. This menace is the result of the mining activities, particularly, Artisanal and Small-scale gold mining, in these communities. Among the mining areas in Ghana, Artisanal and small-scale gold mining is a recent activity only in the Eastern Region, particularly in the Aduasena, Afosu, Intronang, Hweakwae, New Abirem, Mamano and Hamlets communities. The objective of this research is to investigate the levels of Arsenic and Mercury in the residents of these seven communities using spectroscopic analysis of their urine samples and to identify which gender and at what age does any resident in a typical Ghanaian mining community stand most endangered by the levels of these contaminants. Samples of first urine void of residents upon waking up in the morning were taken, digested with nitric acid and analysed for the concentrations of Arsenic and Mercury using the Perkin Elmer PinAAcle 900T Graphite Furnace AAS. The spectroscopic analysis of the urine samples showed that more than 20% of the residents had concentrations of Arsenic higher than the (normal) recommended level, with some reaching as high as 221 $\mu g/L$ for Arsenic and 3.90 $\mu g/L$ for mercury. Statistical analysis of the results showed that the levels of both Arsenic and Mercury seem to increase with increasing age, despite some extremely high concentrations for arsenic in the Aduasena youth between 31 and 40 years. This trend indicates that males were seen to be more at risk from these contaminants, with the youth between 11 and 20 years standing most endangered.

Keywords:

• modeling
• distribution
• arsenic
• mercury
• urine
• chemometrics

PUBLIC INTEREST STATEMENT

Artisanal and small-scale gold mining (ASGM) is a type of mining done by individuals or cooperatives with minimal or no mechanization. Most of those involved in the activities are low-income earners and therefore the trade serves as the most promising income opportunity available. The activities of ASGM is detrimental to the environment as a result of the crude methods employed. This environmental degradation as a result of ASGM must be checked and banned governments all over the world. More so the techniques involved in the processing of the gold-bearing rocks are crude and dangerous. It also involves the application of mercury which is a very dangerous element. During the processing, mercury sips into waterbodies and aquatic systems which when ingested could results in fatalities in humans and other living organisms. Therefore, ASGM is to be ban completely and governments must regulate their activities.

Competing Interests

Authors declare no competing interests.

Acknowledgement

The Authors wish to express their profound gratitude to the Central Laboratory of Kwame Nkrumah University of Science and Technology (KNUST) Kumasi, Ghana for their support. The Authors are also grateful to Laboratory Technicians of the Departments of Chemical Engineering and Chemistry, KNUST for invaluable support during the analysis of the samples.

Additional information

Funding

The authors received no direct funding for this research.

Notes on contributors

Bernard Adu-Poku

Mr Bernard Adu-Poku is a holds a Masters degree in Chemical Engineering from Kwame Nkrumah University of Science and Technology Kumasi Ghana. He is Currently looking for a PhD position. His research interest includes Reaction Engineering, thermodynamics, mass transfer processes and Biochemical Engineering.

Nana Asiedu

Mr Bernard Adu-Poku is a holds a Masters degree in Chemical Engineering from Kwame Nkrumah University of Science and Technology Kumasi Ghana. He is Currently looking for a PhD position. His research interest includes Reaction Engineering, thermodynamics, mass transfer processes and Biochemical Engineering.

Osei Akoto

Osei Akoto is a Senior Lecturer in Chemical Engineering in Kwame Nkrumah University of Science and Technology. His research interest includes Reactor Modeling, Synthesis, Optimization and Simulation, Heterogeneous Catalysis and Biochemical Engineering. Currently, he is working on the development of new catalyst to convert biomass to specialty chemicals.

James Ataki

James Ataki is a Professor in Chemistry in the department of Chemistry in the Kwame Nurumah University of Science and Technology Kumasi Ghana. His research interest includes Environmental Chemistry, Environmental Impact Assessment (EIA) and Photochemistry.