Assessment of heavy metal content in sand beaches in the Maltese Islands using EDXRF spectrometry.

Christine Costa

Frederick Lia, Emanuel Sinagra

Faculty of Science, Department of Chemistry, University of Malta, Msida   |  christine.costa.04@um.edu.mt

 

Introduction

High toxicity levels in the natural environment lead to degradative effects to the ecosystem and human health. Heavy metal toxicity increases the risk of neurological disorders and cancer related disease in humans, and abnormal growth in plants. Land and marine industrialization, road development, agricultural and farming practices, runoff, waste treatment, together with natural activity including geological erosion and metallic evaporation from land are all linked to the rise of heavy metal toxicity levels on beaches. These concentrations increase by accumulation over time and by variations in seasons due to the changes in human activities and due to weather effects. Other studies in the Mediterranean region have established that the studied area is highly affected by human activities which vary according to the seasons and concluded that heavy metal concentration studies should be included in environmental monitoring programs.

Methodology

Sand samples were collected at the end of summer from 5 different beaches in Malta and Gozo. Sampling points were planned along linear transects orthogonal to the shoreline mapping most of each beach surface. A total of 3 samples were gathered at different depths at each sampling point – at the surface, at 10 cm depth and at 20 cm depth. Each of the 160 samples were dried at 70 °C for approximately 24 hours until constant mass was achieved. Sand was sieved  to retain granules up to 2 mm in size. Some 25 ± 0.1 g of each sample in loose powder form was levelled in the respective plastic cups lined with mylar thin-film spectro-membrane and analysed using Bruker S2 Ranger EDXRF.