# Assessment of Heavy Metal Distributions in Sand Beaches in the Maltese Islands
## 4 Conclusions  
Results obtained in this study provide a greater insight into heavy metal pollution in sand beaches located around the islands of Malta and Gozo. None of the concentrations documented were higher than those reported by other studies in the Mediterranean region. The highest heavy metal concentrations were listed for Ballut Reserve Bay, Rinella Bay, Riviera Bay, Marsalform Bay, and Ramla Bay. The highest number of outlier data points resulted from Ballut Reserve Bay, Ghadira Bay, and Ramla Bay. Pb and Zn content results were similar across different locations but none of the concentrations documented were the same across bays or across different coordinates. Outlier data points on different beaches were located close to human activity zones, which included food tilts and restaurants, water sport and leisure equipment renting tilts, and road runoff.  
A strong correlation between Fe and Mn was recorded, hinting towards a prevalent lithogenic origin of the two elements, possibly from rock erosion by sea waves, especially along the east coast of the islands where prevailing winds blow.  
Multivariate analysis results showed that Pb is possibly obtained from highly anthropogenic sources, while Cu and Zn have a mixed origin. Fe, Mn, and Sr are of a lithogenic  
Figure 5: Pie charts representing monomial potential ecological risk factor (Ei) values for different heavy metals across sand beaches in Malta and Gozo.  
origin. Cluster analysis grouped sampling points into four main groups gathered according to the concentration levels of the heavy metals studied across different bays. High Sr content was related to samples collected from Pretty Bay and St. George's Bay; higher Fe, Cu, Mn, and Zn content was linked to Rinella Bay, Golden Bay, Gnejna Bay, Riviera Bay, and Ramla Bay; the lowest Pb content was related to Golden Bay.  
Such results tie in with the health risk assessment and potential ecological risk assessment results obtained. Very low Hazard Index and Cancer Risk Index values for adults and children resulted from the calculations performed. Thus, persons frequenting beaches are not at a risk of non-carcinogenic and carcinogenic effects by ingesting and having long-term exposure to such heavy metals present in sand beaches. Nonetheless, although the beaches studied are not contaminated overall, a considerable ecological risk of contamination is present because of Cu content and a moderate ecological risk is caused by Pb content found mainly in Ballut Reserve Bay, Rinella Bay, and Marsalform Bay.  
Further scientific analysis is suggested to assess these outcomes in detail and make the necessary decisions to minimise toxicity levels on sand beaches to reduce the ecological risk.  
The following supporting information can be downloaded at [[https://www.mdpi.com/article/10.3390/app12147192/s1](https://www.mdpi.com/article/10.3390/app12147192/s1)]([https://www.mdpi.com/article/10.3390/app12147192/s1](https://www.mdpi.com/article/10.3390/app12147192/s1)): Figure S1: Heavy Metal Content Distribution around Malta and Gozo; Figure S2: Location of Studied Beaches.  
Conceptualization, F.L. and I.M.A.; methodology F.L. and I.M.A.; data curation, F.L., I.M.A., and C.C.; writing--original draft preparation, C.C.; writing--review and editing, C.C. and F.L.; supervision, F.L.; project administration, F.L.; funding acquisition, C.C. and F.L. All authors have read and agreed to the published version of the manuscript.  
The APC was funded by Malta College of Arts, Science and Technology (MCAST).  
Not applicable.  
The authors declare no conflict of interest.