Heavy Metals in Groundwater of Southern Italy: Occurrence and Potential Adverse Effects on the Environment and Human Health.

This study reports the data on the contamination caused by heavy metals in the groundwater of the Campania Plain (CP) in Southern Italy. A total of 1093 groundwater samples were obtained from the following aquifers: coastal plains (GAR, VCP, VES, SAR, and SEL), volcanic districts (PHLE and VES), and carbonate massifs (MAS and LAT). In this study, the investigation depth ranged from 5 m (GAR) to 200 m (PHLE). The sequence of heavy metal content in groundwater samples was B > Fe > Al > Mn > Zn > Ba > Ni > As > Cu > V > Se > Pb > Cd. The heavy metal pollution index (HPI) and heavy metal evaluation (HEI) demonstrated that the study areas in which groundwater samples were sampled are not risk zones. Moreover, health risk assessment shows that hazard index (HI) values for heavy metals were found to be significantly low in groundwater samples. In non-carcinogenic risk evaluation for the adult group, the risk was low, whereas for children and infants, the risk was >1 for arsenic alone. Carcinogenic risk assessment (CR) was found lower for adults, children, and infants. The Jenks optimization method was used to evaluate the distribution of heavy metals in the groundwater of CP, and the principal component analysis technique (PCA) was employed to determine the source of heavy metals, and it was found that mixed sources (natural and anthropogenic) may be responsible for heavy metals presence.