Bioaccessible arsenic in soil of thermal areas of Viterbo, Central Italy: implications for human health risk

Abstract

Thermal waters near the city of Viterbo (Central Italy) are known to show high As contents (up to 600 µg/l). Travertine is precipitated by these waters, forming extended plateau. In this study, we determine the As content, speciation and bioaccessibility in soil and travertine samples collected near a recreational area highly frequented by local inhabitants and tourists to investigate the risk of As exposure through accidental ingestion of soil particles. (Pseudo)total contents in the studied soils range from 17 to 528 mg/kg, being higher in soil developed on a travertine substrate (197 ± 127 mg/kg) than on volcanic rocks (37 ± 13 mg/kg). In travertines, most As is bound to the carbonatic fraction, whereas in soil the semimetal is mostly associated with the oxide and residual fractions. Accordingly, bioaccessibility (defined here by the simplified bioaccessibility extraction test, SBET; Oomen et al., 2002.) is maximum (up to 139 mg/kg) for soil developed on a travertine substrate, indicating a control of calcite dissolution on As bioaccessibility. On the other hand, risk analysis suggests a moderate carcinogenic risk associated with accidental soil ingestion, while dermal contact is negligible. By contrast, ingestion of thermal water implies a higher carcinogenic and systemic health risk.

Arsenic: A Review on a Great Health Issue Worldwide

“…Arsenic comprises about 1.5 ppm (0.00015%) of the earth's crust and is the 53rd most abundant element. Typical background concentrations of arsenic do not exceed 100 mg/kg in soil [32], and 10 µg/L in freshwater [33,34]. The maximum tolerance limit for arsenic in drinking and public water is 10 µg/L [35].…”

Interplay between abiotic and microbial biofilm‐mediated processes for travertine formation: Insights from a thermal spring (Piscine Carletti, Viterbo, Italy)

“…Piscine Carletti (hereafter named PC ; also referred to as Bullicame 3 or Bullicame West ; Duchi et al, 1985; Pentecost, 1995; Minissale et al, 2002; Di Benedetto et al, 2011; Rimondi et al, 2021) is located in a thermal area sited between the Central Apennines and Tyrrhenian coastline, few km west of the town of Viterbo (northern Latium, Central Italy; Figure 1). This region is characterized by (i) a Paleozoic–Triassic metamorphic basement, (ii) Mesozoic–Paleogene sedimentary rocks related to the Apennine orogenesis, and (iii) upper Mio‐Pleistocene sedimentary basins related to a post‐collisional extensional phase (Baiocchi et al, 2012; Piscopo et al, 2006) during which the Vicano–Cimino Volcanic District (VCVD) formed (Tassi et al, 2015, and references therein).…”

Mercury accumulation efficiency of different biomonitors in indoor environments: the case study of the Central Italian Herbarium (Florence, Italy)

“…Environmental monitoring and quantification of potentially toxic elements is often carried out by instrumental devices (Mikkelsen et al 2005 ; Cabassi et al 2017 ; Rimondi et al 2022 ). Biomonitoring, i.e., the use of organisms as biomonitors to track changes in the environment and monitor air quality (Conti 2008 ; Friberg et al 2011 ; Aničić Urošević and Milićević 2020 ; Lattanzi et al 2020 ), is an alternative/complementary technique to support and integrate data from instrumental devices.…”