title: Chemical-based risk assessment and in vitro models of human health effects induced by organic pollutants in soils from the Olona Valley.
abstract: Risk assessment of soils is usually based on chemical measurements and assuming accidental soil ingestion and evaluating induced toxic and carcinogenic effects. Recently biological tools have been coupled to chemical-based risk assessment since they integrate the biological effects of all xenobiotics in soils. We employed integrated monitoring of soils based on chemical analyses, risk assessment and in vitro models in the highly urbanized semirural area of the Olona Valley in northern Italy. Chemical characterization of the soils indicated low levels of toxic and carcinogenic pollutants such as PAHs, PCDD/Fs, PCBs and HCB and human risk assessment did not give any significant alerts. HepG2 and BALB/c 3T3 cells were used as a model for the human liver and as a tool for the evaluation of carcinogenic potential. Cells were treated with soil extractable organic matters (EOMs) and the MTS assay, LDH release and morphological transformation were selected as endpoints for toxicity and carcinogenicity. Soil EOMs induced dose-dependent inhibition of cell growth at low doses and cytotoxicity after exposure to higher doses. This might be the result of block of cell cycle progression to repair DNA damage caused by oxidative stress; if this DNA damage cannot be repaired, cells die. No significant inductions of foci were recorded after exposure to EOMs. These results indicate that, although the extracts contain compounds with proven carcinogenic potential, the levels of these pollutants in the analyzed soils were too low to induce carcinogenesis in our experimental conditions. In this proposed case study, HepG2 cells were found an appropriate tool to assess the potential harm caused by the ingestion of contaminated soil as they were able to detect differences in the toxicity of soil EOMs. Moreover, the cell transformation assay strengthened the combined approach giving useful information on carcinogenic potential of mixtures.
authors.affiliation: Laboratory of Environmental Chemistry and Toxicology, IRCCS - Istituto di Ricerche Farmacologiche Mario Negri, Via Giuseppe La Masa 19, 20156 Milan, Italy. Electronic address: diego.baderna@marionegri.it.
authors.forename: Diego
authors.initials: D
authors.lastname: Baderna
authors.forename: Andrea
authors.initials: A
authors.lastname: Colombo
authors.forename: Giorgia
authors.initials: G
authors.lastname: Amodei
authors.forename: Stefano
authors.initials: S
authors.lastname: Cantù
authors.forename: Federico
authors.initials: F
authors.lastname: Teoldi
authors.forename: Felice
authors.initials: F
authors.lastname: Cambria
authors.forename: Giuseppe
authors.initials: G
authors.lastname: Rotella
authors.forename: Fabrizio
authors.initials: F
authors.lastname: Natolino
authors.forename: Marco
authors.initials: M
authors.lastname: Lodi
authors.forename: Emilio
authors.initials: E
authors.lastname: Benfenati
mesh_terms: D000818:Animals; D041702:BALB 3T3 Cells / Q000187:drug effects; D049109:Cell Proliferation / Q000187:drug effects; D002471:Cell Transformation, Neoplastic / Q000139:chemically induced; D004249:DNA Damage / Q000187:drug effects; D056945:Hep G2 Cells / Q000187:drug effects*; D006801:Humans; D066298:In Vitro Techniques; D007558:Italy; D051379:Mice; D018570:Risk Assessment; D012987:Soil / Q000737:chemistry; D012989:Soil Pollutants / Q000633:toxicity*
chemical_list: D012987:Soil; D012989:Soil Pollutants
keywords: BaP; Benzo-a-pyrene; CDI; CTA; Cell transformation assay; DMSO; EOMs; Environmental toxicology; FBS; HCB; HRA; HepG2; Human risk assessment; MTS; PAHs; PCBs; PCDD/Fs; Soil pollutants; TF; [3-(4,5-dimethylthiazol-2-yl)-5-(3-carboxymethoxyphenyl)-2-(4-sulfophenyl)-2H-tetrazolium, inner salt; cell transformation assay; chronic daily intake; dimethylsulphoxide; extractable organic matters; fetal bovine serum; hexachlorobenzene; human risk assessment; polychlorinated biphenyls; polychlorinated dibenzodioxins and polychlorinated dibenzofurans; polycyclic aromatic hydrocarbons; transformation frequency