Arsenic and its compounds were classified as human carcinogens by IARC, because of their role in the onset and the progression of several neoplasms: liver, lung, bladder, prostate and skin cancer. If many studies shed to light on the existence of a strong association between As and cancer at chronic exposure to high metalloid concentrations (>150 µg/L), much remains to be clarified on the effects of low-moderate exposure, such as those occurring in Italy. The aim of this retrospective cohort study is to focus on the role of Arsenic in the pathogenesis of lung cancer, as one of the most impacting neoplasms in terms of incidence and prevalence (40.000 new diagnoses in Italy in 2017), in Viterbo Province, central Italy.~Because of its high toxicity and its ubiquitous distribution, that earned the metalloid the first in the Priority list by ATSDR, thus being a main issue in Public Health.~Materials and Methods From 1st January 2006 to 31st December 2012 all the inhabitants, residing in one of the 60 municipalities of Viterbo Province (around 320,279 people) were enrolled. Incident cases of lung cancer, recorded by Viterbo Cancer Registry, occurring during the period, were considered as primary outcome. People residing in municipalities with Arsenic drinking water concentrations over legal threshold (10 µg/L), as provided by Arpa Lazio, were considered as exposed.~Risk difference in developing lung cancer among exposed and not exposed was estimated by Relative Risk (RR) and Attributable Risk (AR).
Aim of the study was to assess any associations between chronic exposure by drinking water to Arsenic and onset of lung cancer, using a retrospective cohort study design.~Incident cases of lung cancer from 1st January 2006 to 31st December 2012, recorded by Viterbo Cancer Registry, occurring during the period, were considered as primary outcome. People residing in municipalities with Arsenic drinking water concentrations over legal threshold (10 µg/L) were considered as exposed.