Health Risk Assessment of Indoor Dust-Associated Heavy Metals Obtained from Four Philippine Public Hospitals

Abstract

Heavy metal concentrations in indoor dusts can have significant human health risks through inhalation, ingestion, and dermal absorption. The present study aims to assess the health risks of four heavy metal concentrations (Pb, Cd, Hg, and As) obtained in indoor dust from selected public hospitals in populous cities situated in Metro Manila and Batangas province. Non-carcinogenic risks were inferred by calculating the hazard quotients (HQ) and hazard indices (HI) of the heavy metals, while carcinogenic risks were stipulated by obtaining their cancer risk values. Results show that Ospital ng Maynila possessed 1.44 mgkg-1 Pb, 0.02 mgkg-1 Cd, 0.74 mgkg-1 Hg, and 2.00 mgkg-1 As; Philippine General Hospital indoor dust yielded 0.53 mgkg-1 Pb, 0.48 mgkg-1 Hg, and 1.80 mgkg-1 As; Laurel Memorial Hospital had 0.23 mgkg-1 Pb, 0.35 mgkg-1 Hg, and 2.50 mgkg-1 As; and Lipa City District Hospital-Granja generated 0.15 mgkg-1 Pb, 0.19 mgkg- 1 Hg, and 1.50 mgkg-1 As. These concentrations all yielded HQ<1 and HI<1, indications of their insufficiency to induce significant non-carcinogenic health detriments. Analysis on the carcinogenic heavy metals, Cd and As, showed cancer values on the lower limit of the carcinogenicity threshold, 1×10-6 - 1×10-4. This concludes that as of date, there is no immediate concern over the heavy metal concentrations in the sample sites. However, additional caution is advised for people who are susceptible for long-term exposure due to the observed high carcinogenic risk that comes with chronic heavy metal dosage.