Exposure Risk Characterization Research Articles

Risk characterization of human exposure to polycyclic aromatic hydrocarbons in vulnerable groups

Nowadays, anthropogenic activities are a significant source of environmental pollutants at an alarming rate. Polycyclic aromatic hydrocarbons (PAHs) are widely spread and well-known mutagenic and carcinogenic legacy pollutants of public health concern. In underdeveloped countries like Brazil, limited data are available in the scientific literature on the risk assessment of exposure to PAHs, leading to a risk underestimation, especially in the vulnerable groups of the population. In the current investigation, we have measured seven PAH metabolites in healthy vulnerable groups (n = 400), including pregnant and lactating women, newborns, and children. Besides, according to the United States Environmental Protection Agency (US.EPA) guidelines, the risk characterization of this exposure was performed by calculating estimated daily intake, hazard quotient, hazard index, and cancer risk. The highest levels and detection rates for all metabolites were found in pregnant women, with 15.71 ng/mL for the ∑OH-PAHs, presumably due to the increased metabolic rate related to pregnancy. The lowest ∑OH-PAHs were detected in infants, with 2.33 ng/mL due to unmatured metabolism. When analyzing the health hazards, the non-carcinogenic risk - as a sum of all PAH metabolites, we observed a health risk (in all groups) above the limit that the US.EPA considers without significant potential health risk. Regarding cancer risks, benzo[a]pyrene levels in all the groups indicated a potential risk. In general, higher levels of potential cancer risk were observed for lactating women, which implies risks to them and their infants. Low molecular weight PAHs (naphthalene, fluorene, and phenanthrene) are associated with acute toxic effects. Their high detection rate (i.e., naphthalene: 100 %) demonstrates their extensive exposure, making these PAHs a priority for human biomonitoring. Besides, benzo[a]pyrene is carcinogenic to humans, being also important to monitor its levels since our risk assessment showed a high cancer risk to this PAH.

Burden of Disease (BoD) Assessment to Estimate Risk Factors Impact in a Real Nanomanufacturing Scenario.

An industrial nanocoating process air emissions impact on public health was quantified by using the burden of disease (BoD) concept. The health loss was calculated in Disability Adjusted Life Years (DALYs), which is an absolute metric that enables comparisons of the health impacts of different causes. Here, the health loss was compared with generally accepted risk levels for air pollution. Exposure response functions were not available for Ag nanoform. The health loss for TiO2 nanoform emissions were 0.0006 DALYs per 100,000 persons per year. Moreover, the exposure risk characterization was performed by comparing the ground level air concentrations with framework values. The exposure levels were ca. 3 and 18 times lower than the derived limit values of 0.1 μg-TiO2/m3 and 0.01 μg-Ag/m3 for the general population. The accumulations of TiO2 and Ag nanoforms on the soil top layer were estimated to be up to 85 μg-TiO2/kg and 1.4 μg-Ag/kg which was considered low as compared to measured elemental TiO2 and Ag concentrations. This assessment reveals that the spray coating process air emissions are adequately controlled. This study demonstrated how the BoD concept can be applied to quantify health impacts of nanoform outdoor air emissions from an industrial site.