Characterization of indoor dust from Brazil and evaluation of the cytotoxicity in A549 lung cells

Abstract

Over the past decade, ambient air particulate matter (PM) has been clearly associated with adverse health effects. In Brazil, small and poor communities are exposed to indoor dust derived from both natural sources, identified as blowing soil dust, and anthropogenic particles from mining activities. This study investigates the physicochemical and mineralogical composition of indoor PM10 dust samples collected in Minas Gerais, Brazil, and evaluates its cytotoxicity and inflammatory potential. The mean PM10 mass concentration was 206 μg/m(3). The high dust concentration in the interior of the residences is strongly related to blowing soil dust. The chemical and mineralogical compositions were determined by ICP-OES and XRD, and the most prominent minerals were clays, Fe-oxide, quartz, feldspars, Al(hydr)oxides, zeolites, and anatase, containing the transition metals Fe, Cr, V, Ni, Cu, Zn, Ti, and Mn as well as the metalloid As. The indoor dust samples presented a low water solubility of about 6 %. In vitro experiments were carried out with human lung alveolar carcinoma cells (A549) to study the toxicological effects. The influence of the PM10 dust samples on cell viability, intracellular formation of reactive oxygen species (ROS), and release of the pro-inflammatory cytokine IL-8 was analysed. The indoor dust showed little effects on alamarBlue reduction indicating unaltered mitochondrial activity. However, significant cell membrane damage, ROS production, and IL-8 release were detected in dependence of dose and time. This study will support the implementation of mitigation actions in the investigated area in Brazil.

Particle pollution in Rio de Janeiro, Brazil: Increase and decrease of pro-inflammatory cytokines IL-6 and IL-8 in human lung cells

“…This was attributed to the re-suspension of outdoor dust and living conditions (Deschamps et al, 2013) which showed toxic and pro-inflammatory responses (IL-8 release) of high concentrations of indoor dust particles: 250–500µg/ml and 100–500µg/ml, respectively. In fact, higher asthma symptoms (wheezing) were reported in 28.5% of school students (Camargos et al, 1999).…”

Potentially harmful elements in house dust from Estarreja, Portugal: characterization and genotoxicity of the bioaccessible fraction

“…The arithmetic means, geometric means and medians of all analyzed PHEs in the 5 studied dust samples were calculated. Table 1 shows values for the 16 PHEs under study and compares the PHE concentrations with those reported in the literature (Chattopadhyay et al 2003;Chen et al 2014;Deschamps et al 2013;Kurt-Karakus 2012;Lisiewicz et al 2000;Rasmussen et al 2001). Further data on PHE concentrations in the full set of indoor dust samples collected from 19 private households in the city of Estarreja are provided in the form of supplementary material (Table S2).…”

“…They quantified the toxicity by evaluating the excess lifetime cancer risk and some assessed the in vitro cytotoxic and genotoxic potentials of organic extracts by using bacterial mutagenic assays such as the Ames test, SOS chromotest and Salmonella assay (Kang et al 2013(Kang et al , 2011Maertens et al 2008;Pohren et al 2012;Wang et al 2013a, b). Likewise, the toxicity of PHEs from house dust has been investigated using either the evaluation of excess lifetime cancer risk or cytotoxicity tests (Chen et al 2014;Deschamps et al 2013;Granero and Domingo 2002;Kurt-Karakus 2012). However, the ingested dose was used as the relevant measure to assess the health risk and the oral bioavailability of the PHEs was not estimated.…”

Oxidative capacity and hemolytic activity of settled dust from moisture‐damaged schools

“…1 The toxicity of PM is affected by the size, components, and emission source of the particles; thus, the hazard resulting from exposure is difficult to predict. 7,8 A recent study showed an increase in the immunotoxicological activity of dust from school buildings with higher microbial load, although not consistently associated with moisture-damage status of the building or symptoms of the occupants. 2 Immunotoxicological activity of indoor air PM has been studied most often with immunocytes [3][4][5][6] or lung epithelial cells.…”

“…2 Immunotoxicological activity of indoor air PM has been studied most often with immunocytes [3][4][5][6] or lung epithelial cells. 7,8 A recent study showed an increase in the immunotoxicological activity of dust from school buildings with higher microbial load, although not consistently associated with moisture-damage status of the building or symptoms of the occupants. 9 The failure to reliably identify moisture-damaged indoor environments with bioassays may indicate that the model system simply does not reflect the health responses of occupants accurately enough, but it could also be biased, for example, by other bioactive materials in the sample, the sampling method, or measured toxicological endpoints.…”