1.
Human nasal mucosal C-reactive protein responses after inhalation of ultrafine welding fume particles: positive correlation to systemic C-reactive protein responses.
Baumann, R, Brand, P, Chaker, A, Markert, A, Rack, I, Davatgarbenam, S, Joraslafsky, S, Gerhards, B, Kraus, T, Gube, M
Nanotoxicology. 2018;(10):1130-1147
Abstract
Exposures to occupationally relevant ultrafine, zinc- and copper-containing welding fumes cause inflammatory responses involving systemic IL-6, C-reactive protein (CRP) and serum amyloid A (SAA), all associated with elevated risk of cardiovascular events. We investigated whether the systemic response is preceded by nasal inflammatory reactions. Fifteen nonsmoking male subjects were exposed for 6 h under controlled conditions to zinc-/copper-containing welding fumes (at 2.5 mg/m3) or ambient air control in a randomized order. Nasal secretions were collected before and at 1, 3, 6, 10, and 29 h after exposure. Nasal levels of selected biomarkers were determined by electrochemiluminescent assays and related to their systemic levels. Nasal interferon-γ (IFN-γ) peaked significantly 1 h after start of exposure compared to baseline. Nasal CRP as well as SAA increased significantly at 10 and 29 h compared to baseline. Receiver operating characteristic (ROC) curve analysis for differentiating welding fume from control exposure was performed: The highest area under ROC curve (AUC) values were found for the CRP increases (10, 29 h versus 0 h): AUC = 0.83, and for IFN-γ increases (1 h versus 0 h): AUC = 0.92. Nasal and systemic changes of CRP at 29 h revealed a strong correlation (Spearman rank test: increases compared to baseline: r = 0.815, p = 0.0022; absolute levels: r = 0.9, p = 0.0002). In conclusion, short-term exposure to a zinc- and copper-containing welding fume causes significant increases of inflammatory mediators in nasal mucosal lining fluid. Therefore, measurement of nasal inflammatory mediators may provide a useful means for occupational surveillance of workers exposed to ultrafine metal fume particles.
2.
Ceramic water filters impregnated with silver nanoparticles as a point-of-use water-treatment intervention for HIV-positive individuals in Limpopo Province, South Africa: a pilot study of technological performance and human health benefits.
Abebe, LS, Smith, JA, Narkiewicz, S, Oyanedel-Craver, V, Conaway, M, Singo, A, Amidou, S, Mojapelo, P, Brant, J, Dillingham, R
Journal of water and health. 2014;(2):288-300
Abstract
Waterborne pathogens present a significant threat to people living with the human immunodeficiency virus (PLWH). This study presents a randomized, controlled trial that evaluates whether a household-level ceramic water filter (CWF) intervention can improve drinking water quality and decrease days of diarrhea in PLWH in rural South Africa. Seventy-four participants were randomized in an intervention group with CWFs and a control group without filters. Participants in the CWF arm received CWFs impregnated with silver nanoparticles and associated safe-storage containers. Water and stool samples were collected at baseline and 12 months. Diarrhea incidence was self-reported weekly for 12 months. The average diarrhea rate in the control group was 0.064 days/week compared to 0.015 days/week in the intervention group (p < 0.001, Mann-Whitney). Median reduction of total coliform bacteria was 100% at enrollment and final collection. CWFs are an acceptable technology that can significantly improve the quality of household water and decrease days of diarrhea for PLWH in rural South Africa.