Bioaccessible heavy metals-sediment particles from Reconquista River induce lung inflammation in mice

Abstract

The Reconquista River (RR), one of the most polluted watercourses in Argentina, receives effluent discharges from heavily industrialized and highly populated settlements. During winter and summer, the floodplain remains dry, producing the oxidation of sulfide and organic matter present in the sediment, making heavy metals more bioaccessible. Dispersion of this sediment occurs, and thus harmful effects on the pulmonary health of residents and workers inhabiting the RR bank may take place. The authors characterized the sediment particles of the RR (RR-PM) morphologically by scanning electron microscopy and its elemental composition by energy dispersive X-ray spectroscopy (EDX) and Community Bureau of Reference (BCR) sequential extraction. Furthermore, the authors evaluated its biological impact on the respiratory system of BALB/c mice, generating four groups: control healthy, sensibilized with ovalbumin, exposed to particles, and sensibilized and exposed to particles. Sediment particles of the Reconquista River contained fine particulate matter, with a high concentration of bioaccessible Cu and Zn. The authors found that animal exposure to RR-PM caused polymorphonuclear cell lung infiltration, augmentation of O2(-), increase of proinflammatory cytokines (tumor necrosis factor alpha [TNFα], interleukin-6 [IL-6]) and apoptosis. This adverse response was more dramatic in the sensibilized and exposed to particles group. Even more, they proved the bioaccessible fraction present in the RR-PM to be responsible for these harmful effects. The authors conclude that RR-PM produces an adverse biological impact on the airways of healthy animals, which is largely aggravated in previously sensibilized animals.

Energy Dispersive X-ray (EDX) microanalysis: A powerful tool in biomedical research and diagnosis

“…studied the presence of bioaccessible heavy metalssediment particles from Reconquista River (RR-PM), one of the most polluted watercourses in Argentina. 29 The River receives effluent discharges from heavily industrialized and highly populated settlements. To this end, authors studied how this pollution induces lung inflammation in mice evaluating the biological impact of this particles on the respiratory system of BALB/c mice.…”

“…Moreover, they obtained that the sensibilized and exposed to particles groups had more dramatic adverse response. 29 …”

Pulmonary Inflammation and Cell Death in Mice After Acute Exposure to Air Particulate Matter From an Industrial Region of Buenos Aires

“…DCC was determined after cell fixation with methanol and staining with hematoxylin-eosin. At least 200 cells in each sample were counted by light microscopy (Ferraro et al 2012).…”

“…In this context, we recently analyzed the composition and biological impact of the PM from RR sediment (RR-PMs) on lung mice (Ferraro et al 2012). We showed that RR-PMs composition includes particles of heterogeneous sizes (agglomerates PM10 and PM2.5) with the presence, in its bioaccesible phase, of metals traces such as lead (Pb), cadmium (Cd), chromium (Cr) and sulfur (S) and that the cytotoxic and proinflammatory effects found in the respiratory tract are mostly determined by its metal content.…”

Geochemical characterization and the assessment of trace element retention in sediments of the Reconquista River, Argentina

“…Many authors have studied their toxicological impacts on the biota (Herkovits et al, 1996;Loez & Topalia ´n, 1999;Ossana et al, 2013Ossana et al, , 2016Rigacci et al, 2013). Of note, heavy metals retained in sediment particles (Cantera et al, 2018;Tufo et al, 2021) may eventually be released to water and generate adverse effects in exposed animals and humans (e.g., Ferraro et al, 2012).…”