The wild plant Gnaphalium lavandulifolium as a sentinel for biomonitoring the effects of environmental heavy metals in the metropolitan area of México Valley

• Published in: Environmental monitoring and assessment Vol. 195; no. 1; p. 195
• Main Authors: Cortés-Eslava, Josefina, Gómez-Arroyo, Sandra, Cortés, Pablo Antonio Mérida, Jiménez-García, Luis Felipe, Lara-Martínez, Reyna, Arenas-Huertero, Francisco, Morton-Bermea, Ofelia, Testillano, Pilar S.
• Format: Journal Article
• Language: English
• Published: Cham Springer International Publishing 01.01.2023; Springer Nature B.V
• Subjects: Air pollution; Air pollution effects; Aluminum; Atmospheric Protection/Air Quality Control/Air Pollution; Biomonitoring; Cadmium; Caspase-3; Cell death; Cell walls; Chemical analysis; Chloroplasts; Chromatin; Chromium; Contamination; Controlled conditions; Copper; Cytoplasm; Earth and Environmental Science; Ecology; Ecosystems; Ecotoxicology; Environment; Environmental effects; Environmental Management; Environmental monitoring; Environmental science; Exposure; Gnaphalium; Heavy metals; Immunohistochemistry; Lead; Leaves; Light microscopy; Manganese; Metals; Metropolitan areas; Monitoring/Environmental Analysis; Optical microscopy; Plants; Pollutants; Pollution; Protoplasts; Sea level; Starch; Starch grains; Toxicity; Valleys; Zinc; Mexico; Bioindicators; Chloroplasts; Environmental stressors; Plant biomarkers
• ISSN: 0167-6369; 1573-2959
• DOI: 10.1007/s10661-022-10763-9

Biomonitoring is a valuable tool for assessing the presence and effects of air pollutants such as heavy metals (HM); due to their toxicity and stability, these compounds can affect human health and the balance of ecosystems. To assess its potential as a sentinel organism of HM pollution, the wild plant Gnaphalium lavandulifolium was exposed to four sites in the metropolitan area of México Valley (MAMV): Altzomoni (ALT) Coyoacán (COY), Ecatepec (ECA), and Tlalnepantla (TLA) during 2, 4, and 8 weeks, between October and November 2019. Control plants remained under controlled conditions. The chemical analysis determined twelve HM (Al, As, Cd, Co, Cr, Cu, Fe, Mn, Ni, Pb, V, and Zn) in the leaves. Macroscopic damage to the leaves, later determined in semi-thin sections under light microscopy, lead to a finer analysis. Transmission electron microscope (TEM) showed major structural changes: chromatin condensation, protoplast shrinkage, cytoplasm vacuolization, cell wall thinning, decreased number and size of starch grains, and plastoglobules in chloroplasts. All these characteristics of stress-induced programed cell death (sPCD) were related to the significant increase of toxic HM in the leaves of the exposed plants compared to the control ( p  < 0.05). Immunohistochemistry revealed a significant amount of proteases with caspase 3–like activity in ECA and TLA samples during long exposure times. Ultrastructural changes and sPCD features detected confirmed the usefulness of G. lavandulifolium as a good biomonitor of HM contamination. They supported the possibility of considering subcellular changes as markers of abiotic stress conditions in plants.