journal article·2025-06-21Open access

Assessment of Essential Elements and Potentially Toxic Elements (PTEs) in Organic and Conventional Flaxseeds: Implications for Dietary Exposure and Food Safety

Rodrigo de Lima Brum, Katarzyna Siedzik, Samuel Alejandro-Vega, Soraya Paz-Montelongo, Ángel J. Gutiérrez-Fernández, Dailos González-Weller, Arturo Hardisson, Malgorzata Misniakiewicz, Ewa Pyrzyńska, Flavio Manoel Rodrigues da Silva Júnior, Carmen Rubio

Applied Sciences· Volume 15· Issue 13

Abstract

Flax (Linum usitatissimum L.) is valued for its fibers and nutrient-rich seeds, which are increasingly consumed for their health benefits. However, flaxseeds can also accumulate potentially toxic elements (PTEs), raising concerns about safety. This study quantified 11 essential elements (e.g., Ca, Fe, Mg, and Zn) and 9 PTEs (e.g., Al, Cd, Pb, and Ni) in commercial flaxseed samples using inductively coupled plasma–optical emission spectrometry. Two intake scenarios (15 g/day and 30 g/day) were analyzed to estimate dietary exposure, with health risks assessed through the target hazard quotient (THQ) and hazard index (HI). The results showed that organic flaxseeds had higher levels of certain elements (e.g., Cu, K, and Pb), while Al and Ni were more abundant in conventional samples. Cadmium levels in both remained below the EU regulatory limit. The highest estimated daily intakes were for K, Mg, and Ca, highlighting the seeds’ nutritional value. However, HI values suggested that Al and Pb could pose health risks. These findings emphasize flaxseeds’ dual nature as both beneficial and potentially harmful, particularly given the lack of specific regulatory limits and limited data on elemental composition. Continued monitoring and risk assessment are recommended to safeguard public health.
Source: crossref · Quality: baseline

Research context

OpenAlex topics: Heavy Metals in Plants · Aluminum toxicity and tolerance in plants and animals · Food composition and properties

SciVX discovery tags are terminology-based. OpenAlex topics are source-provided classifications.

Affiliations

Laboratório de Ensaios Farmacológicos e Toxicológicos, Universidade Federal do Rio Grande, Rio Grande 96203-900, RS, Brazil

Grupo de Investigación en Toxicología Ambiental y Seguridad de los Alimentos y Medicamentos, Universidad de La Laguna, 38071 La Laguna, Spain

Faculty of Health, WSB Merito University in Gdansk, Aleja Grunwaldzka 238A, 80-266 Gdańsk, Poland

Servicio de Inspección y Laboratorio del Área de Salud de Tenerife, Servicio Canario de Salud, Gobierno de Canaprias, 38006 Santa Cruz de Tenerife, Spain

Department of Food Product Quality, Krakow University of Economics (Katedra Jakości Produktów Żywnościowych, Uniwersytet Ekonomiczny w Krakowie), Rakowicka 27, 31-510 Kraków, Poland

Funding

Krakow University of Economics · Coordenacao de Aperfeicoamento de Pessoal de Nivel Superior (CAPES) (Brazil)

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