Thai Journal of Toxicology

Development of a Seaweed Consumption Survey Tool for Dietary Exposure Assessment to Heavy Metals

Dolratee Janjang — 2026-01-05

Seaweed products are widely consumed due to their perceived health benefits. Nonetheless, they can serve as sources of toxic contaminants, particularly heavy metals such as lead and cadmium, which may accumulate from their aquatic environments. To accurately assess dietary exposure to these contaminants, it is essential to obtain detailed information on seaweed consumption patterns, including type and quantity consumed. However, existing data often lack such specificity, as prior studies did not differentiate between seaweed types, thereby complicating the classification of sources, particularly in distinguishing between freshwater and marine varieties. This study focused on the development and validation of a semi-quantitative food frequency questionnaire (SQ-FFQ) for evaluating seaweed consumption patterns. To fill the gap, the four steps were performed: (1) conducting a market survey (2) compiling a detailed list of seaweed types, seaweed-based products, and commonly consumed menus, (3) developing an online SQ-FFQ via google form, and (4) evaluating the tool’s content validity through expert review using the Index of Item-Objective Congruence (IOC), as well as assessing internal consistency reliability with Cronbach’s alpha coefficient (α-coefficient). The market survey identified 103 nori items, 5 zi-cai items, and 29 wakame items. Based on this, a total of 16 seaweed-based menu items were selected and incorporated into the questionnaire, comprising 10 nori-based menus, 1 zi-cai-based menu, and 5 wakame-based menus. The SQ-FFQ showed acceptable content validity (IOC = 0.6-1.0) and high reliability (α = 0.954), confirming its suitability for assessing seaweed consumption in dietary exposure to heavy metals.

In Silico Predictions of Pharmacokinetic, Toxicity, and Molecular Interactions of Fungal β-1, 3/1, 6-Glucans Oligosaccharides with Immune Cells Receptors

Waewravee Watcharaphalanon — 2026-01-05

Abstract

β-1, 3/1, 6-glucans are polysaccharides in fungi’s cell walls (yeast, mold, and mushrooms) known to promote an immune response. Recently, gamma irradiation has been used to cut β-glucan polysaccharides into oligosaccharides with improved solubility. However, their pharmacokinetic and toxicity profiles, and molecular interactions with immune cell receptors were unknown. This study aims to use in silico models to predict the absorption, distribution, metabolism, excretion, and toxicity (ADMET) and the interaction of fungal β-1, 3/1, 6-glucans oligosaccharides with neutrophil receptors, including Dectin-1 and TLR2. Molecular docking and analysis were performed by using UCSF Chimera, AutoDock Vina, Proteins.plus, and PyMol. In silico ADMET analysis was done by using the pkCSM web server. The result showed that both 1.6 and 0.9 kDa forms of 1, 3/1, 6 β-glucans oligosaccharides can bind with Dectin-1 and TLR2 better than the reference compounds. Their binding capacity with the whole molecule is better than with the known binding sites. The 1.6 kDa β-glucans bind to the macromolecules of TLR2 better than the 0.9 kDa ones. ADMET analyses suggest low absorption, very low blood–brain barrier permeability, no CYP2D6 metabolism, and no hepatotoxicity or genotoxicity. In conclusion, this study predicts that the fungal β-1, 3/1, 6-glucans oligosaccharides are low-toxic and are fecally excreted without metabolic transformation. Their binding to Dectin-1 and TLR2 receptors on neutrophils is stronger than that of reference compounds and is influenced by molecular weight. These findings suggest that they possess new binding sites to both receptors, warranting further studies.

Editorial team

Editorial team — 2026-01-05