Analysis and Risk Assessment of Seaweed

Abstract

During the last decade, the interest on the use of seaweed as food or feed, which was before limited to certain European regional subpopulations, has experienced a significant increase in other regions of the EU. In fact, the growing awareness and interest on sustainable and alternative food sources, healthier lifestyles and changes on dietary patterns brought seaweed to the spotlight for the general worldwide cuisine. Due to their high biosorption and accumulation capacity, seaweed can be an important source of increased exposure to persistent and potential harmful elements, such as cadmium (Cd), lead (Pb), mercury (Hg) and inorganic arsenic (iAs), or even some micronutrients, particularly iodine (I), to which an antioxidant role as been described in seaweed. This concentration potential has raised the interest of several Food Authorities regarding the risk of increased exposure to these elements. Moreover, the European Commission requested the collection of monitoring data on their levels aiming to aid the performance of better risk assessments and potentially set maximum levels on the European Legislation. This work aimed to obtain levels of these elements in species of seaweed (Fucus vesiculosus, Fucus serratus, Fucus spiralis, Fucus evanescens, Saccharina latissima, ulva lactuca and Ccladophora sp.) cultivated and harvested in Denmark, following European Commission's request. Additionally, a collaboration between Denmark, Ireland, France and the Netherlands was initiated to review and collect all the data available on scientific papers regarding the levels of these contaminants in seaweed worldwide. The final result of this work would be the publication of a review article. This Fellowship also provided on‐the‐job training on the evaluation of applications of new biocides and participation in the science based advises given to the Danish Food and Veterinary Administration, Danish EPA, the Danish Medical Agency and ECHA.

Characterisation and chemometric evaluation of 17 elements in ten seaweed species from Greenland

“…From the four collected responses, the portion size of a seaweed salad ranged from 20 g to 50 g, with a median of 33 g. To assess the nutritional benefits and exposure to toxic elements, we calculated element concentrations found in a 33 g single-seaweed species salad, prepared from fresh seaweed ( Table 4 ). Our estimated serving size is comparable with Sá Monteiro and colleagues [ 13 ], who estimated an intake of 5 g freeze dried weight per week, which corresponds to about 30 g fresh seaweed at an estimated moisture content of 80% (based on moisture contents reported by Holdt and Kraan [ 8 ]).…”

Characterisation and chemometric evaluation of 17 elements in ten seaweed species from Greenland

“…From the four collected responses, the portion size of a seaweed salad ranged from 20 g to 50 g, with a median of 33 g. To assess the nutritional benefits and exposure to toxic elements, we calculated element concentrations found in a 33 g single-seaweed species salad, prepared from fresh seaweed (Table 4). Our estimated serving size is comparable with Sá Monteiro and colleagues [13], who estimated an intake of 5 g freeze dried weight per…”

“…Seaweeds have a highly variable nutritional composition [8,9] but are generally good sources of minerals and iodine [8,10]. However, in some cases they are also known to contain undesirably high concentrations of certain chemical elements, which have been identified as hazardous: As, Cd, Hg, I and Pb [11][12][13][14]. This is attributed to the accumulation of cations from the seawater through their association with biopolymers [15] or, in the case of iodine in some species, its function as an antioxidant [16,17].…”

Seaweeds

“…Sodium salt of alginate has wide application in food and pharmaceutical industry for making highly viscous solution because of its ability to chelate metal ions. It is also used in food industry as a natural source of dietary fiber for developing functional foods 24,28 .…”

“…However, accumulation and concentration of nutrients in seaweeds varies with species to species, genera, growing area and climatic condition. Seaweeds can accumulate heavy metals and toxic compounds and can pose a serious health risk upon ingestion 7,28 . Roleda 34 , et al observed the effect of temporal and spatial variations in phenolics and heavy metal contents of seaweeds.…”