Tag: Heavy metals

Reports

Distribution of arsenic species by seaweed parts, especially arsenic lipids

Published:

02/04/2024

Authors:

Rebecca Sim, Ásta H. Pétursdóttir, Natasa Desnica, Jörg Feldmann, Guðmundur Haraldsson, Karl Gunnarsson, Liberty O'Brien, Marta Weyer and Hildur I. Sveinsdóttir.

Supported by:

Icelandic Research Fund

Contact

Rebecca Sim

Ph.D. Student

rebecca@matis.is

Distribution of arsenic species within the macroalgae 
– an emphasis on arsenolipids

Algae are rich in minerals and desirable bioactive substances, but they can also absorb large amounts of trace elements, such as toxic heavy metals, including the element arsenic. Arsenic is found as inorganic arsenic in the sea and is taken up in that chemical form by the algae. In the algae, however, arsenic is detected not only as inorganic arsenic but as a wide range of arsenic compounds, so-called organic compounds of arsenic, for example arsenosaccharides and arsenolipids. There is still a lot of mystery about the origin of these compounds. In general, organic forms of arsenic have been considered quite harmless, unlike inorganic arsenic, which is a known carcinogen. However, recent studies on arsenolipids have shown that they can be as cytotoxic as inorganic arsenic. It is also believed that arsenosugar can possibly have long-term negative effects with regular consumption. Levels of arsenolipids are generally not high in algae, but the starting point of their production is thought to occur in algae. Algae are part of the regular food intake in the Eastern part of the world and are becoming increasingly popular in the West, so more information about these compounds is urgently needed to fully assess the risks associated with their consumption as well as to ensure that appropriate regulations are put in place regarding their maximum levels in foodstuffs. In order to understand the toxicological effects of algae consumption, it is extremely important that more data be collected on all the different chemical forms of arsenic, in particular on arsenolipids, but limited information is currently available on them. Samples of red, green and brown algae were collected near Grindavík and Kjalarnes, at two different points in time. The samples were thoroughly analyzed for heavy metals and arsenic analysis was carried out to better understand the chemical form in which the arsenic was present. Selected samples of brown, red and green algae were measured for species analysis of arsenolipids using mass spectrometry HPLC-ICP-M/ESI-MS/MS and HPLC-qToF-MS. In addition, brown macroalgae were divided into biological fractions to determine whether the distribution of arsenic species is uniform throughout the seaweed. Limited information exists globally on arsenolipids in seaweed, so this extensive profiling of them in different species of algae will help elucidate how these enigmatic organic compounds are formed and where they are stored. The data can also be used for risk assessment of arsenic species in seaweed for human consumption and can therefore influence future food safety legislation.
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In recent years seaweed has gained popularity as a health food due to its high content of minerals and vitamins. However, seaweeds may also accumulate high levels of potentially toxic elements – in particular arsenic, which may become incorporated into larger biological molecules such as sugars and lipids. It is unclear how these organic arsenic compounds are formed/stored and if they may serve a biological purpose (ie, detoxification or energy storage). However, toxicological studies into arsenic-containing lipids have demonstrated cytotoxicity comparable to that of arsenite, a known carcinogen, and arsenic-containing sugars are suspected to display toxicity with chronic exposure. This project aims to investigate variations in the distribution of arsenic compounds throughout several classes and species of seaweed. Samples of brown, red and green macroalgae were collected from two locations in Iceland across two different months and analyzed for several potentially toxic elements as well as hydrophilic arsenic speciation using HPLC-ICP-MS. Brown macroalgae were additionally sectioned into anatomical parts to determine if the distribution of arsenic species differs throughout the thallus. Select samples were chosen for state-of-the-art lipophilic arsenic speciation using HPLC-ICP-MS/ESI-MS/MS and HPLC-qToF-MS. Limited information is available on arsenic speciation in seaweed thus it is hoped that this extensive profiling of several different species will help elucidate how these unusual compounds are formed and stored. The data from this project will also contribute to the necessary information needed for the risk assessment of arsenic species in seaweed for human consumption and may have an impact on future food safety legislation.

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Reports

Results of continuous monitoring of undesirable substances in seafood from the resource 2018

Published:

26/02/2019

Authors:

Sophie Jensen, Natasa Desnica, Branka Borojevic, Svanhildur Hauksdóttir, Helga Gunnlaugsdóttir

Supported by:

Ministry of Industry and Innovation

Contact

Sophie Jensen

Project Manager

sophie.jensen@matis.is

Results of continuous monitoring of undesirable substances in seafood from the resource 2018

This report summarizes the results obtained in 2018 for the screening of various undesirable substances in the edible part of Icelandic marine catches.

The main aim of this project is to gather data and evaluate the status of Icelandic seafood products in terms of undesirable substances and to utilize the data to estimate the exposure of consumers to these substances from Icelandic seafood and risks related to public health. The surveillance program began in 2003 and was carried out for ten consecutive years before it was interrupted. The project was revived in March 2017 to fill in gaps of knowledge regarding the level of undesirable substances in economically important marine catches for Icelandic export. Due to financial limitations the surveillance now only covers screening for undesirable substances in the edible portion of marine catches for human consumption and not feed or feed components. The limited financial resources have also required the analysis of PAHs, PBDEs and PFCs to be excluded from the surveillance, providing somewhat more limited information than in 2013. However, it is considered a long-term project where extension and revision is constantly necessary.

In general, the results obtained in 2018 were in agreement with previous results on undesirable substances in the edible part of marine catches obtained in the monitoring years 2003 to 2012 and 2017.

In this report from the surveillance program, the maximum levels for dioxins, dioxin-like PCBs and non-dioxin-like PCBs in foodstuffs (Regulation No 1259/2011) were used to evaluate how Icelandic seafood products measure up to limits currently in effect.

The results show that with regard to the maximum levels set in the regulation, the edible parts of Icelandic seafood products contain negligible amounts of dioxins, dioxin like and non-dioxin-like PCBs. In fact, all samples of seafood analyzed in 2018 were below EC maximum levels.

Furthermore, the concentration of ICES6-PCBs was found to be low in the edible part of the marine catches, compared to the maximum limits set by the EU (Commission Regulation 1259/2011).

The results showed that the concentrations of heavy metals, eg cadmium (Cd), lead (Pb) and mercury (Hg) in the edible part of marine catches were always well below the maximum limits set by the EU.

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Reports

Results of continuous monitoring of undesirable substances in seafood from the resource 2017 / Undesirable substances in seafood - results from the Icelandic marine monitoring activities in the year 2017

Published:

17/01/2018

Authors:

Sophie Jensen, Natasa Desnica, Erna Óladóttir, Branka Borojevic, Helga Gunnlaugsdóttir

Supported by:

Atvinnuvega- og nýsköpunarráðuneytið / Ministry of Fisheries and Agriculture

Contact

Sophie Jensen

Project Manager

sophie.jensen@matis.is

Results of continuous monitoring of undesirable substances in seafood from the resource 2017 / Undesirable substances in seafood - results from the Icelandic marine monitoring activities in the year 2017

This report summarizes the results of monitoring of undesirable substances in edible parts of seafood in 2017. The monitoring began in 2003 with the help of the then Ministry of Fisheries, the current Ministry of Industry and Innovation, and Matís ohf. on the collection of data and the publication of reports for this systematic monitoring during the period 2003-2012. In recent years, there has been a lack of funds to continue work on this monitoring project, so this important data collection was suspended as well as the publication of results in the period 2013-2016. in edible parts of seafood from the resource intended for human consumption, but not fishmeal and fish oil for feed. For the same reason, no chemical analyzes were performed on PAH, PBDE and PFC substances this time. The aim of the project is to demonstrate the position of Icelandic seafood in terms of safety and health and to use the data in the risk assessment of food to ensure the interests of consumers and public health. The project builds a knowledge base on the amount of undesirable substances in economically important species and marine products, it is defined as a long-term project where monitoring and review is constantly necessary. In general, the results obtained in 2017 were in line with previous results from 2003 to 2012. The results showed that Icelandic seafood contains an insignificant amount of persistent organic pollutants such as dioxins, PCBs and pesticides. EU maximum levels for dioxins and dioxin-like PCBs (DL-PCBs) in food and feed were lowered on 1 January 2012 (EU Regulation No. 1259/2011) and maximum levels were set for "non-dioxin-like" PCBs (NDL-PCBs) for the first time ). The new maximum values are used in this report to assess how Icelandic seafood meets EU requirements. The results for 2017 show that despite the change in maximum levels for dioxins, DL-PCBs and NDL-PCBs, all samples of marine products for human consumption are below the EU maximum levels for persistent organic pollutants and heavy metals. The concentration of so-called ICES6-PCBs turned out to be low in the edible part of fish, compared to the new EU maximum values. The results also showed that the concentration of heavy metals, such as cadmium (Cd), lead (Pb) and mercury (Hg) in Icelandic seafood was always below the EU maximum values.

This report summarizes the results obtained in 2017 for the screening of various undesirable substances in the edible part of marine catches. The surveillance program began in 2003 and was carried out for ten consecutive years before it was interrupted. The project was revived in March 2017 to fill in gaps of knowledge regarding the level of undesirable substances in economically important marine catches for Icelandic export. Due to financial restrictions the surveillance now only covers screening for undesirable substances in the edible portion of marine catches for human consumption not feed or feed components. The limited financial resources also required that the analysis of PAHs, PBDEs and PFCs were excluded in the surveillance, and therefore this report provides somewhat more limited data than previously. However, it is considered to be a long-term project where extension and revision is constantly necessary. The main aim of this project is to gather data and evaluate the status of Icelandic seafood products in terms of undesirable substances and to utilize the data to estimate the exposure of consumers to these substances from Icelandic seafood and risks related to public health. Generally, the results obtained in 2017 are in agreement with previous results on undesirable substances in the edible part of marine catches obtained in the monitoring years 2003 to 2012. The results show that the edible parts of Icelandic seafood products contain negligible amounts of persistent organic pollutants (POPs) such as; dioxins, dioxin like PCBs and pesticides. As of January 1st 2012 Commission Regulation No 1259/2011, regarding maximum levels for dioxins, dioxin-like PCBs and non-dioxin-like PCBs in foodstuff came into force. This amendment to the existing regulation (No 1881/2006) resulted in changes in maximum levels for dioxins and dioxin-like PCBs for many food products due to changes in toxicological assessment of dioxins. Furthermore, maximum levels for non-dioxin-like PCBs have now been established in foodstuffs. In this report, we use these revised maximum levels for dioxins, dioxin-like PCBs and nondioxin-like PCBs in foodstuffs to evaluate how Icelandic seafood products measure up to limits currently in effect. The results obtained year 2017 reveal that all samples of seafood for human consumption were below EC maximum levels for POPs and heavy metals. Furthermore, the concentration of ICES6-PCBs was found to be low in the edible part of fish muscle, compared to the maximum limits set by the EU (Commission Regulation 1259/2011). The results showed that the concentrations of heavy metals, eg cadmium (Cd), lead (Pb) and mercury (Hg) in Icelandic seafood products was always well below the maximum limits set by EU.

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Reports

Undesirable substances in seafood products - results from the Icelandic marine monitoring activities in the year 2012

Published:

01/05/2013

Authors:

Sophie Jensen, Hrönn Ólína Jörundsdóttir, Natasa Desnica, Þuríður Ragnarsdóttir, Helga Gunnlaugsdóttir

Supported by:

Atvinnuvega‐ og nýsköpunarráðuneytið / Ministry of Industries and Innovation

Contact

Sophie Jensen

Project Manager

sophie.jensen@matis.is

Undesirable substances in seafood products - results from the Icelandic marine monitoring activities in the year 2012

This report summarizes the results of monitoring for undesirable substances in seafood, fishmeal and fish oil for feed since 2012. The EU maximum levels for dioxins and dioxin-like PCBs (DL-PCBs) in food and feed were recently lowered and maximum levels were set for the first time. set for "non-dioxin-like" PCBs (NDL-PCBs). The new maximum values are used in this report to assess how Icelandic seafood meets EU requirements. The monitoring began in 2003 with the help of the then Ministry of Fisheries, the current Ministry of Industry and Innovation, and has now been carried out for ten consecutive years. The project builds a knowledge base on the amount of undesirable substances in economically important species and marine products, it is defined as a long-term project where monitoring and review are constantly necessary. In 2012, emphasis was placed on gathering information on the organic compounds PFC and inorganic trace elements in edible seafood, but also in fishmeal and fish oil for feed. In general, the results obtained in 2012 were in line with previous results from 2003 to 2011. The results showed that Icelandic seafood contains insignificant amounts of persistent organic pollutants such as dioxins, PCBs, pesticides and PBDEs. This was the second year that PFCs have been detected in Icelandic seafood and perfluorooctane sulfon amide (PFOSA) was the only PFC substance that exceeded the detection limit, other PFC substances were not measured. The results from 2012 showed that despite the change in maximum levels for dioxins, DL-PCBs and NDL-PCBs (EU Regulation No. 1259/2011), all samples of seafood for human consumption are below the EU maximum levels for persistent organic pollutants and heavy metals. The concentration of reference PCBs (marker PCBs) turned out to be minimal in the edible part of the fish, compared to the new maximum EU values. The results also showed that the concentration of heavy metals, such as cadmium (Cd), lead (Pb) and mercury (Hg) in Icelandic seafood was always below the EU maximum values. In March 2012, EU Regulation No. 277/2012 entered into force, lowering maximum levels for dioxins and DL-PCBs in animal feed, but also setting maximum levels for NDL-PCBs. Despite this change, all samples of fishmeal and fish oil for feed were measured below maximum levels, with the exception of one blue whiting meal sample containing toxafen above EU maximum levels.

This report summarizes the results obtained in 2012 for the screening of various undesirable substances in the edible part of marine catches, fish meal and fish oil for feed. The newly established maximum levels for dioxins, dioxin ‐ like PCB and non dioxin ‐ like PCB in foodstuffs and animal feed are used to evaluate how Icelandic seafood products measure up to EC limits currently in effect. The surveillance program began in 2003 and has now been carried out for ten consecutive years. The project fills in gaps of knowledge regarding the level of undesirable substances in economically important marine catches for Icelandic export. It is considered to be a long ‐ term project where extension and revision are constantly necessary. In the year 2012 emphasis was placed on gathering information on the organic compounds PFCs and inorganic trace elements in the edible part of marine catches as well as in the fish meal and fish oil for feed. Generally, the results obtained in 2012 are in agreement with previous results from the years 2003 to 2011. The results show that the Icelandic seafood products contain negligible amounts of persistent organic pollutants (POPs) such as dioxins, dioxin like PCBs, pesticides and PBDEs. This is the second time PFCs are analyzed in Icelandic seafood and fish products and the results show that the main PFC compound, perfluorooctane sulfone amide (PFOSA) was the only congener detected. The results obtained in the year 2012 reveal that despite the recent change by the EC in maximum levels for dioxins, dioxin ‐ like PCB and non dioxin ‐ like PCB in foodstuffs, all samples of seafood for human consumption were below EC maximum levels for POPs and heavy metals. Furthermore, the concentration of marker PCBs was found to be low in the edible part of fish muscle, compared to the maximum limits set by the EU (Commission Regulation 1259/2011). The results showed that the concentrations of heavy metals, eg cadmium (Cd), lead (Pb) and mercury (Hg) in Icelandic seafood products was always well below the maximum limits set by EU. In March 2012 Commission Regulation No 277/2012, regarding maximum levels for dioxins and PCBs in animal feed came into effect and after the implementation of this regulation maximum levels are now also set for non dioxin ‐ like PCBs. Despite of this change all samples of fish meal and fish oil for feed measured were below the EC maximum limits for feed components of marine origin except for one blue whiting meal sample that exceeds the maximum limits for toxaphene.

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Reports

Gæðakræklingur er gulls ígildi / Icelandic blue mussels - A valuable high quality product

Published:

01/12/2011

Authors:

Natasa Desnica, Sophie Jensen, Guðrún G. Þórarinsdóttir, Jón Óskar Jónsson, Hörður G. Kristinsson, Helga Gunnlaugsdóttir

Supported by:

AVS

Contact

Natasa Desnica

Research Group Leader

natasa@matis.is

Gæðakræklingur er gulls ígildi / Icelandic blue mussels - A valuable high quality product

In order for Icelandic mussel farming to grow and prosper, it is important to carry out basic research into the safety and quality of fresh Icelandic mussels that can be used by producers in marketing and selling the products. The purpose of this eighteen-month research project was to collect information on the safety and quality of mussels (Mytilus edulis) in market size (> 45 mm) grown off the coast of Iceland. A total of thirteen market-sized mussel samples were collected at four different breeding sites inland (Hvalfjörður, Breiðafjörður, Álftafjörður and Eyjafjörður) at different times of the year. Market-sized mussels were not found in Eskifjörður and this breeding site was therefore excluded from the project. Instead, samples were taken more often at the other four breeding sites than originally planned. Mussels were collected from breeding lines and time and location recorded. Weight, height and body mass were measured. The mussel was sexed and the stage of puberty was estimated in each sample. In this project, significant information was collected on nutrient content (protein, water, fat, ash) as well as bioactive substances such as selenium, zinc, carotenoids and fatty acid compositions in mussels from different cultivation sites and at different seasons. Unwanted inorganic trace elements (lead, mercury, cadmium, copper, nickel, arsenic, chromium and silver) were also measured in all samples. Work was also done on setting up and testing rapid measurement methods for measuring three types of algae toxins, ie ASP, PSP and DSP. The measurement methods were optimized against the equipment available at Matís and also measured reference samples (ie mussels with a known amount of algae toxin) to assess the quality of the measurements. Two types of rapid tests available on the market were tested to assess their performance in algae toxicity measurements in mussels. On the one hand, so-called Jellet tests were tested and on the other hand ELISA tests. The result is that both tests are relatively simple to use, however, it is necessary to test them on slightly more samples than was done here, in order to make a better assessment of how best to use them in quality control of mussel farming. It is necessary to be aware of the limitations of these rapid tests as they will not completely replace measurements by approved research methods. These tests, on the other hand, could significantly reduce the number of samples sent for approved measurements, as no samples would be sent when the pre-tests show that algae toxins are present and no mussels were allowed to be harvested. The results indicate that Icelandic mussels have an optimal nutrient composition, which is subject to natural seasonal changes. Multivariate analysis (PCA) shows that mussels contain a higher percentage of fat and protein in the spring (May and June), probably because the mussel is preparing to spawn at this time of year. In early autumn, the protein content decreases while the amount of unknown substances increases. At this time of year, spawning is complete, if not complete. The analysis also shows a weak positive correlation between protein and fat, but a strong negative correlation between protein and unknown substances. The concentration of heavy metals (mercury, lead, cadmium) was generally low, but in some cases the concentration of cadmium was higher than permitted by Icelandic and European Union regulations (1 mg / kg). It is therefore important to monitor the concentration of cadmium in Icelandic mussels before they go on the market. The results of fatty acid analysis show that Icelandic mussels contain significant amounts of the omega-3 fatty acids EPA (C20: 5n3) and DHA (C22: 6n3) as well as Palmitoleate (C16: 1n7), all of which are known for their beneficial effects on health. The results of the project show that Icelandic mussels are competitive in terms of nutrient composition and also contain positive bioactive substances. These results will undoubtedly be useful to mussel farmers in marketing presentations and planning regarding the harvesting and sale of mussel products.

In order to enable the Icelandic blue mussel industry to grow, market and sell their product, there is a critical need to perform some fundamental studies. The purpose of this eighteen months long research project was to investigate the quality and value of Icelandic blue mussels (Mytilus edulis) grown at different growing sites of Iceland. A total of 13 samples were collected from blue mussel culture sites around Iceland (Hvalfjörður, Breiðifjörður, Álftafjörður and Eyjafjörður). The Eskifjördur sampling site was excluded from the project due to the lack of market sized blue mussels and resulted in sampling from growing lines of four different culture sites. The mussels were characterized according to location, time of year, weight, length, meat yield and reproductive status. This report summarizes the considerable amounts of data obtained regarding the chemical composition of Icelandic blue mussels, including trace metals (lead, cadmium, copper, zinc, mercury, arsenic, selenium, chrome, nickel and silver), nutrients (moisture, protein, lipid and ash content) and bioactive components (carotenoids and fatty acid profile). In addition, the presence of common algal toxins in blue mussels was investigated and concluded that further work will be needed to optimize the rapid assays tested for measuring algal toxins ie PSP and DSP toxins. The results obtained need to be further verified by using standard addition procedures or with certified reference material. It is important to keep in mind that these rapid tests for PSP and DSP only provide screening results. Further testing with reference analytical methods will be required to confirm the results from these rapid tests before the mussels are harvested and sold on market. The rapid tests are suitable for quality control and decision making regarding whether or not it is safe to harvest the mussel crop or if the mussels should be harvested later after purification in the ocean. The results obtained here indicate that Icelandic blue mussels compose well balanced nutritional and trace element levels. A moderate seasonal variation pattern was observed in all measured nutritional parameters. A principal component analysis (PCA) showed that mussels contained higher proportion of fat and protein during spring (May ‐ June). In the autumn the proportion of protein reduced while the proportion of other unknown substances increased. The PCA analysis also revealed a weak positive correlation between protein and fat and a strong negative correlation between protein and other unknown substances. Heavy metal concentrations were generally low. However, elevated levels of cadmium were measured in mussel samples from certain culture sites, which in some cases exceeded the maximum EU limits (1 mg / kg) for cadmium in bivalve molluscs. The fatty acid profile revealed significant levels of omega ‐ 3 polyunsaturated fatty acids such as Eicosapentaenoic (EPA, C20: 5n3) and Docosahexaenoic (DHA, C22: 6n3) as well as Palmitoleate (C16: 1n7), all recognized for their health beneficial effects . This fundamental information proves that Icelandic blue mussels is a market competitive product of high quality and will greatly aid in developing the Icelandic mussel industry and in making the best choices considering growing, harvesting, marketing and selling their products.

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