Distribution of metals and metalloids in dried seaweeds and health risk to population in southeastern China

Unusual holopelagic Sargassum mass beaching in Northwest Africa: Morphotypes, chemical composition, and potential valorisation

The rapid proliferation of holopelagic Sargassum spp. in the tropical Atlantic Ocean presents environmental challenges and economic opportunities. In 2022, Senegal witnessed its first significant holopelagic Sargassum beaching event, triggering widespread concern and interest from civil society, industrial sectors, and government. This study represents the first analysis of stranded holopelagic Sargassum's morphotypes and chemical composition in Northwest Africa. We highlight the nature of Sargassum stranding, dominated by S. fluitans III, and describe a putative new morphotype. Compared to most of the studies in the tropical Atlantic, Senegalese Sargassum displayed lower arsenic concentrations (9-29 ppm), higher cadmium levels (9-15 ppm), and increased mercury content (0.47-0.57 ppm). In addition, Senegalese Sargassum showed higher levels of iron (237-1017 ppm) and phosphorus (1300-1772 ppm). The biochemical analysis revealed high total protein levels (15-40 % DW) in Senegalese samples, though further analysis is required to confirm this. Furthermore, variations in biochemical composition within various parts of the Sargassum thallus were observed. The low arsenic content makes the beached Senegalese Sargassum attractive for valorisation and sets it apart from holopelagic Sargassum from all other regions where it occurs. However, caution should be taken regarding the high concentrations of cadmium. Our study highlights promising applications in Senegal and neighbouring countries, particularly in animal feed and agriculture. Noteworthy is the notable palladium content (2 ppm), valuable phenolic compounds, and mannitol, which present additional opportunities for the chemical industry. Our interdisciplinary approach enhances the global scientific understanding of the Sargassum issue. With the anticipation of more frequent Sargassum beaching events and, more generally, for seaweed exploitation, we advocate for inter-governmental African organisations to establish standardised norms for their exploitation. We recommend that the Food and Agriculture Organization/World Health Organization consider incorporating more seaweed in the Codex Alimentarius to facilitate their uses particularly when states deal with algal blooms.

Evaluation of the Bioavailability of Iodine and Arsenic in Raw and Cooked Saccharina japonica Based on Simulated Digestion/Caco-2 Cell Model

Kelp is a traditional healthy food due to its high nutritional content; however, its relatively high contents of iodine and arsenic have raised concerns about its edible safety. This study explored the effects of different cooking treatments on the contents of iodine and arsenic in kelp, evaluated the bioaccessibility and bioavailability of iodine and arsenic in kelp using in vitro digestion, and compared the differences in the transport characteristics of iodine in kelp and KIO3 using a Caco-2 monolayer cell transport model. The results show that the content of target elements that reached systemic circulation could be reduced by cooking and gastrointestinal digestion. The highest reductions in iodine and arsenic were 94.4% and 74.7%, respectively, which were achieved by boiling for 10 min. The bioaccessibility and bioavailability of iodine and arsenic were significantly improved by a cooking treatment. However, the contents of iodine and arsenic decreased significantly, with the bioaccessibility of iodine reducing from 3188.2 μg/L to 317.0 μg/L and that of arsenic reducing from 32.5 μg/L to 18.1 μg/L in the gastric phase after boiling. The findings also show that the efficiency of iodine transport in kelp and KIO3 was positively correlated with the transport time and negatively correlated with the concentration of iodine. With the increase in the iodine concentration, the rate of iodine transport in kelp decreased from 63.93% to 3.14%, but that of KIO3 was stable at around 35%, which indicates that the absorption efficiency of iodine from kelp was limited, even when too much kelp was ingested. In conclusion, the edible safety of kelp is significantly improved after cooking. The risk of excessive iodine and arsenic intake caused by consuming kelp is extremely low, and as an effective iodine supplement source, kelp has higher edible safety compared with KIO3. This study clarifies the safety of algae based on iodine and arsenic contents and also provides a basis for the formulation of food safety standards.

The paleoredox context of early eukaryotic evolution: insights from the Tonian Mackenzie Mountains Supergroup, Canada

Tonian (ca. 1000-720 Ma) marine environments are hypothesised to have experienced major redox changes coinciding with the evolution and diversification of multicellular eukaryotes. In particular, the earliest Tonian stratigraphic record features the colonisation of benthic habitats by multicellular macroscopic algae, which would have been powerful ecosystem engineers that contributed to the oxygenation of the oceans and the reorganisation of biogeochemical cycles. However, the paleoredox context of this expansion of macroalgal habitats in Tonian nearshore marine environments remains uncertain due to limited well-preserved fossils and stratigraphy. As such, the interdependent relationship between early complex life and ocean redox state is unclear. An assemblage of macrofossils including the chlorophyte macroalga Archaeochaeta guncho was recently discovered in the lower Mackenzie Mountains Supergroup in Yukon (Canada), which archives marine sedimentation from ca. 950-775 Ma, permitting investigation into environmental evolution coincident with eukaryotic ecosystem evolution and expansion. Here we present multi-proxy geochemical data from the lower Mackenzie Mountains Supergroup to constrain the paleoredox environment within which these large benthic macroalgae thrived. Two transects show evidence for basin-wide anoxic (ferruginous) oceanic conditions (i.e., high FeHR/FeT, low Fepy/FeHR), with muted redox-sensitive trace metal enrichments and possible seasonal variability. However, the weathering of sulfide minerals in the studied samples may obscure geochemical signatures of euxinic conditions. These results suggest that macroalgae colonized shallow environments in an ocean that remained dominantly anoxic with limited evidence for oxygenation until ca. 850 Ma. Collectively, these geochemical results provide novel insights into the environmental conditions surrounding the evolution and expansion of benthic macroalgae and the eventual dominance of oxygenated oceanic conditions required for the later emergence of animals.

Determination of the Nutrient and Toxic Element Content of Wild-Collected and Cultivated Seaweeds from Hawai'i

For centuries, Hawaiians have gathered seaweed for food, medicine, and ceremonial purposes. Seaweed contains nutrients, but some varieties can accumulate toxic elements. We measured target macrominerals (Na, Mg, P, K, Ca), microminerals (B, V, Mn, Co, Cu, Zn, Mo), and nonessential/toxic elements (As, Sr, Cd, Sn, Hg, Pb, and U) in a sample of wild-collected and cultivated seaweeds from Hawai'i. The samples consisted of brown (Sargassum aquifolium, Sargassum echinocarpum), red (Gracilaria parvispora, Halymenia formosa, Halymenia hawaiiana), and green (Ulva ohnoi) seaweed. Elemental composition was determined by inductively coupled plasma (ICP)-atomic emission spectroscopy and ICP-mass spectrometry (MS). Speciation of As was conducted by using liquid chromatography-ICP-MS. S. echinocarpum per 80 g serving was high in Ca (~37% daily value [DV]), U. ohnoi was high in Mg (~40%DV), H. formosa was high in Fe (~40%DV), and G. parvispora was high in Mn (~128%DV). In this study, the highest amounts of toxic elements were observed in S. aquifolium and S. echinocarpum (27.6 mg inorganic As/kg fdw), G. parvispora (43.3 mg Pb/kg fdw) and H. formosa (46.6 mg Pb/kg fdw). These results indicate that although seaweeds from Hawai'i contain a variety of nutrients, some species can accumulate high amounts of toxic elements.

Microplastic contamination in commercially packaged edible seaweeds and exposure of the ethnic minority and local population in Mexico

Diet is an important pathway for microplastic exposure. This study examined distinct edible seaweed products sold at ethnic food stores in Mexico for microplastic contamination, as well as the exposure of the Asian ethnic minority and local population to microplastics. Microplastics were extracted from seaweed samples using a wet oxide digestion with hydrogen peroxide followed by zinc chloride density separation. They were subsequently detected, quantified, and the polymer type was determined via microscopic inspection and Fourier transform infrared spectroscopy. Microplastic contamination was detected in all samples, with an average abundance of 24.0 ± 9.4 items g-1. Fibrous-shaped (61 %) and non-colored (57 %) microplastics were prevalent. Microplastics with sizes smaller than 0.2 mm prevailed (60 %), and they have the potential to penetrate gut barriers and endanger human health. Polymers identified consisted of polyethylene-polypropylene, polyamide, cellophane, rayon, and polyethylene terephthalate. According to pollution load index values, seaweed samples were minimally contaminated with microplastics, with values ranging between 3.7 and 6.0. The estimated yearly intake of microplastic from seaweed consumption by the South Korean and Chinese populations in Mexico was 5.8 × 104 ± 2.3 × 104 and 5.7 × 104 ± 4.9 × 104, respectively. This study's findings highlight the importance of improved control measures for minimizing microplastics in foods for export.

Potential Application of Marine Algae and Their Bioactive Metabolites in Brain Disease Treatment: Pharmacognosy and Pharmacology Insights for Therapeutic Advances

Seaweeds, also known as edible marine algae, are an abundant source of phytosterols, carotenoids, and polysaccharides, among other bioactive substances. Studies conducted in the past few decades have demonstrated that substances derived from seaweed may be able to pass through the blood-brain barrier and act as neuroprotectants. According to preliminary clinical research, seaweed may also help prevent or lessen the symptoms of cerebrovascular illnesses by reducing mental fatigue, preventing endothelial damage to the vascular wall of brain vessels, and regulating internal pressure. They have the ability to control neurotransmitter levels, lessen neuroinflammation, lessen oxidative stress, and prevent the development of amyloid plaques. This review aims to understand the application potential of marine algae and their influence on brain development, highlighting the nutritional value of this "superfood" and providing current knowledge on the molecular mechanisms in the brain associated with their dietary introduction.

Nickel in foodstuffs available on the Luxembourgish market and dietary intake

Nickel is a food contaminant of natural or anthropogenic origin. Monitoring of contaminants in food in general allows obtaining an overview on the presence of substances that are undesirable to health. The aim of this study was to analyse nickel content in food of non-animal origin and beverages sold in Luxembourg to determine the exposure of the population to this contaminant. In total, 660 samples were analysed in the timeframe from 2017 to 2021. The results demonstrate high concentrations of nickel in cashew nuts, walnuts, hemp and sunflower seeds, dried peas, oregano, and cocoa powder. Surveillance of contaminants in food allows identifying contributors to the chronic and acute exposure of nickel in order to potentially set official maximum levels in European legislation in the future, allowing for better enforcement actions in case of contaminated products and increasing consumer protection.

The Neuropharmacological Evaluation of Seaweed: A Potential Therapeutic Source

The most common neurodegenerative diseases (NDDs), such as Alzheimer's disease (AD) and Parkinson's disease (PD), are the seventh leading cause of mortality and morbidity in developed countries. Clinical observations of NDD patients are characterized by a progressive loss of neurons in the brain along with memory decline. The common pathological hallmarks of NDDs include oxidative stress, the dysregulation of calcium, protein aggregation, a defective protein clearance system, mitochondrial dysfunction, neuroinflammation, neuronal apoptosis, and damage to cholinergic neurons. Therefore, managing this pathology requires screening drugs with different pathological targets, and suitable drugs for slowing the progression or prevention of NDDs remain to be discovered. Among the pharmacological strategies used to manage NDDs, natural drugs represent a promising therapeutic strategy. This review discusses the neuroprotective potential of seaweed and its bioactive compounds, and safety issues, which may provide several beneficial insights that warrant further investigation.

Toxic Elements in Beans from Zhejiang, Southeast China: Distribution and Probabilistic Health Risk Assessment

This study described the distribution of As, Cd, Cr, Hg, and Pb in 692 bean samples from Zhejiang province, southeast China, and estimated the health risk using Monte Carlo simulation. The average levels of As, Cd, Cr, Hg, and Pb were 0.0349, 0.0379, 0.246, 0.0019, and 0.0246 mg kg-1. Correlation analyses showed very strong positive correlations for Cd-Pb in kidney beans and mung beans, Cd-As in black beans, and Pb-As in red beans. The target hazard quotients (THQs) were adopted for non-carcinogenic risk assessment, and THQs at the 50th percentile were all less than 1, indicating that there are no deleterious effects from rice exposure to these elements. When evaluating THQ for multiple elements, the certainty with a hazard index (HI) greater than 1 for children was 12.64%, for teens 11.54%, and for adults 1.01%. The sensitivity analysis reveals that the concentration of Cd in beans and ED (exposure duration) are the main principal factors that contributed to the total risk. The mean carcinogenic risks for children, teens, and adults were all less than 1 × 10-4, indicating no potential carcinogenic risk. Despite that, the routine monitoring of these elements, especially for Cd should be continued.

Metal and metalloid bioaccumulation in dried red seaweed Hypnea musciformis and health risk assessment for consumers

This study measured 22 metal and metalloid concentrations in Hypnea musciformis from the Bakkhali River estuary and Saint Martin's Island, Bangladesh and determined their potential impact on consumption. Student t-tests showed a significant variation in metal concentrations between the two sampling sites (p < 0.05). Mean concentrations of Co (2.49 ± 0.05 mg/kg), Fe (793.29 ± 11.76 mg/kg), Mn (368.72 ± 4.87 mg/kg), Pb (3.82 ± 0.02 mg/kg), V (11.23 ± 0.20 mg/kg) and Zn (16.60 ± 0.28 mg/kg) were higher in samples collected from the Bakkhali River estuary compared to Saint Martin's Island, while mean concentrations of Ca (484.18 ± 4.68 mg/kg), Cd (2.44 ± 0.03 mg/kg), Mg (2112.70 ± 17.80 mg/kg), Mo (1.57 ± 0.06 mg/kg), Sr (2377.57 ± 29.98 mg/kg), and Ti (258.27 ± 4.62 mg/kg) were higher in samples collected from Saint Martin's Island. Eight heavy metals (Pb, Cd, Zn, Cu, Ni, Mn, Cr, Fe) were used to assess potential health risks for adults, but no potential health risk was detected (HQ value>1). This study reveals positive Se-HBV for H. musciformis collected from both sampling sites, indicating no potential risks involved with Hg toxicity.

Evaluation of sediment dredging in remediating toxic metal contamination - a systematic review

Toxic metal pollution is a leading environmental concern for aquatic systems globally, and remedial dredging has been widely employed to mitigate its harmful impacts. In terms of the short-term impacts of remedial dredging, mixed results are reported in several studies. Despite its immediate negative impacts including saturation of water with toxic metals, increased turbidity, and sediment resuspension, positive impacts can be recorded over a stabilization period of 6-24 months after dredging. Nevertheless, the sustainability of these recorded positive effects cannot be ascertained as some studies have reported long-term regression in remediated sites' conditions. Evaluation of success determinants, site-measure compatibility, and determination of supplementary measures are keys to achieving and sustaining the projected benefits of remedial dredging and justifying its overall cost. This multicomponent study reviewed published literatures that documented the outcomes of short- and long-term dredging projects in toxic metal-polluted systems globally with a broad goal of examining how sediment removal impacts toxic metal dynamics in the aquatic system and understanding why the sustenance of positive impacts is controversial. In the meantime, this study also explored the preventative and remedial management strategies for attaining and sustaining positive dredging outcomes. The purpose of this study is to provide key recommendations for decision-making and policy development in aquatic toxic metal remediation.

Dietary exposure and risk assessment to trace elements and iodine in seaweeds

INTRODUCTION

Seaweeds are a rich source of elements such as iodine, and are also able to accumulate contaminants such as trace elements.

METHODS

The aim of this study was to assess the dietary exposure as well as the risk from iodine and trace elements in edible seaweeds for the French population using current consumption data. The contribution of seaweeds to overall dietary exposure to trace elements and iodine was evaluated, and for those substances with minimal contribution to overall dietary exposure, simulations were performed to propose increased maximal limits in seaweeds.

RESULTS

Cadmium, inorganic arsenic and mercury in seaweeds were very low contributors to total dietary exposure to these contaminants (0.7 % 1.1 % and 0.1 % on average, respectively). Dietary exposure to lead via seaweed may contribute up to 3.1 % of total dietary exposure. Dietary consumption of iodine via seaweed may contribute up to 33 % of total exposure to iodine, which makes seaweeds the strongest contributor to iodine in diet.

DISCUSSION

New maximal values in seaweeds are proposed for the very low contributors to total dietary exposure: 1 mg/kg dw for cadmium, 10 mg/kg dw for inorganic arsenic and 0.3 mg/kg dw for mercury.

Brown algae and their multiple applications as functional ingredient in food production

Brown algae are considered one of the resources that can contribute to transforming our global food system by promoting healthier diets and reducing environmental impact. In this sense, this review article aims to provide up-to-date information on the nutritional and functional improvement of brown algae when they are applied to different food matrices. Brown algae present sulfated polysaccharides (alginates, fucoidans, and laminarins), proteins, minerals, vitamins, dietary fibers, fatty acids, pigments, and bioactive compounds that can positively contribute to the development of highly nutritious food products, as well as used reformulate products already existing, to remove, reduce, increase, add and/or replace different components and obtain products that confer health-promoting properties. This review demonstrates that there is a tendency to use seaweed for the production of functional foods and that the number of commercially produced products from seaweed is increasing, that is, seaweed is a sector whose global market is expanding.

Current application of seaweed waste for composting and biochar: A review

To address the origins of ocean acidification, seaweed aquaculture is emerging as a key biosequestration strategy. Nevertheless, seaweed biomass is involved in developing food and animal feed, whereas seaweed waste from commercial hydrocolloid extraction is dumped in landfills, which together limit the carbon cycle and carbon sequestration. This work sought to evaluate the production, properties, and applications of seaweed compost and biochar to strengthen the "carbon sink" implications of aquaculture sectors. Due to their unique characteristics, the production of seaweed-derived biochar and compost, as well as their existing applications, are distinct when compared to terrestrial biomass. This paper outlines the benefits of composting and biochar production as well as proposes ideas and perspectives to overcome technical shortcomings. If properly synchronized, progression in the aquaculture sector, composting, and biochar production, potentially promote various Sustainable Development Goals.

Bioaccumulation level of metals and health risk assessment of selected red and green seaweeds validated by ICP-MS

The bioaccumulation of trace metals in 10 selected edible seaweeds was studied using inductively coupled plasma mass spectroscopy (ICP-MS). Bioaccumulation of higher levels of manganese (4.94 ± 0.15 μg/g) and aluminium (4.21 ± 0.18 μg/g) and lower levels of arsenic (0.18 ± 0.02 μg/g) and vanadium (0.09 ± 0.02 μg/g) were observed in Chlorophyta. In Rhodophyta, bioaccumulation of iron (8.51 ± 0.19 μg/g) was high, while lower levels of magnesium (0.13 ± 0.02 μg/g) and strontium (0.21 ± 0.01 μg/g) were observed among the seaweeds studied. Health assessment studies were also conducted on seaweeds to understand their effects on human consumption. The findings imply that consuming macroalgae has no health risk due to these elements in the general population. Furthermore, the confirmative toxicity of specific metals, such as Cd, Pb, and Zn metals in macroalgae, should be monitored constantly.

Assessment of trace metal bioaccumulation on the shells of edible gastropod Chicoreus ramosus and Hemifusus pugilinus

The current study aimed to examine how some gastropods absorbed trace metals (Chicoreus ramosus and Hemifusus pugilinus). The existence of 17 elements, including aluminium, arsenic, boron, calcium, cadmium, cobalt, chromium, copper, iron, potassium, lithium, manganese, sodium, nickel, phosphorus, lead, and zinc (Al, As, B, Ca, Cd, Co, Cr, Cu, Fe, K, Li, Mn, Na, Ni, P, Pb, and Zn), was confirmed by inductively coupled plasma-mass spectroscopy (ICP-MS) analysis of trace metals. According to the ICP-MS results, C. ramosus (Al: 1.97 ± 0.2 µg/g, Fe: 1.93 ± 0.2 µg/g, and As: 1.52 ± 0.4 µg/g) and H. pugilinus (Al: 1.85 ± 0.7 µg/g, Fe: 1.68 ± 0.6 µg/g, and As: 1.37 ± 0.6 µg/g) both had significant amounts of aluminium, iron, and arsenic, respectively. Zinc concentrations of 0.58 to 0.7 μg/g (C. ramosus) and 0.67 to 0.2 μg/g were recorded (H. pugilinus). The elemental composition of the surface of the sample was confirmed by scanning electron microscopy-energy-dispersive X-ray spectroscopy (SEM-EDX) micrographs, which also showed the degree of trace metal absorption in the chosen gastropod species.

Distribution of Cadmium in Fresh Vegetables Marketed in Southeast China and Its Dietary Exposure Assessment

This study investigated concentrations of cadmium (Cd) in 2465 vegetable samples (52 species) from 2018 to 2022 and estimated the associated health risk for local consumers. The average concentration of Cd was 0.035 mg kg−1, and the percentage of samples exceeding the Chinese maximum allowed concentration was 3.89% (96/2465). The top five species with highest Cd levels were Lilium brownii F (0.182 mg kg−1), Allium chinense G (0.117 mg kg−1), Allium macrostemon Bunge (0.105 mg kg−1), Colocasia esculenta (0.064 mg kg−1), and Amaranthus tricolor L (0.054 mg kg−1). Bulb vegetables had a higher relative accumulation of Cd compared to other vegetables. The levels of Cd in vegetables varied significantly across sampling areas and years. The mean estimated daily intake (EDI) of cadmium through consumption of vegetables was 0.519 μg kg−1 bw per day for adults and 0.217 μg kg−1 bw per day for children. The target hazard quotients (THQs) were all less than the threshold of 1 for both adults and children. This indicates that there is low health risk for Cd through vegetable consumption. However, routine monitoring of Cd levels in food is still crucial to ensure food safety and protect public health.

Dietary exposure to heavy metals and iodine intake via consumption of seaweeds and halophytes in the European population

EFSA assessed the relevance of seaweed and halophyte consumption to the dietary exposure to heavy metals (arsenic, cadmium, lead and mercury) and the iodine intake in the European population. Based on sampling years 2011-2021, there were 2,093 analytical data available on cadmium, 1,988 on lead, 1,934 on total arsenic, 920 on inorganic arsenic (iAs), 1,499 on total mercury and 1,002 on iodine. A total of 697 eating occasions on halophytes, seaweeds and seaweed-related products were identified in the EFSA Comprehensive European Food Consumption Database (468 subjects, 19 European countries). From seaweed consumption, exposure estimates for cadmium in adult 'consumers only' are within the range of previous exposure estimates considering the whole diet, while for iAs and lead the exposure estimates represent between 10% and 30% of previous exposures from the whole diet for the adult population. Seaweeds were also identified as important sources of total arsenic that mainly refers, with some exceptions, to organic arsenic. As regards iodine, from seaweed consumption, mean intakes above 20 μg/kg body weight per day were identified among 'consumers only' of Kombu and Laver algae. The impact of a future increase in seaweed consumption ('per capita') on the dietary exposure to heavy metals and on iodine intake will strongly depend on the seaweeds consumed. The exposure estimates of heavy metals and iodine intakes in 'consumers only' of seaweeds were similar to those estimated in a replacement scenario with selected seaweed-based foods in the whole population. These results underline the relevance of the current consumption of seaweeds in the overall exposure to different heavy metals and in the intake of iodine. Recommendations are provided for further work needed on different areas to better understand the relationship between seaweed consumption and exposure to heavy metals and iodine intake.

Enzymatic preparation and potential applications of agar oligosaccharides: a review

Oligosaccharides derived from agar, that is, agarooligosaccharides and neoagarooligosaccharides, have demonstrated various kinds of bioactivities which have been utilized in a variety of fields. Enzymatic hydrolysis is a feasible approach that principally allows for obtaining specific agar oligosaccharides in a sustainable way at an industrial scale. This review summarizes recent technologies employed to improve the properties of agarase. Additionally, the relationship between the degree of polymerization, bioactivities, and potential applications of agar-derived oligosaccharides for pharmaceutical, food, cosmetic, and agricultural industries are discussed. Engineered agarase exhibited general improvement of enzymatic performance, which is mostly achieved by truncation. Rational and semi-rational design assisted by computational methods present the latest strategy for agarase improvement with greatest potential to satisfy future industrial needs. Agarase immobilized on magnetic Fe3O4 nanoparticles via covalent bond formation showed characteristics well suited for industry. Additionally, albeit with the relationship between the degree of polymerization and versatile bioactivities like anti-oxidants, anti-inflammatory, anti-microbial agents, prebiotics and in skin care of agar-derived oligosaccharides are discussed here, further researches are still needed to unravel the complicated relationship between bioactivity and structure of the different oligosaccharides.

Iodine Bioavailability and Accumulation of Arsenic and Cadmium in Rats Fed Sugar Kelp (Saccharina latissima)

Suboptimal iodine status is a prominent public health issue in several European coun-tries. Brown algae have a high iodine content that, upon intake, may exceed the recommended dietary intake level, but iodine bioavailability has been reported to be lower than from potassium iodide (KI) and highly depends on algae species. Further, potential negative effects from other components in algae, such as cadmium (Cd) and arsenic (As), have also been addressed. In this study, we observed a lower bioavailability of iodine from farmed sugar kelp (Saccharina latissima) than from KI in female Wistar IGS rats. Urinary iodine excretion was 94-95% in rats fed KI and 73-81% in rats fed sugar kelp, followed by increased faecal iodine levels in rats fed sugar kelp. No effects on body weight, feed efficiency, or plasma markers for liver or kidney damage were detected. The highest dose of iodine reduced plasma free thyroxine (fT4) and total T4 levels, but no significant effects on circulating levels of thyroid-stimulating hormone (TSH) and free triiodo-thyronine (fT3) were detected. Faeces and urine measurements indicate that 60-80% of total As and 93% of Cd ingested were excreted in rats fed 0.5 and 5% kelp. Liver metabolomic profiling demonstrates that a high inclusion of sugar kelp in the diet for 13 weeks of feeding modulates metabolites with potential antioxidant activity and phytosterols.

Probabilistic chronic dietary exposure assessment adjusted for bioaccessible fraction to metals by consumption of seaweed and derived foods

The chronic exposure to heavy elements, i.e. Ni, As, Cd, Hg and Pb the evaluation of toxicological risk through intake of raw or seaweed based foods for Belgian consumers is presented in this study. The bioaccessible fraction, obtained for different metals, were used to refine the exposure values to avoid overestimation in the reported exposures. The decrease in the exposure values was higher for As with average bioaccessible fraction of 56.8% followed by Pb, Cd, Ni and Hg. The pure seaweeds show more approximation or exceeding of toxicological limits compared to the composite foodstuffs. For all elements (except Hg), toxicological limits are approached at the maximum exposure situation due to consumption of certain seaweed-based foods. Further, the study demonstrates that the introduction of innovative foods on an emerging market may result in potential health issues due to the shift in consumption patterns as the increased consumption of seaweed and their derivatives in Europe.

Freshwater Macroalgae, Oedogonium, Grown in Wastewater Reduce Diet-Induced Metabolic Syndrome in Rats

Macroalgae produce compounds with industrial, pharmaceutical and nutritional applications. In this study, biomass from the freshwater macroalgal genus Oedogonium was grown in either treated municipal wastewater (M) or ash dam water from a coal-fired power station (D). The biomass was investigated for its metabolic responses in high-carbohydrate, high-fat diet-fed rats, a model of human metabolic syndrome. The Oedogonium biomass cultured in M contained higher amounts of K, Mg, omega-3 polyunsaturated fatty acids (PUFA), insoluble fibre and β-carotene, while biomass grown in D contained higher amounts of Al, Fe, V, Zn, Mn and As. Biomass from M further increased body weight and inflammation in the heart and colon in high-carbohydrate, high-fat diet-fed rats. In contrast, biomass from D prevented changes in metabolic, cardiovascular and liver parameters without changing tissue histology. We suggest that increased intake of metals and metalloids through macroalgal biomass from D may decrease abdominal fat deposition while polysaccharides, PUFA and carotenoids from M may improve blood glucose responses in an obesogenic diet. Thus, macroalgal biomass grown in different wastewater sources could be acceptable for feed or food applications. This biomass could even provide potential health benefits in diet-induced metabolic syndrome.

Trace element bioaccumulation in edible red seaweeds (Rhodophyta): A risk assessment for consumers

As a precursor to risk assessment and risk management through consuming contaminated seafood, food safety needs to be quantified and assured. Seaweed is an increasing dietary component, especially in developing countries, but there are few studies assessing uptake rates of contaminants from this route. As such, the present study determined likely human uptake due to the trace elemental (Fe, Mn, Ni, Cu, Zn, Se, Hg, and As) concentrations in the edible red seaweeds (Rhodophyta) Gelidium pusillum and Hypnea musciformis, growing in the industrialised Cox's Bazar coastal area of Bangladesh. Metal and metalloid concentrations in G. pusillum were in the order (mg/kg): Fe (797 ± 67) > Mn (69 ± 4) > Ni (12 ± 5) > Zn (9 ± 4) > Cu (9 ± 4) >Se (0.1 ± 0.1) > Hg (0.1 ± 0.01), and in H. musciformis: Fe (668 ± 58) > Mn (28 ± 5) > Ni (14 ± 2) > Zn (11 ± 5) > Cu (6 ± 4) >Se (0.2 ± 0.03) > Hg (0.04 ± 0.01). Despite the industrial activities in the area, and based on 10 g. day^-1 seaweed consumption, it is concluded that these concentrations pose no risk to human health as part of a normal diet according to the targeted hazard quotient and hazard index (THQ and HI) (values < 1). In addition, and as a novel aspect for seaweeds, Selenium Health Benefit Values (Se-HBV) were determined and found to have positive values. Seaweed can be used as an absorber of inorganic metals for removing contamination in coastal waters. The results are a precursor to further research regarding the efficiency and rate at which seaweeds can sequester metal contamination in water. In addition, management techniques need to be developed thereby to control the contaminant inputs.

Heavy metals and metalloids in edible seaweeds of Saint Martin's Island, Bay of Bengal, and their potential health risks

The present study aimed to assess the levels of heavy metals and metalloids present in six seaweeds and their potential impact on consumption. The highest concentration of 11 metals, i.e., Be (0.47 mg/kg), Co (4.34 mg/kg), Cr (23.46 mg/kg), Cu (11.96 mg/kg), Fe (2290.26 mg/kg), Li (11.55 mg/kg), Ni (13.75 mg/kg), Pb (6.67 mg/kg), Ti (736.62 mg/kg), Tl (0.14 mg/kg), and V (33.09 mg/kg) were observed in Enteromorpha intestinalis (green seaweeds). Besides, the highest concentration of Ca (1071.09 mg/kg), Cd (5.81 mg/kg), Mn (1003.41 mg/kg), Sr (2838.86 mg/kg), and Zn (41.95 mg/kg) were found in Padina tetrastromatica (brown seaweeds). Eight metals (Pb, Cd, Zn, Cu, Ni, Mn, Cr, Fe) have been used to assess the potential health risk for adults, but no potential health risk was detected (HQ value > 1). The HI value of E. intestinalis and P. tetrastromatica were >1, implying that these two seaweeds are not safe for human consumption as there is a carcinogenic health risk for adults.

Probabilistic determination of a maximum acceptable level of contaminant to reduce the risk of overexposure for a novel or emerging food: the case of cadmium in edible seaweed in the French population

European and French populations are overexposed to cadmium (Cd) through their foods. The risk of increased cadmium exposure for consumers needs to be limited by reduced maximum limits (ML) for novel foodstuffs such as edible seaweed in France. The objective was to derive a low and protective cadmium concentration in edible seaweeds to limit cadmium overexposure in consumers. To do so, we applied a probabilistic approach to the data collected on French seaweed consumers, taking into account other sources of exposure for cadmium. This approach led to the identification of a cadmium concentration which should ensure that the seaweed-consuming population does not exceed the tolerable daily intake (TDI) of cadmium according to a probability of cases, when simultaneously exposed to other cadmium dietary sources. Considering the 5% of the population exceeding TDI, the estimated ML is equal to 0.35 mg Cd kg^-1dry matter of seaweed as an unprocessed food with a 95% confidence interval of [0.18,1.09]. The proposed approach is generic and could be applied to other relevant food/substance pairs when considering the setting of MLs in the regulatory system. It ensures better protection of consumer health.

Seaweed-Derived Phlorotannins: A Review of Multiple Biological Roles and Action Mechanisms

Phlorotannins are a group of phenolic secondary metabolites isolated from a variety of brown algal species belonging to the Fucaceae, Sargassaceae, and Alariaceae families. The isolation of phlorotannins from various algal species has received a lot of interest owing to the fact that they have a range of biological features and are very biocompatible in their applications. Phlorotannins have a wide range of therapeutic biological actions, including antimicrobial, antidiabetic, antioxidant, anticancer, anti-inflammatory, anti-adipogenesis, and numerous other biomedical applications. The current review has extensively addressed the application of phlorotannins, which have been extensively investigated for the above-mentioned biological action and the underlying mechanism of action. Furthermore, the current review offers many ways to use phlorotannins to avoid certain downsides, such as low stability. This review article will assist the scientific community in investigating the greater biological significance of phlorotannins and developing innovative techniques for treating both infectious and non-infectious diseases in humans.

Metal Contamination of Oman Sea Seaweed and Its Associated Public Health Risks

Oman Sea region is a major gateway for international and local shipping. Metal pollution of aquatic environment is primarily caused by such shipping and industrial activities. Agricultural runoffs are also of concern. Seaweed contamination with heavy metals in this area is therefore a distinct possibility. We examined seaweed of Oman Sea for heavy metal content and potential risk of its consumption to the public. During winter of 2019, water, sediment, and seaweed were collected along twelve stations on the coast of Oman Sea. Triplicates of each sample were analyzed for metal content by atomic absorption spectroscopy. Biomarkers of metals in seaweed (metallothionein and phytochelatin) were also analyzed. A significant positive correlation exists among levels of Zn, Ni, Pb, Cr, Cu, and Fe in water, sediment, and seaweed (P < 0.05). Cadmium correlations were weak. The highest levels of metallothionein and phytochelatin were found in brown and red seaweed (118.6 µg/g wet weight, 16.4 amol/cell; 111.4 µg/g ww, 12.1 amol/cell), respectively. For nickel and lead, human consumption of red, brown, and green seaweed was associated with "some health hazard," with a target hazard quotient of > 1. We conclude that concerns over heavy metal contamination of some parts of Oman Sea are valid, and we invite policy makers to implement measures for protection of public and environment from metal toxic effects in the region.

Scavenging of select radionuclides and trace elements by pelagic Sargassum in the Caribbean Sea

In recent years, the North Atlantic and the Caribbean Sea have experienced unusual and unprecedented pelagic Sargassum blooms, which may adversely affect coastal ecosystems and productive ocean. Sargassum has the potential to scavenge trace elements and radionuclides from seawater, and when bioaccumulated and thus concentrated, can pose a potential threat to higher trophic organisms, including humans that consume impacted seafood. In this study, trace elements and naturally-occurring U/Th-series radionuclides were measured in Sargassum that were collected in the coastal waters of the Caribbean Sea (Antigua/Barbuda, Belize, and Barbados) to better define baseline concentrations and activities, and to assess the scavenging potential for these trace elements and radionuclides. The mean concentration of trace elements observed in Sargassum collected across these three Caribbean Sea are ranked accordingly to the following descending order: Sr > As>Fe > Mn > Zn > Ni > V > C > Cd > Se > Co > Cr > Pb > Ag > Hg. 210-Po and 210Pb activities in Sargassum were observed to be more elevated than previously reported values.

Determination of Antioxidant, Antimicrobial Activity, Heavy Metals and Elements Content of Seaweed Extracts

The aim of the research was to determine the antioxidant and antimicrobial activity, determination of chemical elements and heavy metals in seaweed extracts of wakame, arame, dulse, laminaria, kombu, and hijiki. Antioxidant activity was determined by DPPH method and the activity ranged from 0.00 to 2641.34 TEAC. The highest antioxidant activity was observed in kombu (2641.34 TEAC) and arame (2457.5 TEAC). Antimicrobial activity was analyzed by disk diffusion method and MIC method. Three G+ bacteria (Staphylococcus aureus, Enterococcus faecalis, Bacillus subtilis), three G- bacteria (Salmonella enterica, Pseudomonas aeruginosa, Yersinia enterocolitica), and four yeasts (Candida tropicalis, C. krusei, C. glabrata, C. albicans) were used as model organisms. The size of inhibition zones ranged from 0.00 to 8.67 mm. The minimum inhibitory concentrations of the selected seaweeds ranged from MIC50 98.46 (MIC90 100.25) to MIC50 3.43 µL/mL (MIC90 5.26 µL/mL). The content of selected elements was determined in seaweed samples by ICP-OES. The chemical composition of the algae showed differences between species and the presence of heavy metals. Arsenic, cadmium, and aluminum were confirmed. All seaweed samples contained arsenic ranging from 6.6546 to 76.48 mg/kg. Further investigation of seaweeds is needed to identify the active substances present in the algae that are responsible for antioxidant and antimicrobial activity. This study was carried out to evaluate the antimicrobial and antioxidant activity of extracts from five commonly consumed seaweeds for their ability to inhibit selected microorganisms and to determine the health risk due to heavy metals content. Our study contributes to the evidence that seaweeds have antimicrobial and antioxidant activity and seaweed extracts have for pharmacological applications.

Freshwater Macrophytes: A Potential Source of Minerals and Fatty Acids for Fish, Poultry, and Livestock

The freshwater macrophytes are abundant in tropical and subtropical climates. These macrophytes may be used as feed ingredients for fish and other animals. The nutritional value of twelve freshwater-cultured macrophytes was evaluated in the present study. Significantly higher crude protein (36.94–36.65%) and lipid (8.13–7.62%) were found in Lemna minor and Spirodela polyrhiza; ash content was significantly higher in Hydrilla verticillata, Wolffia globosa, and Pistia stratiotes (20.69–21.00%) compared with others. The highest levels of sodium, magnesium, chromium, and iron levels were recorded in P. stratiotes. H. verticillata was a rich source of copper, manganese, cobalt, and zinc; the contents of calcium, magnesium, strontium, and nickel were highest in S. polyrhiza. Selenium and potassium contents were higher in Salvinia natans and W. globosa, respectively. The n-6 and n-3 polyunsaturated fatty acids (PUFAs) contents were significantly higher in W. globosa and Ipomoea aquatica, respectively compared with others. Linoleic and α-linolenic acids were dominant n-6 and n-3 PUFAs. The highest value (4.04) of n-3/n-6 was found in I. aquatica. The ratio ranged from 0.61 to 2.46 in other macrophytes. This study reveals that macrophytes are rich sources of minerals, n-6 and n-3 PUFAs.

The Biochemical Composition and Antioxidant Properties of Fucus vesiculosus from the Arctic Region

Fucus vesiculosus is one of the most prominent brown algae in the shallow waters of the seas of the Arctic region (Barents (BS), White (WS), Norwegian (NS), and Irminger (IS)). The aim of this study was to determine the biochemical composition of F. vesiculosus from the Arctic at different reproductive phases, and to evaluate the antioxidant properties of F. vesiculosus extracts. The amounts of monosaccharides, phlorotannins, flavonoids, and ash and the mineral composition significantly varied in the algae. A strong correlation was established between monosaccharide, phlorotannin, and flavonoid accumulation and water salinity (Pearson’s correlation coefficients r = −0.58, 0.83, and 0.44, respectively; p < 0.05). We noted a negative correlation between the antioxidant activity and the amount of the structural monosaccharides of fucoidan (r = −0.64). A positive correlation of phlorotannins and flavonoids with antioxidant power was confirmed for all samples. The ash accumulation was relatively lower in the sterile phase for the algae from the BS and WS. The correlation between the Metal Pollution Index (MPI) and the reproductive phases was medium with high fluctuation. Meanwhile, the MPI strongly correlated with the salinity and sampling site. The gradient of the MPI values across the sea was in the following ranking order: BS < WS < NS < IS. Taken together, and based on our data on the elemental contents of F. vesiculosus, we believe that this alga does not accumulate toxic doses of elements. Therefore, the Arctic F. vesiculosus could be safely used in food and drug development as a source of active biochemical compounds and as a source of dietary elements to cover the daily nutritional requirements of humans.

First assessment of Atlantic open ocean Sargassum spp. metal and metalloid concentrations

Over the last decade, increasing proliferations of Atlantic Sargassum populations have led to massive beaching with disastrous environmental consequences. This study is a preliminary assessment of open ocean Sargassum spp. element concentration to assess their potential contribution on coastal ecosystems. Sargassum spp. samples from seven sites, collected along a transect from the center of the Atlantic Ocean to near the coast of Martinique (French West Indies), were analyzed to determine their potential metal and metalloid enrichment. Mean element concentrations from the Sargassum spp. samples were ranked in the following descending order: As > Fe > Mn > Al > Zn > V > Ni > Cu > Cr > Cd > Hg. Element concentrations are relatively low compared to previous results of beached Sargassum spp. except for As that need to be carefully considered before reusing Sargassum spp.

Pharmaceuticals and Personal Care Products in the Marine Environment Around False Bay, Cape Town, South Africa: Occurrence and Risk-Assessment Study

Pollution of the marine environment has been increasing as a result of anthropogenic activities. The preservation of marine ecosystems as well as the safety of harvested seafood are nowadays a global concern. In the present study, levels of pharmaceuticals and personal care products were assessed in different environmental compartments in the near-shore marine environment of False Bay, Cape Town, South Africa. The study revealed the presence of these persistent chemical compounds in different environmental samples from this location. Diclofenac was the most dominant compound detected, with higher concentration than the other pharmaceutical compounds, as well as being present in almost all the samples from the different sites (seawater, 3.70-4.18 ng/L; sediment, 92.08-171.89 ng/g dry wt; marine invertebrates, 67.67-780.26 ng/g dry wt; seaweed, 101.50-309.11 ng/g dry wt). The accumulation of pharmaceuticals and personal care products in the different species of organisms reflects the increasing anthropogenic pressure taking place at the sampling sites along the bay, as a result of population growth, resident lifestyle as well as poorly treated sewage effluent discharge from several associated wastewater-treatment plants. The concentration of these contaminants is in the order marine biota > sediments > seawater. The contaminants pose a low acute and chronic risk to the selected trophic levels. A public awareness campaign is needed to reduce the pollution at the source, as well as wastewater discharge limits need to be more stringent. Environ Toxicol Chem 2022;41:614-634. © 2021 SETAC.

Distribution and safety assessment of heavy metals in fresh meat from Zhejiang, China

There are increasing concerns on heavy metals in animal derived foods. We analyzed the levels of As, Cd, Cr, Cu, Hg, Ni, and Pb in 1066 fresh meat samples including pork, beef, mutton, chicken and duck from Zhejiang province, southeast China. The average levels of As, Cd, Cr, Cu, Hg, Ni, and Pb were 0.018, 0.002, 0.061, 0.801, 0.0038, 0.055, and 0.029 mg/kg wet weight respectively. There are significant positive correlations among Cd, Hg and Pb (P < 0.05) and negative correlations for Cu–Pb or Cu–Cd (P < 0.05). The exposure assessment showed that the health risk to humans by consuming these meat products was relatively low. However, regular monitoring of heavy metals in meat products is still recommended considering their intensive industrial activities.

Accumulation of essential (copper, iron, zinc) and non-essential (lead, cadmium) heavy metals in Caulerpa racemosa, sea water, and marine sediments of Bintan Island, Indonesia

Background: Heavy metals are materials naturally occurring in nature and increase with a rise in human activity. Ex-mining areas and domestic waste from human settlements are sources of heavy metal contamination that enter and pollute water, which then accumulates in various organisms including the  Caulerpa racemosa community. The accumulation of heavy metals in  C. racemosa has a wide impact on the food chain in aquatic ecosystems and humans because this alga is a consumptive commodity.  

Methods: Sampling of  C. racemosa was carried out at seven sites on Bintan Island, Indonesia covering the eastern (Teluk Bakau, Beralas Pasir, Malang Rapat), northern (Berakit and Pengudang), western (Sakera), and southern parts (Tg. Siambang). Sampling was carried out during different monsoons, and heavy metals in water and sediment samples were measured to determine the heavy metal concentration. Heavy metals were analyzed by a spectrophotometric method using Atomic Absorption Spectrophotometry.  

Results: The results showed that heavy metal concentrations fluctuate according to changes in the wind season, which carry currents and spread pollutants into the water. The concentration of metal in the water is also from anthropogenic activities. The heavy metal content of cadmium (Cd), lead (Pb), copper (Cu), iron (Fe), and zinc (Zn) in  C. racemosa is high in locations close to settlements. Meanwhile, in seawater samples, Fe and Zn metals have the highest concentrations compared to others. 

Conclusions: Ex-bauxite mines are a source of Fe and Zn metal contamination in the environment, especially at Tg. Siambang. The levels of these heavy metals in the sediment are also high, as surface particle deposits accumulate at the bottom of the sediment. In general, the levels of heavy metals Cd, Pb, Cu, Fe, and Zn increase in the northern monsoon because the dynamics of the water transport greater heavy metal pollution.

Increasing Seaweed Consumption in the Netherlands and Portugal and the Consequences for the Intake of Iodine, Sodium, and Exposure to Chemical Contaminants: A Risk-Benefit Study

Background: Seaweed has a high potential for nourishing the future planet. However, besides being beneficial, it also contains adverse components; this poses the question whether consumption of seaweed foods overall contributes beneficially or detrimentally to human health, and hence if their consumption should be promoted or restricted. Methods: This study evaluated the impact of substituting regular foods with seaweed foods in the diet, both in terms of nutritional quality (via iodine and sodium) and food safety (via arsenic, cadmium, lead, and mercury). Food consumption data from the Netherlands and Portugal (adults aged >18 years) were used, in which 10% of the amounts of pasta, bacon, and lettuce consumed were replaced by seaweed-derived products made from kelp (Saccharina latissima). Using Monte Carlo Risk Assessment software (MCRA), long-term nutrient intake and exposure to contaminants were assessed. The results obtained for the Netherlands and Portugal were compared with data from Japan, a country that has a high natural consumption of seaweed. Results: This low-tier risk-benefit study reveals that an increased seaweed consumption (as assessed by the 10% replacement with seaweed products) has no consequences in terms of intake of sodium and exposure to cadmium, lead, and mercury, and the associated (absence of) adverse health aspects. The alternative scenario almost doubled the mean iodine intake in the Netherlands (to 300 μg/day) and Portugal (to 208 μg/day) and increased the average exposure to arsenic levels in the Netherlands (to 1.02 μg/kg bw/day) and Portugal (to 1.67 μg/kg bw/day). Conclusion: The intake of iodine and exposure to arsenic in the Netherland and Portugal were certainly higher due to the modeled increase of seaweed foods. If seaweed consumption increases close to the 10% substitution, the public health consequences thereof may trigger further research.

Seaweed consumption in France: Key data for exposure and risk assessment

Seaweeds accumulate toxic contaminants present in the surrounding waters such as trace elements, ammonium, dioxins and pesticides. Seaweed consumption data are scarce in France as in Europe. Given that seaweed consumption data are essential to assess exposure and the risks for human health linked to toxic substances, it would appear essential to generate these data. The aim of the study was to assess the current consumption of seaweed foodstuffs by the French population via an online survey conducted on 780 adults (seaweed foodstuffs consumed, percentage of consumers and frequency of consumption). The daily consumption of seaweeds was assessed. Enquiries at points of purchase were also performed to reference the type of foodstuffs found on the French market, the seaweed species present, and the percentage of seaweed in the product. These new data generated in this work will be useful for safety assessors and for safety agencies.

Current knowledge and future perspectives of the use of seaweeds for livestock production and meat quality: a systematic review

The effects of dietary macroalgae, or seaweeds, on growth performance and meat quality of livestock animal species are here reviewed. Macroalgae are classified into Phaeophyceae (brown algae), Rhodophyceae (red algae) and Chlorophyceae (green algae). The most common macroalga genera used as livestock feedstuffs are: Ascophyllum, Laminaria and Undaria for brown algae; Ulva, Codium and Cladophora for green algae; and Pyropia, Chondrus and Palmaria for red algae. Macroalgae are rich in many nutrients, including bioactive compounds, such as soluble polysaccharides, with some species being good sources of n-3 and n-6 polyunsaturated fatty acids. To date, the incorporation of macroalgae in livestock animal diets was shown to improve growth and meat quality, depending on the alga species, dietary level and animal growth stage. Generally, Ascophyllum nodosum can increase average daily gain (ADG) in ruminant and pig mostly due to its prebiotic activity in animal's gut. A. nodosum also enhances marbling score, colour uniformity and redness, and can decrease saturated fatty acids in ruminant meats. Laminaria sp., mainly Laminaria digitata, increases ADG and feed efficiency, and improves the antioxidant potential of pork. Ulva sp., and its mixture with Codium sp., was shown to improve poultry growth at up to 10% feed. Therefore, seaweeds are promising sustainable alternatives to corn and soybean as feed ingredients, thus attenuating the current competition among food-feed-biofuel industries. In addition, macroalgae can hinder eutrophication and participate in bioremediation. However, some challenges need to be overcome, such as the development of large-scale and cost-effective algae production methods and the improvement of algae digestibility by monogastric animals. The dietary inclusion of Carbohydrate-Active enZymes (CAZymes) could allow for the degradation of recalcitrant macroalga cell walls, with an increase of nutrients bioavailability. Overall, the use of macroalgae as feedstuffs is a promising strategy for the development of a more sustainable livestock production.

Macroalgae in biomonitoring of metal pollution in the Bay of Bengal coastal waters of Cox's Bazar and surrounding areas

Although coastal water marine algae have been popularly used by others as indicators of heavy metal pollution, data within the Bay of Bengal for the estuarine Cox's Bazar region and Saint Martin's Island has remained scarce. Using marine algae, the study herein forms an effort in biomonitoring of metal contamination in the aforementioned Bangladesh areas. A total of 10 seaweed species were collected, including edible varieties, analyzed for metal levels through the use of the technique of EDXRF. From greatest to least, measured mean metal concentrations in descending order have been found to be K > Fe > Zr > Br > Sr > Zn > Mn > Rb > Cu > As > Pb > Cr > Co. Potential toxic heavy metals such as Pb, As, and Cr appear at lower concentration values compared to that found for essential mineral elements. However, the presence of Pb in Sargassum oligocystum species has been observed to exceed the maximum international guidance level. Given that some of the algae species are cultivated for human consumption, the non-carcinogenic and carcinogenic indices were calculated, shown to be slightly lower than the maxima recommended by the international organizations. Overall, the present results are consistent with literature data suggesting that heavy metal macroalgae biomonitoring may be species-specific. To the best of our knowledge, this study represents the first comprehensive macroalgae biomonitoring study of metal contamination from the coastal waters of Cox's Bazar and beyond.

Assessment of the surface water quality improvement during pandemic lockdown in ecologically stressed Hooghly River(Ganges) Estuary, West Bengal, India

The countrywide COVID-19 pandemic lockdown accomplished what aggressive plans could not do throughout the long-term cleaning of the Ganga River. Here, we illustrated Hooghly River surface water quality [physico-chemical parameters, biological parameters, dissolved heavy metals] improvement by analyzing eight sampling station before and during the lockdown. Because of shutdown of industrial units and individuals staying at home, a complete decrease in industrial wastes, contaminants, and self-purging of the stream improved significantly water quality by about 40% to 50%. Among dissolved heavy metals, the concentrations of Cd (50%), Pb (53%), demonstrated noteworthy variations during the lockdown. Diminishing trends were also observed for TDS (62%), and BOD (52%), with significant reduction in the total coliform (63%), faecal coliform (61%), notably. Principal component analysis and paired t-test signify the alteration of water quality. The study concludes that the aquatic ecosystem can be revived if wastewater, and anthropogenic activities are properly managed by environmental surveillance.

An Investigation of Toxic Metal Levels (Pb, Cd, Cr, As, Hg) in Dried Porphyra and Laminaria Collected from Coastal Cities, China

This investigation was aimed at determining the concentration levels of five toxic heavy metals (lead, cadmium, chromium, arsenic, and mercury) in dried Porphyra and Laminaria samples from coastal city of China. Inductively coupled plasma-mass spectrometry (ICP-MS) was used for determination of lead, cadmium and total arsenic. Atomic fluorescence spectrometry was used for mercury, and liquid chromatography coupled with ICP-MS was used for arsenic speciation. The mean concentrations of lead, cadmium, chromium, total arsenic, and mercury were 0.96 ± 0.03 mg/kg, 2.62 ± 0.07 mg/kg, 1.64 ± 0.08 mg/kg, 36.67 ± 0.53 mg/kg, and 7.56 ± 0.42 μg/kg for Porphyra samples and 0.61 ± 0.03 mg/kg, 0.48 ± 0.02 mg/kg, 3.78 ± 0.56 mg/kg, 43.85 ± 1.42 mg/kg, and 46.61 ± 2.02 μg/kg for Laminaria samples. The results were comparable with previous similar research. The potential health risk assessment was conducted by comparing the calculated weekly intakes of toxic metals from Porphyra and Laminaria with provisional tolerable weekly intake. Consumption of these seaweeds does not seem to pose a risk for the consumers' health regarding their content of heavy metals. However, the potential health risk of cadmium should not be overlooked for consumers with high intake of Porphyra.

Nature-Based Biomaterials and Their Application in Biomedicine

Natural polymers, based on proteins or polysaccharides, have attracted increasing interest in recent years due to their broad potential uses in biomedicine. The chemical stability, structural versatility, biocompatibility and high availability of these materials lend them to diverse applications in areas such as tissue engineering, drug delivery and wound healing. Biomaterials purified from animal or plant sources have also been engineered to improve their structural properties or promote interactions with surrounding cells and tissues for improved in vivo performance, leading to novel applications as implantable devices, in controlled drug release and as surface coatings. This review describes biomaterials derived from and inspired by natural proteins and polysaccharides and highlights their promise across diverse biomedical fields. We outline current therapeutic applications of these nature-based materials and consider expected future developments in identifying and utilising innovative biomaterials in new biomedical applications.

Seaweeds as a “Palatable” Challenge between Innovation and Sustainability: A Systematic Review of Food Safety

Moderate or severe food insecurity affect 2 billion people worldwide. The four pillars of food security (availability, access, use and stability) are in danger due to the impact of climatic and anthropogenic factors which impact on the food system. Novel foods, like seaweeds, have the potential to increase food yields so that to contribute in preventing or avoiding future global food shortages. The purpose of this systematic review was to assess microbiological, chemical, physical, and allergenic risks associated with seaweed consumption. Four research strings have been used to search for these risks. Preferred Reporting Item for Systematic Reviews and Meta-analysis (PRISMA) guidelines were applied. Finally, 39 articles met the selected criteria. No significant hazards for microbiological, allergenic, and physical risks were detected. Regarding chemical risk, algae can accumulate various heavy metals, especially when harvested in polluted sites. Cultivating seaweeds in a controlled environment allows to avoid this risk. Periodic checks will be necessary on the finished products to monitor heavy metals levels. Since the consumption of algae seems to be on the rise everywhere, it seems to be urgent that food control authorities establish the safety levels to which eating algae does not represent any risk for human health.

Health risk assessment of heavy metals in marine fish to the population in Zhejiang, China

Environmental pollution with toxic metals can lead to the possible contamination of the marine fish. We investigated the levels of As, Cd, Cr, Hg and Pb in 652 marine fish samples (15 species) collected from coastal areas of Zhejiang, China and estimated their health risk. Mean concentrations of As, Cd, Cr, Hg and Pb were 0.783, 0.009, 0.114, 0.031, 0.043 mg/kg wet weight. The average estimated daily intakes (EDIs) for As, Cd, Cr, Hg and Pb were 1.214, 0.014, 0.177, 0.048 and 0.067 μg/kg bw/day. The risk assessment at mean exposure level showed that there was no health risk associated with these elements through consumption of marine fish. However, potential health risk may exist for high exposure consumers considering the possible contamination of As and Hg. Given that the different levels of certain elements in marine fish in China, this study provides a scientific basis for food safety assessment and suggestions for risk management.

Uncovering Prospective Role and Applications of Existing and New Nutraceuticals from Bacterial, Fungal, Algal and Cyanobacterial, and Plant Sources

Nutraceuticals are a category of products more often associated with food but having pharmaceuticals property and characteristics. However, there is still no internationally accepted concept of these food-pharmaceutical properties, and their interpretation can differ from country to country. Nutraceuticals are used as part of dietary supplements in most countries. They can be phytochemicals which are biologically active and have health benefits. These can be supplied as a supplement and/or as a functional food to the customer. For human health and longevity, these materials are likely to play a vital role. Consumption of these items is typical without a therapeutic prescription and/or supervision by the vast majority of the public. The development of nutraceuticals can be achieved through many bioresources and organisms. This review article will discuss the current research on nutraceuticals from different biological sources and their potential use as an agent for improving human health and well-being, as well as the gaps and future perspective of research related to nutraceutical development.