Element Contents in Three Commercially Important Edible Mollusks Harvested off the Southwestern Coast of Crimea (Black Sea) and Assessment of Human Health Risks from Their Consumption

Assessment of persistent and emerging pollutants levels in marine bivalves in the Gulf of Suez, Egypt

Bivalves possess important ecological and economic values. They have been extensively used as bioindicators for both emerging and classical pollutants in the aquatic environment. This study investigates the levels of trace metals, polycyclic aromatic hydrocarbons (PAHs), and organochlorine pesticides (OCPs), alongside microplastic (MPs), in Tridacna maxima, Paphia textile, and Paratapes undulatus, collected from the Gulf of Suez. This work represents the first investigation of MPs in marine bivalves from the Gulf of Suez. MPs were detected in 72% of the specimens examined and four types of MPs were identified. The metal pollution index indicated that bivalves may have long-term toxic effects on human consumers. The results showed minimal hydrocarbon pollution. Diagnostic ratios indicated a combination of pyrolytic and petrogenic sources, with a notable influence from pyrolytic origins. The risk assessment reflected that the levels of certain trace metals, PAHs, and OCP contaminants could present a low risk to human health.

The mussel Mytilus galloprovincialis (Crimea, Black Sea) as a source of essential trace elements in human nutrition

Micronutrients, or essential trace elements, are important components in various metabolic processes inherent to the normal functioning of organism. To date, a substantial part of the world population suffers from a lack of micronutrients in the diet. Mussels are an important and cheap source of nutrients, which can be utilized to mitigate the micronutrient deficiency in the world. In the present work, using inductively coupled plasma mass spectrometry, the contents of the micronutrients Cr, Fe, Cu, Zn, Se, I, and Mo were studied for the first time in soft tissues, shell liquor, and byssus of females and males of the mussel Mytilus galloprovincialis as the promising sources of essential elements in the human diet. Fe, Zn, and I were the most abundant micronutrients in the three body parts. Significant sex-related differences in the body parts were detected only for Fe, which was more abundant in byssus of males, and Zn, which exhibited higher levels in shell liquor of females. Significant tissue-related differences were registered in the contents of all the elements under study. M. galloprovincialis meat was characterized as the optimal source of I and Se for covering the daily human needs. Regardless of sex, byssus turned out to be richer in Fe, I, Cu, Cr, and Mo in comparison with soft tissues, which fact allows recommending this body part for the preparation of dietary supplements to compensate for the deficiency of these micronutrients in the human body.

Rare earth elements in different body parts of the mussel Mytilus galloprovincialis (Crimea, Black Sea) and assessment of associated human health risks from its consumption

The rare earth element (REE) pollution in the hydrosphere has become a matter of serious concern lately. In this study, using inductively coupled plasma mass spectrometry, the REE contents in soft tissue, byssus and shell liquor of the mussel Mytilus galloprovincialis, as a potential REE pollution bioindicator, in the Black Sea were determined for the first time. The highest REE levels were observed in mussels from the seabed. The REE contents in byssus and shell liquor were higher than in soft tissue. In byssus, the contents of Y, La, Ce, Nd and Dy were the highest, whereas in shell liquor, the heavier REE and Sc were the most concentrated. No likely REE-associated risks from the mussel meat consumption were detected. In soft tissue and byssus, REE contents significantly correlated with that of silicon.

Elements in Soft Tissues of the Young Mediterranean Mussel Mytilus galloprovincialis Lam. 1819 Collected in Sevastopol Bay (Crimea, Black Sea): Effects of Age, Sex, Location, and Principal Morphometric Parameters

Although the mussel Mytilus galloprovincialis has been known for decades as an excellent bioindicator of trace element pollution in the marine environment, there is still no information on the effects of a suite of its principal morphometric parameters and age on trace element levels in soft tissues. In this work, using inductively coupled plasma mass spectrometry, we studied the contents of 72 elements in soft tissues of M. galloprovincialis aged 0.5-4, which were sampled at three stations within a relatively small water body, Sevastopol Bay. Significant effects of age and sampling location on the element contents and soft tissue dry-to-wet weight ratio were discovered. The effects of sex were not significant. It was presumed for the first time that the decrease in element content in the soft tissues of young mussels can be associated with the decrease in physiological needs for elevated contents of essential elements and intracellular water with age. Combinations of six principal morphometric parameters showed that a function of as few as three parameters (soft tissue dry weight, whole mollusk weight, and shell height, with by far the greatest contribution of the dry-to-total weight ratio) formed significant correlations with the contents of the largest possible number of elements (69-88% of the total number). For the first time, it was shown that linear discriminant analysis and canonical analysis of principal coordinates can be successfully used for tracing the exact origin of mussel samples within such a small water area. Canonical analysis of principal coordinates proved superior in the correct classification of the samples.

Trace elements in edible tissues of the veined rapa whelk (Rapana venosa) in the southern Black Sea, Türkiye: sex, monthly, and age variations and human consumer health risk

Coastal areas face significant pressures from a variety of human activities, owing primarily to population growth in these areas. Human activities produce a variety of contaminants, including trace metals, which are common forms of contamination that enter marine ecosystems. This study was carried out to provide information on trace element concentrations (Hg, Pb, Cd, Cu, and Zn) in the muscles of Rapana venosa (Valenciennes, 1846) available on Sinop coasts of the southern Black Sea and to evaluate the possible risk associated with their consumption. The minimum and maximum values (mg/kg wet weight) of trace elements in the edible tissue of R. venosa decreased in the following order: Zn (1.75-8.53) > Cu (0.41-4.6) > Cd (0.021-0.255) > Pb (0.013-0.037) > Hg (0.010-0.035). The measured levels of all the trace elements in the present study were lower than the limits permitted by the European Community Regulation (EU), Turkish guideline, and the UK Ministry of Agriculture, Fisheries and Food (MAFF). The hazard index value of Hg, Cd, Cu, and Zn for the veined rapa whelk is lower than standard 1, demonstrating that ingestion of this mollusk from the southern Black Sea does not result in overexposure to these contaminants. The risk index value for human cancer risk of Pb for all seasons was found to be insignificant. When comparing the levels of elements in males and females, significant differences were found in some months for all the metals. In general, the trace elements were detected in higher concentrations in females than in males. Both females and males have accumulated less trace elements with increasing age. This study was the first to show the distribution of trace elements as a function of age in R. venosa.

Trace elements in the detoxifying and accumulating body parts of Mytilus galloprovincialis Lamark, 1819 (Crimea, Black Sea): human health risks and effect of the sampling site location

The mussel M. galloprovincialis is one of the most popular species in world's mariculture and environment pollution bioindicators. Although this mollusk was in a focus of numerous publications, the detoxifying and accumulating role of some of its body parts was insufficiently studied. The goals of the present work were as follows: (a) to study the distribution of potentially toxic elements (Cr, Co, Ni, Cu, Zn, As, Cd, Hg, Pb) in soft tissues, byssus, and shell liquor of this bivalve as a function of sampling location in the Black Sea near the southwestern coast of Crimea and (b) to assess human health risks from consuming soft tissues of mussels cultivated on a mollusk farm. Multivariate analysis showed significant differences in the overall distribution of the elements among the body parts and sampling sites under consideration. The trace element contents in soft tissues of M. galloprovincialis decreased in the following order: Zn > Cu > As > Ni > Pb > Cd > Cr > Co > Hg. The noncarcinogenic hazard index from the cultivated mussel consumption was found to be well below one and the carcinogenic risk index was found within the tolerable limits, which indicate the safety of consuming these mussels for humans. Byssus of M. galloprovincialis was characterized as a perfect indicator of marine environment pollution with Ni, Cu, Pb, Сo, and Cr. For the first time, the concentrations of trace elements were determined in the shell liquor and the function of byssus and shell liquor as the systems of trace element excretion from soft tissues was demonstrated.

Heavy Metals and Arsenic in Soft Tissues of the Gastropod Rapana venosa (Valenciennes, 1846) Collected on a Mollusk Farm Off Sevastopol (Southwestern Crimea, Black Sea): Assessing Human Health Risk and Locating Regional Contamination Areas

The gastropod Rapana venosa is an edible mollusk suitable for biomonitoring of sea shelf contamination. In this work, the contents of five elements (Cu, Zn, As, Cd, Pb) in foot and in the rest of soft tissues of this mollusk were quantified, and the element contents in the edible foot were found below the maximum permissible levels set in several national and transnational regulations. The estimated daily intake of these elements and the hazard index indicated no likely risks to consumers' health, but the long-term cancer risks due to the arsenic intake were found significant. The arsenic and cadmium contents in soft tissues of this rapa whelk were among highest observed in the Black Sea region in the 2010s, and this suggests the specific arsenic and cadmium contamination of seawater off the southwestern Crimea. For the first time, this mollusk was shown to serve as a seawater contamination bioindicator at the regional level.