Health risk assessment: heavy metals in fish from the southern Black Sea

Risk assessment of toxic residues among some freshwater and marine water fish species

Egypt has several beaches, as well as the Nile River and a few lakes; therefore, it could compensate for the lack of protein in red meat with fish. Fish, however, may become a source of heavy metal exposure in humans. The current study was to assess the level of five toxic metals, lead (Pb), cadmium (Cd), mercury (Hg), arsenic (As), and aluminum (Al), in six species, namely, Oreochromis niloticus (O. niloticus), Mugil cephalus (M. cephalus), Lates niloticus (L. niloticus), Plectropomus leopardus (P. leopardus), Epinephelus tauvina (E. tauvina), and Lethrinus nebulosus (L. nebulosus), collected from the El-Obour fish market in Egypt. The residual concentrations of the tested toxic metals in the examined O. niloticus, M. cephalus, L. niloticus, E. tauvina, P. leopardus, and L. nebulosus species were found to be higher than the European Commission's maximum permissible limits (MPL) for Pb and Cd by 10 and 20%, 15 and 65%, 75 and 15%, 20 and 65%, 15 and 40%, and 25 and 5%. In contrast, 30% of L. niloticus exceeded the MPL for Hg. It was shown that the average estimated daily intake (EDI) and the target hazard quotient (THQ) in fish samples are below safety levels for human consumption and hazard index (HI < 1). From the human health point of view, this study showed that there was no possible health risk to people due to the intake of any studied species under the current consumption rate in the country.

Determination of Heavy Metal Levels and Health Risk Assessment of Raw Cow Milk in Guelma Region, Algeria

During the recent decades, adverse effects of unexpected contaminants, such as heavy metals on raw cow milk quality, have threatened human health. The objective of this study was to determine heavy metal levels in raw milk collected from autochthonous bovine breeds in the eastern region of Algeria. Eighty-eight pooled milk samples were analyzed using atomic absorption spectrometry for Pb, Cd, Cr, Cu, Ni, Fe, and Zn, and dietary risks were estimated for infants, children, and adults with minimum, average, and maximum milk consumption scenarios. Results revealed that Pb (0.94 ± 0.49 mg/kg), Cd (0.03 ± 0.01 mg/kg), and Cu (0.14 ± 0.08 mg/kg) levels in all analyzed samples were higher than their corresponding maximum residue levels (MRLs). The task hazard quotient (THQ) values suggest potential risk for infants in the three scenarios from Pb, Cd, and Cr; for children in the three scenarios from Pb and in the high scenario from Cr; and for adults in the medium and high scenarios from Pb. The hazard index (HI) values were higher than 1, and the contributions of each metal to the overall HI followed a descending order of Pb, Cr, Cd, Ni, Zn, Cu, and Fe with values of 68.19%, 15.39%, 6.91%, 4.94%, 3.42%, 0.88%, and 0.28%, respectively. Our results indicated that there may be a potential risk of heavy metals, especially Pb, for infants through raw cow milk consumption. Moreover, data actualization and continuous monitoring are necessary and recommended to evaluate heavy metal effects in future studies.

Heavy Metals in Unprocessed or Minimally Processed Foods Consumed by Humans Worldwide: A Scoping Review

Heavy metals (HM) can be accumulated along the food chain; their presence in food is a global concern for human health because some of them are toxic even at low concentrations. Unprocessed or minimally processed foods are good sources of different nutrients, so their safety and quality composition should be guaranteed in the most natural form that is obtained for human consumption. The objective of this scoping review (ScR) is to summarize the existing evidence about the presence of HM content (arsenic (As), lead (Pb), cadmium (Cd), mercury (Hg), methylmercury (MeHg), and aluminum (Al)) in unprocessed or minimally processed foods for human consumption worldwide during the period of 2011–2020. As a second objective, we identified reported HM values in food with respect to Food and Agriculture Organization of the United Nations (FAO) and the World Health Organization (WHO) International Food Standards for Maximum Limits (MLs) for contaminants in food. This ScR was conducted in accordance with the Joanna Briggs Institute (JBI) methodology and PRISMA Extension for Scoping Reviews (PRISMA-ScR); advance searches were performed in PubMed, ScienceDirect and FAO AGRIS (Agricultural Science and Technology Information) databases by two reviewers who independently performed literature searches with specific eligibility criteria. We classified individual foods in food groups and subgroups according to the Global Individual Information Food Consumption Data Tool (FAO/WHO GIFT). We homologated all the reported HM units to parts per million (ppm) to determine the weighted mean HM concentration per country and food group/subgroup of the articles included. Then, we compared HM concentration findings with FAO/WHO MLs. Finally, we used a Geographic Information System (GIS) to present our findings. Using our search strategy, we included 152 articles. Asia was the continent with the highest number of publications (n = 79, 51.3%), with China being the country with the largest number of studies (n = 34). Fish and shellfish (n = 58), followed by vegetables (n = 39) and cereals (n = 38), were the food groups studied the most. Fish (n = 42), rice (n = 33), and leafy (n = 28) and fruiting vegetables (n = 29) were the most studied food subgroups. With respect to the HM of interest, Cd was the most analyzed, followed by Pb, As, Hg and Al. Finally, we found that many of the HM concentrations reported exceeded the FAO/OMS MLs established for Cd, Pb and As globally in all food groups, mainly in vegetables, followed by the roots and tubers, and cereals food groups. Our study highlights the presence of HM in the most natural forms of food around the world, in concentrations that, in fact, exceed the MLs, which affects food safety and could represent a human health risk. In countries with regulations on these topics, a monitoring system is recommended to evaluate and monitor compliance with national standards. For countries without a regulation system, it is recommended to adopt international guidelines, such as those of FAO, and implement a monitoring system that supervises national compliance. In both cases, the information must be disseminated to the population to create social awareness. This is especially important to protect the population from the consumption of internal production and for the international markets of the globalized world.

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.

Farmed Turkish salmon: Toxic metals and health threat

Introduction. Toxic metals in fish, even at low levels, have negative consequences for human health. Even essential metals pose a health threat if consumed in certain quantities. Mercury, cadmium, and lead are the most frequent metals containing in fish. The research objective was to inspect the quality of aquaculture fish found in most major grocery chains across Turkey. Study objects and methods. The present research featured the quantities of Zn, Fe, Cu, Al, Pb, Hg, and Cd in Turkish salmon. The sampling took place between February and June 2019. The cumulative carcinogenic and non-carcinogenic risk for consumers was evaluated based on trace element levels in a prospective health risk assessment using the U.S. EPA model of lifetime exposure. Results and discussion. Fe proved to be the most abundant element in fish fillets, followed by Zn and Cu. Other elements appeared to be far below the permissible values, namely Al ≤ 0.5, Cd ≤ 0.02, Pb, and Hg ≤ 0.05. All the trace elements detected in Turkish salmon were below the reference dose values. The percent contribution to total risk by Fe, Cu, and Zn were 34.20, 24.80, and 41.01%, respectively. The hazard index was ≤ 1. The contamination of aquaculture fish fillet proved insignificant, and the carcinogenic risk was entirely negligible. Conclusion. The research revealed no hazardous trace elements, and their cumulative effects were not indicated in the hazardous index.

Heavy metal concentration levels and biometric analysis of Liocarcinus depurator from different locations on the western Black Sea coast of Turkey

The aim of the current work is to examine the concentrations of nine heavy metals such as chromium, nickel, copper, cadmium, zinc, cobalt, iron, lead, and metal (aluminium) in two body parts (carapace and walking legs) of Liocarcinus depurator from different stations (İlyas bey, Cide koyu, Anadolu feneri, igneada) in the western Black Sea coast of Turkey. And this study was carried out to examine morphological properties of Liocarcinus depurator in the region. The sex ratio (female/male) of 387 samples was calculated as F/M = 1:0.945. The mean carapace length and width were measured as 20.41 ± 2.41 mm and 25.10 ± 2.78 mm for female and 25.49 ± 3.33 mm and 32.32 ± 4.50 mm for male individually. The mean weight of crabs was measured as 4.09 ± 1.37 g for females and 8.33 ± 3.35 g for males. The samples were investigated trace metals by inductively coupled plasma-optical emission spectrometry (ICP-OES). Ranges over trace metals in all samples of L. depurator as follows: Cr 0.6-1.5, Mn 21-130, Cu 8-37, Zn 6-40, Cd 0.2-1.5, Pb 0.1-3.6, Co 0.1-1.1, Fe 22-160, and Ni 0.6-1 mg/kg wet wt. The walking legs and carapace/exoskeleton of female and male crabs were analyzed and contained various concentrations of Pb, Co, Ni, Cr, Cd, Fe, Cu, Zn, and Mn elements. The order of the heavy metal in all samples of L. depurator is shown as Fe > Cu > Mn > Zn > Cr > Cr > Ni > Cd > Pb > Co. In this research, metal levels of the crab samples compared between female and male and found highest mean metal concentrations in the station number 3 (Anadolu feneri) that the Al concentration in the carapace of female was 295.0 mg/kg wet wt and in the walking legs was 306.67 mg/kg wet wt, in the carapace of male was 264.4 mg/kg wet wt, and in the walking legs was 162.61 mg/kg wet wt in station number 3 (Anadolu feneri). The purpose of this work is to analyze the metal composition of this type of crab, which is abundant in the Black Sea region and is not planned to be attached to fisherman's nets, to evaluate whether it will be useful or not.

Concentration and potential health risks of trace metals in warty crab (Eriphia verrucosa Forskal, 1775) from Southern Coasts of the Black Sea, Turkey

The drastic increase of human population and industrial wastes mostly affects coastal areas. Crabs with limited mobility, especially in benthic regions of the coasts, are more affected by metal pollution. Monitoring of trace metals in terms of food safety and potential health risks is important for consumers. Warty crab (Eriphia verrucosa) samples were collected with trammel nets between July 2015 and June 2016. The crab extracts were analyzed by an ICP-MS optical emission spectrophotometer. Trace metal densities of crab meats in the present study were determined in the order of Zn > Cu > Fe > As > Al > Mn > Hg > Pb ≥ Cd. These levels were below the acceptable values reported by the Turkish Food Codex and the EU Commission. The target hazard quotient (THQ) was above 1 in terms of As, Cu, and Hg trace metals in both groups. This study showed that although the level of trace metal was below allowable values, consumption of warty crab more than once a month may cause metal toxicity according to potential health risk analyses.

Cadmium, Lead, Copper, Zinc, and Iron Concentration Patterns in Three Marine Fish Species from Two Different Mining Sites inside the Gulf of California, Mexico

In the Gulf of California; mineral deposits have contributed to high metal contents in coastal environments. This study examined cadmium; lead; copper; zinc; and iron contents in three fish species; Kyphosus vaigiensis (herbivore), Stegastes rectifraenum (omnivore), and Balistes polylepis (carnivore) at two mining sites. Metal concentrations were analyzed by atomic absorption spectrophotometry and stable nitrogen and carbon isotopes were estimated using mass spectrophotometry. Also, we assessed the risk to human health from the consumption of these three species based on permissible limits; although only two of them (Kyphosus and Balistes) are consumed as food. Metal concentrations differed among fish species; except for iron. The highest concentrations of metals were not always recorded in the species at the highest trophic level; i.e., Balistes. The highest concentrations (dry weight) recorded were cadmium (0.21 ± 0.03 µg g^-1) and lead (1.67 ± 0.26 µg g^-1), in S. rectifraenum; copper (1.60 ± 0.49 µg g^-1) and zinc (67.30 ± 8.79 µg g^-1), in B. polylepis; and iron (27.06 ± 2.58 µg g^-1), in K. vaigiensis. Our findings show that each element accumulates differently in particular marine organisms; depending on the physiology of the species and the biogeochemistry of its habitat; which in turn is affected by the anthropogenic activities in adjacent areas. No risk of heavy metals toxicity is expected from the human consumption of the species and sites studied.