INTRODUCTIONThere is growing concern about chronicdiseases such as obesity, diabetes, hypertension,hypercholesterolemia, cancer, and cardiovasculardisease resulting from lifestyle changes worldwide [1].According to a study by S. Shab-Bidar and A. Jayedi,an increase in fish consumption of 100 g/day can reduceoverall and cardiovascular mortality, as well as the riskof coronary heart disease, myocardial infarction, stroke,heart failure, depression, and liver cancer. It has noeffect on other kinds of cancer. Therefore, fish can beconsidered a healthy source of animal protein [2].Oceans cover over 70% of the earth’s surface andprovide an enormous ecosystem for a wide varietyof marine species. These species are a rich source ofbioactive compounds that can be used in medicine,pharmacology, and food industry [3].A number of recent foreign studies have focusedon using the by-products of processing fish, marineinvertebrates, and plants. These by-products are oftendiscarded as waste, although they contain such valuablecomponents as high-quality proteins, lipids, minerals,vitamins, enzymes, and other bioactive compounds thatcan be used to fight cancer and some cardiovasculardiseases [1, 3, 4].Nutrition affects our general health and the state ofour individual functional systems. Therefore, it shouldnot only be balanced and adequate to gender, age, andthe degree of one’s physical and mental activity, butalso take into account the climatic and geographicconditions, as well as national characteristics and habits.It is especially relevant to the northern regions of Russia.Fish is an essential component of human diet thatprovides more than 3 billion people worldwide with about 20% of animal protein [5]. The global fish catchis 182 million tons per annum, of which 2.6–4.5% isproduced in Russia [6]. The Far Eastern basin accountsfor 64% of the all-Russian catch. Its white fish, salmon,shrimp, squid, and sea kale are the most popularproducts among consumers. The global productionof pink salmon caviar is 173,000 tons, of which 27%(46,700 t) is produced in Russia (30,900 t in the Sea ofOkhotsk). Russia boasts its saffron cod (40,500 t/year),commander squid (150,000 t/year), blue-throated halibut(400 kg/year), and kelp (3,800–9,800 t/year). Shrimpdominates among the crustaceans, but its annualproduction of 10,000–20,000 tons only satisfies 20% ofthe Russian demand [6].Fishing is the leading industry in many coastalregions of Russia, especially in the North and the FarEast, where it is the main source of income. PrimorskyKrai produces about 50% of all fish in the Far East,followed by Kamchatka and Sakhalin that equallyshare 2/5 of the total catch. The Magadan Region isalso becoming an important player in the Russian fishmarket. The Far Eastern Basin has 26 million tons ofaquatic biological resources, producing 3 million tons offish per year. An average Russian consumes 16.1 kg fishper year.Frozen, lightly salted, and smoked fish, as well ascheap canned fish, are among the most popular productsin Russia. There is a growth in the consumption ofultra-processed products, which is associated with thestandard of living in the country. There is a growingdemand for fish delicacies, valuable species of fish,shrimp, crabs, and other invertebrates, as well as caviar,among high-income population [7].According to the federal statistics of 2000 vs. 2019,the annual capita consumption of fish and fish productsgrew from 14.3 to 21.9 kg and from 12.7 to 22.3 kg inurban and rural areas, respectively. In 2019, the urbancitizen consumed 13.9 kg of live and frozen fish andseafood, 4.1 kg of salted, smoked, and dried fish andseafood, 2.1 kg of canned fish, and 1.0 kg of semifinishedand finished fish products. These indicators fora rural consumer were 14.8 kg, 4.6 kg, 1.8 kg, and 0.6 kg,respectively. The data for 2018 were almost identical tothose for 2019 [8].Fish has a more diverse mineral composition thanmeat, mainly due to microelements [9, 10]. While fishand meat have similar amounts of macronutrients(0.2% phosphorus, 0.3% potassium, 0.1% calcium),the content of some microelements in fish is 10 timeshigher (20–150 μg/g iodine, 140–700 μg% fluorine,40–50 μg% bromine). Fish is only low in iron (1 mg%).Other microelements in fish include cobalt (about20 mg%; 3–4 times more than in meat), zinc (1 mg%),copper (0.1 mg%), nickel (6 mg%), and molybdenum(4 mg%). Its average contents of sodium (100 mg%)and chlorine (165 mg%) are 2–3 times higher than inmeat. The total content of minerals in marine fish isabout 1.5 times as high as meat. Thus, fish and fishproducts are an essential source of minerals in humandiet. We should also note that fish, especially predatoryfish, can accumulate some toxic elements – mercury(up to 0.7 mg/kg), lead (up to 2.0 mg/kg), and cadmium(up to 0.2 mg/kg). However, these concentrations arewithin permissible levels and, when fish is consumed ingenerally accepted amounts, they do not pose any healthhazard [7].Non-fish species – crustaceans (crabs, shrimps,lobsters, crayfish), cephalopods (squid, octopus),bivalves (oysters, mussels, scallops), as well as algae(kelp, or sea kale) – contain potassium, sodium,calcium, magnesium, chlorine, sulfur, iron, manganese,phosphorus, aluminum, zinc, and many other macroandmicroelements [11]. There is scientific evidencethat fish species from tropical areas contain highconcentrations of calcium, iron, and zinc, while thosefrom cold seas or pelagic seas and oceans are rich inomega-3 fatty acids [12].Earlier, we determined the contents of macroandmicroelements in muscle tissue and testes ofanadromous fish of the salmon (Salmoidae L.),chum salmon (Oncorhynchus keta L.), coho salmon(Oncorhynchus kisutch L.), and pink salmon(Oncorhynchus gorbuscha L.) caught in the coastal Seaof Okhotsk, Magadan Region. These species are mostfrequently eaten by the local population [13]. We foundthat the interspecific differences in the levels of elementsin their biosubstrates were within the permissiblestandards for food products. However, chum salmonhad larger amounts of arsenic, cobalt, copper, sodium,tin, antimony, and zinc than coho salmon. The levelof iron in chum salmon and coho salmon was similarto that in freshwater fish. The contents of potassiumand phosphorus were quite high, while the contentsof lead, mercury, antimony, cadmium, arsenic, andcobalt were significantly below the standards. We alsofound that the element system of the indigenous smallnumberedpeoples, who have a traditional way of lifein the Magadan Region, was in a better state than theelement system of the Caucasian group, despite theimbalance in chemical elements seen in all the groups.This was probably due to the genetic adaptation of thenortherners’ mineral metabolism to the chronicallyinsufficient intake of macro- and microelements, as wellas their diet.In this work, we determined the contents ofchemical elements in the muscle tissue of some speciesof fish and seafood, as well as in algae, native to theSea of Okhotsk. These products are the most essentialcomponents in the diet of the indigenous northernpeoples and general inhabitants of the coastal northernregions. The population of the Magadan Region hasa «northern» profile of macro- and microelementswith a deficiency of calcium, cobalt, magnesium, zinc,selenium, and iodine [13]. Therefore, we aimed toanalyze (qualitatively and quantitatively) the mineralcomposition of some species of marine life in order to304Stepanova E.M. et al. Foods and Raw Materials, 2021, vol. 9, no. 2, pp. 302–309determine whether the consumption of marine fish andseafood can satisfy the recommended daily requirementfor minerals.STUDY OBJECTS AND METHODSThe objects of research were: Far Eastern or Pacificsaffron cod (Eleginus gracilis, n = 1 0), b lack o r b lueheadedhalibut (Reinhardtius hippoglossoides, n = 10),commander squid (Berryteuthis magister, n = 10),cooked and frozen northern shrimp (Pandalus borealis,n = 10), salted pink salmon caviar (Oncorhynchusgorbuscha, n = 10), and kelp (Laminaria, n = 10) or seakale. All the objects were caught in the Sea of Okhotsk,the Magadan Region. Each sample of 50 g was packed ina polypropylene container. The contents of macro- andmicroelements were determined threefold and averaged.Our study methods included the inductively coupledplasma atomic emission spectrometry (ICP-AES) andthe inductively coupled plasma mass spectrometry(ICP-MS) applied with Optima 2000 DV and Agilent8900 ICP-MS instruments (Perkin Elmer, USA).The study was carried out in line with GuidelinesNo. 4.1.985-00 “Determination of toxic elements infood products and raw materials. The autoclave samplepreparation technique” and in cooperation with theMicronutrients Company (Moscow).The study objects were analyzed for the followingmacro- and microelements: aluminum (Al), arsenic (As),boron (B), calcium (Ca), cadmium (Cd), cobalt (Co),chromium (Cr), copper (Cu), iron (Fe), mercury (Hg),iodine (I), potassium (K), lithium (Li), magnesium (Mg),manganese (Mn), sodium (Na), nickel (Ni), phosphorus(P), lead (Pb), selenium (Se), silicon (Si), tin (Sn),antimony (Sr), vanadium ( V), and zinc (Zn).For statistical analysis, we calculated the averagemeasurement error (M ± m) and tested the normality offrequency distribution. When testing null hypotheses,the critical level of statistical significance was P < 0.05.Raw product portions of 100 g were used to determinethe degree to which the fish and seafood speciessatisfied the daily adult requirement for macro- andmicroelements. For this, we referred to the “Standardphysiological requirements for energy and nutrients forvarious population groups in the Russian Federation”(Methodological Guidelines 2.3.1.2432-08).The macro- and microelement status of the workingagepopulation in Magadan was examined in compliancewith the Declaration of Helsinki and the principlesof biomedical ethics. Each participant (study subject)voluntarily provided a written informed consent in linewith Federal Law No. 323 “On Health Protection in theRussian Federation” of November 21, 2011 and FederalLaw No. 152 “On personal data” of July 27, 2006.We examined a total of 111 men (70 men aged22–35 and 41 men aged 36–60) and 270 women(120 women aged 21–35 and 150 women aged 36–55).Hair samples from the back of the head were used asbiomaterial for elemental analysis. They were exposedto inductively coupled argon plasma mass spectrometryon an Agilent 8900 ICP-MS instrument in the samelaboratory to determine the contents of 25 macroandmicroelements: Al (aluminum), As (arsenic),B (boron), Be (beryllium), Ca (calcium), Cd (cadmium),Co (cobalt), Cr (chromium), Cu (copper), Fe (iron),Hg (mercury), I (iodine), K (potassium), Li (lithium),Mg (magnesium), Mn (manganese), Na (sodium),Ni (nickel), P (phosphorus), Pb (lead), Se (selenium),Si (silicon), Sn (tin), V (vanadium), and Zn (zinc).The data were statistically processed with IBM SPSSStatistics 21.RESULTS AND DISCUSSIONTable 1 shows the average concentrations of essential(vital) macro- and microelements determined in theaquatic organisms and algae sampled from the Sea ofOkhotsk.We found that macronutrients differed significantlyacross almost all the studied species. Yet, kelp hada significantly higher (P < 0.05) content of calcium,potassium, and magnesium, accounting for 18, 50,and 37% of the daily requirement, respectively. Ourcalculations were based on 100 g portions of fresh (raw)products, since mineral loss during cooking was outsideour study objectives. According to literature, however,the loss of minerals in cooked products is less than10% [9]. Salted pink salmon caviar showed the highest(P = 0.01) concentrations of sodium and phosphorus of10040 and 4763 μg/g, respectively, amounting to 77 and60% of the daily intake.Our macroelement values slightly differed from theHandbook on the Chemical Composition and CaloricContent of Russian Foodstuffs published by the Instituteof Nutrition, the Russian Academy of Medical Sciences(hereinafter “Handbook”) [9]. Below are the values fromthe Handbook (with our values in brackets) for 100 gportions of the following species:– saffron cod: sodium – 70 mg% (114.4 mg%),potassium – 335 mg% (302.7 mg%), calcium –40 mg% (22.4 mg%), magnesium – 40 mg%(21.5 mg%), phosphorus – 240 mg% (200.6 mg%);– halibut: sodium – 55 mg% (140.5 mg%), potassium –450 mg% (188.6 mg%), calcium – 30 mg% (11.4 mg%),magnesium – 60 mg% (18.5 mg%), phosphorus –220 mg% (131.1 mg%);– pink salmon caviar: sodium – 2245 mg% (1004 mg%),potassium – 85 mg% (130.8 mg%), calcium – 75 mg%(60.9 mg%), magnesium – 141 mg% (69.6% mg%),phosphorus – 426 mg% (476.3 mg%);– boiled and frozen shrimp: sodium – 540 mg%(494.3 mg%), potassium – 220 mg% (143.4 mg%),calcium – 70 mg% (89.6 mg%), magnesium – 50 mg%(63.4 mg%), phosphorus – 225 mg% (128.2 mg%); and– squid: sodium – 110 mg% (468.4 mg%), potassium –280 mg% (160.5 mg%), calcium – 40 mg% (23.2 mg%),magnesium – 90 mg% (97.9 mg%), phosphorus –250 mg% (201.4 mg%).The differences might be associated with theparticular species [14] (in some cases, the Handbookonly gives the generic name without specifying the305Stepanova E.M. et al. Foods and Raw Materials, 2021, vol. 9, no. 2, pp. 302–309Table 1 Essential macro- and microelements (M ± m) in the muscle tissue of some species of marine life (the Sea of Okhotsk, Magadan)ME Pacific saffroncod EleginusgracilisBlack-headedhalibutReinhardtiushippoglossoidesCommandersquidBerryteuthismagisterNorthernshrimpPandalusborealisPink salmoncaviarOncorhynchusgorbuschaKelpLaminariaDailyrequirement% of daily adult requirement (in 100 g)MacroelementsCa 224 ± 221-2, 1-4, 1-5, 1-6114 ± 112-3,2-4, 2-5, 2-6232 ± 233-4, 3-5, 3-6896 ± 904-5, 4-6609 ± 615-62210 ± 221 1250 mg 1.8 0.9 1.9 7.2 4.9 17.7K 3027 ± 3031-2, 1-3, 1-4, 1-5, 1-61886 ± 1892-4, 2-5, 2-61605 ± 1613-61434 ± 1434-61308 ± 1315-612508 ± 1251 2500 mg 12.1 7.5 6.4 5.7 5.2 50.0Mg 215 ± 221-3, 1-4, 1-5, 1-6185 ± 182-3, 2-4, 2-5, 2-6979 ± 983-4, 3-5, 3-6634 ± 634-6696 ± 705-61482 ± 148 400 mg 5.4 4.6 24.5 15.9 17.4 37.1Na 1144 ± 1141-3, 1-4, 1-5, 1-61405 ± 1402-3, 2-4, 2-5, 2-64684 ± 4683-5, 3-64943 ± 4944-5, 4-610040 ± 10045-67982 ± 798 1300 mg 8.8 10.8 36 38 77.2 61.4P 2006 ± 2011-2, 1-4, 1-5, 1-61311 ± 1312-3, 2-5, 2-62014 ± 2013-4, 3-5, 3-61282 ± 1284-5, 4-64763 ± 4765-6547 ± 55 800 mg 25.1 16.4 25.2 16.0 59.5 6.8MicroelementsCu 0.392 ± 0.0471-2, 1-3, 1-4, 1-5, 1-60.181 ± 0.0222-3, 2-4, 2-52.52 ± 0.253-4, 3-68.26 ± 0.834-5, 4-62.99 ± 0.305-60.190 ± 0.023 1.0 mg 3.9 2.0 25.2 83.0 29.9 1.9Fe 3.42 ± 0.341-2, 1-3, 1-4, 1-5, 1-60.981 ± 0.1182-3, 2-4, 2-5, 2-66.01 ± 0.603-4, 3-5, 3-61.72 ± 0.174-5, 4-621.46 ± 2.155-680.72 ± 8.07 Male – 10 mg 3.4 1.0 6.0 1.7 21.5 80.72Female –15 mg 2.3 0.7 4.0 1.1 14.3 53.8I 6.0 ± 0.61-2, 1-3, 1-4, 1-5, 1-60.841 ± 0.1012-3, 2-5, 2-60.385 ± 0.0463-4, 3-5, 3-60.773 ± 0.0934-5, 4-67.81 ± 0.785-62319 ± 278 150 mcg >100% 56.1 25.7 51.5 >100% >100%Mn 0.122 ± 0.0151-2, 1-3, 1-4,1-5, 1-60.042 ± 0.0062-3, 2-4, 2-5, 2-60.553 ± 0.0663-4, 3-5, 3-60.186 ± 0.0224-5, 4-61.07 ± 0.115-60.960 ± 0.115 2.0 mg 0.6 0.2 2.8 0.9 5.4 4.8Se 0.509 ± 0.0611-2, 1-3, 1-4, 1-5, 1-60.338 ± 0.0412-5, 2-60.327 ± 0.0393-5, 3-60.265 ± 0.0324-5, 4-62.12 ± 0.21 0.020 ± 0.004 70 mcg 72.9 48.3 46.7 37.9 >100% 2.9Zn 10.64 ± 1.061-2, 1-5, 1-63.58 ± 0.362-3, 2-4, 2-5, 2-610.65 ± 1.063-5, 3-612.27 ± 1.234-5, 4-623.40 ± 2.345-62.78 ± 0.28 12 mg 8.9 3.0 8.9 10.2 19.5 2.3ME – macro- and microelements; daily requirements were taken from the “Standard physiological requirements for energy and nutrients for various population groups in the Russian Federation” (MethodologicalGuidelines 2.3.1.2432-08); 1-2 – reliably significant differences in the amounts of macro- and microelements (P < 0.05) among the samples.306Stepanova E.M. et al. Foods and Raw Materials, 2021, vol. 9, no. 2, pp. 302–309Table 2 Conditionally essential microelements (M ± m) in the biosubstrates of some species of marine life (the Sea of Okhotsk,Magadan)ME Pacific saffroncod EleginusgracilisBlue-headedhalibutReinhardtiushippoglossoidesCommander squidBerryteuthismagisterNorthernshrimpPandalusborealisPink salmoncaviarOncorhynchusgorbuschaKelpLaminariaDailyrequirementB 0.119 ± 0.0141-2, 1-3, 1-4, 1-5, 1-60.314 ± 0.0382-3, 2-4, 2-5, 2-61.83 ± 0.183-5,3-61.82 ± 0.184-5, 4-6<0.0215-621.15 ± 2.12 2.0 mgCo 0.0062 ± 0.001241-2, 1-4, 1-5, 1-60.0019 ± 0.000392-3, 2-4, 2-5, 2-60.0063 ± 0.001263-4, 3-5, 3-60.011 ± 0.0024-60.015 ± 0.002 0.020 ± 0.003 10 mcgCr 0.103 ± 0.0121-20.156 ± 0.0192-4, 2-60.128 ± 0.0153-40.08 ± 0.0124-50.117 ± 0.014 0.10 ± 0.012 50 mcgV 0.0073 ± 0.001461-2, 1-3, 1-60.0015 ± 0.000312-3, 2-4, 2-5, 2-60.0033 ± 0.000663-4, 3-5, 3-60.010 ± 0.0024-5, 4-60.0058 ± 0.00117 0.38 ± 0.046 15 mcgSi 20.25 ± 2.031-2, 1-3, 1-4, 1-612.55 ± 1.252-3, 2-4, 2-527.42 ± 2.743-5, 3-633.33 ± 3.334-5, 4-620.83 ± 2.085-612.66 ± 1.27 5.0 mgLi 0.012 ± 0.0021-2, 1-3, 1-4, 1-5, 1-60.023 ± 0.0042-3, 2-4,2-5,2-60.080 ± 0.0123-5, 3-60.079 ± 0.0124-5, 4-60.0051 ± 0.001025-60.130 ± 0.015 100 mcgNi 0.054 ± 0.0081-60.048 ± 0.0072-4, 2-5, 2-60.044 ± 0.0073-4, 3-5, 3-60.074 ± 0.011 0.062 ± 0.009 0.080 ± 0.012 n.a.Note: ME – macro- and microelements; 1-2 – reliably significant differences in the amounts of macro- and microelements (P < 0.05) among thesamples; n.a. – not availableTable 3 Toxic microelements (M ± m) in the biosubstrates of some species of marine life (the Sea of Okhotsk, Magadan)ME Pacific saffron codEleginus gracilisBlue-headed halibutReinhardtiushippoglossoidesCommander squidBerryteuthismagisterNorthern shrimpPandalus borealisPink salmon caviarOncorhynchusgorbuschaKelp Laminaria TPL mg/kg,max.I1,2 3–5 6Al 1.20 ± 0.12 0.864 ± 0.104 1.0 ± 0.1 0.867 ± 0.104 0.42 ± 0.05 1.82 ± 1.18 –As 27.19 ± 2.72 2.07 ± 0.21 0.849 ± 0.102 4.71 ± 0.47 0.294 ± 0.035 6.89 ± 0.69 5.0 5.0 5.0Cd 0.0024 ± 0.00048 0.0008 ± 0.00023 0.069 ± 0.010 0.075 ± 0.011 0.0016 ± 0.00033 0.130 ± 0.016 0.2 2.0 1.0Hg 0.034 ± 0.005 0.039 ± 0.006 0.027 ± 0.004 0.028 ± 0.004 <0.0036 0.05 ± 0.008 0.5 0.2 0.1Pb 0.0043 ± 0.00087 0.0045 ± 0.0009 0.0042 ± 0.00084 0.0031 ± 0.00061 0.0025 ± 0.00051 0.04 ± 0.006 1.0 10.0 0.5Sn 0.038 ± 0.006 0.004 ± 0.0008 0.0049 ± 0.00097 0.0052 ± 0.00104 0.0092 ± 0.00185 0.008 ± 0.0017 –Sr 0.817 ± 0.098 0.636 ± 0.076 4.37 ± 0.44 20.68 ± 2.07 5.42 ± 0.54 193 ± 19 –Note: ME – macro- and microelements; TPL – temporarily permissible levelI “Unified sanitary, epidemiological and hygienic requirements for products (goods) subject to sanitary and epidemiological surveillance (control)”(effective from June 1, 2019).species). Additional factors include their habitat,production season, and the methods used to determinemacro- and microelements.The significantly highest content of copper wasrecorded in the boiled and frozen shrimp sample (83%of the daily requirement). The maximum contents of ironand iodine were found in the kelp sample (54–81% andover 100%, respectively). The highest concentrations ofmanganese, selenium, and zinc were determined in pinksalmon caviar (5%, over 100%, and 19.5%, respectively).Of all aquatic products, pink salmon caviar wasanalyzed in a ready-to-eat salted form, since raw caviaris not stored or frozen. Its sodium content was extremelyhigh (10040 μg/g vs. the recommended intake of1300 mg/day), as can be seen in Table 1. However, evenif a daily diet includes other sodium-containing foods,one caviar sandwich a day will not pose any health risk.On the contrary, it will benefit health since caviar is richin phosphorus, iron, iodine, zinc, and valuable bioactivesubstances, such as omega-3-polyunsaturated fatty acidsand vitamins.The contents of conditionally essential elements arepresented in Table 2.The highest boron content was recorded in the kelpsample (21.15 μg/g or 106% of the daily requirementin 100 g). This trace element plays a significant role inthe formation of bone tissue by regulating the activityof parathyroid hormone and, therefore, the metabolismof calcium, magnesium, and phosphorus [15, 16]. Thismakes kelp an essential component in the northerners’diet. Also, kelp had higher concentrations of cobalt(2 μg or 20% of the daily requirement), vanadium (38 μgor 95%), and lithium (13 μg or 13%) than any other of thestudied samples. The maximum amount of chromiumwas determined in the muscle tissue of blue halibut(15.5 μg or 31% of the daily requirement). Northernshrimp was rich in silicon (3,333 mcg or 67% of thedaily requirement).307Stepanova E.M. et al. Foods and Raw Materials, 2021, vol. 9, no. 2, pp. 302–309We analyzed the concentrations of toxicmicroelements in the studied biosubstrates againstthe “Unified sanitary, epidemiological and hygienicrequirements for products (goods) subject to sanitaryand epidemiological surveillance (control)” (effectivefrom June 1, 2019) and the hygienic safety requirementsfor food products established in the TechnicalRegulations of the Customs Union “On food safety”(TR CU 021/2011). Excessive levels were only found forarsenic: 5.4 times as high in the Pacific saffron cod and1.4 times as high in the kelp sample (Table 3).Some studies report fluctuations in the content oftotal arsenic in various species of fish and shellfishfrom 5 to 200 μg/g (or mg/kg) [17, 18]. The Russianregulations specify certain contents of total arsenicin food products and materials without differentiatingbetween its inorganic (toxic) and organic (low-toxic)forms, which explains excess concentrations determinedin marine hydrobionts. Yet, we know that arsenic ismainly present in the tissues of marine life in its organic,low-toxic forms, such as arsenobetaine, arsenocholine,and arsenosugar [19]. This problem could be solvedby introducing an additional maximum permissibleconcentration for inorganic arsenic in marinehydrobionts into the regulatory documents, such as theTechnical Regulations of the Customs Union “On foodsafety” (TR CU 021/2011) [19].Besides, our long-term studies of the elementalstatus did not find any excessive contents of heavy andtoxic metals (including arsenic) in the population of theMagadan Region [13, 20].Thus, since the regulatory documents establishmaximum permissible concentrations of total, ratherthan organic, arsenic in marine life, we can concludethat the population of the Magadan Region is notexposed to a toxic load of arsenic.Rational nutrition involves a variety of foods in thediet, including those produced in other biogeochemicalregions that may have a negative impact on the localpopulation. Thus, the consumption of local foodwith a significant proportion of essential macro- andmicroelements is an effective way to prevent regionaldeficiency or excess of certain chemicals.According to our data, over 50% of the workingageresidents of Magadan have a deficiency of calciumand magnesium (most essential macroelements), as wellas cobalt and iodine (microelements). This deficiency,which is typical of the “northern” elemental profile, candecrease the northerners’ adaptive reserves. Moreover,a chronic deficiency of basic vital elements in extremenorthern conditions can cause dysfunctions in manyphysiological systems and a wide range of pathologies.The statistical data for the mineral metabolism in thestudy subjects are presented in Table 4.The studied cohorts showed obvious differencesrelated to both age and gender. In a linearapproximation, reliably significant (at P < 0.05)Table 4 Macro- and microelements in the hair samples of working-age residents of Magadan (25–75 percentile)ME Male study subjects Female study subjects Significance level (p)Aged 22–35 (n = 70) Aged 36–60 (n = 41) Aged 21–35 (n = 120) Aged 36–55 (n = 150) 1–2 3–4 1–3 2–4Al 10.00 (6.59–14.62) 11.69 (5.82–20.73) 7.62 (4.39–13.73) 7.85 (4.69–14.15) 0.50 0.52 0.02 0.04As 0.081 (0.046–0.117) 0.079 (0.046–0.185) 0.042 (0.042–0.062) 0.042 (0.027–0.072) 0.73 0.73 0.00 0.00Ca 265.42 (187.85–333.54) 310.60 (221.17–405.60) 449.47 (258.10–750.45) 473.00 (282.48–937.98) 0.07 0.17 0.00 0.00Cd 0.027 (0.013–0.052) 0.040 (0.013–0.122) 0.008 (0.004–0.016) 0.012 (0.006–0.034) 0.03 0.00 0.00 0.00Co 0.010 (0.006–0.018) 0.014 (0.008–0.074) 0.012 (0.007–0.022) 0.014 (0.008–0.033) 0.01 0.11 0.10 0.41Cr 0.73 (0.47–1.01) 0.56 (0.24–1.03) 0.35 (0.23–0.54) 0.36 (0.18–0.58) 0.10 0.88 0.00 0.00Cu 10.98 (9.87–12.28) 9.89 (8.57–12.54) 10.02 (8.41–11.61) 10.23 (8.99–11.56) 0.31 0.35 0.10 0.66Fe 18.22 (9.87–12.28) 22.42 (14.52–38.68) 20.35 (14.38–31.04) 18.39 (13.08–26.17) 0.19 0.07 0.37 0.06K 110.40 (44.76–170.75) 171.00 (73.92–515.07) 38.59 (17.27–77.09) 74.64 (32.62–200.12) 0.01 0.00 0.00 0.00Li 0.015 (0.012–0.027) 0.016 (0.010–0.036) 0.012 (0.012–0.017) 0.012 (0.011–0.022) 0.90 0.16 0.00 0.38Mg 26.85 (19.76–35.93) 27.01 (19.18–40.17) 33.75 (21.61–67.33) 49.41 (26.75–104.32) 0.69 0.01 0.00 0.00Mn 0.43 (0.28–0.69) 0.71 (0.42–0.95) 0.87 (0.43–1.67) 1.18 (0.48–2.31) 0.01 0.01 0.00 0.01Na 198.51 (62.81–413.94) 392.00 (189.99–866.15) 82.05 (40.52–180.23) 170.20 (79.57–575.95) 0.00 0.00 0.00 0.00Ni 0.22 (0.15–0.35) 0.29 (0.17–0.48) 0.18 (0.11–0.31) 0.17 (0.11–0.30) 0.24 0.94 0.07 0.02P 159.72 (143.80–173.99) 163.00 (149.50–186.12) 151.38 (137.55–165.90) 156.56 (140.38–180.53) 0.19 0.07 0.08 0.170Pb 0.48 (0.31–0.85) 1.12 (0.48–4.68) 0.16 (0.08–0.33) 0.25 (0.11–0.53) 0.00 0.00 0.00 0.00Se 0.38 (0.30–0.51) 0.51 (0.38–0.80) 0.34 (0.26–0.49) 0.46 (0.27–0.74) 0.00 0.00 0.22 0.30Si 32.98 (20.59–48.22) 21.33 (13.83–31.30) 28.81 (17.46–49.81) 23.92 (15.28–40.71) 0.00 0.05 0.58 0.30Sn 0.09 (0.06–0.18) 0.12 (0.07–0.20) 0.08 (0.04–0.20) 0.08 (0.04–0.17) 0.21 0.59 0.47 0.04V 0.12 (0.04–0.19) 0.04 (0.01–0.09) 0.04 (0.02–0.08) 0.05 (0.02–0.09) 0.01 0.73 0.00 0.74Zn 190.80 (166.86–217.14) 177.00 (131.79–208.30) 176.75 (154.51–211.83) 174.42 (147.13–200.36) 0.02 0.17 0.08 0.68I 0.67 (0.32–1.11) 0.74 (0.38–3.46) 0.49 (0.30–1.00) 0.55 (0.30–1.47) 0.34 0.89 0.37 0.14Hg 0.53 (0.20–0.89) 0.60 (0.37–0.99) 0.48 (0.30–0.67) 0.51 (0.35–0.68) 0.27 0.28 0.07 0.14B 0.81 (0.58–1.64) 0.89 (0.56–3.72) 0.56 (0.33–1.29) 0.76 (0.29–1.81) 0.29 0.33 0.20 0.12Be 0.003 (0.003–0.004) 0.003 (0.001–0.009) 0.003 (0.001–0.003) 0.003 (0.001–0.006) 0.27 0.14 0.27 0.70Note: ME – macro- and microelements; significant differences are highlighted in bold (p < 0.05).308Stepanova E.M. et al. Foods and Raw Materials, 2021, vol. 9, no. 2, pp. 302–309differences can be schematically represented as follows(common groups of elements are highlighted in bold).Gender-related differences:men (Si, V, Zn) ♂ 22-35 > < ♂ 36-60 (Cd, Co, K, Mn,Na, Pb, Se);women (Si) ♀21-35 > < ♀ 36-55 (Cd, K, Mg, Mn, Na,Pb, Se).Age-related differences:younger age (Al, As, Cd, Cr, K, Li, Na, Pb, V) ♂ 22-35> < ♀21-35 (Ca, Mg, Mn);older age (Al, As, Cd, Cr, K, Na, Ni, Pb, Sn) ♂ 36-60 >< ♀36-55 (Ca, Mg, Mn).Noteworthily, age-related differences in mineralmetabolism were common for men and women. Youngersubjects of both sexes had a significantly highermedian of Si concentration. The hair samples of oldersubjects contained significantly higher contents of toxiccadmium and lead, while no excess of these elementswas detected in any of the studied cohorts. In addition,older subjects had higher concentrations of essentialpotassium, manganese, sodium, and selenium. Thus,we can consider these elements age-related. At the sametime, they tended to be in excess at different degreesand frequency of detection, which can be considered asmineral pre-deficiency caused by its increased excretionfrom the body.Hormone-determined gender differences inmetabolism can be seen in the elemental status of menand women. The female subjects of both age groupshad significantly higher concentrations of essentialcalcium, magnesium, and manganese, while their malecounterparts had higher contents of aluminum, arsenic,cadmium, chromium, potassium, sodium, and lead. Ourdata were in line with some literature sources and ourearlier studies [13 , 20-22].Thus, every individual has unique mineralmetabolism that differs between men and women andchanges with age. We find it extremely important toregularly monitor the elemental status of the workingagepopulation in the North as a socially significantgroup. This measure will ease the growing pressure onfunctional reserves, maintain the immune system, andprevent various pathologies related to mineral imbalanceand severe deficiencies. People should support theirhealth, individually or under medical supervision, byrationalizing their nutrition and consuming preventativesupplements of macro- and microelements, taking intoaccount the specific features of the “northern” mineralmetabolism.The most common “northern” diseases of abiogeochemical nature include iron deficiency states(deficiency of iron, cobalt, magnesium, and calcium),immunodeficiency conditions (deficiency of selenium,zinc, iodine, and calcium), arthrosis (deficiency or excessof calcium and silicon), urolithiasis (excess calciumor silicon), hypertension (deficiency of magnesiumor calcium), dental diseases (imbalance of calcium,fluoride, and magnesium), and thyroid pathologies,most commonly endemic goiter (iodine deficiency andimbalance of selenium, copper, manganese, cobalt,calcium, magnesium, and other elements).CONCLUSIONWe determined the absolute contents of macroandmicroelements in some species of marine life andassessed the degree to which they could satisfy therecommended daily requirement for these mineralsif included in the daily diet. We compared mineralquantities in the studied species of marine fish, pinksalmon caviar, shellfish, and algae from the Sea ofOkhotsk. In addition, we examined the elemental statusof the coastal residents and specified deficiencies ofessential chemical elements common for this “northern”profile.We found that the studied species of marine lifenative to the Sea of Okhotsk in the Magadan Region area valuable source of macro- and microelements that, insome cases, satisfy over 100% of the daily requirementfor adult humans. However, the amounts of calcium andmanganese in the studied fish and non-fish products (100g) were lower than required. Therefore, we recommendreplenishing their deficiencies with other foods thatare rich in these minerals (dairy products and meat), aswell as bioactive supplements or pharmaceuticals undermedical supervision.Since the indigenous small-numbered northerners,who lead a traditional way of life, have minimumelemental imbalance and no clinical signs of endemicgoiter, we recommend that “outsiders” coming to live inthe area optimize their daily nutrition with local foods,mainly marine fish and non-fish products.CONTRIBUTIONThe authors were equally involved in writing themanuscript and are equally responsible for plagiarism.CONFLICT OF INTERESTThe authors declare no conflict of interest.