Lipophilic Marine Biotoxins in Mussels from Bulgarian coast and Dietary Intake of Different Population Groups

Abstract

<jats:title>Abstract</jats:title><jats:sec id="S0029665120002736_sec_a1" sec-type="intro"><jats:title>Introduction</jats:title><jats:p>Lipophilic phycotoxins, produced by toxic phytoplankton species, accumulate in digestive glands of mussels. If contaminated mussels containing marine biotoxins over regulatory levels are consumed, it is assumed that this could result in e.g. gastrointestinal disorders.</jats:p></jats:sec><jats:sec id="S0029665120002736_sec_a2" sec-type="other"><jats:title>Objectives</jats:title><jats:p>The aim of the study was to report contamination level of lipophilic marine biotoxins and to assess the potential health risk based on dietary intake for regular consumers and recreational harvesters from Bulgaria.</jats:p></jats:sec><jats:sec id="S0029665120002736_sec_a3" sec-type="other"><jats:title>Method/Design</jats:title><jats:p>Wild and cultivated mussels were sampled in spring seasons of 2017 and 2018 from the North Black Sea coast. Positive phycotoxins concentrations determined via LC-MS/MS in extracts from digestive glands of the mussels were converted in phycotoxin levels for whole mussel meat (mm) by applying a factor of 5 proposed by EFSA. Dietary intakes were calculated by multiplying the mean positive phycotoxin levels (mg /kg mm) by the food consumption data for an average body weight (bw) of the investigated population group.</jats:p></jats:sec><jats:sec id="S0029665120002736_sec_a4" sec-type="results"><jats:title>Results and discussion</jats:title><jats:p>In total 20 farmed and 15 wild mussel samples were investigated. Yessotoxins and pectenotoxin-2 were detected. The mean YTX levels in cultivated mussels were measured about two times higher in spring 2018 (1.64 mg/kg) than in 2017 (0.70 mg/kg). The mean YTX level in wild mussels was found much lower - 0.46 mg/kg (spring 2017). In this regard, estimation of mean dietary YTX intake show that exposure of both population groups by consumption of cultivated mussels from spring 2018 is highest. Nevertheless, the regulatory threshold – acute reference dose of 25 μg/kg bw, is much above the highest calculated dietary intake (0.006 μg/kg female consumers). The mean PTX2 level in wild mussel samples from spring 2017 (0.71 mg/kg) was found about six times higher than in farmed mussels.</jats:p><jats:p>The calculation of mean dietary PTX2 intake indicate that most exposed are females if wild mussels from spring 2017 were consumed. Still, the calculated value – 0.003 μg/kg bw were much lower than the ARfD - 0.8 μg/kg bw. All wild mussel samples from spring 2018 were negative. Lowest exposure to detected toxins were established for recreational harvesters.</jats:p></jats:sec><jats:sec id="S0029665120002736_sec_a5" sec-type="conclusions"><jats:title>Conclusion</jats:title><jats:p>This study showed in general low contamination level with YTX and PTX2 of investigated mussel samples. Thereon, the estimated dietary intake of selected population groups is also much lower than the regulatory thresholds.</jats:p></jats:sec>

Black Sea Mussels Qualitative and Quantitative Chemical Analysis: Nutritional Benefits and Possible Risks through Consumption

“…Our results are in accordance with findings of other studies conducted in order to assess potential human risks associated with mussel consumption in the region of Black Sea [ 54 , 55 , 56 ]. It should be noted also that calculated hazard quotients for investigated heavy metals within the current research were higher than values found in other investigated food categories in Romania (honey, food supplements) [ 57 , 58 ].…”

“…Even if HQs were below the critical value 1, so no possible risks are associated with mussel consumption collected from the study areas, we noted the case of lead which registered the highest calculated HQs from all heavy metals: 0.2 in A1, 0.03 in A3, 0.012 in A2, respectively. Our results are in accordance with findings of other studies conducted in order to assess potential human risks associated with mussel consumption in the region of Black Sea [54][55][56]. It should be noted also that calculated hazard quotients for investigated heavy metals within the current research were higher than values found in other investigated food categories in Romania (honey, food supplements) [57,58].…”

New Knowledge on Distribution and Abundance of Toxic Microalgal Species and Related Toxins in the Northwestern Black Sea

“…In addition, the reported levels of DSTs in mussel samples from the Black Sea were far below the regulatory limit [ 24 , 25 ]. Therefore, the risk of significant DSP toxin outbreaks in the northwestern Black Sea is low, as also reported by other authors [ 87 ].…”

“…The low levels of YTXs in plankton and previously measured in mussel samples [ 24 , 25 , 87 ], and the reported low oral toxicity of YTX analogues [ 96 , 97 ], suggest a negligible risk of acute intoxication in the western part of the Black Sea. On the other hand, the persistent presence of yessotoxins could result in chronic exposure from shellfish consumption, which might pose a threat to human health [ 98 ].…”

“…YTX was the major toxin variant, but was detected at levels much lower (up to 40 ng NT −1 ) than those reported in San Jorge Gulf, Argentina (8040 ng NT −1 ) [ 88 ]. Yessotoxins, tentatively related to Lingulodinium polyedra and Gonyaulax spinifera , have been detected earlier from Black Sea mussel samples [ 24 , 25 , 29 , 87 ], but toxins have not been found in plankton [ 24 ]. Strong relationships were found between Lingulodinium polyedra cell numbers and all of the detected YTX variants (except #17/18/19).…”