Identification of histamine in fish and fish products in Poland during 2014–2018

Introduction Histamine is one of the most important and toxic biogenic amines which may be present in food and may cause food poisoning in humans when contained at a high level. It is produced during bacterial decarboxylation of histidine in fish muscles. The aim of the study was to investigate the presence of histamine in fish and fish products available in Poland during 2014–2018. Material and Methods A total of 421 samples of raw (248), smoked (107), canned (50), and marinated fish (16) were analysed by high-performance liquid chromatography with diode array detection. Results Histamine was detected in 14.1% samples of raw fish, 29% of smoked fish, 22% of canned fish and 93.8% of marinated fish in concentrations ranging from 3.4 to 156.4 mg/kg. Content of this amine above 100 mg/kg was found in four samples: raw Atlantic salmon, smoked European sprat and two samples of marinated Atlantic herring. Conclusion The study showed that fish and fish products on the Polish market generally meet the food safety criteria for histamine and are safe for consumers.

Heavy Metal Concentrations in Fish from River Tano in Ghana and the Health Risks Posed to Consumers

Appreciable levels of trace metals have been reported in the Tano basin, but data on the corresponding levels in fish and the risk they pose to consumers are limited. The levels of 7 trace metals in 18 fish muscles were assessed between November 2016 and October 2017 using acid digestion and PerkinElmer (PinAACle 900T) Atomic Absorption Spectrophotometry. Apart from Cu, all the metals studied were detected in all fish samples. The levels of Cr, As, and Hg were higher than the acceptable levels of fish muscles. Cr concentration ranged from 16.10 ± 0.2 mg/kg in Clarias gariepinus to 57.9 ± 4.2 mg/kg in Sarotherodon galilaeus. The levels of As ranged from 1.01 ± 0.08 in Clarias gariepinus to 3.00 ± 0.01 mg/kg in Mormyrus rume. Hg level was 0.58 ± 0.69 mg/kg in Oreochromis niloticus and 2.52 ± 0.70 mg/kg in Ctenopoma kingsleyae. However, Pb, Zn, and Cd concentrations were below the Food and Agriculture Organization limits with low target hazard quotients in all fish samples, suggesting no possible noncarcinogenic risks to adult consumers. Possible noncarcinogenic and carcinogenic health risks were recorded for As, Hg, and Cr in all fish species. Strong associations were observed between Hg, As, Zn, and Cr and between Pb and Cd suggesting a possible common source. Mormyrus rume fish species was under stress in the river, but the remaining species were in good condition. Periodic monitoring of trace metal concentrations in fish and enforcement of the buffer zone policy are recommended.

Human Health Risk Assessment and Histopathological Alterations in Puntius sophore of Damsal Nala, Sukinda Chromite Valley, Odisha, India

The aim of the present study was to assess the concentration of potentially toxic metals (PTMs) like As, Cd, Cr, Cu, Fe and Pb in the Damsal Nala of Sukinda Chromite Valley, Jajpur of Odisha (India) and its subsequent histopathological lesions in the fish Puntius sophore. Energy Dispersive X-Ray Fluorescence (EDXRF) and Flame Atomic Absorption Spectroscopy (FAAS) methods were used to evaluate the concentrations of PTMs in the muscles of fish, Puntius sophore collected from different zones namely upstream discharge zone (UDZ) and upstream zone (UZ) of the Damsal Nala and control water bodies (CW). In the UDZ of Nala, the concentration of metals viz., Cd, Pb and Fe were 2 to 7 times, and Cr was 77 times higher than the maximum permissible limits recommended by WHO and FAO in the fish muscles. The values of Target Hazard Quotients (THQ) of all these 6 metals were <1 in CW and UZ, but in UDZ the THQ values of Cr and Fe were >1. Hazard Index (HI) for UDZ was 3.47, indicated the alarming concentration of metal which can pose serious risk to human health. Histopathological observations in liver and kidney of Puntius sophore collected from UDZ demonstrated the serious lesions, but mild damage in fish collected from UZ. These histological alterations and the health risk indices disclosed the effects of effluents of chromite mining and the impact on the ecological balance which may result into health hazards to the local human population who are maintaining their livelihood by consuming these fish as protein source.

Comparative Study of Antioxidant Activity and ROS Production Profile among Clarias batrachus, Cirrhinus reba, Channa punctatus (Freshwater Species)

Fish account fifty percent of entire vertebrates present on the planet. They can be found practically in every possible aquatic habitats; from the 39,900 species of vertebrates, 21,723 are fishes with 8,411 being freshwater species while 11,650 being marine. There are about 2,500 species of fishes are present in India out of which 930 of them living in freshwater and 1,570 in the ocean. So, in the present study, we collected three fresh water fish’s i.e. Clarias batrachus, Cirrhinus reba, Channa punctatus from the river Mahanadi. Information on the comparative account of antioxidant protection in these fishes from Mahanadi river is relatively scanty. As a result, the purpose of this research was to explore the proximate composition of the three popularly used Fresh water fish species from the river Mahanadi. The result of the present study involved an integrated study of muscle tissue of C. batrachus, C. reba and C. punctatus which shows alteration in lipid per oxidation, hydrogen peroxide and antioxidant defence system. Results of this investigation suggest that C. reba were considered as a highly proteinaceous fish for which they are widely used in food industries. Still, more research work is required to explore the nutritional value of various types of fish muscles and their products.

Mechanism of Delayed Convulsion in Fish: The Actions of Norepinephrine in Spinal Cord

Cranial spiking (CS) is among the most popular slaughtering methods for delaying the rigor mortis progress of fish muscles. However, it may cause a convulsion (subsequently referred to as delayed convulsion), which undermines the meat quality and taste. This study aimed to elucidate the mechanism underlying the delayed convulsion and examine its influence on ATP consumption. Ten carps, nine tilapias, ten rainbow trouts, two ayus, three greenling, thirty-five red seabreams, two striped jack and two stone flounders underwent CS around the medulla oblongata area, which induced different delayed convulsion profiles specific to each species. To investigate the norepinephrine (NE) actions related to delayed convulsion, 27 red seabreams, a representative fish species that exhibits delayed convulsion, were treated with a monoamine-depleting agent, reserpine, or with a monoamine oxidase inhibitor, pargyline, two hours before CS. Spinal cord destruction (SCD) was employed to completely prevent spinal cord functions of the fish in another group. Compared with the control group (CS only), the reserpine, pargyline, and SCD groups showed significantly inhibited delayed convulsion and ATP consumption. This suggests that delayed convulsion is the main ATP-consuming response. Our findings suggest that delayed clonic convulsion in red seabreams is associated with the rapid decrease in spinal cord NE levels, which triggered the rebound motor neuron hyperactivity.

Hg Concentrations and Stable Isotopes Variations in Tropical Fish Species of a Gold-mining Impacted Watershed in French Guiana

The aim of the study was to determine if gold mining activities could impact the mercury (Hg) concentrations and isotopic signatures in freshwater fish consumed by riparian people in French Guiana. Total Hg, MeHg concentrations and Hg stable isotopes ratios were analyzed in fish muscles from different species belonging to three feeding patterns (herbivorous, periphytophagous and piscivorous). We compared tributaries impacted by gold-mining activities (Camopi, CR) with a pristine area upstream (Trois-Sauts, TS), along the Oyapock River. We measured δ15N and δ13C to examine whether Hg patterns are due to differences in trophic level. Differences in δ15N and δ13C values between both studied sites were only observed for periphytophageous fish, with enriched values at TS. Total Hg concentrations and Hg stable isotopes fractionations showed that Hg accumulated in fish from both areas have undergone different biogeochemical processes. Δ199Hg variation in fish (-0.5 to 0.2‰) was higher than the ecosystem baseline defined by a Δ199Hg of -0.66‰ in sediments, and suggested limited aqueous photochemical MeHg degradation. Photochemistry-corrected δ202Hg in fish were 0.7‰ higher than the baseline, consistent with biophysical and chemical isotope fractionations in aquatic environment. While THg concentrations in periphytophagous fish were higher in the gold-mining area than in TS, in contrast to the sediments results, the ensemble of Hg isotope shifts did not allow to trace and quantify the gold-mining related liquid Hg(0) sources in the fish muscles.

Burst-and-coast swimmers optimize gait by adapting unique intrinsic cycle

This paper addresses the physical mechanism of intermittent swimming by considering the burst-and-coast regime of fish swimming at different speeds. The burst-and-coast regime consists of a cycle with two successive phases, i.e., a phase of active undulation powered by the fish muscles followed by a passive gliding phase. Observations of real fish whose swimming gait is forced in a water flume from low to high speed regimes are performed, using a full description of the fish kinematics and mechanics. We first show that fish modulate a unique intrinsic cycle to sustain the demanded speed by modifying the bursting to coasting ratio while maintaining the duration of the cycle nearly constant. Secondly, we show using numerical simulations that the chosen kinematics by correspond to optimized gaits for swimming speeds larger than 1 body length per second.

Assessment of heavy metal concentrations in the muscles of ten commercial fish species from Lagos lagoon, NigeriaAssessment of heavy metal concentrations in the muscles of ten commercial fish species from Lagos lagoon, Nigeria

The study was undertaken to assess the concentration of five heavy metals (zinc (Zn), lead (Pb), copper (Cu), iron (Fe) and manganese (Mn)) in the muscles of Tilapia zilli, Hydrocynus fiscalis, Parapristipoma humile, Caranx hippo, Cynoglossusa caudatus, Chrysichthys nigrodigitatus, Letjanus sp, Portunus validus, Sardinella maderensis, and Sphyreana sp. The concentrations of heavy metals were measured by atomic absorption spectrophotometry after digestion of the samples. There were significant differences (P<0.05) in the concentration of heavy metals in fish muscles. There was no specific pattern in the levels of heavy metals among the fish species. P. validus had the highest concentration of Zinc in the fish sampled with a mean value of 14.45mg/g while T. zilli had the lowest concentrations of Zn and Mn. Sphyreana sp had the highest concentrations of Lead and Copper and Manganese in the muscles. Iron concentration was highest in the muscle of S. maderensis. In this study, the overall average concentrations of metals in fish muscles were in the order of Zn> Fe > Pb> Cu> Mn. The values of Zn and Cu were within or lower than the acceptable limits FAO/WHO (Food and Agriculture Organization Of the United Nations/World Health Organization) for concentration of heavy metals in fish while levels of Pb, Fe and Mn in the muscles of the various fishes were beyond the safe limit in foods. Close monitoring of heavy metal pollution of Lagos Lagoon is strongly advocated, in view of possible risks to the health of consumers.