Formaldehyde In Fish Research Articles

Organoleptic quality and formaldehyde content of mackerel marketed in Dar es Salaam, Tanzania

BackgroundFish constitutes a nutritious food that deteriorates quickly when poorly preserved. Several biochemicals, including formaldehyde, accumulate naturally in the fish post-mortem. Apart from this natural formaldehyde, reports reveal the deliberate addition of formalin (37% formaldehyde solution) to the stored fish as a preservative. This is risky to consumers since formaldehyde is carcinogenic, genotoxic, and a potentiator of other carcinogens.AimThis study aimed to assess both the organoleptic quality and formaldehyde content of mackerels, the most consumed fish in Dar es Salaam, Tanzania.MethodsA total of 60 mackerel samples were conveniently and equally obtained from the local markets, street vendors, and supermarkets in five districts of the Dar es Salaam region. Organoleptic quality was evaluated based on organoleptic characteristics. Formaldehyde analysis was done by High-Performance Liquid Chromatography (HPLC). Analysis of variance was subsequently run to test the variation of formaldehyde content in mackerel by outlet type and district.ResultsAll analyzed mackerel samples had acceptable levels of organoleptic quality (2.46 ± 0.50) and a mean formaldehyde concentration of 10.89 ± 2.44 mg/kg. On average, the samples from supermarkets had the highest level of organoleptic quality (2.20 ± 0.21) but were also the most contaminated with formaldehyde (16.07 ± 4.68 mg/kg), while those from local markets were the least contaminated (3.91 ± 1.86 mg/kg) (p = 0.000). Moreover, 0% (n = 0), 20% (n = 4), and 35% (n = 7) of samples from local markets, street vendors, and supermarkets, respectively, had formaldehyde concentrations above 20 mg/kg, the previously estimated highest concentration for naturally formed formaldehyde in fish.ConclusionMackerels marketed in Dar es Salaam have acceptable organoleptic quality but are substantially contaminated with formaldehyde. Whether this is natural or artificial formaldehyde, our findings are inconclusive given the conflicting global standards. Nonetheless, the findings reveal the potential exposure of fish consumers to formaldehyde. Future research should explore the dynamics of the accumulation of natural formaldehyde in marketed fish and accurately assess the risk associated with the exposure of consumers to the formaldehyde in fish. The emanating findings will ultimately guide the development of local guidelines for natural and permissible formaldehyde concentrations in fish and fish products in Tanzania.

Qualitative detection of formaldehyde in challani fish obtained from selected fish markets of Nagaon, Assam, India

Preservatives are used to increase the shelf life of any product for a very long time, yet they are extremely detrimental to human health when used in food. The use of preservatives like formaldehyde by fishermen and fish merchants for prolonged preservation of fish during sales and transportation has recently become problematic and threat to human health. Therefore, the goal of the current investigation was to determine the presence of formaldehyde in the fish sold at fish markets in Nagaon, Assam. The present investigation indicates the contamination of fish with formaldehyde in the local fish markets of Nagaon district. The fish that show the presence of formaldehyde are imported (challani) and out of the whole fish sample collection (challani/imported), Labeo rohita, Catla catla indicates the highest positive result, with 35.96% and 48.44% respectively from the 114 Labeo rohita to 64 Catla catla samples. Additionally, the results for Ompok pabda, Pangasius pangasius, Hilsa ilisha, and Piaractus brachypomus are all positive, with Hilsa ilisha showing a positive result of 100% from their whole sample collection. However, the local fish like Labeo gonius, Cirrhinus reba, Ctenopharyngodon idella, Cirrhinus mrigala, and Hypophthalmicthys nobilis fish species have shown 100% negative results for formalin detection, indicating that their samples are formalin-free. Since formaldehyde is harmful to human health, better methods and techniques should be adopted for the preservation of fish for commerce and storage. Strict regulations should be put in place to limit the use of these hazardous chemical substances.

Design and Fabrication of a Capacitive Sensor for the Detection of Formaldehyde in Fish at Room Temperature

Design and Fabrication of a Capacitive Sensor for the Detection of Formaldehyde in Fish at Room Temperature

Mathematical Formulation to Differentiate between Naturally Occurred and Artificially Added Formaldehyde in the Ice Stored of Lizardfish (Saurida tumbil)

The practice of formaldehyde abuse as a food preservative, especially in fishery products, is commonly occurred. However, the differentiation of the formaldehyde origin in fish is difficult to be performed. Meanwhile, physical observation is not sufficient to determine the additional formaldehyde in fishery products. This study aimed to formulate a quantitative method to detect the origin of formaldehyde in fish. The formulation was developed based on the differences in some chemical properties (Formaldehyde (FA), Trimethylamine (TMA) and Trimethylamine oxide (TMAO) of fish treated with and without formaldehyde addition. The fish used as samples were beloso fish/lizardfish (Saurida tumbil). Fish were prepared with and without the addition of formaldehyde and then stored in ice for 21 days. The content of FA, TMA, and TMAO of gill and flesh during storage were analyzed every 3 days to determine the difference in the trend of distribution patterns of two fish treatments. The data were statistically processed to produce two mathematical formulas to identify the origin of formaldehyde. The results reveal that detection of the origin of formaldehyde in fish could be done using two approaches: the diffusion rate approach (validation 75-100%) and the ratio of formaldehyde, TMA, and TMAO (validation 96,47%).Keywords: Formaldehyde, fishery product, food preservative, mathematical formalulation, Surida tumbil

A review of the presence of formaldehyde in fish and seafood

Fish is an excellent source for high-quality protein, good fat (omega 3 and 6), vitamins (B, D), and minerals (Ca, P, Zn, I, Mg, K, etc.) and can lower blood pressure and help reduce the risk of a heart attack or stroke. The illegal addition of formaldehyde (FA) to extend the shelf life is a common problem reported in many countries and the FA is classified as a group 1 human carcinogen by the International Agency for Research on Cancer (IARC). There is also the natural formation pathway of FA in fish and seafood. This article summarises the FA levels in fish and seafood (from 2000), formation pathways, health risk assessment, regulations, and analytical techniques to measure FA. It is shown that the reported FA levels are frequently higher than the recognised safety level of 5 mg/kg. This review highlights the requirement of a broad scale effort to measure the indigenous FA levels in fish and ensure that this can be differentiated by the illegal addition of FA. This will allow the strengthening of regulations and allow monitoring to detect and deter the practice of illegal addition of FA to fish and seafood.

Rancang bangun smart nose pendeteksi zat pengawet berbahaya pada ikan

Fish is a source of protein that is widely consumed by indonesians, easy to obtain, and cheap. This foodstuff, quickly undergoes a process of decay caused by the growth of microorganisms, fish producers often use preservatives so that this product is not quickly damaged, especially preservatives that are not allowed formaldehyde. Therefore, a tool is needed that can easily detect the content of formaldehyde. We make a tool called smart nose that is a detection of harmful preservatives in fish. This research aims to create a smart nose tool design that can detect the content of formaldehyde in fish. The tools and materials used to assemble the components are the Arduino, jumper cable, HCHO sensor, LED, resistor, LCD and Bluetooth HC-05 module, as well as arduino IDE software to program the circuit. After the components are assembled, a smart nose tool is obtained that can detect the content of formaldehyde in PPM units.

PEMERIKSAAN KANDUNGAN ZAT KIMIA FORMALIN PADA BAKSO IKAN DAN TAHU

<p><em>Formaldehyde a toxic chemical compound. Formaldehyde is prohibited for use in food according to the RI Minister of Health Regulation No.033 of 2012 concerning food additives. Meatballs, Fish and Tofu are protein sources of food. This material is easily damaged by microorganisms. There have been many cases of formaldehyde found in food products in Indonesia. The purpose of this study was to determine the presence or absence of formaldehyde in fish, meatball and tofu before and after providing health education. the method used in this study is an experimental method using a Qualitative Analysis approach. The results obtained were found 16 samples (fish and dry fish) is positive of formaldehyde. after providing education to traders the 15 samples still found in the market. That means counselling is not effective as an effort to eliminate formaldehyde in food products.</em></p>

Characterization of Trimethylamin-N-Oxide Demethylase (TMAOase) of Lizardfish from Indonesian Waters

Formation of formaldehyde in fish can occur naturally through the breakdown of trimethylamine oxide (TMAO) become formaldehyde and the dimethylamine by-product in the fish during the postmortem phase by trimethylamine-N-oxide demethylase (TMAOase). The objective of this study was to characterize TMAOase which isolated from Saurida tumbil. The study was carried out by homogenizing of fish muscle using Tris-acetate buffer (pH 7.0) and centrifuged 10,000xg for 30 minutes. The supernatant was then added 1 M NaCl up to pH 4.5 and centrifuged at again. The supernatant was neutralized and heated at 80°C for 20 minutes, then centrifuged at 10,000xg for 30 minutes and then characterized by temperature, pH, cofactor effect on enzyme activity, and molecular weight. The same supernatant and then was dialyzed for 2 hours and determined its enzyme activity, protein concentration, and molecular weight. The result showed that TMAOase enzyme had optimum activity at pH 7 and temperature at 50°C and cofactor combination of cysteine, ascorbate, and FeCl2 could increase TMAOase activity. The dialysate had yield 3.71%, 1.78 fold purification, and molecular weight 20 kDa.

Risk Assessment of Kumasi Metropolis Population in Ghana through Consumption of Fish Contaminated with Formaldehyde.

This study evaluates the exposure of the Ghanaian population of the Kumasi Metropolis of Ghana to formaldehyde through the consumption of fish using 3-Methyl-2-Benzothiazoline Hydrazone method, with trichloroacetic acid as an extracting agent. A total of sixty (60) fish species comprising both local and imported fish were bought from cold stores and fish ponds were analysed. Formaldehyde was found in all the species analysed with concentration ranging from 0.174 to 3.710 μgg−1. However, the levels were still lower than 5 mg/kg, which is the maximum limit established by the Malaysian Food Act and Regulation for formaldehyde in fish. The estimated daily intake values for formaldehyde in the fish species analysed ranged between 4.233 × 10−4 and 3.661 × 10−3 mg/kg BW/day and this was less than the acceptable daily intake of 0.15 and 0.2 mg/kg BW/day suggested by World Health Organization and the United States Environmental Protection Agency for formaldehyde intake, respectively. The results for the hazard quotient calculated for all the species were less than one suggesting that the amount of formaldehyde in the fish is not likely to pose any potential adverse health effects to consumers. Thus, wet fish from Kumasi may be considered safe for consumption because of low formaldehyde content.

A biodegradable colorimetric film for rapid low-cost field determination of formaldehyde contamination by digital image colorimetry

A biodegradable colorimetric film was fabricated on the lid of portable tube for in-tube formaldehyde detection. Based on the entrapment of colorimetric reagents within a thin film of tapioca starch, the yellow reaction product was observed with formaldehyde. Intensity of the blue channel from the digital image of yellow product showed a linear relationship in the range of 0–25 mg L−1 with low detection limit of 0.7 ± 0.1 mg L−1. Inter-day precision of 0.61–3.10%RSD were obtained with less than 4.2% relative error from control samples. The developed method was applied for various food samples in Phuket and formaldehyde concentration range was non-detectable to 1.413 mg kg−1. The quantified concentrations of formaldehyde in fish and squid samples provided relative errors of −7.7% and +10.8% compared to spectrophotometry. This low cost sensor (∼0.04 USD/test) with digital image colorimetry was thus an effective alternative for formaldehyde detection in food sample.

Assessment of Formaldehyde Levels in Local and Imported Fresh Fish in Ghana: A Case Study in the Tamale Metropolis of Ghana

Fish is an important source of protein all over the world, including in Ghana. The fishery sector plays a major role in meeting the domestic need of animal protein and also contributes greatly in foreign exchange earnings. The domestic supply of fish does not meet the demand, so Ghana imports fish and fish products from other countries. Media reports in Ghana have alleged the use of formaldehyde to preserve fish for increased shelf life and to maintain freshness. This research, therefore, sought to establish the levels of formaldehyde in imported and local fresh fish in the Tamale Metropolis by using a ChemSee formaldehyde and formalin detection test kit. Positive and negative controls were performed by using various concentrations of formalin (1, 10, 30, 50, 100, and 300 ppm) and sterile distilled water, respectively. Three times over a 6-month period, different fish species were obtained from five wholesale cold stores (where fish are sold in cartons) and some local sales points (where locally caught fish are sold). A total of 32 samples were taken during three different sampling sessions: 23 imported fish (mackerel, herring, horse mackerel, salmon, and redfish) and 9 local tilapia. The fish were cut, and 50 g was weighed and blended with an equal volume (50 ml) of sterile distilled water. Samples were transferred to test tubes and centrifuged. A test strip was dipped into the supernatant and observed for a color change. A change in color from white to pink or purple indicated the presence of formaldehyde in fish. The study showed that no formaldehyde was present in the imported and local fish obtained. The appropriate regulatory agencies should carry out this study regularly to ensure that fish consumed in Ghana is safe for consumption.

A rapid liquid chromatography determination of free formaldehyde in cod

A rapid method for the determination of free formaldehyde in cod is described. It uses a simple water extraction of formaldehyde which is then derivatised with 2,4-dinitrophenylhydrazine (DNPH) to form a sensitive and specific chromophore for high-performance liquid chromatography (HPLC) detection. Although this formaldehyde derivative has been widely used in past tissue analysis, this paper describes an improved derivatisation procedure. The formation of the DNPH formaldehyde derivative has been shortened to 2 min and a stabilising buffer has been added to the derivative to increase its stability. The average recovery of free formaldehyde in spiked cod was 63% with an RSD of 15% over the range of 25–200 mg kg−1 (n = 48). The HPLC procedure described here was also compared to a commercial qualitative procedure – a swab test for the determination of free formaldehyde in fish. Several positive samples were compared by both methods.

Electrochemical Biosensor Immobilization of Formaldehyde Dehydrogenase with Nafion for Determination of Formaldehyde from Indian Mackerel (Rastrelliger kanagurta) Fish

An electrochemical biosensor was developed based on formaldehyde dehydrogenase immobilized with Nafion membrane for determination of formaldehyde in fish. The enzyme was immobilized through the entrapment technique and measured based on the reduction of I²-nicotinamide adenine dinucleotide. The response time of the formaldehyde biosensor was <1 min, with an optimum pH of 8. The optimum enzyme loading and NAD + concentrations were found at 30 mg/mL and 0.5 mM, respectively. Using the formaldehyde biosensor, a linear response of formaldehyde showed a range of 0.1 to 10 ppm and a detection limit of 0.016 ppm. In application of Nash method, the samples were stored at 4°C ± 1 for 10 days. With the two combined methods, a linear correlation coefficient with R ² = 0.9982 (y = 0.956x - 0.014) was found. The developed formaldehyde biosensor showed a good reproducibility, long storage stability (more than 6 months stored at 4°C), and also effective monitoring of formaldehyde level in Indian mackerel (Rastrelliger kanagurta) fish.