The influence of industrial-scale canning on cadmium and lead levels in sardines and anchovies from commercial fishing centres of the Mediterranean Sea

The current study encompassed a survey on the levels of toxic trace elements in two highly consumed fish species in commercial fishing centres of western, central and eastern Mediterranean Sea. A Zeeman GTA-AAS graphite furnace atomic absorption spectrometry system was used throughout the study. Toxicological evaluation of the samples revealed a low Cd content in the raw samples, ranging between 0.003 and 0.027?mg?kg^?1. Pb presented significantly higher values, from 0.037 to 0.297?mg?kg^?1, occasionally reaching the limit of 0.3?mg?kg^?1. Heavy metal levels were particularly higher in bones, thus raising queries about the safe consumption of fish intended to be eaten as a whole, a very common practice for small fish and canned products. The influence of industrial-scale canning showed that canning enhanced heavy metal levels by 35%–80%. The effect of canning depended on metal type and reduction of moisture loss after the steam-roasting step of the canning procedure.     

Biogenic amines assessment during different stages of the canning process of skipjack tuna (Katsuwonus pelamis)

The present research focused on the biogenic amines (BAs) formation in skipjack tuna (Katsuwonus pelamis) throughout the whole canning process. In agreement with its wide employment on this species, on‐board brine immersion freezing (BIF) was tested as post‐mortem processing. The study included fish samples corresponding to different stages of the canning process such as frozen, thawed, cooked and canned; after cooking, two kinds of tuna muscles were considered, that is, whole fillets (main product) and grated muscle (off‐product arising from small pieces). For the BAs (tryptamine, putrescine, cadaverine, histamine, spermidine and spermine) assessment, an HPLC‐DAD method was developed and validated in skipjack tuna samples, in agreement with different parameters such as suitability, linearity, limits of detection and quantification, precision, accuracy and robustness. Tuna submitted on‐board to BIF procedure provided low levels of spermine and spermidine (up to 27.6 mg kg^?1), while contents on the remaining BAs maintained below the limit of detection. Throughout the different stages of the canning process, skipjack tuna showed a low formation of most BAs; interestingly, histamine content was found below 10.6 mg kg^?1 level. The highest values were obtained for spermidine, these related to cooked grated tuna (from 22.6 to 66.7 mg kg^?1) and canned grated tuna (from 70.6 to 104.4 mg kg^?1). Values for pH assessment in all kinds of tuna samples corroborated the results obtained for BAs determination. BIF procedure proved to be an amenable post‐mortem processing to guarantee the quality of canned skipjack tuna.     

Survey and risk assessment of trace elements in foods from Taiwan containing red mould rice (Monascus) by ICP-MS

The concentrations of seven trace elements (As, Cd, Cr, Pb, Se, Cu and Zn) in 93 red mould rice (Monascus) food samples in Taipei, Taiwan, were determined by inductively coupled plasma-mass spectrometry (ICP-MS) after wet digestion. The results, calculated in mg?kg^?1 (wet weight) for each sample, revealed the general scenario of food safety in Taiwan: As (0.005–12.04), Cd (<0.0005–2.22), Cr (0.014–6.95), Cu (0.012–8.70), Pb (0.001–0.64), Se (<0.001–1.29) and Zn (0.020–67.02). Three food samples were identified with As concentrations higher than regulatory limits: a dietary supplement sample and a seaweed sample with As concentrations that exceeded the limit of Taiwan's health food standard of 2?mg?kg^?1, and a canned eel sample with an As concentration that exceeded the limit of Canada's fish standard of 3.5?mg?kg^?1. This study suggests that the estimated intakes of these seven trace elements from the consumption of foods containing Monascus pose little risk, as the trace element contents in the majority of samples were lower than the permissible/tolerable intakes per week according to the guidelines recommended by the Food and Agricultural Organization/World Health Organization (FAO/WHO). Moreover, their concentrations in foods containing Monascus differ widely for different food varieties, suggesting that external contaminants and raw materials are the main sources of trace elements. This study shows that ICP-MS is a simple method proposed for the determination of As, Cd, Cr, Pb, Se, Cu, and Zn in foods containing Monascus.     

Elemental composition of commercial sea cucumbers (holothurians)

Toxic and essential elements in 11 different sea cucumber species were determined and compared with daily intake recommendations and maximum allowed levels. The contents of macro-elements contents in dried sea cucumber samples were found to be 25,000–152,000?mg?kg^–1 for Na, 4000–8600?mg?kg^?1 for Mg, 1100–5200?mg?kg^?1 for K, 15,000–68,000?mg?kg^?1 and 36,300–251,000?mg?kg^?1 for Cl. Trace element concentrations in dried sea cucumber samples were found to be 11–100?mg?kg^?1 for Zn, 41–660?mg?kg^?1 for Fe, 3–74?mg?kg^?1 for Cu, 1.1–16?mg?kg^?1 for Mn, 1.4–3.7?mg?kg^?1 for Se, 1.1–9.6?mg?kg^?1 for Cr, and 0.3–5.1?mg?kg^?1 for Ni. All sea cucumber species were rich sources of Na, Cl, Mg, Ca, Fe, Cu, Se and Cr for human consumption. Regarding contaminants, As, Cd and Pb concentrations in dried sea cucumbers were in the ranges of 1.1–6.1, 0.03–0.06 and 0.11–0.69?mg?kg^?1, respectively. Moreover, Hg values of 11 sea cucumbers were below the detection limit (0.01?mg?kg^?1).     

Determination of the caffeine contents of various food items within the Austrian market and validation of a caffeine assessment tool (CAT)

The caffeine content of 124 products, including coffee, coffee-based beverages, energy drinks, tea, colas, yoghurt and chocolate, were determined using RP-HPLC with UV detection after solid-phase extraction. Highest concentrations of caffeine were found for coffee prepared from pads (755?mg?l^?1) and regular filtered coffee (659?mg?l^?1). The total caffeine content of coffee and chocolate-based beverages was between 15?mg?l^?1 in chocolate milk and 448?mg?l^?1 in canned ice coffee. For energy drinks the caffeine content varied in a range from 266 to 340?mg?l^?1. Caffeine concentrations in tea and ice teas were between 13 and 183?mg?l^?1. Coffee-flavoured yoghurts ranged from 33 to 48?mg?kg^?1. The caffeine concentration in chocolate and chocolate bars was between 17?mg?kg^?1 in whole milk chocolate and 551?mg?kg^?1 in a chocolate with coffee filling. A caffeine assessment tool was developed and validated by a 3-day dietary record (r ^2?=?0.817, p?<?0.01) using these analytical data and caffeine saliva concentrations (r ^2?=?0.427, p?<?0.01).     

Survey of the histamine content in fish samples randomly selected from the Greek retail market

The histamine content of fish sold in the Greek retail market was surveyed and the performance of high-performance liquid chromatography (HPLC) and enzyme-linked immunoabsorbant assay (ELISA) methods for the determination of histamine were compared. A total of 125 samples of fresh and canned tuna, fresh and canned sardines, deep frozen swordfish, smoked and deep frozen mackerel, anchovies, salted and smoked herring were analysed by HPLC (55 samples), ELISA (106 samples) and both methods (36 samples). Histamine levels as determined by HPLC, ranged from 2.7 mg kg^?1 to 220 mg kg^?1. The highest histamine concentrations obtained by HPLC were found in herring and anchovy samples. Eight out of the 55 samples (14.5%) analysed by HPLC, exceeded the US Food and Drug Administration (USFDA) limit (50 mg kg^?1), while 16 out of the 106 samples (15%) analysed by ELISA exceeded the limit. The results show that for histamine concentrations below 50 mg kg^?1, there is good agreement between the ELISA and HPLC but above 50 mg kg^?1 big differences were found.     

Trace elements in edible tissues of three shrimp species (Penaeus semisulcatus,Parapenaeus longirostris and Paleomon serratus)

Accumulation levels of trace elements in edible tissues of three shrimp species (Penaeus semisulcatus, Parapenaeus longirostris and Paleomon serratus) from the Gulf of Antalya, Turkey were investigated. Copper (Cu), cadmium (Cd), zinc (Zn), iron (Fe) and manganese (Mn) concentrations were determined by atomic absorption spectrophotometry. The lowest Cu (1.33 mg kg^?1) and Cd (0.23 mg kg^?1) and highest Mn (1.52 mg kg^?1) concentrations were found in P. longirostris, the lowest Zn (6.25 mg kg^?1), Fe (1.84 mg kg^?1) and Mn (0.25 mg kg^?1) concentrations in P. serratus and the highest Cu (6.19 mg kg^?1), Cd (2.36 mg kg^?1), Zn (30.84 mg kg^?1) and Fe (33.89 mg kg^?1) concentrations in P. semisulcatus. The Cd levels detected in P. semisulcatus and P. serratus were above legislative limits. Our results show that there were significant differences in trace element concentrations among the three shrimp species. The highest levels of the five trace elements investigated, with the exception of Mn, were found in edible tissue of P. semisulcatus. Copyright © 2007 Society of Chemical Industry     

Toxic (Pb,Cd, Hg) and essential (Fe,Cu, Zn,Mn) metal content of liver tissue of some domestic and bush animals in Ghana

Accumulation of toxic metals in liver, a rich natural source of essential elements, can present health risks to regular consumers of liver. A total of 35 fresh liver samples of cow, sheep, goat, pig, grass-cutter (Thryonomys swinderianus), gaint rat (Cricetomys gambianus), red deer (Cervus elaphus), chicken and antelope (Antilocapra americana) were obtained from three different markets in Accra and Kumasi, Ghana. Samples were analyzed using atomic absorption spectrometry and an automatic mercury analyzer. Levels of iron in the grass-cutter and pig of 500.5–645.4 mg kg^?1 were the highest in the animal livers examined. Mn concentrations were highest in grass-cutter and rat liver, ranging 16.5–30.2 mg kg^?1. The safe Cu and Zn permissible limits of 20 and 50 mg kg^?1 were exceeded in 70 and 75% of the liver samples, respectively. Generally, for each animal group studied, at least 50% of the sample livers exceeded the Cd permissible limit of 0.5 mg kg^?1. The levels of Pb, which ranged 1.3–13.8 mg kg^?1, exceeded the proposed European Commission (EC) limit of 0.5 mg kg^?1. Care must be taken by regular consumers of the iron-rich animal livers of grass-cutter, pig and rat because they also had the highest levels of Pb (in grass-cutter and pig) and Cd (in grass-cutter, rat and pig). The liver samples analyzed for Hg had values far below the permissible limit of 0.5 mg kg^?1.     

Soil and vegetable compositional relationships of eight potentially toxic metals in urban garden fields from northern Nigeria

BACKGROUND: Human exposure to heavy metals is attributed to consumption of vegetables raised in polluted soil environment. We examined the concentrations of As, Cd, Co, Cr, Cu, Ni, Pb and Zn in soils and lettuce (Latuca sativa) and amaranthus (Amaranthus caudatus) in 15 garden fields under long‐term wastewater irrigation. RESULTS: The concentrations of As (0.3–2.1 mg kg^?1), Cd (0.07–0.3 mg kg^?1), Co (4.6–9.1 mg kg^?1) and Cr (21.6–36.2 mg kg^?1) in the gardens were consistent with background concentrations in soils, but Ni (12.6–25.7 mg kg^?1), Cu (12.5–24.6 mg kg^?1), Pb (25.7–71.6 mg kg^?1) and Zn (52.3–158 mg kg^?1) concentrations were double the concentrations normally encountered in arable fields in the region. The concentrations of Cd and As in the vegetables were within safe limits, but Co (0.14–0.67 mg kg^?1 fresh weight (fw)) and Ni (1.0–2.7 mg kg^?1 fw) concentrations in lettuce were relatively high for leaf vegetables. The concentration of Pb (0.65–4.80 mg kg^?1 fw) was above safe limit of 0.3 mg kg^?1 fw, while the concentrations of Cu (1.3–2.7 mg kg^?1 fw and Zn (10.2–23.6 mg kg^?1 fw) were close to the unsafe limits for leaf vegetables. There were no strong linear correlations between soil metal concentrations and bio‐concentrations in the vegetable crops. CONCLUSION: We surmise that leaf vegetables can accumulate metals in their tissues to unsafe levels even when total metal concentrations in these soils are below the allowable concentrations in agricultural soils. Copyright © 2008 Society of Chemical Industry     

Effect of thermal processing and canning on cadmium and lead levels in California market squid: the role of metallothioneins

The effects of two common seafood preparation practices (roasting and industrial canning) on the heavy metal content – cadmium (Cd) and lead (Pb) – of various tissues of California market squid were studied. Emphasis was placed on the role of metallothioneins (MT) in Cd and Pb behaviour during processing. Cd and Pb analysis was conducted by a Zeeman GTA-AAS atomic absorption spectrometry system; MT analysis was performed by a mercury saturation assay. Results showed that Cd levels in the mantle and whole squid were considerably affected by both processing practices, reaching a 240% increase in mantle and a 40% increase in whole squid. Interestingly, Cd behaviour was associated with MT changes during squid processing. On the other hand, Pb content was not affected from either processing or associated with MT content in the raw or processed squid. Therefore, processing operations may affect Cd and Pb content differently due to the specific metal bioaccumulation and chemical features of each heavy metal type.     

Variations in cadmium accumulation among rice cultivars and types and the selection of cultivars for reducing cadmium in the diet

A pot trial was conducted with 52 rice cultivars of different types collected from different origins. The results showed that there were great differences in Cd concentrations in straw, brown rice and grain chaff among the rice cultivars grown in a soil containing a Cd concentration of 100 mg kg^?1; the Cd concentrations in brown rice ranged from 0.22 to 2.86 mg kg^?1. The great genotypic differences in Cd concentrations indicated that it is possible to lower the Cd content of rice through cultivar selection and breeding. Significant differences were found in the Cd concentrations of the rice types of Indica consanguinity and those of Japonica consanguinity, but not between their origins. There were significant correlations between straw and brown rice in Cd concentration and in the total amount of Cd accumulated. The distribution ratios of the Cd accumulated in brown rice to the total Cd accumulation in the above‐ground rice plant varied greatly from 12.9 to 137.8 g kg^?1, and there was significant correlation between the distribution ratios and Cd concentrations in brown rice. These indicated that Cd concentration in rice grain is governed by the transport of Cd from root to shoot and also from shoot to grain. Cd concentrations in brown rice also correlated significantly with some important agronomic traits, as well as with nitrogen concentrations, one of the most important criteria for rice quality. Copyright © 2004 Society of Chemical Industry     

Determination of 2,6-diisopropylnaphthalene (DIPN) and n-dibutylphthalate (DBP) in food and paper packaging materials from US marketplaces

A gas chromatography-ion-trap tandem mass spectrometry procedure was developed for the determination of 2,6-diisopropylnaphthalene (DIPN) and n-dibutylphthalate (DBP) in domestic and imported paper packages and food sold in US marketplaces. The procedure involved ultrasonic extraction with dichloromethane, followed by analysis with the gas chromatography-ion-trap tandem mass spectrometry. Calibration curves for DIPN and DBP were achieved with concentrations ranging from 0.01 to 10 µg ml^?1 and the corresponding r ² values were 0.9976 and 0.9956, respectively. In most of the fortified samples the recoveries were higher than 80% with a relative standard deviation (RSD) <10%. Using this procedure, it was found that less than 20% of the tested domestic packages and more than 60% of the tested imported food packages contained both DIPN and DBP. The concentrations of DIPN and DBP ranged from 0.09 to 20 mg kg^?1 and 0.14 to 55 mg kg^?1, respectively, with most of the DINP and DBP levels lower than 20 mg kg^?1. DIPN was not detected (<0.01 mg kg^?1) in 41 food samples and DBP was only detected in two domestic and four imported food samples with concentrations ranging from <0.01 to 0.81 mg kg^?1.     

Essential elements and contaminants in tissues of commercial pelagic fish from the Eastern Mediterranean Sea

BACKGROUND: It is important to determine the concentrations of essential and non‐essential metals in fish for human health. The essential elements and contaminants (Pb and Cd) were determined seasonally in the muscle and liver of some pelagic fish species round herring (Etrumeus teres), chub mackerel (Scomber japonicus), golden grey mullet (Liza aurata) and Mediterranean horse mackerel (Trachurus mediterraneus) from the Iskenderun Bay, Eastern Mediterranean Sea. RESULTS: The Na, K, Ca and Mg were the most abundant elements in muscle and liver tissues. The Na, K, Ca and Mg concentrations in fish tissues were between 51.7 and 3426 mg kg^?1. Muscle accumulated the lowest levels of elements. Trace element and contaminant levels in muscle were highest in spring and summer. The Cu, Zn and Cr concentrations were highest in summer. The Ni, Mn and Fe concentrations were highest in spring. The maximum Pb concentrations in the muscle and liver of fish species was 0.39 and 0.80 mg kg^?1 in autumn. The maximum Cd concentration in the muscle of fish was 0.27 mg kg^?1 in spring and the maximum Cd concentration in the liver was 0.78 mg kg^?1 in summer. CONCLUSION: The Cr, Pb, Cd, Cu and Zn levels in muscle were found to be lower than permissible limits reported by various authorities. Estimated weekly and daily intake for Pb and Cd by consumption of fish muscle were far below the PTWI and PTDI values established by FAO/WHO. Copyright © 2009 Society of Chemical Industry     

Survey of iron,zinc, calcium,copper, lead,and cadmium in rice samples grown in Iran

In the present study ninety nine polished white rice samples were collected in three areas, all over Lorestan Province located in the west of Iran, and analysed for six elements by Flame Atomic Absorption Spectrometry (FAAS). For individual elements, Zinc (Zn) showed the highest concentration among the analysed essential elements with a mean of 28.6 mg kg^?1 and next to copper (Cu) of 22.8 mg kg^?1. Analysis of the essential and toxic elements for possible inter-area variation by ANOVA showed that there are significant differences between the areas. There was no significant difference between areas for Zn concentrations. Most of the samples nearly contained world wide average concentration of iron (Fe) and Zn in rice grains that were reported by various researches. But, the content of calcium (Ca) in the rice samples produced in Lorestan Province were much lower than other countries, meanwhile Cu concentrations were much higher than other studies. Cadmium (Cd) and Lead (Pb) concentrations in the sampled rice were lower in comparison with their upper limits (0.1 and 0.2 mg kg^?1 for Cd and Pb, respectively) approved by Iranian Ministry of Health. Therefore, it can be concluded that there is no health problems result from Lorestan rice consumption, for these two elements.     

Evaluation of table olive by‐product as a source of natural antioxidants

The main by‐product from the table olive canning industry is the stone with some residual olive flesh. The purpose of this study was to evaluate the composition – phenolic compounds (hydroxytyrosol, tyrosol and oleuropein) and tocopherol – and the antioxidant activity in different fractions (flesh, stone and seed) from the table olive by‐product and the whole by‐product. The highest amounts of phenolic compounds (1710.0 ± 33.8 mg kg^?1) as well as the highest antioxidant activity (8226.9 ± 9.9 hydroxytyrosol equivalents mg kg^?1) were obtained in the seed. The highest amounts of hydroxytyrosol (854.8 ± 66.0 mg kg^?1) and tyrosol (423.6 ± 56.9 mg kg^?1) were found in the whole by‐product from the pepper stuffed olives, while the stone without seed had the maximum oleuropein content (750.2 ± 85.3 mg kg^?1). α‐Tocopherol values were between 79.8 ± 20.8 mg kg^?1 in the seed of the olive stone and 6.2 ± 1.2 mg kg^?1 in the whole by‐product from the anchovy‐stuffed olives. In light of the results obtained, it would seem possible to use table olive by‐product as a source of natural antioxidants in foods, cosmetics or pharmaceutical products, thus contributing to diminishing the environmental impact of table olive by‐product and to its revalorisation.     

Furan in canned sardines and other fish

Thirty-seven different samples of canned sardines and other fish sold in the United Kingdom were analysed for their furan content using a validated automated headspace gas chromatography–mass spectrometry procedure. All 37 samples contained detectable furan, with an average level of 26 μg kg^?1. The maximum furan content was in canned fish containing tomato sauce, which had an average of 49 μg kg^?1 and in canned fish packed with lemon which had an average of 55 μg kg^?1. All fish in brine or in oil contained less than 20 μg kg^?1 furan. Furan levels recorded in fish packed in extra virgin olive oil were low with an average of 2 μg kg^?1.     

Determination of phthalates in raw bovine milk by gas chromatography/time-of-flight mass spectrometry (GC/TOF-MS) and dietary intakes

Low levels of phthalates, including di(2-ethylhexyl) phthalate (DEHP), in raw bovine milk were determined using gas chromatography/time-of-flight mass spectrometry (GC/TOF-MS). A fast and convenient process of sample treatment combined with TOF-MS analysis (medium resolution >5000), yielded good recoveries (85–125%) and low limits of detection (<0.002 mg kg^?1). The most commonly used phthalate, DEHP, was found in 15 out of 30 samples monitored in this study. DEHP concentrations in raw milk ranged from not detected to 0.154 mg kg^?1, and the mean concentration was 0.057 mg kg^?1. The dietary intake of DEHP was about 0.004 mg kg^?1 body weight day^?1 if a child (24 months, 13 kg body weight) drinks 1 L day^?1 of milk that contains the mean concentration of DEHP found in raw milk. The estimated dietary intake corresponded to 8% of the European Union tolerable daily intake (TDI) of 0.05 mg kg^?1 body weight day^?1. Dimethyl phthalate (DMP) and di-n-butyl phthalate (DBP) were found from two and 20 samples, respectively, at low levels. Diethyl phthalate (DEP), butylbenzyl phthalate (BBP), and di-n-octyl phthalate (DnOP) were not found in any of the samples.     

Analysis and risk assessment of arsenic,cadmium and lead in two fish species (Sardina pilchardus and Xiphias gladius) from Algerian coastal water

ABSTRACT

In this study, the levels of arsenic (As), cadmium (Cd) and lead (Pb) have been determined in the flesh of two species of fish, sardine (Sardina pilchardus) and swordfish (Xiphias gladius) fished in the Algerian coast. Quantification of As, Cd and Pb was carried out using an ICP-MS method and the results were compared with the thresholds set by national and international regulatory bodies. In a further step, the risk to consumers was assessed using estimated daily intake (EDI), target hazard quotient (THQ) and hazard index (HI).The average concentration of As and Pb was higher in sardine (1.82; 0.10 mg kg^?1 w.w., respectively), than in swordfish (1.10 mg kg^?1 w.w.; not determined), whereas the concentration recorded for Cd was the same for both species (0.01 mg kg^?1 w.w.). These concentrations are below maximum limits set in regulations. The THQs and HI were widely below 1. The consumption of these fish does not pose risk to the consumers.     

Elemental composition of cephalopods from Portuguese continental waters

Essential and contaminant elements concentrations were determined in the muscle tissue of octopus (Octopus vulgaris), squid (Loligo vulgaris) and cuttlefish (Sepia officinalis), caught off the Portuguese coast in 2004–2005. As expected, the largest concentrations found correspond to Cl, S, K, Na, P and Mg (average values between 629 mg (100 g)⁻¹, for Cl, and 435 mg kg⁻¹, for Mg, in octopus and squid, respectively). Above average concentrations of Zn, Cu, Fe and Sr were also found. The highest total Hg concentration was found in cuttlefish (0.36 mg kg⁻¹); however, this value did not exceed the recommended limit proposed by EU (0.5 mg kg⁻¹). Lead levels observed in all samples were always significantly lower than the EU limit (1.0 mg kg⁻¹). Regarding Cd, the 1.0 mg kg⁻¹ limit was only exceeded in two octopus samples. It may be concluded that the cephalopods studied do not constitute cause for concern, in terms of toxic elements, and could be safely used for daily intake of essential elements. Nevertheless, the squid contribution for elemental DI is minor in comparison to the other two species.     

CHARACTERIZATION OF SURFACE AUXIN RESIDUE IN GREENHOUSE TOMATOES (LYCOPERSICON ESCULENTUM)

Greenhouse tomato samples (n = 20) was analyzed before and after peel removal in order to determine surface auxin residue. Mean 4‐CPA residue levels of greenhouse tomatoes with and without peels were 0.383 ± 0.123 mg kg^?1 and 0.241 ±0.085 mg kg^?1, respectively. This difference (36 ±13%) was statistically significant. The frequency distribution curve of tomatoes with peel had a peak point at 4‐CPA reside interval of 0.4‐ < 0.5 mg kg^?1 tomato, and shifted back to 4‐CPA residue interval of 0.2‐ < 0.3 mg kg^?1 for tomatoes without peel. Percentage of samples having 4‐CPA level lower than the critical concentration of 0.5 mg kg^?1 was 80% before peel removal, but increased to 100% upon being peeled. The mean 4‐CPA residue of peels was roughly estimated to be 3.449 mg kg^?1 peel based on peeled versus nonpeeled fruit residue.