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Cereals and their derivatives are basic foods in the human diet and a source of minerals, but the content of elements may vary depending on the type of cereal or its processing. The levels of Na, K, Ca, Mg, Fe, Cu, Zn, Mo, Co, and Mn have been determined in 126 samples of cereals and cereal derivatives (rice, corn gofio, corn flour, wheat flour, corn, and wheat) commercialized and consumed in Cape Verde using an inductively coupled plasma-optical emission spectrometer (ICP-OES) after a wet microwave digestion process. Some elements stand out in products such as corn gofio (K), wheat (Mg), and wheat flour (Fe). Negative correlations were found between Mo-Na and Na-Zn that could suggest interference between these elements. Bearing in mind the dietary intake evaluation and the guideline values provided by EFSA (European Food Safety Authority) or FAO (Food Authority Organization), the consumption of wheat (100 g/day) provides a notable contribution of Mo, Mn, Fe, and Mg. Considering the nutritional value of the analyzed essential and trace elements, the consumption of different cereals and their derivatives should be promoted.

Cereals and cereal-based foods continue to be basic foods in all diets. Despite being known for their high nutritional value; they can also contain contaminants (hazards) such as toxic metals. This study assesses the Cd, Pb and Hg dietary exposure from cereals and derivatives marketed in Madeira and the Azores and characterizes the risks by evaluating the Cd and Hg intake contributions to the tolerable intakes and by estimating the Margin of Exposure (MOE) in the case of Pb. In Madeira, metals follow the descending order of Cd > Pb > Hg. Cd stands out as having the highest levels (0.307 mg Cd/kg in oats; 0.237 mg/kg in rye). High levels of Pb (0.347 mg/kg) were also detected in rye. Regarding total mercury, rice stands out (0.0013 mg/kg) followed by wheat (0.001 mg/kg). While all cereals and derivatives except maize consumed in Madeira exceed the maximum value of Cd allowed by the EU, 50.0% of the rye and 25.0% of the corn flour samples exceeded the European Pb limit. The daily consumption of 100 g of oats, rye flour and rye represent high contributions to the TWI of Cd (93.2 – 120%). The MOE values of Pb from the consumption of rye (100 g/day) are 1,294 (nephrotoxic effects) and 3,082 (cardiotoxic effects). In the Azores, corn flour (0.72 mg Pb/kg) stands out with 85.7% of the samples exceeding the maximum Pb EU limit and MOE values of 626 (nephrotoxic effects) and 1,490 (cardiotoxic effects). Regular daily consumption of corn flour makes a low (

Infertility has become more common, with an increased exposure to toxic compounds including heavy metals (HM). Follicular fluid (FF) surrounds the developing oocyte in the ovary and can be analysed to assess metal content. The levels of twenty-two metals were measured in the FF of ninety-three females in a reproduction unit, and their influence on assisted reproduction technique (ART), were examined. The metals were determined by optical emission spectrophotometry. Low values of copper, zinc, aluminium, and calcium favour polycystic ovary syndrome. The relationships between the number of oocytes and metals: iron (rs=0.303; p=0.003) and calcium (rs=−0.276; p=0.007) are significant, as well as between the number of mature oocytes with iron (rs=0.319; p=0.002), calcium (rs=−0.307; p=0.003) and sodium (rs=−0.215; p=0.039) and are near to significance in the case of aluminium (rs=−0.198; p=0.057). In the group with a fertilisation rate ≤ 75%, 36% of the women presented calcium >176.62 mg/kg compared to the group with a fertilisation rate ≥ 75% where this percentage was only 10% (p=0.011). An excess of iron and calcium reduces the good quality embryo rate, and an excess of potassium impairs the blastocyst rate. If potassium is above 237.18 mg/kg and calcium is below 147.32 mg/kg, these conditions favour embryo implantation. Pregnancy is influenced by high potassium and low copper levels. Controlling exposure to toxic elements is recommended for all couples with reduced fertility or receiving an ART.

This study investigated 20 elements in the muscle of 11 cephalopod species caught in the Canary Islands inhabiting from coastal to meso-bathypelagic habitats. Among them, trace element contents from large and elusive cephalopods such as Architeuthis dux, Taningia danae, Lepidoteuthis grimaldii, and Haliphron atlanticus were determined. Statistically significant differences in element concentration were found among class sizes and habitat. Large species that are inhabiting in deepest waters such as Loligo forbesii, A. dux, T. danae, H. atlanticus, and L. grimaldii showed a high load and variability in Fe and Al, while coastal species were characterized by a homogeneous element composition, being the Zn loads highest than other elements. Metal contents in large and elusive cephalopod species were dominated by Fe, Ni, Al, Zn, and Sr, with these species being able to carry important amounts of these elements to predators such as deep-diving odontocetes that reside around the Canary waters.

Potentially toxic elements (PTEs) (V, B, Ba, Li, Sr, Cr, Ni, Al, Pb, Cd) were determined in 130 samples of different tofu types (natural, flavoured, smoked and fresh made) by ICP-OES (inductively coupled plasma optical emission spectrometry). Al was the most notable element found with the highest concentration (6.71 mg/kg ww) found in flavoured tofu. Ni level (0.38 mg/kg) stands out in smoked tofu. European tofu has higher PTEs levels than Chinese tofu. Organic produced tofu has higher PTEs concentrations than conventional produced tofu. 200 g/day of smoked tofu confers a contribution percentage of 39.6% of its TDI (tolerable daily intake). In addition, 200 g/day of flavoured tofu would mean a high Pb contribution with a 23.2% of the BMDL (benchmark dose level) set in 0.63 µg/kg bw/day to the development of nephrotoxicity. Mean consumption would not pose a risk to adults’ health. Considering the obtained results, it would be advisable to establish limits for certain metals such as Pb, Al and Ni in this type of product. Furthermore, it is recommendable to set consumer guidelines to some tofu types in order to avoid excessive intake of PTEs.

Semen quality and levels of non-essential metals such as strontium (Sr), aluminum (Al), lead (Pb), nickel (Ni), and vanadium (V) were measured. Metals were determined by ICP-OES (inductively coupled plasma – optical emission spectrometry) in semen samples from 102 men who were recruited in a Reproduction Unit in the Canary Islands. The presence of each metal was as follows: Sr: 56.9%, Al: 73.5%, Pb: 45.1%, Ni: 15.7%, and V: 79.4% of the samples. No significant differences were found in the relationship between the spermiogram, the sperm motility, and the concentration of spermatozoa levels of non-essential metals. It is noteworthy that Ni levels tend to be lower in patients with oligozoospermia (t (46.4) = 1.84; p = 0.070). Between lifestyle and non-essential metals, there was a significant relationship between the level of occupational exposure to metals and Ni (χ2(2) = 13.91; p = 0.001). We did not find significant differences in non-essential seminal metal content and smoking status but, there were differences between drinkers and the concentration of V in semen (t (100) = −1.99; p = 0.050). The occupational exposure to metals and place of residence have effects on Al and V levels in semen. Regarding obesity, significant differences were found in Pb levels (t (18.0) = 2.34; p = 0.031). Obese patients have a lower Pb level, and the percentage of progressive sperm motility was lower in obese men (t (98) = 2.14; p = 0.035). The detection of metals in semen opens a new field in the study of male infertility with the possibility of performing treatments aimed at correcting these possible anomalies.

Spirulina is a multicellular cyanobacterium that is consumed as a dietary supplement. The content of trace elements (B, Ba, Li, Ni, Sr, V) and toxic metals (Al, Cd, Pb) was determined in 24 spirulina samples marketed in two different formulations (tablets and powder) by ICP-OES (inductively coupled plasma optical emission spectrometry). The highest element concentration was found in the powder presentation, except for Li. The powder presentation element levels (mg/kg dry weight) were Al (28.1), Sr (10.3), B (1.73), Li (1.47), Ba (1.25), Ni (0.63), Pb (88.1 μg/kg dw), Cd (37.2 μg/kg dw), and V (22.9 μg/kg dw). Considering an adult with a body weight of 68.48 kg and the posology guidelines (14 tablespoons per week), the consumption of powdered spirulina contributes greatly to the Al intake by 2.04% of its TWI (tolerable weekly intake) set at 1 mg/kg body weight/week, followed by Cd with 1.05% of its TWI set at 2.5 μg/kg bw/week. Pb intake represents 1.05% of the BMDL (benchmark dose) level associated with nephrotoxicity and 0.44% of the BMDL associated with cardiovascular effects. This assessment suggests that spirulina consumption does not pose risks to the consumer as far as exposure to toxic metals (Al, Cd, Pb) is concerned. However, the presence of trace elements and toxic metals in spirulina preparations should be monitored to ensure its quality and safety.

Water for human consumption is the main source of fluoride exposure. The concentration in water should not exceed 1 mg/L of fluoride since, at higher levels; it increases the risk of dental fluorosis, among other adverse effects. The fluoride content of 149 water samples from different aqueducts in Cauca (Colombia) has been determined by ion exchange chromatography with the aim of fluoride risk assessment. The rural area of the Municipality of Santander de Quilichao registered fluoride concentrations between 0.012 and 0.150 mg/L. The urban area of Santander de Quilichao recorded lower fluoride levels than the rural area (0.027-0.068 mg/L). The urban area of the Municipality of Cajibío registered fluoride levels of 0.082-0.186 mg/L. The highest levels of fluoride were found in Timbío (0.121-0.210 mg/L). The fluoride levels recorded in this study are not considered sufficient to trigger dental fluorosis. Likewise, optimal levels are not considered to protect the child population against dental caries. However, a monitoring plan of fluoride concentrations in water should be implemented to assure the quality and safe of the water.

Fluoride concentrations of 0.5 mg/L in drinking water are considered useful for dental caries prevention. However, fluoride concentrations higher than 1.2 mg/L in water can pose a risk of dental fluorosis due to high exposure to fluoride. The objective is to determine the fluoride concentration in water from aqueducts of different Colombian municipalities of Cauca (Popayán, Coconuco, and Puracé) to assess the fluoride dietary intake from the consumption of this water. A total of 66 water samples have been taken from Popayán, Coconuco, and Puracé. Fluoride content was determined by fluoride ion-selective electrode (ISE) potentiometry. The fluoride concentrations recorded in Coconuco and Puracé water were ≤ 0.002 mg/L. The mean fluoride content recorded in the Popayán water was 0.42 mg/L, with its highest concentration in Cauca River water (0.83 mg/L). Considering the admissible intake values, the water from Popayán confers remarkable fluoride intakes, especially in children with high percentages of contribution to the admissible daily intake (46.7% to 7- to 12-month children and 41.5% to 1- to 3-year children). The fluoride content in the water of Coconuco and Puracé does not reach an optimal value (

Fluoride is highly present in the environment, especially in water and its derivatives. Excessive fluoride contribution to diet poses a health risk. Tea leaves accumulate fluoride and the consumption of tea (Camellia sinensis) could pose a risk to human by the excessive fluoride intake. Ninety tea samples were analyzed by potentiometry using a selective fluoride ion electrode. Mixed tea samples (2.82 ± 1.11 mg/L) and black tea samples (2.28 ± 0.79 mg/L) recorded the highest fluoride levels. The contribution of drinking water is important for increasing fluoride levels in teas. The daily consumption of two cups (250 mL per cup) of mixed and black teas prepared with La Laguna tap water does pose a health risk for children (4–8 years old) because of the high contribution percentages (74.4% and 63.6%, respectively) of the Tolerable Upper Intake Level set in 2.5 mg/day by the EFSA (European Food Safety Authority). A minor consumption in children (4–8 years old) and adults during pregnancy is advisable.

Fluoride has been considered as the single factor most frequently responsible for causing enamel mottling. However, in humans, either endogenous and/or exogenous factors not related to fluoride exposure may also cause enamel mottling. In this sense, various studies in the international literature have reported severe mottling of the teeth that could not be attributed to fluoride exposure. Thus, misdiagnosis of non-fluoride-induced enamel defects may occur frequently. Reports of unexpectedly high population prevalence and individual cases of fluorosis, where such diagnoses are irreconcilable with the identified fluoride history, highlight the necessity for a more precise definition and diagnosis of dental fluorosis. Also, a more discriminating diagnostic procedure is suggested. Particularly, positive identification of environmental fluoride levels to which the communities and individuals are exposed shall be developed before the confirmation of a diagnosis of fluorosis. It is considered that a more critical methodology for the diagnosis of fluorosis will be helpful in the rational use and control of fluorides for dental health, and in the identification of factors that may induce enamel defects.

Fluoride is a widely distributed ion in the environment and, consequently, in water as well. High levels of fluoride in waters can be found in the Canary Islands because of their volcanic origin. Due to the risk and detrimental effects associated with a high fluoride intake, the content of this ion has been potentiometrically determined in 256 supply water samples from the islands of Tenerife, El Hierro, and La Palma, using a fluoride selective ion electrode. Fluoride mean concentration found on Tenerife is 4.22 mg/L, exceeding the parametric value of 1.5 mg/L set out in Spanish legislation. The consumption of 2 L of water from the studied municipalities of Tenerife would mean there is an excessive fluoride intake. The consumption of this water poses a serious risk to health. It is necessary to take action aimed at reducing the level of fluoride in the north of the island of Tenerife.

The increasing consumption of wakame algae (Undaria pinnatifida) and kombu (Laminaria ochroleuca) because of their culinary appeal and beneficial properties means there is a need to study the composition of these new foods. Algae stand out for their high iodine content, this being an essential element whenever it is ingested at recommended levels but which, ingested in high quantities, can cause harmful effects to health such as hyperthyroidism and even goiter. The iodine content in 30 samples of algae from different geographical origins (Asia and Europe) has been determined by oxidation-reduction titration with sodium thiosulfate. European kombu algae (27.7 ± 5.4 mg/kg dry weight) have the highest mean average iodine concentrations. European algae have higher iodine content than Asian algae. Significant differences (p

Seaweed consumption has increased considerably in Europe as a result of new trends in food. The macroelement (Na, Ca, K, Mg) and trace element (B, Ba, Co, Cr, Cu, Fe, Li, Mn, Mo, Ni, Sr, V, Zn) levels in different species of edible brown seaweeds were determined by inductively coupled plasma optical emission spectrometry (ICP-OES). European Himanthalia elongata species had the highest recorded concentrations of K (57480 mg/kg dry weight). Asian Undaria pinnatifida species had the highest Fe content (58.8 mg/kg dw). Five grams/day of dehydrated seaweed of the Asian U. pinnatifida species mainly contributes to the admissible daily intake of Mg (9.32% adults) and Na (7.05% adults). In any case which exceeds the maximum intake values of any of the elements analyzed, the macro- and trace element levels can vary considerably in a short period of time, so it is necessary to assess the toxic risk in edible seaweeds.

The levels of toxic metals (Al, Cd, Pb) and trace metals (B, Ba, Cu, Fe, Mn, Sr, Zn) were analyzed by inductively coupled plasma optical emission spectrometry (ICP-OES) in the muscle (sirloin and chuck) and liver from a total of 180 samples of steers (less than 2 years old) (Bos taurus) of foreign and local origin slaughtered on the island of La Palma (Canary Islands, Spain). As regards toxic metals, Al was the metal with the highest contents in both tissues of the foreign steers (3.75 mg/kg in the muscle and 55.3 mg/kg in the liver) and the local steers (5.60 mg/kg in the muscle and 8.65 mg/kg in the liver). In conclusion, the present study confirmed that beef is a source of trace elements, mainly Fe and Zn. In addition, the consumption of this type of beef did not show significant intakes of toxic metals (Al, Cd, and Pb) and, therefore, the consumption of the steer muscle and liver does not pose a toxicological risk for Spanish consumers.

The consumption of vegetable sausages or hamburgers is growing. The consumption of this type of product has increased exponentially in recent years for two main reasons: the rejection of meat consumption and the search for healthier foods. Vegetable sausages are relatively new products on the market and, as with other foods, they may contain trace elements, both essential and toxic. Thus, the objective of this work is the determination of the content of trace elements (B, Ba, Co, Cr, Cu, Fe, Li, Mn, Mo, Ni, Sr, V, Zn, Al, Cd, Pb) in 67 samples of vegetable sausages and burgers (27 samples of vegetable sausages and 39 samples of vegetable burgers) by means of ICP-OES (inductively coupled plasma optical emission spectrometry). The highest trace element levels were found in the sausage's samples, which remarkably are the Fe (14.1 mg/kg wet weight), Al (5.10 mg/kg ww), and Pb (0.05 mg/kg ww) content. Meanwhile, the levels of Zn (8.35 mg/kg ww), Mn (5.04 mg/kg ww), and Sr (2.77 mg/kg ww) were higher in burger's samples. The dietary exposure reveals that the consumption of 100 g/day of these products offers an important intake of Fe, Mn, and Cu. About the toxic trace elements, the consumption of the vegetable sausages (100 g/day) represents an intake of 14.6% of the TDI (tolerable daily intake) of Pb and sets in 0.5 μg/kg body weight/day. The consumption of 100 g/day of vegetable sausages and burgers does not pose a health risk. However, a higher consumption can carry a risk; for that reason, it is necessary to set a maximum level of certain elements in this kind of products.

This work presents the analysis of 20 heavy metals concentrations (Al, B, Ba, Ca, Cd, Co, Cr, Cu, Fe, K, Li, Mg, Mn, Mo, Na, Ni, Pb, Sr, V and Zn) in 80 muscle samples of two species widely consumed by humans, such as the European sardine (Sardina pilchardus) and the blue jack mackerel (Trachurus picturatus). Both species have similar metal concentrations, with significant differences in Ba, Ca, Ni, Pb and Mn. Most of the relations between the concentration of metals and the weight of the individuals were negative. All concentrations of toxic heavy metals were lower (than the legislated maximum limits for consumption S. pilchardus: 3.983 mg/kg Al, 0.016 mg/kg Cd, 0.047 mg/kg Pb, and T. picturatus: 5.484 mg/kg Al, 0.011 mg/kg Cd, 0.040 mg/kg Pb). The results were compared with available information with available information for the species. Higher metallic content found in studies from close areas of the African coast, could be due to the influence of the upwelling and to the dust from the the Saharan desert., Sí

Studies of the content of heavy metals and trace elements in fish and other marine organisms are of great importance to know the state of the marine ecosystem. This study has been carried out in northwestern African waters, Scomber colias being the target species, sampling a total of 345 specimens over 2 years. For the determination of metals and trace elements (Al, B, Cd, Cr, Cu, Fe, Li, Ni, Pb, V, and Zn) in the muscle, the ICP-OES (inductively coupled plasma optical emission spectrometry) was used. In the statistical study, the factors (oceanographic and maturity in the seasons, size of the specimens) were used. The samples sampled in the cold season that had high concentrations of metals may be due to the influence that African upwelling has on the Canary Islands. The metallic contents of our samples are lower than those found in the studies in Mauritania and Morocco due to the greater influence that upwelling has in these areas., Sí

Due to increased environmental pollution, monitoring of contaminants in the environment and marine organisms is a fundamental tool for assessing the existence of risk from their consumption to human health. The levels of toxic heavy metals (Cd, Pb, and Al), trace and essential metals (B, Ba, Co, Cu, Cr, Fe, Li, Mn, Mo, Ni, Sr, V, and Zn), and macronutrients (Ca, K, Mg, Na) in two species of fish for human consumption were quantified in the present study. Eighty samples of muscle tissue and 80 samples of liver tissue belonging to two species of Osteichthyes fish; Sarpa salpa and Chelon labrosus were analyzed. The studied specimens were caught on the northern coast of Gran Canaria (Canary Islands) with fishing rods. As they caught from the shore, they are suitable samples for assessing the toxic levels of representative species caught by local amateur fishermen. The results show that both species are fit for human consumption since they have toxic levels of heavy metals (Cd, Pb, and Al) which are below the maximum established levels; however, the toxic levels of the liver samples are several orders of magnitude higher than the muscle samples, so we discourage their regular consumption. The risk assessment indicated that the two species of fish are safe for the average consumer; however, if the livers of these species are consumed, there could be risks because they exceed the PTWI for Pb and the TWI for Cd.

Mushrooms are a valuable foodstuff because they are an important source of fiber and essential amino acids, but they have a great capacity to capture metals from substrate. Due to this reason, the content of 14 metals (B, Ba, Cr, Cu, Fe, Li, Mo, Ni, Sr, V, Zn, Al, Cd, Pb) of 100 samples of canned mushrooms grown in Spain were analyzed by inductively coupled plasma atomic emission spectroscopy. Fe (9.55 mg/kg) was the most notable trace element, followed by Zn (2.39 mg/kg). The most abundant toxic metal was Al (17.80 mg/kg). Significant statistical differences between the absorption of metals have been observed when comparing species. Lentinula edodes and Lactarius deliciosus are the species which had the highest metal contents. Taking the average consumption 300 g per day for adults into account, the exposure to trace toxic metals from the consumption of the studied mushrooms does not pose a health risk. However, contribution percentages of Pb (87.6%) and Al (59.2%) found in Lentinula edodes and Pholiota nameko samples, respectively, are near the maximum intake.

Sweet potatoes are a staple in the diet of some people and an excellent source of minerals. Metal monitoring in food, like sweet potatoes, provides basic information on safety aspects in regulatory processes as well as nutritional values. One hundred five samples of three varieties of sweet potatoes were randomly obtained from supermarkets, farmers markets, and farmers' plots in Tenerife (Canary Islands, Spain). The edible portion (pulp) was the only part considered for analysis. Flame atomic absorption spectrometry was used to determine the contents of sodium (Na), potassium (K), calcium (Ca), magnesium (Mg), copper (Cu), iron (Fe), manganese (Mn), and zinc (Zn), while the levels of chromium (Cr), nickel (Ni), cadmium (Cd), and lead (Pb) were determined using graphite furnace atomic absorption spectrometry. The mean concentrations were 500 Na, 4409 K, 564 Ca, 609 Mg, 1.291 Cu, 6.554 Fe, 2.324 Mn, 2.348 Zn, 0.028 Cr, 0.048 Ni, 0.001 Cd, and 0.003 Pb mg/kg, respectively. Potassium presented the highest contents in all varieties of sweet potatoes. Iron was the most abundant microelement. The orange fleshed sweet potato variety offered greater nutritional contributions to the recommended intakes than the rest of the varieties studied. The estimated mean daily intake of Ni (0.72 mg/day) detected in our samples was highly consistent with other studies. Average daily intakes of Cd (0.015 μg/day) and Pb (0.045 μg/day) were below toxicological reference values. In conclusion, the levels of Cd and Pb detected in the sweet potatoes analyzed do not represent any toxicological risk to consumers.

Trace metal concentrations (Fe, Cu, Co, Zn, Ni and V) were investigated in three rockpool shrimp species (Palaemon elegans, Palaemon adspersus and Palaemon serratus) from six littoral sampling sites (polluted and non-polluted) of Tenerife in the Canary Islands (Central Eastern Atlantic), Spain. Sex ratio for all three species has been determined: females predominate over males in all species and significant differences in total length and cephalothorax length was detected between sexes, being females larger than males. By other side, concentrations of trace metals were determined in whole specimens. Higher mean values for every metal were observed in P. adspersus. In males, higher values were observed in P. elegans and P. serratus, whereas in P. adspersus, mean values are higher in females. Finally, mean concentrations of trace metals studied were higher, in general terms, in the two clearly polluted stations: Santa Cruz of Tenerife commercial harbour and its fishery dock dependency.

The content of macroelements (Na, K, Ca, Mg and P) and microelements (Fe, Cu, Zn, Mn and B) in green and red pepper samples consumed on the island of Tenerife, Canary Islands, has been determined. Analysis has shown the influence of the ripening stage on the mineral content of the pepper. Red pepper presents higher K, Mg, P, Fe, Cu, Zn, Mn and B concentration levels than green pepper. There are differences between the values obtained in this study and the values shown in different food composition tables; our results are higher in Na, Ca and Mg, and lower in K and Fe.

Taros are a staple in the diet of many people around the world, and they are an excellent source of minerals. Monitoring the levels of metals in food provides basic information that is useful from the perspectives of safety, regulation, and nutrition. Forty-two samples of taros were randomly obtained from supermarkets, vegetable markets, and farmer's plots on the island of Tenerife (Canary Islands, Spain). The edible portion (pulp) was the only part considered for analysis. Flame atomic absorption spectrometry (FAAS) was used to determine the contents of Na, K, Ca, Mg, Cu, Fe, Mn, and Zn. The levels of Cr, Ni, Cd, and Pb were determined using graphite furnace atomic absorption spectrometry (GFAAS). Mean concentrations (mg/kg) were 565.6 Na, 2947 K, 231.4 Ca, 364.5 Mg, 1.224 Cu, 3.818 Fe, 1.408 Mn, 2.242 Zn, 0.044 Cr, 0.021 Ni, 0.003 Cd, and 0.006 Pb. The mean concentrations of Cd and Pb were well below the accepted European Commission limits (0.1 mg/kg weight for both metals, respectively). Daily consumption of taro (10.41 g taro/person/day) contributes to the dietary intake of essential metals and trace elements, mainly Mg (1.265% in adult women and 1.084% in adult men) and Cu (1.182% for adult men and women). The average daily intakes of Cd (0.031 μg/day) and Pb (0.062 μg/day) from taro were below the legislated respective tolerable weekly intakes (TWIs). Thus, the samples analyzed were considered safe to eat based on their metal concentrations and legislated allowable intakes.

The contents of macroelements (Na, K, Ca, Mg, and P) and microelements (Fe, Cu, Zn, Mn, and B) of four varieties of avocado obtained and consumed in the island of Tenerife, Canary Islands, have been determined. The samples mineral contents of the different avocado varieties showed significant differences. Thus, the concentration levels of Ca, Mg, and Mn are higher in the Hass variety; those of K, Fe, and Zn, in the Orotava variety; those of Na and B in the Hass and Fuerte varieties; that of P in the Arona and Hass varieties; and that of Cu in the Arona and Fuerte varieties. The area of origin of Hass avocado also influences the mineral content of the samples: those from the north of Tenerife show higher contents of K, Ca, P, Fe, Cu, Zn, and B, and those from the south, of Na, Mg, and Mn.

In this study we have determined the contents of macroelements (Na, K, Ca, Mg and P) and microelements (Fe, Cu, Zn, Mn and B) in papaya samples (Carica papaya) obtained and consumed on the island of Tenerife, Canary Islands. The analysis shows the existence of significant differences in mineral content in the papaya samples. The papaya coming from MercaTenerife (wholesaler) presents higher K, P and Mn concentration levels than the papaya coming from the South Area of Tenerife. On the other hand, Na concentration levels are higher in the samples coming from the South Area of the island. There are differences between the mineral contents of this fruit shown in some food composition data tables and those analyzed in this work. The former are lower in Na, K, Ca and higher in Fe. In the same way, it is appreciated that the levels of Na concentration found in this work are greater than those found by other authors, and lower in Fe. When we compare the results obtained in this work and the recommended daily intakes or daily estimated demands of mineral elements proposed by different institutions or authors we realize that papaya is an important source of certain mineral elements, mainly K, Mg and B.

The phytic acid content of hand-produced grain derivatives (gofio and frangollo) commonly consumed in the Canary Islands was determined. A total of 380 samples of gofio from different cereals (90 from wheat, 120 from corn, 60 from rye, 110 from barley) and 100 samples of frangollo were analyzed. The method proposed by Garcia-Villanova et al. in 1982 was used for determination of phytic acid content in cereal flours. Phytic acid concentrations are within the range >3–≥ 12 mg/g for gofio, and >3–≥ 9 mg/g for frangollo. The arithmetic means obtained from all the samples studied were 6.97 mg/g for gofio and 6.54 mg/g for frangollo. On analyzing the phytic acid content in all the gofio samples per cereal, significant differences were observed for the different gofio types. Corn gofio has a lower phytic acid content than rye and wheat gofios and a similar phytic acid content to barley gofio. There are no differences in phytic acid content among wheat, rye and barley gofios.

The analytical control of heavy metals in food is particularly important, since these pollutants are notably cumulative in nature and, therefore, can be toxic to humans. Their determination in foods of animal origin is of interest. In this study analyses of seven heavy metals in semipreserved ham and shoulder pork, preserved lunch pork and pork liver paste were performed to determine the possible influence of the container itself on the levels of metals in such products. Not only were the toxic elements cadmium and lead studied, but also copper, zinc, iron, nickel and manganese which, although not essentially toxic, could, in high concentration, cause public health hazards or a decrease in the organoleptic quality of the canned product, with resultant economic effect.

The main production of vinegar in Spain is wine vinegar. However, in the EEC countries as a whole the production is assorted (57% alcohol vinegar, 33% wine vinegar, 8% malt vinegar, 2% others). The inorganic ions in different types of vinegar (Na, K, Ca, Mg, Fe, Cu, and Zn) are normal constituents derived from the raw materials used in its production. The presence of toxic metals in vinegars can be derived from residues of agrochemical products, contamination from deteriorated metallic receptacles or environmental contamination. 12 refs., 1 fig., 3 tabs.

The presence of metallic pollutants in marine ecosystems has promoted wide research plans in order to evaluate pollution levels in marine organisms. However, little is known concerning environmental and physiological processes that regulate the concentration of trace metals in marine organisms. Even though the toxicity of lead and cadmium is well established, copper, zinc and iron are considered as essential elements for mammals. Little is known about heavy metals, other than mercury, concentrations in fresh and frozen tuna fish. Fifty samples obtained at the entrance of a canning factory in Santa Cruz de Tenerife (Canary Islands), were analyzed by atomic absorption spectrophotometry. Results were treated by applying the Statistical Package for the Social Sciences compiled and linked in the software of a Digital VAX/VMS 11/780 computer.