Essential and non-essential elements in Brazilian infant food and other rice-based products frequently consumed by children and celiac population

Rice and its derivatives are important source of essential and non-essential elements. Essential elements as cobalt (Co) and selenium (Se) are vital for human homeostasis. However, non-essential elements such as arsenic (As), cadmium (Cd) and lead (Pb) may be present in rice-based food and consequently, people can be exposed—especially children and the celiac population. This study aimed to determine essentials and non-essentials elements in rice-based products and baby food and also to evaluate nutritional risk by estimating the daily intake of non-essential elements. Regarding essential elements, Co and Se presented the highest concentrations in rice flour (56 μg kg⁻¹) and porridge (254 μg kg⁻¹), respectively. For non-essential elements, the highest concentrations of As, Cd and Pb were 104 μg kg⁻¹ (porridge), 16 μg kg⁻¹ (flour), and 188 μg kg⁻¹ (bread), respectively. Total As concentration in Brazilian rice-based baby food was <29 μg kg⁻¹. However, As-speciation revealed inorganic-As (i-As) as the main specie. The highest estimated daily intake of Cd, Pb and i-As were 1.37 (rice-based baby food); 10.39 (pasta); and 3.34 (pasta) μg d⁻¹, respectively. Therefore, continuous food monitoring for nutritional and toxicological purpose is necessary, especially concerning these particular populations and discussions for maximum levels of non-essential elements.     

Single-run analysis of vitamin D photoproducts in oyster mushroom (Pleurotus ostreatus) after UV-B treatment

A single-run high performance liquid chromatography (HPLC) with diode array detector (DAD) based method was developed for the separation, identification and comprehensive quantification of degradation products of ergosterol formed in oyster mushroom (Pleurotus ostreatus) after UV-B exposure. After 60 min, 10 substances involved in the photoprocess were separated, identified by their characteristic DAD spectrum and distinguished by their molecular weight, in cases where spectra were identical: vitamin D₂, previtamin D₂, tachysterol₂, lumisterol₂ and ergosterol, and, in minor quantity, their structural analogues of the 22,23-dihydroergocalciferol (vitamin D₄) series. Sample preparation protocol affected the total yields and the ratios of previtamin and vitamin D₂/D₄. Hot alkaline hydrolysis resulted in the best digestion of the mushroom matrix and accordingly gave the highest vitamin D yield (D₂: 141.32 μg g⁻¹ dry matter, DM; D₄: 22.72 μg g⁻¹ DM). Limit of detection for vitamin D_2/4 was 0.02 μg g⁻¹ dry matter (DM) and was estimated for previtamin D_2/4 (0.06 μg g⁻¹ DM), tachysterol_2/4 (0.02 μg g⁻¹ DM) and lumisterol_2/4 (0.06 μg g⁻¹ DM). Recovery of spiked vitamin D₂ was 97 ± 0.7%. The study provides an analytical tool to assess the process of vitamin D generation after UV-B treatment for the production of oyster mushrooms with a balanced nutritional profile of vitamin D compounds.     

Major and trace elements levels in multifloral and unifloral honeys in Croatia

Different honey types were collected in Croatia during 2010 and 2011: 7 multifloral orchard honeys, 7 multifloral meadow honeys, 19 black locust, 9 chestnut, 11 lime and 6 sage honeys. Elements were measured using graphite (As, Cu, Cd, Pb, Se) and flame atomic absorption spectrometer (Ca, Fe, K, Mg, Na, Zn) and by mercury analyser (Hg). Significant differences in Ca, Fe, K, Mg, Zn, As and Hg levels were observed between honey types. In chestnut honey were determined (K, Ca, Mg: mg kg⁻¹; Hg, Ad, Cd: μg kg⁻¹): the highest concentrations of K 2824.4, Ca 486.7, Mg 59.1 and Hg 2.52; the lowest of As 24.1 and Cd 2.52. Lime honey has been shown the highest content of Cu (20.6 mg kg⁻¹), Zn (6.78 mg kg⁻¹), Cd (2.14 μg kg⁻¹) and Pb (810.3 μg kg⁻¹). The lowest levels of following elements were determined in black locust honey (Fe, K, Mg: mg kg⁻¹; Hg: μg kg⁻¹): Fe 2.77, K 304.7, Mg 8.02 and Hg 0.82. Sage honey had the lowest Ca and Na content (173.9 and 31.8 mg kg⁻¹). Among the multifloral honeys, the following was determined (Fe, Na, Cu: mg kg⁻¹; As, Pb: μg kg⁻¹): orchard honey – highest of Fe 5.17 and As 276.1, lowest Pb 301; meadow honey – highest Na 36.1, lowest Cu 4.38. The average Ca, Cu and Pb levels found in multifloral honey types were much higher than those reported in other European countries. Calcium levels in lime, chestnut and black locust were higher than those from other countries.     

Evaluation of polycyclic aromatic hydrocarbons in Circassian cheese by high-performance liquid chromatography with fluorescence detection

Polycyclic aromatic hydrocarbons (PAH) in traditional/industrial smoked and unsmoked Circassian cheeses available in Turkish markets were analysed using solid-phase extraction, followed by high-performance liquid chromatography (HPLC) with fluorescence detection. Mean levels of a total of 9 PAHs in smoked traditional and industrial Circassian cheeses were 19.6 and 6.73 μg kg⁻¹, while levels in unsmoked traditional and industrial cheeses were 0.77 and 0.49 μg kg⁻¹, respectively. The dominant individual PAHs found were naphthalene and acenaphthene. Benzo[a]pyrene, a marker compound representing carcinogenic PAHs, was found in 90% and 30% of traditional smoked and unsmoked Circassian cheeses, 52% and 24% of industrial smoked and unsmoked cheeses, respectively. Correlation statistical analysis showed that benzo[a]pyrene was a good marker for total 9 PAHs in Circassian cheese samples (r_{B[a]P/sum of 9 PAHs} = 0.816, p < 0.01) as well as the best marker for 5 carcinogenic PAHs (r_{B[a]P/carcinogenic PAHs} = 0.904, p < 0.01). Risk assessment conducted using daily intakes of sum of 9 PAH levels found in both traditional and industrial smoked Circassian cheese samples showed high risk compared with unsmoked cheeses.     

Exposure assessment of arsenic speciation in different rice types depending on the cooking mode

Total (As_t), inorganic arsenic (As_i = As(III) + As(V)) and dimethylarsonic acid (DMA) were determined in 37 commercial rice samples collected in France. As_t was measured by inductively coupled plasma-mass spectrometry (ICP-MS) whereas anion-exchange chromatography – ICP-MS was used for As_i and DMA determination. As_t in raw rice varied from 0.041 to 0.535 mg kg⁻¹ whereas As_i varied from 0.025 mg kg⁻¹ (polished Basmati rice) up to 0.471 mg kg⁻¹ (organic rice duo). The daily intake and associated health risk for different population groups as a function of age and gender was also assessed. The intake varied between 0.002 and 0.184 μg kg⁻¹ body weight for As_t and 0.002 and 0.153 μg kg⁻¹ body weight for As_i, which do not pose a chronic toxicity risk. Organic wholegrain rice may entail a risk for children in the case of sole consumption at the expense of polished rice. The impact of rice cooking/boiling in terms of the overall toxicological risk related to As species was also investigated. Pre-rinsing and boiling the raw rice by using an excess of water is the most efficient mode to obtain a significant As_i removal and further reduction of the toxicological risk for children, particularly for white rice varieties.     

Fast method for the determination of copper,manganese and iron in seafood samples

A slurry sampling flame atomic absorption spectrometric method is proposed for the determination of copper, manganese and iron in oysters (Crassostrea rhizophora), clams (Anomalocardia brasiliana) and mussels (Mytella guiyanensis; Perna perna). Optimization was carried out using univariate methodology involving the following variables: nature and concentration of the acid solution for slurry preparation, sonication time and sample mass. The optimized conditions were 80 mg of sample ground in a cryogenic mil, dilution using 1.0 mol L⁻¹ nitric /hydrochloric acid solution, sonication time of 30 min and a slurry volume of 10 mL. The calibration curves had been prepared using standards of copper, manganese and iron also in 1.0 mol L⁻¹ nitric/hydrochloric acid solution. This method allowed the determination of copper, manganese and iron by FAAS, with detection limits of 0.17, 0.09 and 0.46 μg g⁻¹, respectively. The precision, expressed as relative standard deviation (RSD), are 3.0%, 2.9% and 3.8% (n=10), for concentrations of copper, manganese and iron of 17, 22 and 719 μg g⁻¹, respectively. The accuracy of the method was confirmed by analysis of the certified oyster tissue (NIST 1566b). The proposed method was applied for the determination of copper, manganese and iron in samples of oyster, clams and mussels, collected in Ubatuba and Todos os Santos Bay, Brazil. The obtained concentrations varied between 17.1 and 143.9 μg g⁻¹, 17.9 and 29.7 μg g⁻¹ and 364 and 1388 μg g⁻¹, respectively, for copper, manganese and iron. These values agree well with other data reported in the literature. The results showed no significant differences (P>0.005) using the proposed method with those obtained after complete digestion and determination by inductively coupled plasma-optical emission spectroscopy (ICP-OES).     

Genetic diversity of nutritionally important carotenoids in 94 pea and 121 chickpea accessions

Biofortification of staple crops via breeding is an attractive strategy for reducing human micronutrient deficiencies. The objective of this research was to examine the concentration of carotenoids in diverse pea and chickpea accessions grown in Saskatchewan (Canada) using high performance liquid chromatography. In pea accessions mean concentration of lutein was highest (11.2 μg g⁻¹) followed by β-carotene (0.5 μg g⁻¹), zeaxanthin (0.3 μg g⁻¹), and violaxanthin (0.3 μg g⁻¹). Green cotyledon pea accessions were richer in β-carotene and total carotenoids compared to yellow cotyledon accessions. In chickpea accessions mean concentration of lutein (8.2 μg g⁻¹) was highest followed by zeaxanthin (6.2 μg g⁻¹), β-carotene (0.5 μg g⁻¹), β-cryptoxanthin (0.1 μg g⁻¹), and violaxanthin (0.1 μg g⁻¹). Desi chickpea accessions had higher carotenoid concentration than kabuli accessions. This research identified pea and chickpea accessions that can be utilized in breeding for the improvement of carotenoid concentration through biofortification.     

Mineral composition and bioaccessibility in Sarcocornia ambigua using ICP-MS

This study evaluates the nutritional potential of Sarcocornia ambigua as new a source of minerals. The mineral concentrations of two different growing populations (natural occurrence and irrigated) of S. ambigua were evaluated using inductively coupled plasma mass spectrometry. In all samples, the mineral present in highest amounts was potassium (K) (19–24 μg g⁻¹), followed by magnesium (Mg) (8.6–14 μg g⁻¹) and then calcium (Ca) (2.6–4.0 μg g⁻¹). In addition, in vitro bioacessibility assay demonstrated that very high fraction (65–80%) of these K and Mg (80 and 65%) of total concentration of these elements is bioacessible from S. ambigua analyzed. The trace elements vanadium (V), chromium (Cr), cobalt (Co), copper (Cu) and lithium (Li) have more than above 50% of total concentration was found bioaccessible. In all cases, mass balance was verified by carrying out the total digestion of the remaining residue and the relationship between total concentration and bioaccessibility. The data related to the concentrations and the bioaccessible fractions of the minerals provide a starting point for more complex and in-depth evaluations from the nutritional point of view, including the establishment of a recommended daily dietary intake for this plant.     

An efficient,rapid and microwave-accelerated dispersive liquid–liquid microextraction method for extraction and pre-concentration of some organophosphorus pesticide residues from aqueous samples

In this paper, microwave-accelerated dispersive liquid–liquid microextraction has been developed for the extraction/preconcentration of some organophosphorus pesticides from aqueous samples prior to their analysis by gas chromatography–flame ionization detection. In this method, temperature of a high volume of aqueous sample is elevated by a microwave oven and then a mixture of extraction and disperser solvents is rapidly injected into the aqueous phase. After cooling to room temperature, the phase separation is accelerated by centrifuging. The main experimental factors affecting performance of the method including type and volume of the extraction and disperser solvents, temperature, pH, and salt addition were investigated and optimized. Under the optimum extraction conditions, the method resulted in low limits of detection and quantification within the ranges of 0.65–1.3 and 2.2–4.5 μg L⁻¹, respectively. Relative standard deviations were in the range of 2–7% (C = 40 or 100 μg L⁻¹) for intra-day (n = 6) and inter-day (n = 4) precisions. Finally, the proposed method was successfully applied to analysis of the target analytes in surface water and well water and fruit juice samples; diazinon was determined at μg L⁻¹ level in apple juice.     

Development of HPLC-DAD method for determination of neonicotinoids in honey

After the EU banned the use of the neonicotinoids in flowering crops that honeybees might visit, there has been an increased interest in determining the neonicotinoid residues in honeybee products such as honey. The aim of this study was to develop and optimize an HPLC-DAD analytical method with dispersive liquid–liquid microextraction (DLLME) and QuEChERS sample preparation procedures for the simultaneous analysis of seven neonicotinoids (dinotefuran, nitenpyram, thiametoxam, clothianidin, imidacloprid, acetamiprid and thiacloprid) in honey samples. The liquid chromatographic conditions were optimized by Response surface methodology with Box–Behnken design and Derringer's desirability. The optimized method was validated to fulfill the requirements of SANCO/12571/2013 standard for both sample pretreatment procedures providing results for accuracy (73.1–118.3%), repeatability (3.28–10.40%) and within-laboratory reproducibility (6.45–17.70%), limits of detection (1.5–2.5 μg kg⁻¹) and quantification (5.0–10.0 μg kg⁻¹) with the use of matrix-matched calibration to compensate the matrix effects. For the first time 104 honey samples from Vojvodina were analyzed. The presence of thiacloprid, imidacloprid and thiametoxam was found in a small number of samples implicating the usefulness of ongoing control of honey. Residues were confirmed by LC–MS/MS.     

Levels and sources of volatile organic compounds including carbonyls in indoor air of homes of Puertollano,the most industrialized city in central Iberian Peninsula. Estimation of health risk

Twenty nine organic air pollutants including carbonyl compounds, alkanes, aromatic hydrocarbons and terpenes were measured in the indoor environment of different houses together with the corresponding outdoor measurements in Puertollano, the most industrialized city in central Iberian Peninsula. VOCs were sampled during 8 weeks using Radiello^® passive samplers, and a questionnaire on potential VOCs sources was filled out by the occupants. The results show that formaldehyde and hexanal was the most abundant VOCs measured in indoor air, with a median concentration of 55.5 and 46.4 μg m⁻³, respectively followed by butanal (29.1 μg m⁻³), acetone (28.4 μg m⁻³) and acetaldehyde (21.4 μg m⁻³). After carbonyls, n-dodecane (13.1 μg m⁻³) and terpenes (α-pinene, 13.4 μg m⁻³ and limonene, 13.4 μg m⁻³) were the compounds with higher median concentrations. The indoor/outdoor (I/O) ratios demonstrated that sources in the indoor environment are prevailing for most of the investigated VOCs especially for limonene, α-pinene, hexanal, formaldehyde, pentanal, acetaldehyde, o-xylene, n-dodecane and acetone with I/O ratio >6. Multiple linear regressions were applied to investigate the indoor VOC determinants and Spearman correlation coefficients were used to establish common sources between VOCs. Finally, the lifetime cancer risk associated to formaldehyde, acetaldehyde and benzene exposure was estimated and they varied from 7.8 × 10⁻⁵ to 4.1 × 10⁻⁴ for formaldehyde, from 8.6 × 10⁻⁶ to 3.5 × 10⁻⁵ for acetaldehyde and from 2.0 × 10⁻⁶ to 1.5 × 10⁻⁵ for benzene. For formaldehyde, the attributed risk in most sampled homes was two orders of magnitude higher than the one (10⁻⁶) proposed as acceptable by risk management bodies.     

Proximate composition and lipid profile of red mullet (Mullus barbatus) from two sites of the Tyrrhenian and Adriatic seas (Italy): a seasonal differentiation

Proximate composition, unsaponifiable lipid components (cholesterol, squalene, tocopherols, all-trans retinol, total carotenoids) and fatty acid profile were evaluated on red mullet (Mullus barbatus) caught in the Central Tyrrhenian and Central Adriatic seas (Italy). The study was conducted in spring, the reproduction period, and in autumn, the period of maximum recruitment and market demand for this species. Results showed that, in fish from both sites, protein (18.1–18.8 g 100 g⁻¹), nonprotein nitrogen (0.32–0.35 g 100 g⁻¹), ash (1.27–1.42 g 100 g⁻¹) and cholesterol (56.8–73.7 mg 100 g⁻¹) contents were almost stable. Total lipid levels were highly variable, with very low levels in spring (0.96–1.48 g 100 g⁻¹) and high levels in autumn (7.28–8.72 g 100 g⁻¹). On a total fatty acids basis, polyunsaturated fatty acids (PUFA) were significantly higher in spring (30–40% of total fatty acids), when fish was lean, than in autumn (20%), while monounsaturated fatty acids were significantly higher in autumn (35–38%) than in spring (18–29%). Saturated fatty acids were almost stable throughout the year (34–39% of total fatty acids). Red mullet from the two sites showed a good nutritional value; in particular they proved to be a good source of n-3 PUFA, which accounted for 75–80% of total PUFA, regardless of the fishing season. However, it was in autumn that red mullet exhibited the highest content of n-3 PUFA (>1000 mg 100 g⁻¹ wet fillet). The comparison of samples by geographical origin showed no difference in autumn, while slight differences were observed in spring.     

A spectrophotometric method for determination of total proteins in cow milk powder samples using the o-nitrophenylfluorone/Mo(VI) complex

A new spectrophotometric method has been developed for the determination of protein in Tween 20 microemulsion medium. The method is based on the interaction between protein and o-nitrophenylfluorone–Mo(VI) complex as a spectral probe. Under the optimal conditions, Beer's Law is obeyed over the range of 0–16 μg mL⁻¹ bovine serum albumin (BSA) with the detection limit being 15 ng mL⁻¹. Both the influence of reaction variables and the interference of coexisting substance are studied. The proposed method has been applied to the whole milk powder samples with satisfactory results. The recoveries are between 97.6% and 105.8%, and the standard relative deviations are less than 4.3%. Molar ratio and slope ratio methods are used to determine the binding number of BSA with the complex and the value 96.     

Preliminary assessment of the nutritional composition of underexploited wild legumes from semi-arid Caatinga and moist forest environments of northeastern Brazil

The seeds of 14 wild legume species from Brazil were analyzed to assess their potential as food. The seeds showed high levels of crude protein (10.9–50.0%), dietary fiber (0.8–52.3%) and energy (905–1804 kJ 100 g^?1), and the amino acid composition (mg g^?1 N) was comparable to that of soybeans, but with higher amounts of lysine (456–10,884) and histidine (199–918). The seeds showed lectin activity (20–2560 and 60–2560 HU g^?1 flour for untreated or treated erythrocytes, respectively) as well as trypsin inhibitory activity (4.06–27.35 μg TI mg^?1 flour), urease (225–23,895 U kg^?1 flour) and toxic activities (LD₅₀ 0.22–0.12 g kg^?1 body weight). Most of the minerals, as with edible legume seeds, were present in high levels when considering reference daily intake (RDI) and the nutrient content claims of the United States Food and Drug Administration (FDA). Thus, these wild legume seeds can be promising alternatives sources of food to overcome malnutrition problems.     

Determination of nitrofuran metabolites in seafood by ultra high performance liquid chromatography coupled to triple quadrupole tandem mass spectrometry

A new analytical method has been developed for the simultaneous determination of 4 nitrofuran metabolites in seafood by ultra-high performance liquid chromatography coupled to triple quadrupole tandem mass spectrometry (UHPLC–QqQ-MS/MS). The extraction procedure was based on a simultaneous acidic hydrolysis and derivatization using 2-nitrobenzaldehyde (2-NBA), followed by a solid-phase extraction (SPE). Recovery was studied by spiking blank samples at two concentration levels (1 and 10 μg/kg) and recoveries ranged from 73 to 100% and 79 to 103%, respectively. Precision values, expressed as relative standard deviation (RSD) were ≤19% and ≤23% for intra-day and inter-day precision, respectively. Linearity was studied in the range 1–50 μg/kg and the obtained determination coefficients (R²) were ≥0.9900 for all compounds. Limits of detection (LODs) for the derivatized nitrofuran metabolites were 0.5–0.8 μg/kg and limits of quantification (LOQs) were established at 1 μg/kg, whereas decision limit (CC_α) and detection capability (CC_β) ranged from 1.5 to 2.6 μg/kg and 1.6 to 3.1 μg/kg, respectively. Finally, the method was applied to real food samples, but nitrofurans were not found.     

Assessment of hydroxymethylfurfural and furfural in commercial bakery products

A survey was conducted on the presence of hydroxymethylfurfural (HMF) and furfural in bread and bakery products; for this purpose a reliable extraction procedure followed by high performance liquid chromatography (HPLC) was applied. The performance of the method was evaluated in terms of linearity (r always > 0.99); detection limits (0.001 mg L⁻¹ for furfural and 0.006 mg L⁻¹ for HMF); recovery percentages (98.5–100.5% for HMF and 94.9–98.9% for furfural); intraday precision (<4.65%) and interday precision (<7.51%). Two batches of a wide variety of products commercially available were analysed (a total of 88 samples). HMF and furfural levels presented high variability between products and batches of the same product. Cake/pastry samples showed the lowest HMF content (3.0 mg kg⁻¹ fw) while biscuits showed the highest content (7.8 mg kg⁻¹ fw) (p < 0.05). Regarding furfural, bread samples presented the highest furfural content (5.3 mg kg⁻¹ fw) (p < 0.05), cake/pastry and biscuits showed the lowest content (1.9 and 3.0 mg kg⁻¹ fw, respectively). Chocolate containing samples presented higher amounts of furfural (>20 mg kg⁻¹). These results indicate that special attention should be given to furfural content of bread (due to its daily high consumption) and re-evaluation of dietary exposure.     

Protein fractions,amino acid composition and antinutritional constituents of high-yielding cowpea cultivars

High-yielding cowpea (Vigna unguiculata) cultivars were analysed for major changes in seed protein types, amino acid profiles and antinutritional factors content. As usual, the globulins constitute the major seed proteins (493.2–573.3 g kg^?1 total seed protein), followed by albumins (201.0–248.0 g kg^?1), basic glutelins (119.1–154.3 g kg^?1), acid glutelins (82.4–92.3 g kg^?1) and prolamins (13.2–20.2 g kg^?1). The electrophoretic patterns of seeds and protein fractions for all cowpea cultivars resembled to each other both qualitatively and quantitatively. However, they showed slight differences in the amino acid composition with common prevalence of glutamine/glutamic acid, asparagine/aspartic acid and phenylalanine + tyrosine. The methionine + cysteine contents were low for all cultivars and their protein fractions. Trypsin inhibitory activity varied among the cultivars and was much higher in the albumins (198.67–393.43 g kg^?1 protein). Haemagglutinating activity was also higher in the albumin fraction and varied from 30,900 to 444,400 HU kg^?1 flour. In conclusion, all cultivars showed the usual compositional characteristics of V. unguiculata, but the content of antinutritional factors differed among the cultivars although they remained concentrated in albumin and globulin fractions.     

Variability of biogenic amine and free amino acid concentrations in regionally produced goat milk cheeses

The free amino acid composition and biogenic amine content were analysed in pasteurised goat milk cheeses produced in different regions in Spain. These goat cheeses are made with pasteurised milk to which a mesophilic starter culture is added; they are enzymatically coagulated, uncooked, pressed cheeses. They have a firm texture with a slight but typical goat milk aroma and flavour. The total free amino acids varied markedly among the samples, ranging from 1400 to 28,000 mg kg⁻¹ DM (dry matter). Of the 20 amino acids analysed, the most abundant were leucine, proline, valine, glutamic acid, lysine, glutamine, ornithine and γ-aminobutyric acid, which accounted for over 60% of the total free amino acids. The goat milk cheeses presented low concentrations of biogenic amines, the most abundant being tyramine and/or histamine, with values ranging from 4.2 to 50.7 and from 10.2 to 60.5 mg kg⁻¹ DM, respectively. Total biogenic amine content ranged between 26.4 mg kg⁻¹ DM and 175.1 mg kg⁻¹ DM, and was always below the level that is considered dangerous for humans. Therefore, taking into consideration the concentrations of BAs, these goat milk cheeses, produced under good hygienic conditions, can be considered safe for consumers.     

Surveillance on chronic arsenic exposure in the Mekong River basin of Cambodia using different biomarkers

Thousands of Cambodia populations are currently at high risks of both toxic and carcinogenic effects through drinking arsenic-rich groundwater. In order to determine and assess the use of arsenic contents in different biological samples as biomarkers of chronic arsenic exposure from drinking arsenic-rich groundwater in Cambodia, individual scalp hair, fingernail and toenail were collected from three different provinces in the Mekong River basin of Cambodia. After washing and acid-digestion, digestate was analyzed for total arsenic by an inductively coupled plasma mass spectrometry. Chemical analysis of the acid-digested hair revealed that among 270 hair samples cut from Kandal, 78.1% had arsenic content in scalp hair (As_h) greater than the typical As_h (1.00 μg g⁻¹), indicating possible arsenic toxicity. Concurrently, 1.2% and 0.6% were found elevated in Kratie (n = 84) and Kampong Cham (n = 173), respectively. Similarly, the upper end of the ranges for arsenic contents in fingernail (As_fn) and toenail (As_tn) clipped from Kandal (fingernail n = 241; toenail n = 187) were higher than the normal arsenic content in nail (0.43–1.08 μg g⁻¹), however, none was observed elevated in both Kratie (fingernail n = 76, toenail n = 42) and Kampong Cham (fingernail n = 83; toenail n = 52). Significant positive intercorrelations between groundwater arsenic concentration (As_w), average daily dose (ADD) of arsenic, As_h, As_fn and As_tn suggest that As_h, As_fn and As_tn can be used as biomarkers of chronic arsenic exposure from drinking arsenic-rich groundwater, in which As_h is more favorable than As_fn and As_tn due to the ease of sample processing and analytical measurements, respectively.     

Short-term toxicity tests on the harpacticoid copepod Tisbe battagliai: Lethal and reproductive endpoints

Short-term bioassays based on lethal and reproductive responses of Tisbe battagliai were applied to determine responses of copepods to copper and LAS. Percentage of spawning females, fecundity (F), and total newborn production (N) for 48 and 72 h were calculated for both substances. It was observed percentage of spawning females was not affected by sublethal concentrations of both compounds. Following values were obtained: EC₅₀(N)-48 h of 670±30 μg LAS L^?1 and EC₅₀(F)-48 h of 670±30 μg LAS L^?1; and EC₅₀(N)-72 h of 44.5±1.8 μg Cu L^?1 and EC₅₀(F)-72 h of 30.8±1.1 μg Cu L^?1. Lethal effects of the two substance-types were also assessed, obtaining the LC₅₀-24 h of 1980±160 μg LAS L^?1; and LC₅₀-48 h of 83.1±10.5 μg Cu L^?1 for nauplii; and LC₅₀-72 h of 157±25 μg Cu L^?1, and LC₅₀-72 h of 2660±270 μg LAS L^?1 for adults. Fecundity and total newborn production are sensitive endpoints for determining effects of toxicants.