Aflatoxin B1 in betel nuts (Areca catechu L.) imported to Pakistan from different regions of South Asia

Aflatoxin B₁ (AFB₁) levels were evaluated in betel nuts (Areca catechu L.) being imported to Pakistan during 2010–2011. In total, 278 betel nut samples (India = 21, Indonesia = 51, Sri-Lanka = 34 and Thailand = 172) were received from the Department of Customs and were analysed by thin layer chromatography (TLC). All Indian origin betel nuts showed AFB₁ contamination ranging from 11.7–262.0 µg kg^?1 with a mean of 92.5 µg kg^?1. Among Indonesian and Sri Lankan shipments, 80.4% and 73.5% betel nuts were contaminated with AFB₁ ranging between 3.3–39.2 and 6.5–103.4 µg kg^?1 with a mean of 11.6 and 35.0 µg kg^?1, respectively. However, only 30.2% of Thailand origin samples showed AFB₁ contamination ranging 3.3–77.0 µg kg^?1 with a mean of 6.6 µg kg^?1. The widespread occurrence of AFB₁ increases the hazard associated with betel nuts. Thus, strict control is a pre-requisite for the production and import/export of psychoactive substances as betel nuts.     

Dietary exposure of Hong Kong adults to fatty acid esters of 3-monochloropropane-1,2-diol

A total of 290 individual food samples were collected in Hong Kong, China, for 3-monochloropropane-1,2-diol (3-MCPD) fatty acid esters analysis. Most samples were processed food and in ready-to-eat form. The results show that the levels of 3-MCPD fatty acid esters were high in biscuits, fats and oils, snacks and Chinese pastry with mean bound 3-MCPD levels of 440, 390, 270 and 270 μg kg^?1, respectively. The dietary exposures to bound 3-MCPD of average and high adult consumers were estimated to be 0.20 and 0.53 μg kg bw^?1 day^?1, respectively. The primary toxicological concern of 3-MCPD fatty acid esters is its potential to release 3-MCPD in vivo during digestion in the gastrointestinal tract. 3-MCPD would affect the kidney, the central nervous system and the male reproductive system of rats. Assuming that 100% of the 3-MCPD was released from 3-MCPD fatty acid esters by hydrolysis in the digestive system, the dietary exposures to 3-MCPD for average and high adult consumers were only 10% and 26% of the provisional maximum tolerable daily intake (PMTDI) of 3-MCPD established by the Joint Food and Agriculture Organization/World Health Organization Expert Committee on Food Additives (JECFA) (2 μg kg bw^?1 day^?1), respectively. The results suggest that both average and high adult consumers are unlikely to experience major toxicological effects of 3-MCPD.     

Investigation of pyrrolizidine alkaloids including their respective N-oxides in selected food products available in Hong Kong by liquid chromatography electrospray ionisation mass spectrometry

ABSTRACT

This study determined the levels of pyrrolizidine alkaloids (PAs), including their respective N-oxides, in foodstuffs available in Hong Kong by liquid chromatography-electrospray ionisation tandem mass spectrometry. A total of 234 samples (48 food items) were collected randomly from a local market and analysed. About 50% of samples were found to contain detectable amount of PAs. Amongst the 48 food items, PAs were not detected in 11 food items, including barley flour, beef, cattle liver, pork, pig liver, chicken meat, chicken liver, milk, non-fermented tea, Melissa tea and linden tea. For those found to contain detectable PAs, the summed PA content ranged up to 11,000 µg kg^?1. The highest sum of PA content among the 37 food items calculated with lower bound was cumin seed, then followed by oregano, tarragon and herbs de Provence with ranges of 2.5–11,000, 1.5–5100, 8.0–3300 and 18–1300 µg kg^?1 respectively. Among the samples, the highest sum of PA content was detected in a cumin seed sample (11,000 µg kg^?1), followed by an oregano (5100 µg kg^?1), a tarragon (3300 µg kg^?1) and a herbs de Provence (1300 µg kg^?1). In general, the results of this study agreed well with other published results in peer-reviewed journals, except that the total PAs in honey and specific tea infusion in this study were comparatively lower.     

3-Monochloro-1,2-propandiol (3-MCPD) in soy sauce from the Bulgarian market

The 3-monochloro-1,2-propandiol (3-MCPD) levels in soy sauces which contained hydrolysed vegetable protein were evaluated for the Bulgarian market. For analysis of 3-MCPD, a gas chromatography–mass spectrometry (GC-MS) method was applied with a linear range of 0.03–2.00 μg mL^?1 and a limit of detection (LOD) of 2.3 μg kg^?1 and a limit of quantification (LOQ) of 3.4 μg kg^?1. At these levels, the standard deviation was 5.1%, with recoveries between 81% and 102%. The method was applied to the analysis of 21 samples of soy sauce from the Bulgarian market. Results ranged from 3.7 to 185.6 μg kg^?1. Soy sauces produced from hydrolysed soy protein contained higher levels of 3-MCPD than naturally fermented sauces. In 38.4% of samples of Bulgarian origin, the 3-MCPD content was above the EU limit of 20 μg kg^?1. In all analysed samples, 33.3% had a 3-MCPD content above the EU limit.     

Determination and surveillance of hydrocortisone and progesterone in livestock products by liquid chromatography-tandem mass spectrometry

A simple analytical method for the determination of hydrocortisone and progesterone in bovine, swine, and chicken muscle and eggs was developed. Hydrocortisone and progesterone were extracted with acetonitrile and subsequently cleaned-up using an Oasis^® HLB mini-cartridge. The method was validated in accordance with Japanese guidelines and exhibited trueness from 86.6% to 104.3% and precision (relative standard deviations (RSDs) of repeatability and within reproducibility were under 8.7% and 11.7%, respectively). The method was applied to 103 bovine muscle, 137 swine muscle, 69 chicken muscle and 52 egg samples that were commercially available in Tokyo, Japan. The hydrocortisone concentration was 0.9–41.2 µg kg^?1 in all bovine muscle samples, with an average of 7.7 µg kg^?1 and a median of 6.2 µg kg^?1. The progesterone concentration in 50 samples exceeded the limit of quantification (LOQ) and reached a maximum of 95.4 µg kg^?1. Hydrocortisone was also detected in all swine muscle samples at concentrations of 2.0–56.0 µg kg^?1. Its average and median concentrations amounted to 13.1 and 11.3 µg kg^?1, respectively. Twenty-three samples contained progesterone levels surpassing the LOQ, with a maximum concentration of 107.0 µg kg^?1. No chicken muscle samples contained any of the analytes. The progesterone concentration was 15.5–200.0 µg kg^?1 in all egg samples, with an average of 95.4 µg kg^?1 and a median of 90.5 µg kg^?1.     

Aflatoxins and ochratoxin A in export quality raisins collected from different areas of Pakistan

During 2012–2014, 170 samples of export quality raisins were collected from different vendors in Pakistan. The collected samples were analysed for the presence of aflatoxins (AFs) and Ochratoxin A (OTA) contamination using high-performance liquid chromatography technique. The limit of detection and limit of quantification of AFs/OTA were 0.12/0.10 and 0.36/0.30 µg kg^?1, respectively. Only 5% of the samples were contaminated with AFs, ranging 0.15–2.58 µg kg^?1 with a mean of 0.05 ± 0.26 µg kg^?1. None of the raisin samples exhibited AFs contamination above the maximum limit (ML = 4 µg kg^?1) as set by the European Union (EU). About 72% of the samples were contaminated with OTA, ranging 0.14–12.75 µg kg^?1 with a mean of 2.10 ± 1.9 µg kg^?1. However, in 95.3% of the tested samples, OTA level was lower than the ML of 10 µg kg^?1 as regulated by the EU. Apparently, a strict and continuous monitoring plan, including regulatory limits, improves food safety and quality for all types of commodities.     

Distribution of semduramicin in hen eggs and tissues after administration of cross-contaminated feed

Semduramicin is an ionophore coccidiostat used in the poultry industry as a feed additive. Cross-contamination of feeds for non-target animals with semduramicin is unavoidable. However, it is not known whether undesirable residues of semduramicin may occur in food after cross-contaminated feed is administered to animals. The aim of the work was to determine the levels of semduramicin in hen eggs (yolks and albumen) and tissues (liver, muscle, spleen, gizzard, ovarian yolks and ovaries) after administration of feed contaminated with 0.27 mg kg^?1 of this coccidiostat. The residues were determined using LC-MS/MS. The distribution pattern confirmed the high lipophilicity of semduramicin. Residues were found mainly in egg yolks (28.8 µg kg^?1), ovarian yolks (19.5 µg kg^?1) and liver (2.57 µg kg^?1), while hens’ muscle was free from semduramicin (LOD = 0.1 µg kg^?1). Among edible tissues, the maximum level (2 µg kg^?1) was exceeded only in the liver.     

Aflatoxin evaluation in ready-to-eat brazil nuts using reversed-phase liquid chromatography and post-column derivatisation

A high-performance liquid chromatography-fluorescence (HPLC-FD) method for aflatoxin quantification in brazil nuts was developed. Samples of brazil nuts collected in Brazilian markets were extracted with methanol:water and cleaned using an immunoaffinity column. Aflatoxins were eluted with methanol and a post-column derivatisation was performed with bromine, using a Kobra Cell system. The optimised method for total aflatoxins was sensitive, with detection and quantification limits of 0.05 and 0.25 µg kg^–1, respectively. The method was accurate, with recovery values of 87.6%; 85.3% and 85.0% for 0.5, 5.0 and 14.6 µg kg^–1 spiked levels, respectively. It was shown that the method was applicable to brazil nuts. From a total of 95 brazil nut samples analysed from 21 São Paulo supermarket samples and 51 Manaus and 23 Belém street markets samples, 37.9% showed detectable levels of aflatoxins and three exceeded the recommended Codex Alimentarius limit of 10 µg kg^–1 for ready-to-eat brazil nuts.     

Rapid and sensitive method for the determination of four EU marker polycyclic aromatic hydrocarbons in cereal-based foods using isotope-dilution GC/MS

A rapid and sensitive method has been developed for the determination of the four European Union marker polycyclic aromatic hydrocarbons (PAHs; benz[a]anthracene, chrysene, benzo[b]fluoranthene and benzo[a]pyrene) in some cereal-based foods. The method is based on pressurised liquid extraction (PLE), solid-phase extraction clean-up (SPE) and isotope-dilution gas chromatography with mass-spectrometric detection (GC/MS). The developed method was calibrated for the content range of 0.05–12.5 µg kg^?1 (expressed on a product basis). Recoveries of PAH were monitored in each sample via the recovery of ¹³C-labelled PAHs. Recovery values were in the range between 86% and 91%, with relative standard deviations (RSDs) between 5% and 9%. The achieved limits of detection for all analytes were below 0.05 µg kg^?1. The applicability of the method for the analysis of routine samples was studied by the analysis of a set of commercial bread and breakfast cereal samples. In all analysed samples, benzo[a]pyrene (BAP) was the most prevalent PAH with the content between 0.09 and 0.30 µg kg^?1. On average, samples showed low levels of the sum of the four EU marker PAHs (ΣPAH4) that ranged between 0.11 and 0.22 µg kg^?1 for bread samples and between 0.23 and 0.87 µg kg^?1 for breakfast cereal samples. The developed method was found suitable for the determination of PAHs in cereal-based foods like cornflakes and breads with total relative fat contents below 3.5%.     

Deposition and depletion of maduramicin residues in eggs after oral administration to laying hens determined by LC-MS

The coccidiostat maduramicin has been approved as a feed additive for chickens and turkeys, although it is prohibited for use in laying hens. In the present study, laying hens were divided into three groups and fed for 14 days with medicated feed containing maduramicin, at three different concentrations: 50, 100 and 500 µg kg^?1. Eggs were collected during treatment and for 26 days after the end of feeding with medicated feed. Maduramicin residues were found exclusively in egg yolk, with the highest concentration in egg yolk of 459 µg kg^?1 for the highest dose. The maximum concentration of maduramicin in whole egg was 16.6 µg kg^?1 for the group receiving feed containing the maximum permitted level of maduramicin in feed (50 µg kg^?1). The half-life of elimination of maduramicin, calculated for post-treatment days 1–10, was 6.5 days. Twelve days after drug administration, the concentration of the maduramicin in egg yolk for Group 3 (fed with 500 µg kg^?1 maduramicin) still exceeded 20 µg kg^?1, while the concentrations for Groups 1 and 2 were 1.2 and 2.7 µg kg^?1, respectively.     

Analysis of sterigmatocystin in cereals,animal feed,seeds, beer and cheese by immunoaffinity column clean-up and HPLC and LC-MS/MS quantification

A method is reported for the analysis of sterigmatocystin in various food and feed matrices using a commercial sterigmatocystin immunoaffinity column (IAC) for sample clean-up prior to HPLC analysis by UV with mass spectrometric detection (LC-MS/MS). Cereals (wheat, oats, rye, maize and rice), sunflower seeds and animal feed were spiked with sterigmatocystin at levels from 0.75 to 50 µg kg^?1 to establish method performance. Using acetonitrile/water extraction followed by IAC clean-up, and analysis by HPLC with detection at 325 nm, recoveries ranged from 68% to 106%, with repeatability from 4.2% to 17.5%. The limit of quantification with UV detection in these matrices was 1.5 µg kg^?1. For the analysis of beer and cheese the sample preparation prior to IAC clean-up was changed to accommodate the different properties of the matrix, prior to analysis by LC-MS/MS. For beer and cheese spiked at 5.0 µg kg^?1 the recoveries were 94% and 104%, and precision (RSDs) were 1.9% and 2.9% respectively. The limits of quantification by LC-MS/MS in beer and cheese were 0.02 and 0.6 µg kg^?1 respectively. The sterigmatocystin IAC was demonstrated to provide an efficient clean-up of various matrices to enable this mycotoxin to be determined by either HPLC with UV detection or LC-MS/MS.     

Assessment of mercury and cadmium via seafood consumption in Italy: estimated dietary intake (EWI) and target hazard quotient (THQ)

Mercury (Hg) and cadmium (Cd) were quantified in fish, cephalopods and crustaceans from Italian supermarkets. Sample compliance with European dietary standards as well as human health risks according to provisional tolerable weekly intake (PTWI) and the methodology of target hazard quotient (THQ) were evaluated. Both element levels were under European legal limits, except for some fish having Hg and Cd contents exceeding or equal to critical values. Estimated weekly intakes (Hg: fish = 0.07–1.44 µg kg^?1 bw week^–1; cephalopods = 0.05–0.15 µg kg^?1 bw week^–1; crustaceans = 0.04–0.08 µg kg^?1 bw week^–1; and Cd: fish = 0.04–0.32 µg kg^?1 bw week^–1; cephalopods = 0.07–0.27 µg kg^?1 bw week^–1; crustaceans = 0.05–0.11 µg kg^?1 bw week^–1) as well as THQ < 1 were within safe limits. Although there seems to be no important risks associated with seafood consumption, Hg exposure was in some cases close to safety margins and thus levels of this metal should be under frequent surveillance.     

Polycyclic aromatic hydrocarbons in Italian preserved food products in oil

A method based on gas chromatography/ tandem mass spectrometry was used to assess levels of 16 EU priority polycyclic aromatic hydrocarbons (PAHs) in 48 preserved food products in oil including foods such as vegetables in oil, fish in oil and oil-based sauces obtained from the Italian market. The benzo[a]pyrene concentrations ranged from <0.04 to 0.40 µg kg^?1, and 72.9% of the samples showed detectable levels of this compound. The highest contamination level was observed for chrysene with three additional PAHs (benzo[a]anthracene, benzo[b]fluoranthene and benzo[c]fluorene) giving mean values higher than the mean value for benzo[a]pyrene. Chrysene was detected in all the samples at concentrations ranging from 0.07 to 1.80 µg kg^?1 (median 0.31 µg kg^?1). The contamination expressed as PAH4 (sum of benzo(a)pyrene, chrysene, benzo(a)anthracene and benzo(b)fluoranthene), for which the maximum tolerable limit has been set by Commission Regulation (EU) No. 835/2011, varied between 0.10 and 2.94 µg kg^?1.     

Dietary exposure to chloropropanols of secondary school students in Hong Kong

This paper reports levels of 3-monochloropropan-1,2-diol (3-MCPD) and 1,3-dichloro-2-propanol (1,3-DCP) in a wide range of food items and estimates their dietary exposure for secondary school students in Hong Kong. Dietary exposure to chloropropanols was estimated using local food consumption data obtained from secondary school students in 2000 and the concentrations of 3-MCPD and 1,3-DCP in food samples taken from the local market. The dietary exposure to 3-MCPD for an average secondary school student consumer was estimated to be 0.063–0.150 µg kg^?1 body weight (bw) day^?1, whilst that for the high consumer was 0.152–0.300 µg kg^?1 bw day^?1. Both estimates fell below the provisional maximum tolerable daily intake of 2 µg kg^?1 bw established by the Joint Expert Committee on Food Additives (JECFA) and amounted to less than 20% of this safety reference value. The dietary exposure to 1,3-DCP for an average secondary school student consumer was estimated to be 0.003–0.019 µg kg^?1 bw day^?1, whilst that for the high consumer was 0.009–0.040 µg kg^?1 bw day^?1. The resulting margins of exposures were of low concern for human health. It could be concluded that both the average and high secondary school student consumers were unlikely to experience major toxicological effects of 3-MCPD and 1,3-DCP.     

Aflatoxin M1 in raw milk from different regions of São Paulo state – Brazil

A total of 635 raw milk samples from 45 dairy farms, from three regions of São Paulo state – Brazil, were evaluated during 15 months for aflatoxin M₁ (AFM₁). AFM₁ was determined by high performance liquid chromatograph with fluorescence detection. AFM₁ was detected (>0.003 µg kg^?1) in 72.9%, 56.3% and 27.5% of the samples from Bauru, Araçatuba and Vale do Paraíba regions, respectively. The mean AFM₁ contamination considering all the samples was 0.021 µg kg^?1. Furthermore, the concentration of AFM₁ was quite different among Bauru (0.038 µg kg^?1), Araçatuba (0.017 µg kg^?1) and Vale do Paraíba (<0.01 µg kg^?1) regions. Only three samples (0.5%) had higher contamination than the tolerated limit in Brazil (0.50 µg kg^?1) and 64 samples (10.1%) had a higher contamination than the maximum limit as set by the European Union (0.050 µg kg^?1). The estimated AFM₁ daily intake was 0.358 and 0.120 ng kg^?1 body weight per day for children and adults, respectively.     

Simple and fast spectrophotometric determination of low levels of thiabendazole residues in fruit and vegetables after pre-concentration with ionic liquid phase microextraction

There is a great importance of monitoring thiabendazole (TBZ) residues in fruits and vegetables to ensure food safety. Therefore, a new ionic liquid (IL) phase microextraction method using IL, 1-butyl-3-methylimidazoliumhexafluorophosphate [C₄mim][PF₆], as extracting solvent is proposed for simple and fast determination of low levels of TBZ in fruits and vegetables by spectrophotometry. The method is based on selective complex formation of TBZ with Cu(II) ions in presence of PF₆^– as counter ion at pH 5.5, and then microextraction of the complex into the fine micro-drops of IL phase. After optimisation of variables affecting microextraction efficiency, the analytical parameters of the method were determined by calibration curves. The method exhibits a linear relationship (0.3–280 μg L^?1), low detection limit (0.1 μg L^?1), good intra- and inter-day precision (2.4–4.5% as RSD_r%, 2.1–5.6% as RSD_R%), good recovery (≥95.1–98.2%) and high sensitivity enhancement factor (150) by solvent-based calibration curve. It allows a detection limit of 0.24 μg L^?1 and a range of 0.8–250 μg L^?1 by the matrix-matched calibration curve. After validation, the method was successfully applied to the determination of TBZ residues with method quantification limits in fruit and vegetables of 2.0 and 2.5 µg kg^?1 with and without adding polyvinylpyrrolidone (PVP-15) solution. Recoveries range from 85.5% to 98.2% after spiking (10, 50 and 100 µg kg^?1, n: 3).     

Development and application of a non-targeted extraction method for the analysis of migrating compounds from plastic baby bottles by GC-MS

In 2011, the European Union prohibited the production of polycarbonate (PC) baby bottles due to the toxic effects of the PC monomer bisphenol-A. Therefore, baby bottles made of alternative materials, e.g. polypropylene (PP) or polyethersulphone (PES), are currently marketed. The principal aim of the study was the identification of major compounds migrating from baby bottles using a liquid–liquid extraction followed by GC/MS analysis. A 50% EtOH in water solution was selected as a simulant for milk. After sterilisation of the bottle, three migration experiments were performed during 2 h at 70°C. A non-targeted liquid–liquid extraction with ethyl acetate–n-hexane (1:1) was performed on the simulant samples. Identification of migrants from 24 baby bottles was done using commercially available WILEY and NIST mass spectra libraries. Differences in the migrating compounds and their intensities were observed between the different types of plastics, but also between the same polymer from a different producer. Differences in the migration patterns were perceived as well between the sterilisation and the migrations and within the different migrations. Silicone, Tritan? and PP exhibited a wide variety of migrating compounds, whereas PES and polyamide (PA) showed a lower amount of migrants, though sometimes in relatively large concentrations (azacyclotridecan-2-one up to 250 µg kg^?1). Alkanes (especially in PP bottles), phthalates (dibutylphthalate in one PP bottle (±40 µg kg^?1) and one silicone bottle (±25 µg kg^?1); diisobutylphthalate in one PP (±10 µg kg^?1), silicone (up to ±80 µg kg^?1); and Tritan? bottle (±30 µg kg^?1)), antioxidants (Irgafos 168, degradation products of Irganox 1010 and Irganox 1076), etc. were detected for PP, silicone and Tritan? bottles. Although the concentrations were relatively low, some compounds not authorised by European Union Regulation No. 10/2011, such as 2,4-di-tert-butylphenol (10–100 µg kg^?1) or 2-butoxyethyl acetate (about 300 µg kg^?1) were detected. Migrating chemicals were identified as confirmed (using a standard) or as tentative (further confirmation required).     

Dietary exposure to mycotoxins of the Hong Kong adult population from a Total Diet Study

Dietary exposure of Hong Kong adults to mycotoxins and their metabolites including aflatoxins (AFs), ochratoxin A (OTA), fumonisins (FNs), deoxynivalenol (DON), acetyldeoxynivalenols (AcDONs) and zearalenone (ZEA) was estimated using the Total Diet Study (TDS) approach to assess the associated health risk to the local people. Sixty commonly consumed food items, collected in four seasons, were sampled and prepared as consumed. These mycotoxins were primarily found at low levels. The highest mean levels (upper bound) were: AFs, 1.50 µg kg^–1 in legumes, nuts and seed; OTA, 0.22 µg kg^–1 in sugars and confectionery; FNs, 9.76 µg kg^–1 in cereals and their products; DON and AcDONs, 33.1 µg kg^–1 in cereals and their products; and ZEA, 53.8 µg kg^–1 in fats and oils. The estimated dietary exposures of Hong Kong adults to the mycotoxins analysed were well below the respective health-based guidance values, where available. For AFs, the upper-bound exposure for high consumers is 0.0049 µg kg bw^–1 day^–1, which was estimated to contribute to about 7.7 (< 1%) of liver cancer cases when compared with 1222 liver cancer cases per year in Hong Kong. The percentage contributions of the estimated 95th percentile dietary exposures (lower and upper bound) to the health-based guidance values of individual mycotoxins were: ochratoxin A, 3.6–9.2%; fumonisins, 0.04–8.5%; deoxynivalenol and acetyldeoxynivalenols, 21.7–28.2%; and zearalenone 3.3–34.5%. The findings indicate that dietary exposures to all the mycotoxins analysed in this study were unlikely to pose an unacceptable health risk to the Hong Kong population.     

Dietary exposures to eight metallic contaminants of the Hong Kong adult population from a total diet study

Dietary exposures to eight metallic contaminants, aluminium (Al), antimony (Sb), cadmium (Cd), lead (Pb), methylmercury (MeHg), nickel (Ni), tin (Sn) and vanadium (V), of the Hong Kong adult population were estimated using the total diet study (TDS) approach. The estimated mean exposures of Al (0.60 mg kg^–1 bw week^–1), Sb (0.016–0.039 µg kg^–1 bw day^–1), Cd (8.3 µg kg^–1 bw month^–1), Pb (0.21 µg kg^–1 bw day^–1), MeHg (0.74 µg kg^–1 bw week^–1), Ni (3.1 µg kg^–1 bw day^–1), Sn (0.029–0.031 mg kg^–1 bw week^–1) and V (0.13 µg kg^–1 bw day^–1) were well below the relevant health-based guidance values (HBGVs) where available. However, dietary exposures to MeHg of women aged 20–49 years (child-bearing age) accounted for 150% of the provisional tolerable weekly intake (PTWI) and to Al and Cd of some high consumers were found exceeding or approaching the HBGVs. The major food contributors of MeHg were fish and seafood (90%), of Al were non-alcoholic beverages including tea (33%), and of Cd were vegetables (36%). MeHg exposure during pregnancy was a public health concern in Hong Kong due to potential health risks to the foetus. Results suggest that there is a need to continue monitoring the exposures to metallic contaminants, especially Al, Cd and MeHg, of the Hong Kong population.     

Oxytetracycline,tetracycline, chlortetracycline and doxycycline in pasteurised cow’s milk commercialised in Brazil

The aim of this study was to investigate the presence of tetracycline residues in pasteurised cow’s milk using high-performance liquid chromatography coupled with UV/VIS detection to determine the exposure of Brazilian’s population to antibiotic residues. One hundred samples collected from the State of Paraná, Brazil, were analysed. Three of these samples were contaminated at the following concentrations: 121.8 µg·kg^?1 for oxytetracycline, 93.5 µg·kg^?1 for tetracycline and 134.6 µg·kg^?1 for chlortetracycline (61.6 µg·kg^?1) and doxycycline (73.0 µg·kg^?1). The median tetracycline residue concentration found in the samples was 42.3 µg·kg^?1, and the estimated daily intake (EDI) was 0.05 µg Kg^?1 bw day^?1 in Brazil. These results demonstrate that the occurrence of tetracycline in Brazilian milk was low (3%) and only for 2% above the maximum residue limit, so the risk to the population from the presence of these residues in milk was low (<1% of the acceptable daily intake).