Perchlorate, nitrate, and iodide intake through tap water

Perchlorate is ubiquitous in the environment, leading to human exposure and potential impact on thyroid function. Nitrate can also competitively inhibit iodide uptake at the sodium-iodide symporter and thus reduce thyroid hormone production. This study investigates the intake of perchlorate, nitrate, and iodide attributable to direct and indirect tap water consumption. The National Health and Nutrition Examination Survey collected tap water samples and consumption data from 3262 U.S. residents during the years 2005-2006. The median perchlorate, nitrate, and iodide levels measured in tap water were 1.16, 758, and 4.55 μg/L, respectively. Measured perchlorate levels were below the United States Environmental Protection Agency (U.S. EPA) drinking water equivalent level for perchlorate (24.5 μg/L). Significant correlations were found between iodide and nitrate levels (r = 0.17, p < 0.0001) and perchlorate and nitrate levels (r = 0.25, p < 0.0001). On the basis of 24 h recall, 47% of the study participants reported drinking tap water; 89% reported either direct or indirect consumption of tap water. For the adult population (age ≥ 20 yrs) the median tap water consumption rate was 11.6 mL/kg-day. Using individual tap water consumption data and body weight, we estimated the median perchlorate, nitrate, and iodide dose attributable to tap water as 9.11, 11300, and 43.3 ng/kg-day, respectively, for U.S. adults. This perchlorate exposure dose from tap water is relatively small compared to the total perchlorate exposure dose previously characterized for the U.S. adults (median 64 ng/kg-day) and the U.S. EPA reference dose (700 ng/kg-day).     

Risk assessment of dietary exposure to perchlorate for the Austrian population

Perchlorate is frequently found as contaminant in a variety of food. Based on analytical data of perchlorate occurrence in food products from the Austrian market, this study calculated dietary perchlorate exposure of the Austrian population for the three age classes of adults, children and infants. Furthermore, a detailed risk assessment was conducted based on the tolerable daily intake (TDI) of 0.3 µg/kg body weight/day, established by the European Food Safety Authority in 2014. Calculations of a scenario of average food consumption did not indicate elevated health risks by dietary perchlorate uptake. Exposure estimates reached only 12%, 26% and 24% of the TDI for adults, children and infants, respectively. However, in a scenario of high consumption, the TDI was exceeded by all age classes with 132%, 161% and 156%. The major cause for this exceedance is the comparatively high perchlorate contamination of spinach, but also other leaf vegetables, legumes and pineapples, leading to elevated exposure of high consumers. Our calculations reveal that the current provisional intra-Union trade reference level for perchlorate in spinach of 0.2 mg/kg, advocated by the European Commission, is not sufficient to protect high consumers against possible health risks. In order to reduce health risks to a tolerable level for all consumers, lowering of the regulatory maximum perchlorate concentrations is indicated. Moreover, a generally diversified diet can also counteract excessive exposure to perchlorate as well as to other harmful food contaminants.     

Perchlorate and iodide in dairy and breast milk

Perchlorate inhibits iodide uptake and may impair thyroid and neurodevelopment in infants. Recently, we unambiguously identified the presence of perchlorate in all seven brands of dairy milk randomly purchased from grocery stores in Lubbock, TX. How widespread is perchlorate in milk? Perchlorate in 47 dairy milk samples from 11 states and in 36 human milk samples from 18 states were measured. Iodide was also measured in a number of the samples. Perchlorate was detectable in 81 of 82 samples. The dairy and breast milk means were, respectively, 2.0 and 10.5 microg/L with the corresponding maximum values of 11 and 92 microg/L. Perchlorate is present in virtually all milk samples, the average concentration in breast milk is five times higher than in dairy milk. Although the number of available measurements are few at this point, for breast milk samples with a perchlorate content greater than 10 microg/L, the iodide content is linearly correlated with the inverse of the perchlorate concentration with a r2 of >0.9 (n = 6). The presence of perchlorate in the milk lowers the iodide content and may impair thyroid development in infants. On the basis of limited available data, iodide levels in breast milk may be significantly lower than it was two decades ago. Recommended iodine intake by pregnant and lactating women may need to be revised upward.     

Furan in heat‐treated foods: Formation,exposure, toxicity,and aspects of risk assessment

Furan is formed in a variety of heat‐treated foods through thermal degradation of natural food constituents. Relatively high levels of furan contamination are found in ground roasted coffee, instant coffee, and processed baby foods. European exposure estimates suggest that mean dietary exposure to furan may be as high as 1.23 and 1.01 μg/kg bw/day for adults and 3‐ to 12‐month‐old infants, respectively. Furan is a potent hepatotoxin and hepatocarcinogen in rodents, causing hepatocellular adenomas and carcinomas in rats and mice, and high incidences of cholangiocarcinomas in rats at doses ≥2 mg/kg bw. There is therefore a relatively low margin of exposure between estimated human exposure and doses that cause a high tumor incidence in rodents. Since a genotoxic mode of action cannot be excluded for furan‐induced tumor formation, the present exposures may indicate a risk to human health and need for mitigation. This review summarizes the current knowledge on mechanisms of furan formation in food, human dietary exposure to furan, and furan toxicity, and highlights the need to establish the risk resulting from the genotoxic and carcinogenic properties of furan at doses lower than 2 mg/kg bw.     

Bisphenol s, a new bisphenol analogue, in paper products and currency bills and its association with bisphenol a residues

As the evidence of the toxic effects of bisphenol A (BPA) grows, its application in commercial products is gradually being replaced with other related compounds, such as bisphenol S (BPS). Nevertheless, very little is known about the occurrence of BPS in the environment. In this study, BPS was analyzed in 16 types of paper and paper products (n = 268), including thermal receipts, paper currencies, flyers, magazines, newspapers, food contact papers, airplane luggage tags, printing paper, kitchen rolls (i.e., paper towels), and toilet paper. All thermal receipt paper samples (n = 111) contained BPS at concentrations ranging from 0.0000138 to 22.0 mg/g (geometric mean: 0.181 mg/g). The overall mean concentrations of BPS in thermal receipt papers were similar to the concentrations reported earlier for BPA in the same set of samples. A significant negative correlation existed between BPS and BPA concentrations in thermal receipt paper samples (r = -0.55, p < 0.0001). BPS was detected in 87% of currency bill samples (n = 52) from 21 countries, at concentrations ranging from below the limit of quantification (LOQ) to 6.26 μg/g (geometric mean: 0.029 μg/g). BPS also was found in 14 other paper product types (n = 105), at concentrations ranging from 88%). To our knowledge, this is the first report on the occurrence of BPS in paper products and currency bills.     

Exposure of consumers to deoxynivalenol from consumption of white bread in Hungary

In view of the frequent occurrence of mycotoxins in cereals, a study was initiated to assess the exposure of the Hungarian adult population. Consumption data for 1360 individuals, based on a 3-day questionnaire, indicated that white bread accounted for the major intake of cereal-based products. Various cereal products were analysed for 16 mycotoxins by a LC/MS/MS multi-toxin method with LOD of 16 μg kg?1 and LOQ of 50 μg kg?1. Deoxynivalenol (DON) was most frequently detected, but no acetyl-deoxynivalenol was present in detectable concentrations. Consumer exposure was calculated with standard Monte Carlo probabilistic modelling and point estimates, taking into account bread consumption and DON contamination in independently taken wheat flour and wheat grain samples. Over 55% of cases the DON intake were below 15% of the provisional maximum tolerable daily intake (PMTDI) of 1 μg/(kg bw)/day. However, in 5-15% of cases, the intake from bread consumption alone exceeded the PMTDI. Wheat grain data led to the higher percentage. Intakes estimated from both data sets were at or below the acute reference dose (ARfD) of 8 μg/(kg bw)/day in 99.94-99.97% of cases.     

Polycyclic aromatic hydrocarbon residues in human milk, placenta, and umbilical cord blood in Beijing, China

This paper provides the results of an investigation on dietary intakes and internal doses of polycyclic aromatic hydrocarbons (PAHs) for nonsmoking women from Beijing, China. Concentrations of PAHs were measured by gas chromatography/mass spectrometry (GC/MS) for human milk, placenta, and umbilical cord blood samples from 40 nonsmoking women and for 144 composite food samples covering major food categories. Information on food consumption and estimated ingestion doses of PAHs by the cohort was also collected individually. Relationship among the studied human samples and relative importance of breastfeeding to the total exposure dose of infants were addressed. The median (mean and standard deviation) total concentrations of 15 PAHs in human milk, placenta, and umbilical cord blood with (or without) fat normalization were 278 (9.30 ± 5.75), 819 (35.9 ± 15.4), and 1370 (5.521 ± 3.71) ng/g of fat, respectively, and the corresponding levels of benzo[a]pyrene equivalent (B[a]P(equiv)) were 11.2 (0.473 ± 0.605), 16.2 (0.717 ± 0.318), and 13.1 (0.140 ± 0.225) ng/g of fat, respectively. The calculated intake of B[a]P(equiv) by Beijing cohort varied from 0.609 to 4.69 ng·kg(-1)·day(-1) with a median value of 1.93 (2.09 ± 0.921 mean ± standard deviation) ng·kg(-1)·day(-1). Significant correlations were found among human milk, placenta, and umbilical cord blood (p < 0.05) for low-molecular-weight PAHs, indicating selective transfer potential of individual PAHs from mother to fetus. Internal dose of PAHs was not in proportion to amounts of food ingestion, daily dietary intake, lifestyle, and social-demographic characteristics of the participants (p > 0.05). Ingested doses of PAHs (3.00-102 ng·kg(-1)·day(-1)), which were much higher than the inhaled doses (0.152-8.50 ng·kg(-1)·day(-1)), were 3-4 orders of magnitude lower than the recommended reference doses, unlikely to impose any obvious risk based on current knowledge.     

Perchlorate in dairy milk. Comparison of Japan versus the United States

Perchlorate has been considered a potential threat to human health, especially to developing infants and children due to its ability to inhibit iodide uptake by the sodium iodide symporter (NIS) of the thyroid. Although the U.S. has been the prime focus of perchlorate contamination, at least some of the similar sources of perchlorate exist across the world, and it has been detected in many types of foods and beverages worldwide. We present here perchlorate data from cow's milk samples from Japan (mean 9.4 +/-2.7 microg/L, n = 54), which are higher on average than those found in U.S. dairy milk samples reported by a 2004 Food and Drug Administration (FDA) study (5.9+/-1.8 microg/L, n= 104).     

Aluminium levels in Canadian infant formulate and estimation of aluminium intakes from formulae by infants 0-3 months old

Aluminium was determined in 282 cans of infant formulae and evaporated milks sold in Canada using graphite furnace atomic absorption spectrometry. Milk-based formulae contained average (range) concentrations of 0.129 (0.010-0.36), 0.217 (0.17-0.56) and 0.717 (0.19-2.49) micrograms/g ('as sold') in ready-to-use, concentrated liquid and powder formulae, respectively. The corresponding concentrations in the soy-based formulae were 1.98 (0.40-6.4), 1.41 (0.59-2.29) and 9.44 (3.15-18.0) micrograms/g. Evaporated milk contained 0.093 (0.022-0.34) micrograms/g. The levels varied extensively according to formula brand; e.g. for ready-to-use formulae, the range of average concentrations by formula brand were 0.42-3.28 micrograms/g for soy-based and 0.020-0.22 micrograms/g for milk-based products. Estimated aluminium ingestion from formula or milk by infants up to 3 months old ranged from 0.5 microgram per kg body weight per day (microgram/kg/day) or 2 micrograms/day for 0-1 month olds fed cow milk exclusively to 219 micrograms/kg/day (1260 micrograms/day) for 1-3 month olds fed only soy-based formulae. Consumption of only the formulae brand having the highest mean aluminium level (3.28 micrograms/g) by 1-3 month old infants could result in an intake of 363 micrograms/kg/day (2088 micrograms/day). The estimates assume that the sole source of aluminium is the formula or milk and do not include any potential contribution from other foods or water.     

Occurrence of eight bisphenol analogues in indoor dust from the United States and several asian countries: implications for human exposure

Bisphenol A has been reported to be a ubiquitous contaminant in indoor dust, and human exposure to this compound is well documented. Information on the occurrence of and human exposure to other bisphenol analogues is limited. In this study, eight bisphenol analogues, namely 2,2-bis(4-hydroxyphenyl)propane (BPA), 4,4'-(hexafluoroisopropylidene)diphenol (BPAF), 4,4'-(1-phenylethylidene)bisphenol (BPAP), 2,2-bis(4-hydroxyphenyl)butane (BPB), 4,4'-dihydroxydiphenylmethane (BPF), 4,4'-(1,4-phenylenediisopropylidene)bisphenol (BPP), 4,4'- sulfonyldiphenol (BPS), and 4,4'-cyclohexylidenebisphenol (BPZ), were determined in indoor dust samples (n = 156) collected from the United States (U.S.), China, Japan, and Korea. Samples were extracted by solid-liquid extraction, purified by automated solid phase extraction methods, and determined by liquid chromatography-tandem mass spectrometry (LC-MS/MS). The total concentrations of bisphenols (∑BPs; sum of eight bisphenols) in dust were in the range of 0.026-111 μg/g (geometric mean: 2.29 μg/g). BPA, BPS, and BPF were the three major bisphenols, accounting for >98% of the total concentrations. Other bisphenol analogues were rare or not detected, with the exception of BPAF, which was found in 76% of the 41 samples collected in Korea (geometric mean: 0.0039 μg/g). The indoor dust samples from Korea contained the highest concentrations of both individual and total bisphenols. BPA concentrations in dust were compared among three microenvironments (house, office, and laboratory). The estimated median daily intake (EDI) of ∑BPs through dust ingestion in the U.S., China, Japan, and Korea was 12.6, 4.61, 15.8, and 18.6 ng/kg body weight (bw)/day, respectively, for toddlers and 1.72, 0.78, 2.65, and 3.13 ng/kg bw/day, respectively, for adults. This is the first report on the occurrence of bisphenols, other than BPA, in indoor dust.     

Functional and proliferative effects of repeated low‐dose oral administration of furan in rat liver

Scope: Furan, a food contaminant formed during heat processing, induces hepatocellular tumors in rodents and high incidences of cholangiocarcinomas in rats even at the lowest dose (2 mg/kg b.w.) administered. Initial estimates suggested that human intake of furan may be as high as 3.5 μg/kg b.w./day, indicating a relatively narrow margin of exposure. The aim of this study was to establish dose–response data for cytotoxicity, regenerative cell proliferation and secondary oxidative DNA damage in livers of male F344 rats treated with furan at doses ≤2 mg/kg b.w. for 28 days. Methods and results: No significant signs of hepatotoxicity other than a mild, dose‐dependent increase in serum cholesterol and unconjugated bile acids, and no evidence of oxidative DNA damage were seen. Histopathological alterations and proliferative changes were restricted to subcapsular areas of the left and caudate liver lobes. Conclusion: Although statistically significant effects were only seen at the 2 mg/kg b.w. dose during the course of our study, a ～two and ～threefold increase in 5‐bromo‐2′‐deoxyuridine labeling index was observed at 0.1 and 0.5 mg/kg b.w., respectively, suggesting that chronic exposure to doses even below 2 mg/kg b.w. may cause proliferative changes in rat liver and highlighting the need to assess furan carcinogenicity at lower doses.     

Assessment of human exposure to polybrominated diphenyl ethers in China via fish consumption and inhalation

This study examined human exposure to polybrominated diphenyl ethers (PBDEs) associated with fish consumption and inhalation in China. The median intake of sigma7 PBDEs via human milk was 48.2 ng/day for nursing infants (0-1 years old) (a range of 23.4-99.1 ng/day). For all other age groups, the median intake of sigma11 PBDEs via fish consumption was 1.7-12.9 ng/day with a range of 0.59-56.3 ng/g. Additionally, human exposure to PBDEs via inhalation was 2.7-9.2 ng/day (a range of 0.72-108 ng/day). The median total sigma11 PBDEs intakes for nursing infants (6874 and 7372 pg/ kg b.w./day for males and females, respectively) were much higher than other age groups (215-608 pg/kg b.w./ day). No significant difference in the total PBDEs intakes was found between males and females. Of the 11 PBDEs congeners, BDE-47 was predominant in the total intake for nursing infants with a mean contribution of 38%, whereas BDE-209 was the dominant congener of total intake for other age groups, varying from 44 to 61%. Currently, the PBDEs levels in Chinese consumer fish and the total intakes of PBDEs via fish consumption were at the lower end of the global range. Compared with similar studies in other countries, however, human exposure to PBDEs via inhalation in China was relatively high. Overall, estimated daily intake of total PBDEs in the Chinese population was far below the LOAEL. However, studies are needed to further understand the fate and impact of PBDEs as PBDE-containing products are still used widely in large quantities in China.     

Fumonisin exposure through maize in complementary foods is inversely associated with linear growth of infants in Tanzania

Infants consuming maize‐based foods are at a high risk of exposure to fumonisins. This study explored the association between exposure of fumonisins from maize and growth retardation among infants in Tanzania. Mothers of 215 infants consented for their children to participate in this study. We estimated maize intake for each child by twice conducting a 24 h dietary recall and fumonisins level in the maize, using HPLC. Fumonisins exposure for each child was estimated by combining his/her maize intake and the fumonisins level in the maize. Of the infants, 191 consumed maize. The maize consumed by 131 infants contained fumonisins at levels varying from 21 to 3201 μg/kg. Fumonisins exposure in 26 infants exceeded the provisional maximum tolerable daily intake of 2 μg/kg body weight. At 12 months of age, infants exposed to fumonisins intakes above the provisional maximum tolerable daily intake of 2 μg/kg bodyweight were significantly shorter by 1.3 cm and 328 g lighter. It appears that the exposure to fumonisins is associated with growth retardation. This is the first study to report an association between fumonisins exposures and growth retardation.     

Lead and cadmium levels in commercial infant foods and dietary intake by infants 0-1 year old

Lead and cadmium levels were determined in 131 infant foods. Mean lead and cadmium levels were 19.3 and 3.3 ng/g for meats, 8.4 and 4.1 ng/g for vegetables, 14.9 and 0.58 ng/g for fruits and desserts, 9.6 and 0.53 ng/g for juices and drinks, and 32.8 and 33.6 ng/g for dry infant cereals. These data, combined with those from other recent surveys, yielded average dietary (food and water) intakes of lead and cadmium by infants 0-1 year old of 2.4 and 0.37 microgram/kg/day, respectively. Lead intakes were most strongly influenced by storage of infant formulas in lead-soldered cans. For infants 0-1 month old, they ranged from 0.5 microgram/kg/day when human or cow milk was fed to infants to 5.3 micrograms/kg/day (exceeding the FAO/WHO provisional tolerable daily intake, PTWI, of lead by children of 3.5 micrograms/kg) when ready-to-use formula stored in lead-soldered cans was fed. Cadmium intakes were most strongly affected by soya based formulas, and ranged, for 0-1 months olds, from 0.16 microgram/kg/day for infants fed human or cow milk to 0.50 microgram/kg/day for infants fed soya-based concentrated liquid formula. Cadmium intakes were all below the FAO/WHO PTDI of cadmium by adults of 0.96-1.2 micrograms/kg.     

Dietary acrylamide exposure among Finnish adults and children: the potential effect of reduction measures

A deterministic exposure assessment using the Nusser method that adjusts for within-subject variation and for nuisance effects among Finnish children and adults was carried out. The food consumption data covered 2038 adults (25-74 years old) and 1514 children of 1, 3 and 6 years of age, with the data on foods' acrylamide content obtained from published Finnish studies. We found that acrylamide exposure was highest among the 3-year-old children (median = 1.01 μg kg(-1) bw day(-1), 97.5th percentile = 1.95 μg kg(-1) bw day(-1)) and lowest among 65-74-year-old women (median = 0.31 μg kg(-1) bw day(-1), 97.5th percentile = 0.69 μg kg(-1) bw day(-1)). Among adults, the most important source of acrylamide exposure was coffee, followed by casseroles rich in starch, then rye bread. Among children, the most important sources were casseroles rich in starch and then biscuits and, finally, chips and other fried potatoes. Replacing lightly roasted coffee with dark-roasted, swapping sweet wheat buns for biscuits, and decreasing the acrylamide content of starch-based casseroles and rye bread by 50% would result in a 50% decrease in acrylamide exposure in adults. Among children, substituting boiled potatoes for chips and other friend potatoes and replacing biscuits with sweet wheat buns while lowering the acrylamide content of starch-based casseroles by 50% would lead to acrylamide exposure that is only half of the original exposure. In conclusions, dietary modifications could have a large impact in decreasing acrylamide exposure.     

超高效液相色谱-串联质谱法测定婴幼儿配方乳粉中氯酸盐和高氯酸盐

目的:建立超高效液相色谱-串联质谱法(Ultra performance liquid chromatography-tandem mass spectrometry,UPLC-MS/MS)同时测定婴幼儿配方乳粉中氯酸盐和高氯酸盐。方法:样品经过提取、离心、固相萃取柱净化和过滤,净化后滤液经负离子模式测定,并用内标法进行定量。结果:氯酸盐和高氯酸盐分别在2～500 μg/kg和1～250 μg/kg线性关系良好(R²>0.999),检出限均为4.5 μg/kg,定量限分别为15 μg/kg和7.5 μg/kg。对于方法正确度(n=9),在15.0、30.0 μg/kg和150 μg/kg 3个加标水平下,氯酸盐回收率为90.4%～104.3%;在7.5、15 μg/kg和75 μg/kg 3个加标水平下,高氯酸盐回收率为80.2%～106.2%。对于方法精密度(n=7),氯酸盐RSD为4.74%,高氯酸盐RSD为8.31%。结论:该方法线性、精密度和正确度数据均满足GB/T 27417—2017《化学分析方法确认和验证指南》的要求,适用于婴幼儿配方乳粉中氯酸...     

Lead concentration in meat from lead-killed moose and predicted human exposure using Monte Carlo simulation

Lead-based hunting ammunitions are still common in most countries. On impact such ammunition releases fragments which are widely distributed within the carcass. In Norway, wild game is an important meat source for segments of the population and 95% of hunters use lead-based bullets. In this paper, we have investigated the lead content of ground meat from moose (Alces alces) intended for human consumption in Norway, and have predicted human exposure through this source. Fifty-two samples from different batches of ground meat from moose killed with lead-based bullets were randomly collected. The lead content was measured by atomic absorption spectroscopy. The lead intake from exposure to moose meat over time, depending on the frequency of intake and portion size, was predicted using Monte Carlo simulation. In 81% of the batches, lead levels were above the limit of quantification of 0.03 mg kg(-1), ranging up to 110 mg kg(-1). The mean lead concentration was 5.6 mg kg(-1), i.e. 56 times the European Commission limit for lead in meat. For consumers eating a moderate meat serving (2 g kg(-1) bw), a single serving would give a lead intake of 11 μg kg(-1) bw on average, with maximum of 220 μg kg(-1) bw. Using Monte Carlo simulation, the median (and 97.5th percentile) predicted weekly intake of lead from moose meat was 12 μg kg(-1) bw (27 μg kg(-1) bw) for one serving per week and 25 μg kg(-1) bw (45 μg kg(-1) bw) for two servings per week. The results indicate that the intake of meat from big game shot with lead-based bullets imposes a significant contribution to the total human lead exposure. The provisional tolerable weekly intake set by the World Health Organization (WHO) of 25 μg kg(-1) bw is likely to be exceeded in people eating moose meat on a regular basis. The European Food Safety Authority (EFSA) has recently concluded that adverse effects may be present at even lower exposure doses. Hence, even occasional consumption of big game meat with lead levels as those found in the present study may imply an increased risk for adverse health effects. Children and women of child-bearing age are of special concern due to the neurodevelopmental effects of lead.     

Urinary bisphenol A concentrations and their implications for human exposure in several Asian countries

Bisphenol A (BPA) is an industrial chemical used in the manufacture of polycarbonate plastics and epoxy resins. Due to the potential of this compound to disrupt normal endocrinal functions, concerns over human exposure to BPA have been raised. Although several studies have reported human exposure to BPA in Western nations, little is known about exposure in Asian countries. In this study, we determined total urinary BPA concentrations (free plus conjugated) in 296 urine samples (male/female: 153/143) collected from the general population in seven Asian countries, China, India, Japan, Korea, Kuwait, Malaysia, and Vietnam, using high-performance liquid chromatography (HPLC) tandem mass spectrometry (MS/MS). On the basis of urinary BPA concentrations, we estimated the total daily intake. The results indicated that BPA was detected in 94.3% of the samples analyzed, at concentrations ranging from <0.1 to 30.1 ng/mL. The geometric mean concentration of BPA for the entire sample set from seven countries was 1.20 ng/mL. The highest concentration of BPA was found in samples from Kuwait (median: 3.05 ng/mL, 2.45 μg/g creatinine), followed by Korea (2.17 ng/mL, 2.40 μg/g), India (1.71 ng/mL, 2.09 μg/g), Vietnam (1.18 ng/mL, 1.15 μg/g), China (1.10 ng/mL, 1.38 μg/g), Malaysia (1.06 ng/mL, 2.31 μg/g), and Japan (0.95 ng/mL, 0.58 μg/g). Among the five age groups studied (≤ 19, 20-29, 30-39, 40-49, and ≥ 50 years), the highest median concentration of BPA was found in urine samples from the age group of ≤ 19 years. There was no significant difference in BPA concentrations between genders (male and female) or domicile of residence (rural and urban). The estimated median daily intakes of BPA for the populations in Kuwait, Korea, India, China, Vietnam, Malaysia, and Japan were 5.19, 3.69, 2.90, 2.13, 2.01, 1.80, and 1.61 μg/day, respectively. The estimated daily intake of BPA in the seven Asian countries was significantly lower than the tolerable daily intake recommended by the U.S. Environmental Protection Agency. This is the first study to document the occurrence of and human exposure to BPA in several Asian countries.     

Widespread occurrence of perchlorate in water,foodstuffs and human urine collected from Kuwait and its contribution to human exposure

Perchlorate is a thyroid hormone-disrupting compound and is reported to occur widely in the environment. Little is known on human exposure to perchlorate in Kuwait. In this study, 218 water samples, 618 commonly consumed foodstuffs and 532 urine samples collected from Kuwait were analysed to assess the exposure of the Kuwaiti population to perchlorate. For the estimation of daily intake of perchlorate, food consumption rates were obtained from the National Nutrition Survey in the State of Kuwait (NNSSK). The results showed that leafy vegetables accounted for a major share of perchlorate exposure among the Kuwaiti population at 0.062 µg kg^–1 bw day^–1 (36.2%), followed by fruits at 0.026 µg kg^–1 bw day^–1 (15.3%) and non-leafy vegetables at 0.017 µg kg^–1 bw day^–1 (10.1%). The urinary perchlorate geometric mean (GM) concentrations ranged from 8.51 to 17.1 µg l^–1 for the five age groups, which were higher than those reported in other countries. The estimated urinary perchlorate exposure for the Kuwaiti general population was 0.42 µg kg^–1 bw day^–1, which was higher than that reported for the United States. The dietary intake of perchlorate for the Kuwaiti population ranged from 0.14 to 0.67 µg kg^–1 bw day^–1 for the five age groups, with a mean total daily intake of 0.17 µg kg^–1 bw day^–1 for the general population. The highest estimated dietary mean daily intake of perchlorate (0.67 µg kg^–1 bw day^–1) was found for children at 3–5 years. The estimated dietary perchlorate exposure in Kuwait is higher than the recommended mean reference dose (RfD) but lower than that of provisional maximum tolerable daily intake (PMTDI) set by the Joint FAO/WHO Expert Committee on Food Additives (JECFA).     

Surveillance of perchlorate level in wine, seafood, polished rice, milk, powdered milk and yogurt

Perchlorate, which may be naturally occurring or artificial in origin, inhibits iodide uptake into the thyroid gland and disturbs thyroid function. In order to investigate perchlorate contamination in foods in Japan, perchlorate levels in 28 wine samples, 20 seafood samples, 10 polished rice samples, 30 milk (include whole milk, composition modified milk, low fat milk, processed milk, milk drink) samples, 10 powdered milk samples and 10 yogurt samples were measured. Perchlorate was found in all wine, milk, powdered milk and yogurt samples tested. Perchlorate levels ranged from 0.2 ng/g to 103 ng/g in wine samples, from 2 ng/g to 11 ng/g in milk samples, from 3 ng/g to 35 ng/g in powdered milk samples, and from 2 ng/g to 11 ng/g in yogurt samples. Perchlorate levels in the seafood samples were under the LOQ (0.8 ng/g) in 8 samples and ranged from 0.8 ng/g to 72 ng/g in 12 samples. In all polished rice samples, perchlorate level was under the LOQ (1.0 ng/g).