Bisphenol A (BPA) and its source in foods in Japanese markets

The determination of bisphenol A (BPA) and/or bisphenol A diglycidyl ether (BADGE) in foods sold in Japanese markets and in water leached from six epoxy resin cans with similar diameters was carried out using high-performance liquid chromatography (HPLC) with electrochemical detection (LC/ECD), LC-mass spectrometric detection (LC/MS) and LC-tandem mass spectrometric detection (LC/MS/MS). BPA concentrations were 0-842 ng g^-1 for 48 canned foods, 0-14 ng g^-1 for 23 foods in plastic containers, and 0-1 ng g^-1 for 16 foods in paper containers. No BADGE was detected in three canned foods. There was no difference in leaching concentrations of BPA into glycine buffers at pHs 8 and 11, and water. The amounts of BPA leached into water from six epoxy resin cans held at 121°C for 20 min were almost the same as the cans' contents and were much higher than the amounts leached from cans held at or below 80°C for 60 min. The amount leached depended on the type of can, but not on the amount of BADGE leached from the cans. Considerably more BPA than BADGE leached to water from six cans. Two cans whose contents had high concentrations of BPA showed no BADGE leaching even at 121°C, suggesting the different kinds of epoxy resin can linings from others. The results imply that the main source of human exposure to BPA is food from cans with linings that contain high percentages of BPA as an additive or an unforeseen contaminant.     

Determination of bisphenol A in foods using GC/MS

An analytical method using GC/MS was developed for bisphenol A (BPA) in foods and BPA was determined in canned foods and fresh foods such as vegetables, fruit and meat. BPA was extracted with acetone from the samples and the extract was concentrated at under 40 degrees C in vacuo to afford an aqueous solution, which was washed with hexane after alkalization and extracted with 50% diethyl ether-hexane after acidification. Extracts were cleaned up on a PSA and/or a C18 cartridge column, and BPA was derivatized with heptafluorobutyric anhydride and determined by GC/MS (SIM). This method was applicable to the detection and determination of BPA residues in food samples at the level of 1 ng/g. Among canned foods, BPA was found in 6 corned beef, 1 chicken, 9 sweet corn and 3 bean samples at the levels of 17-602 ng/g, 212 ng/g, 2.3-75 ng/g and 3.5-26 ng/g, respectively. BPA was also detected in 1 retort soup and 1 retort pack product at the levels of 11 ng/g and 86 ng/g, respectively. As for dairy products, BPA was not detected in butter and milk. Among fresh foods, BPA was detected in 2 fish and 3 liver samples at the levels of trace (tr)-6.2 ng/g and tr-2.2 ng/g, respectively. In vegetables, fruits and chocolates, a trace level of BPA was detected in only 1 chocolate. Traces of BPA were also detected in 3 samples of 6 boxed lunches.     

Intake of bisphenol A from canned beverages and foods on the Belgian market

Bisphenol A (BPA), a contaminant which may be present in the coating of cans, was determined in 45 canned beverages and 21 canned food items from the Belgian market. Beverages had an average BPA concentration of 1.0 ng/ml, while canned foods had a higher average concentration of 40.3 ng/g. The amount of BPA present in food items was dependent on the type of can and sterilisation conditions rather than the type of food. For example, BPA was not detected in non-canned beverages (<0.02 ng/ml), while non-canned food items had a very low average concentration of 0.46 ng/g. Using detailed information from the Belgian food consumption survey, the BPA intake of adults through canned foods and beverages was estimated to be 1.05 µg/day or 0.015 µg/kg body weight/day (assuming an average adult weight of 70 kg). Intake assessments, based on urinary metabolite concentrations from the literature, resulted in slightly higher BPA intakes (range 0.028–0.059 µg/kg body weight/day). This suggests that sources other than canned foods and beverages contribute to BPA exposure in humans.     

Concentrations of bisphenol A in the composite food samples from the 2008 Canadian total diet study in Quebec City and dietary intake estimates

A total of 154 food composite samples from the 2008 total diet study in Quebec City were analysed for bisphenol A (BPA), and BPA was detected in less than half (36%, or 55 samples) of the samples tested. High concentrations of BPA were found mostly in the composite samples containing canned foods, with the highest BPA level being observed in canned fish (106 ng g(-1)), followed by canned corn (83.7 ng g(-1)), canned soups (22.2-44.4 ng g(-1)), canned baked beans (23.5 ng g(-1)), canned peas (16.8 ng g(-1)), canned evaporated milk (15.3 ng g(-1)), and canned luncheon meats (10.5 ng g(-1)). BPA levels in baby food composite samples were low, with 2.75 ng g(-1) in canned liquid infant formula, and 0.84-2.46 ng g(-1) in jarred baby foods. BPA was also detected in some foods that are not canned or in jars, such as yeast (8.52 ng g(-1)), baking powder (0.64 ng g(-1)), some cheeses (0.68-2.24 ng g(-1)), breads and some cereals (0.40-1.73 ng g(-1)), and fast foods (1.1-10.9 ng g(-1)). Dietary intakes of BPA were low for all age-sex groups, with 0.17-0.33 μg kg(-1) body weight day(-1) for infants, 0.082-0.23 μg kg(-1) body weight day(-1) for children aged from 1 to 19 years, and 0.052-0.081 μg kg(-1) body weight day(-1) for adults, well below the established regulatory limits. BPA intakes from 19 of the 55 samples account for more than 95% of the total dietary intakes, and most of the 19 samples were either canned or in jars. Intakes of BPA from non-canned foods are low.     

Levels and temporal trend of bisphenol A in composite food samples from Canadian Total Diet Study 2008–2012

Food composite samples from the Canadian Total Diet Study which was conducted each year from 2008 to 2012 rotating between different cities were analysed for bisphenol A (BPA). The overall levels of BPA in the composite food samples from each of the five years from 2008 to 2012 were similar in general with averages (range) of 7.7 ng/g (0.20–106 ng/g), 7.8 ng/g (0.26–110 ng/g), 6.9 ng/g (0.20–84 ng/g), 7.7 ng/g (0.20–105 ng/g) and 9.0 ng/g (0.15–90 ng/g) for 2008, 2009, 2010, 2011 and 2012, respectively. Levels of BPA in most of the non-canned food composite samples were low and no particular trends were observed. In contrast, the trend of BPA levels in canned food composite samples over the five years (2008–2012) varies. BPA levels in most of the canned food composite samples from 2008 to 2012 were consistent in general (e.g. canned luncheon meat: 10–18 ng/g, canned baked beans: 18–25 ng/g). While BPA levels over the five years were found to decrease for some canned food composite samples (e.g., canned fish: 109 ng/g in 2009 vs. 51 ng/g in 2012), they were also found to increase for some other canned food composite samples (e.g. canned meat soups: 90–104 ng/g in 2011–2012 vs. 29 ng/g in 2008). Thus, recent changes in can coating for food packaging to BPA-free alternatives may have not been fully reflected in all canned food products over the period from 2008 to 2012. Continued monitoring is necessary to more fully assess the potential impact on dietary exposure by the use of BPA alternatives in food contact materials.     

Survey of bisphenol A and bisphenol F in canned foods.

Bisphenol A (BPA) and bisphenol F (BPF) have been determined in a range of canned foods. Sixty-two different canned foods were purchased from retail outlets in the UK from January to November 2000 and the contents extracted and analysed by GC-MS for BPA and BPF isomers. The following canned products were analysed: fish in aqueous media, 10 samples; vegetables, 10; beverages, 11; soup, 10; desserts, five; fruit, two; infant formula, four; pasta, five; and meat products, five. BPF isomers were not detected in any of the canned foods with detection limits of 0.005 mg kg(-1) for the 2,2' and 2,4' isomers and 0.01 mg kg(-1) for the 4,4' isomer. BPA was detected in 38 samples with a detection limit of 0.002 mg kg(-1). Of these, BPA was quantified in 37 canned foods at levels from 0.007 mg kg(-1), with one sample of meat containing a mean level of 0.38 mg kg(-1). All other samples contained <0.07 mg kg(-1) BPA.     

Survey of bisphenol a diglycidyl ether (BADGE) in canned foods.

2,2-Bis(4-hydroxyphenyl)propane bis(2,3-epoxypropyl) ether (BADGE) is used in the manufacture of lacquers for coating the inside of food and beverage cans. In June 1996 the EC Scientific Committee for Food temporarily increased the specific migration limit applying to BADGE to 1 mg/kg pending consideration of additional toxicological data. In order to find out if there is migration of BADGE from can coatings into foods, a 'worst case' sampling exercise has been conducted to survey those canned foods where the propensity for migration of BADGE was judged to be highest. The foods surveyed include canned fish in oil, meat and milk and, altogether, BADGE was determined in 181 retail samples. Analysis for BADGE was conducted, in duplicate, by HPLC with fluorescence detection with confirmation of BADGE identity by GC/MS analysis using selected ion monitoring. BADGE was found at levels exceeding 1 mg/kg in seven of the 15 canned anchovy samples and five of the 22 sardine samples purchased during the period September 1995-July 1996. Infrared analysis of the can coatings provided strong evidence that the higher BADGE levels found were associated with use of PVC organosol lacquers, although in some cases cans coated with organosols gave low BADGE results. For canned sardine samples found to contain greater than 0.5 mg/kg BADGE in the total contents, a replicate can was opened and separate analyses performed on the drained fish and the oil. The results clearly showed that BADGE concentrations in the oil were about 20 times higher than in the drained fish. Further samples of canned sardines and anchovies were purchased in June/July 1997 and, in all cases, BADGE levels were found to be below 1 mg/kg. In the other retail canned foods, BADGE was not detectable (DL = 0.02 mg/kg) or detected at concentrations well below the temporary SML of 1 mg/kg.     

Lead, chromium, tin, iron and cadmium in foods in welded cans

The levels of lead, chromium, tin, iron and cadmium in fruit and vegetables in welded tinplate cans were determined by atomic absorption spectrophotometry. The levels found were compared with those in foods in soldered tinplate cans and fresh foods. The results show that the lead levels in foods in welded cans were much lower than those in similar foods in soldered cans. Foods in unlacquered welded cans contain much more lead, chromium and tin than foods in lacquered welded cans. The cadmium and iron levels in canned fruit and vegetables in welded cans were similar to those found in the corresponding fresh foods.     

Tin and Iron Content of Canned and Bottled Foods

The tin and iron content of 14 different types of canned foods and of 5 different types of bottled foods were determined. No tin was detected in most bottled foods, but tin was detected in all canned foods. Storage of foods on the shelf for 4 months or in open cans in the refrigerator for 1 wk resulted in increased amounts of tin and iron in some of the canned foods. Those foods which were packed in totally lacquered cans accumulated little tin or iron during storage; those foods which were packed in unlacquered or partially lacquered cans generally accumulated significant amounts of iron and tin during storage. The tin content of the canned foods was not statistically correlated to the pH of the foods.     

Bisphenol A in domestic and imported canned foods in Japan

Bisphenol A (BPA) concentrations were surveyed in 100 domestic and 60 imported canned foods purchased from the Japanese market in 2011–12. BPA was extracted from the canned foods, derivatised by ethylation and analysed using GC-MS. In the domestic canned foods, the maximum and average BPA concentrations were 30 and 3.4 ng g^?1, respectively, while in the imported canned foods they were 390 and 57 ng g^?1, respectively. The BPA level in the domestic canned foods was significantly lower than that in the imported canned foods. Based on these results, the intakes of BPA from the domestic and imported canned foods in Japan were estimated as 644 ng person^?1 day^?1. The Japanese BPA intake was the second lowest following New Zealand, although imported canned foods increased. It was sufficiently lower than the tolerable daily intake of EFSA and the USEPA. The drastic reduction of BPA in the domestic canned foods should be due to the ‘BPA reduced cans’ that Japanese can manufacturers had developed in the late 1990s and became widely used in Japan.     

Bisphenol A in canned foods in New Zealand: an exposure assessment.

Exposure to bisphenol A (BPA) from the consumption of canned and bottled food has been determined for New Zealand adults. Eighty different canned foods purchased from retail outlets in Christchurch, New Zealand, between November 2003 and February 2004 were analysed for BPA concentration by gas chromatography/mass spectrometry. BPA was detected in all foods analysed except for soft drinks. Concentrations ranged from < 10 to 29 microg kg(-1), except for individual samples of tuna, corned beef and coconut cream, which were 109, 98 and 191 microg kg(-1) , respectively. The limit of quantitation was <10 microg kg(-1) for foods of low fat content (< 1%) and <20 microg kg(-1) for foods containing >1% fat. Mean concentration data were combined with 24-h dietary recall information for 4399 individual consumers. Mean and maximum exposures were 0.008 and 0.29 microg kg(-1) bw day(-1), respectively, well below the temporary tolerable daily intake of 10 microg kg(-1) bw day(-1) given by the European Commission in 2002. The results of the present survey suggest that the levels of BPA identified in canned foods are unlikely to be of concern to adult health, and there is no reason for consumers to change their consumption patterns as a result of these findings. When the concentration data found in the current survey are applied to an oestrogenicity model for an adult male, the contribution of BPA to the total oestrogenicity from 16 food components is 7%. The impact of this level of oestrogenicity remains unclear.     

LC-MS/MS analysis of bisphenol S and five other bisphenols in total diet food samples

ABSTRACT

It is already known that bisphenol S (BPS) has been used as a substitute for BPA in thermal papers in recent years. It is not clear, however, if BPS has also been used to replace BPA in can coatings as currently being speculated due to a lack of credible studies on migration of BPS from can coatings and occurrence data of BPS in foods. In this study, an LC-MS/MS method was developed for the analysis of BPS, along with several other bisphenols, and method detection limits for BPS varied from 0.0017 to 3.1 ng/g depending on the type of sample matrix and the amount of sample analysed. This method was used to analyse 159 different food composite samples from a recent Canadian total diet study. Bisphenol E (BPE), bisphenol B (BPB), and bisphenol AF (BPAF) were not detected in any of the 159 food composite samples, bisphenol F (BPF) was detected in only three samples (25–2360 ng/g), and bisphenol A (BPA) was detected in 10 samples (5.3–41 ng/g) which were all prepared from canned foods. BPS was not detected in any of the canned food composite samples but was detected in nine food composite samples prepared from meat and meat products (1.2–35 ng/g), indicating sources for BPS other than can coatings may be possible, which will be investigated in future studies.     

The determination of monomers and oligomers from polyester-based can coatings into foodstuffs over extended storage periods

The polymeric coating used in metal packaging such as cans for foods and beverages may contain residual amounts of monomers used in the production of the coating, as well as unreacted linear and cyclic oligomers. Traditionally, although designed for use with plastic food contact materials, food simulants have been used to determine the migration of monomers from coatings into foodstuffs. More recently, food simulants have also been used to determine oligomeric species migrating from can coatings. In the work reported here, the migration of both monomers and oligomers from polyester-based can coatings into food simulants and foodstuffs, some of which were towards the end of their shelf-life, is compared. The concentrations of monomers and selected oligomers in canned foods at the end of their shelf life were found to be significantly lower than those in food simulants, which in turn was lower than those in the extraction solvent acetonitrile.     

Thermal Sterilization of Conduction-Heated Foods in Plastic Cylindrical Cans Using Convective Boundary Condition

A mathematical model was developed to evaluate thermal processing of foods in cylindrical plastic cans. This model included convective heat transfer coefficients for heating and cooling media, thermal diffusivities of plastic can wall and the canned food, and contact conductance between the plastic wall and the canned food. Temperatures estimated by the model at the coldest point in a can agreed closely with those determined experimentally during thermal processing. Thermal diffusivity of can wall and heat transfer coefficients of heating and cooling media considerably influenced the sterilizing values of the processed food.     

Migration of bisphenol A from can coatings—effects of damage, storage conditions and heating

Bisphenol A (BPA) is an important monomer used in the manufacture of epoxy resins for internal food can linings. Experiments were conducted to investigate the effects of different storage conditions and can damage on the migration of BPA to foods. These experiments were conducted in a systematic fashion by filling empty epoxyphenolic coated cans with four foods: soup, minced beef, evaporated milk and carrots and a food simulant (10% ethanol). Filled cans of each food type or simulant were then sealed and processed using appropriate conditions, before storage at three different temperatures: 5°C, 20°C and 40°C. For each of the storage regimes, 50% of the cans were dented to establish if this would lead to increased BPA migration. Cans were removed from these stocks at intervals of 1, 3 and 9 months storage at 5°C and 20°C or 10 days, 1 and 3 months at 40°C. Some initial problems of heterogeneity between samples was overcome by determining the amount of BPA in food as well as in the can lining. It was found that 80-100% of the total BPA present in the coating had migrated to foods directly after can processing by pilot plant filling with food or simulant, sealing and sterilization. This level was not changed by extended storage (up to 9 months) or can damage, indicating most migration was occurring during the can processing step. There was no noticeable difference, in this respect, between the different foods or the food simulant. Analysis of control samples (foods fortified with ∼0.1 mg kg^-1 BPA and contained in Schott bottles) showed that BPA was stable under both processing and storage. Experiments were also conducted to investigate the potential effects, on the migration of BPA from can coatings, of cooking or heating foods in the can prior to consumption. Food cans were purchased and the food either cooked or heated in the can. BPA was analysed prior to and after the heating/cooking process. It was concluded from the results that there were no appreciable differences in the BPA level before and after cooking or heating.     

食品金属罐中14种双酚类物质迁移量的同时测定及杀菌过程对其迁移的影响

为了调查国内食品金属罐中双酚类物质的迁移水平,本文建立了同时测定食品金属罐中14种双酚类物质迁移量的高效液相色谱法,并研究了杀菌过程对双酚类物质迁移的影响及食品金属罐中双酚类物质的迁移规律.结果表明,14种双酚类物质在4种食品模拟物(4％体积乙酸、10％体积乙醇、50％体积乙醇和异辛烷)中线性关系良好,加标回收率为83...     

Estimates of per capita exposure to substances migrating from canned foods and beverages.

A study was undertaken by European industry to estimate the consumption of canned beverages and foodstuffs. European can production data were used with adjustments for imports into and out of the EU. It was further assumed that can production, with adjustments, equalled consumption. Owing to the lack of actual consumption country-by-country or household-by-household data throughout Europe, only per capita estimates of consumption were possible. Data were compiled country-by-country for seven major can-producing EU Member States and for eight different types of canned food and two types of canned beverage (beer and soft drinks). The per capita consumption of canned foods was 1.1 cans/person/week, and consumption of canned fish was estimated as 2.2 kg/person/year. The estimate of per capita consumption of canned food was 62 g/person/day or 22.6 kg/person/year. Canned beverages account for about 60% of the consumption of canned foodstuffs. The usefulness of per capita consumption of beverages is questionable because consumption habits may vary more widely than those for canned foods. However, as the migration into beverages is insignificant, these data were added for completeness. Per capita consumption of canned beverages is 67 cans/person/year or 61 g/person/day. From the average can sizes, the surface area of the cans consumed was estimated. The per capita surface area exposure was 0.55 dm(2)/person/day for canned foods and 0.55 dm(2)/person/day for canned beverages, giving 1.1 dm(2)/person/day. Migration of a substance at 0.02 mg dm(2) gives an exposure of 0.01 mg/person/day assuming a per capita consumption, using a surface area model. Migration at 0.12 mg kg(-1) in food gives an exposure of 0.007 mg/person/day using a weight model. Both models assumed migration into all food types at the same level, which is highly unrealistic. Exposure to BADGE from canned foods has been used as a case study. The best estimate for a worst case per capita exposure to BADGE and relevant derivatives was between 6 and 10 micro g/person/day, depending upon the approach and assumptions used.     

Recycled paper–paperboard for food contact materials: Contaminants suspected and migration into foods and food simulant

Contaminant residues in food packaging is a new challenge of our time, as it may pose a threat for consumers. Higher levels of contaminants were observed in food packaging made by recycled materials, even if little information is available for some groups of contaminants. The present study proposes a procedure for analyzing three different groups of organic contaminants in recycled paper and paperboard. Seventeen commercial samples were analyzed for the presence of bisphenol A (BPA), bis (2-ethylhexyl) phthalate (DEHP), nonylphenol monoethoxylate (NMP) and nonylphenol di-ethoxilate (NDP). Not all the samples contained all the contaminants; BPA was the only substance present in all the samples. The concentrations detected were quite high and, in most of the cases, in agreement with results reported in previous studies. Substance migration tests from spiked/non-spiked samples for two dry foods and Tenax® food simulant were undertaken. BPA migration quotients were always lower than 1%, whereas the migration quotients of DEHP were higher than 2.0%. The highest nonylphenols migration quotients were 6.5% for NMP and 8.2% for NDP. Tenax® simulates well the contaminants migration from paperboard to dry food, in some cases being even more severe than the food.     

Estimates of dietary exposure to bisphenol A (BPA) from light metal packaging using food consumption and packaging usage data: a refined deterministic approach and a fully probabilistic (FACET) approach

The FACET tool is a probabilistic model to estimate exposure to chemicals in foodstuffs, originating from flavours, additives and food contact materials. This paper demonstrates the use of the FACET tool to estimate exposure to BPA (bisphenol A) from light metal packaging. For exposure to migrants from food packaging, FACET uses industry-supplied data on the occurrence of substances in the packaging, their concentrations and construction of the packaging, which were combined with data from a market research organisation and food consumption data supplied by national database managers. To illustrate the principles, UK packaging data were used together with consumption data from the UK National Diet and Nutrition Survey (NDNS) dietary survey for 19–64 year olds for a refined deterministic verification. The UK data were chosen mainly because the consumption surveys are detailed, data for UK packaging at a detailed level were available and, arguably, the UK population is composed of high consumers of packaged foodstuffs. Exposures were run for each food category that could give rise to BPA from light metal packaging. Consumer loyalty to a particular type of packaging, commonly referred to as packaging loyalty, was set. The BPA extraction levels used for the 15 types of coating chemistries that could release BPA were in the range of 0.00005–0.012 mg dm^–2. The estimates of exposure to BPA using FACET for the total diet were 0.0098 (mean) and 0.0466 (97.5th percentile) mg/person/day, corresponding to 0.00013 (mean) and 0.00059 (97.5th percentile) mg kg^–1 body weight day^–1 for consumers of foods packed in light metal packaging. This is well below the current EFSA (and other recognised bodies) TDI of 0.05 mg kg^–1 body weight day^–1. These probabilistic estimates were compared with estimates using a refined deterministic approach drawing on the same input data. The results from FACET for the mean, 95th and 97.5th percentile exposures to BPA lay between the lowest and the highest estimates from the refined deterministic calculations. Since this should be the case, for a fully probabilistic compared with a deterministic approach, it is concluded that the FACET tool has been verified in this example. A recent EFSA draft opinion on exposure to BPA from different sources showed that canned foods were a major contributor and compared results from various models, including those from FACET. The results from FACET were overall conservative.     

Lead and tin in canned foods: results of the UK survey 1983-1987.

Concentrations of tin and lead in canned foods have been monitored since 1983 to determine the effects of recent changes in can-making technology. In the sample studied the proportion of foods contained in non-soldered as opposed to soldered cans has risen consistently during the survey and now accounts for 83% of all samples (excluding sardines). Foods contained in non-soldered cans have lower lead concentrations than those contained in soldered cans and this changeover is likely to result in a decrease in dietary lead intakes in the UK.