Biomedical subjects

C V Breder

Publications and source records attributed to C V Breder.

13 recordsLinked to original sources

PubMed1997

Using a simple diffusion model to predict residual monomer migration--considerations and limitations.

A simple mathematical equation based on a diffusion model has been utilized recently to estimate migration of both acrylonitrile and styrene from polymers produced from these monomers which are used under a wide variety of food-contact applications. These calculated migration values have subsequently been used to estimate the US consumer's exposure to acrylonitrile and styrene from food stored in these materials. The basic assumptions integral to the model are discussed in relation to potential errors in migration estimates that could be experienced if the assumptions are not true. In addition to the discussion of the basic assumptions, factors affecting the migration predictions such as polymer 'ageing', temperature changes during the lifetime of the polymeric article, the effects of polymer-modifying materials (plasticizers, impact modifiers), and the physical form of the article or test sample are discussed.

Acrylonitrile↗

PubMed1995

A model for estimating the daily dietary intake of a substance from food-contact articles: styrene from polystyrene food-contact polymers.

An approach has been developed to estimate the exposure of consumers to styrene from polystyrene food-contact articles which incorporates published literature on the diffusion of styrene through polymeric materials and industry survey data on uses of polystyrene in food-contact applications. The approach has been shown to be quite practical and has yielded an exposure estimate of 3 ppb (9 micrograms/day) styrene, on average, in the daily diet of people in the United States. This value compares reasonably well with the value of 1-4 micrograms/day for residents of the United Kingdom in 1983. The value is also four orders of magnitude less than the acceptable daily intake calculated by the Styrene Information and Research Center.

Animals↗

PubMed1983

Determination of styrene migration from food-contact polymers into margarine, using azeotropic distillation and headspace gas chromatography.

Migration studies were conducted to determine the quantity of styrene that migrates from polymers into fatty foods, specifically margarine. Azeotropic distillation was used to isolate styrene from the margarine. Headspace gas chromatography with a Chromosorb 104 column and a flame ionization detector was used for quantitation. The quantitation limit for the method was about 25 ppb (wt/wt) styrene in margarine. On the average, greater than 90% of the styrene was recovered. Several commercial margarines were examined. The method and results of the migration studies are presented. There was no detectable migration of styrene into margarine.

Chromatography, Gas↗

PubMed1981

A multiresidue approach to the identification of food packaging-derived volatiles in foods and containers.

A rapid approach to the tentative identification of food packaging-derived volatile residues in foods and containers by use of headspace sampling, capillary gas chromatography, and a computer data search program is described. Headspace vapors of samples are analyzed on Ov-101 and Carbowax 20M columns. Peak retention time data of a sample on both columns are compared with those of common packaging raw materials, by-products, and processing agents maintained in a standard reference file. A list of possible identities based on the chromatographic peaks is compiled and printed out. Additional supporting data, such as relative peak response on each column, are examined to make a tentative identification. Other methods must be employed to confirm these identifications.

Chromatography, Gas↗

PubMed1981

Headspace sampling and gas chromatographic determination of styrene migration from food-contact polystyrene cups into beverages and food simulants.

Migration studies using coffee, tea, water, and 8% ethanol were conducted with various types of food-contact polystyrene cups. Study conditions simulated filing and storage at room temperature and hot-filling or pasteurization above 150 degrees F (65.6 degrees C). The quantity of styrene migrating was determined by headspace sampling and gas chromatography (GC). The GC column was 6% Carbowax 20M on Chromosorb 101 with quantitation via a flame ionization detector. Detection limits ranged from 3 to 10 ppb in various liquids. The method and results of the migration studies are presented.

Beverages↗

PubMed1980

Migration of ethylene glycol from polyethylene terephthalate bottles into 3% acetic acid.

Migration of ethylene glycol (EG) from polyethylene terephthalate (PET) bottles into the food simulate 3% acetic acid was studied using 32 fluid oz PET bottles filled with 3% acetic acid and stored at 32 degrees C for 6 months. Final concentration of EG in the 3% acetic acid migration solution was about 100 ppb, which is equivalent to about 94 microgram EG/bottle. A gas-liquid chromatographic procedure for quantitating EG was developed which is capable of measuring EG levels as low as 50 ppb in the migration solution.

Acetates↗

PubMed1980

Container-derived contamination of maple sirup with methyl methacrylate, toluene, and styrene as determined by headspace gas-liquid chromatography.

Samples of maple sirup and associated plastic packaging were examined for the presence of methyl methacrylate, toluene, and styrene by a head space gas chromatographic procedure. The volatile components common to the sirup and the plastic container were identified by gas chromatography-mass spectrometry. The quantities of these contaminants in the sirup were determined at ppb levels by the standard additions technique and repetitive headspace analysis.

Chromatography, Gas↗

PubMed1978

Headspace sampling and gas-solid chromatographic determination and confirmation of greater than or equal to 1 ppb vinyl chloride residues in polyvinyl chloride food packaging.

The determination and confirmation of residual vinyl chloride (VC) in polyvinyl chloride (PVC) food packaging materials are described. PVC packaging materials are dissolved in dimethylacetamide (DMAC). VC is sparged from solution with helium gas and collected in sealed vials of ethanol. VC is detected and quantitated by using a headspace sampling technique and standard gas-solid chromatography (GSC) with flame ionization detection. GSC peak heights of about 5% full scale deflection are obtained for samples of PVC containing 1 ppb VC. Polymer samples taken from tubing, blood bags, food packaging films, bottles, and unprocessed resin were analyzed. Residual VC levels ranged from 0.3 to 913 ppb. VC was confirmed by GSC-mass spectrometry, using selected ion recording of m/z 62 and 64 in conjunction with full mass scans to identify components eluting near VC.

Chromatography, Gas↗

PubMed1978

Gas-solid chromatographic procedures for determining acrylonitrile monomer in acrylonitrile-containing polymers and food simulating solvents.

A gas chromatographic method is described for acrylonitrile monometer (AN), using a nitrogen/phosphorus detector. Procedure for the analysis of AN in 5 food simulants (water, 3% acetic acid, heptane, 50% ethanol, and 8% ethanol) as well as in the polymer matrix are included. The quantitation limit for direct injection of AN/food simulant solution is 0.04 ng AN/microliter. AN-based polymers are dissolved in N,N-dimethylacetamide and injected directly. Residual AN in the polymer can be quantitated at the 0.5 ng/microliter level. Results of migration studies are also presented.

Acrylonitrile↗

PubMed1977

Gas-liquid chromatographic headspace technique for determination of vinyl chloride in corn oil and three food-simulating solvents.

A gas-liquid chromatographic headspace technique for the determination of vinyl chloride (VC) in corn oil, 50% ethanol, 3% acetic acid, and n-heptane is described. These food-simulating solvents and the corn oil are placed in septum-sealed bottles and heated to 90 degrees C, and aliquots of headspace vapor are injected into a gas-liquid chromatograph equipped with a flame ionization detector. VC may be quantitated at concentrations of 1 ppb or less. This technique was used to measure the migration of VC into corn oil and 50% ethanol from 2 unplasticized polyvinyl chloride sheets containing 0.28 and 0.44 ppm residual monomer.

Chromatography, Gas↗

PubMed1975

Gas-liquid chromatographic determination of vinyl chloride in vinyl chloride polymers, food-simulating solvents, and other samples.

The determination of vinyl chloride (VC) in polyvinyl chloride (PVC), vegetable oils, food-simulating solvents, mouthwashes, and blood anticoagulant solutions by gas-liquid chromatography is described. PVC polymers are disolved in either tetrahydrofuran or dimethyl acetamide. Vegetable oils are diluted with an equal volume of tetrahydrofuran. The resulting solutions are injected into a gas-liquid chromatograph equipped with a flame ionization detector. Mouthwashes, blood anticoagulant solutions, and 3 food-simulating solvents, 3% acetic acid, 50% ethanol, and heptane, are analyzed by direct injection into a chromatograph. Sensitivities are such that 0.05 ppm VC in solution or 1 ppm VC in PVC can be quantitated.

Anticoagulants↗

PubMedDate not supplied

Headspace gas chromatographic determination of residual 1,3-butadiene in rubber-modified plastics and its migration from plastic containers into selected foods.

A headspace gas chromatographic procedure has been developed for the determination of 1,3-butadiene in rubber-modified plastics and in some foods. Polymer solutions or foods are equilibrated in sealed vials at 90 degrees C, and headspace samples are injected into a gas chromatograph. 1,3-Butadiene residues are measured using a flame ionization detector and are quantitated by the method of standard additions or an external calibration curve. Refrigerator tubs, vegetable oil bottles, chewing gum, and foods in contact with this type of packaging were analyzed. Limits of quantitation varied with the matrix, ranging from 2 ng/g (ppb) in chewing gum to 20 ng/g in polymers. 1,3-Butadiene was found in one polymer at 53 ng/g with an 8% coefficient of variation. The procedure yields "apparent" trace levels of 1,3-butadiene, and confirmation by a complementary technique is required.

Butadienes↗

PubMedDate not supplied

New FDA migration cell used to study migration of styrene from polystyrene into various solvents.

A new cell was evaluated for studying the migration of components of plastic food packaging materials into various food simulating solvents. Data obtained using this cell to study the migration of styrene from polystyrene at 40 and 70 degrees C are presented. Food simulating solvents tested were: water; 3% acetic acid; 8, 20, 50, and 100% ethanol; corn oil; HB-307; heptane; hexadecane; and decanol. An iterative Basic computer program is described that fits the migration vs time data obtained to mathematical models, based on Ficks' law, yielding migrant/polymer diffusion coefficients (Dp). Dp values determined for styrene migration from polystyrene at 40 and 70 degrees C were 3 X 10(-13) and 4 X 10(-12) sq. cm/s, respectively.

Chemical Phenomena↗