Barbara J. Petersen

Exposure to Acrylamide

This paper attempts to assess possible risks that may result from human exposure to dietary intake of acrylamide.

Effect of Substitution of High Stearic Low Linolenic Acid Soybean Oil for Hydrogenated Soybean Oil on Fatty Acid Intake

High stearic, low α-linolenic acid soybean oil (HSLL) has been developed via traditional breeding to serve as a substitute for partially hydrogenated soybean oils used in food manufacturing. The purpose of this study was to estimate the impact on fatty acid intake in the United States if HSLL were substituted for partially hydrogenated soybean oils used in several food categories, including baked goods, shortenings, fried foods, and margarines. Using National Health and Nutrition Examination Survey (NHANES) data (1999–2002), baseline intakes of five fatty acids and trans fatty acids (TFA) were determined at the mean and 90th percentile of fat consumption. Then intakes of these fatty acids were determined after HSLL was substituted for 100% of the partially hydrogenated soybean oils used in these four food categories. The results show that baseline intake of stearic acid is 3.0% energy at the mean and 3.3% energy at the 90th percentile. Use of HSLL could increase stearic acid intake to about 4–5% energy. Mean intakes of TFA could decrease from 2.5 to 0.9% energy, and intake of palmitic acid would remain unchanged. Use of HSLL as a substitute for partially hydrogenated soybean oils would result in changes in the fatty acid composition of the US diet consistent with current dietary recommendations.

Food consumption data in microbiological risk assessment.

The 1st International Conference on Microbiological Risk Assessment: Foodborne Hazards was held in July 2002. One of the goals of that conference was to evaluate the current status and future needs and directions of the science of microbial risk assessment. This article is based in part on a talk presented at that meeting. Here, we review the types of food consumption data available for use in microbial risk assessments and address their strengths and limitations. Consumption data available range from total population summary data derived from food production statistics to detailed information, derived from national food consumption surveys, about the types and amounts of food consumed at the individual level. Although population summary data are available for most countries, detailed data are available for a limited number of countries and may only be available in summary format. Despite the relatively large amount of detailed information collected by these national surveys, information crucial to microbial risk assessments, such as the specific types of foods, the eating patterns of susceptible populations, or an individuals propensity for consuming high-risk foods (e.g., eating undercooked hamburgers, raw shellfish, or temperature-abused foods), are not collected during these surveys.

Effect of substitution of low linolenic acid soybean oil for hydrogenated soybean oil on fatty acid intake.

Low linolenic acid soybean oil (LLSO) has been developed as a substitute for hydrogenated soybean oil to reduce intake of trans FA while improving stability and functionality in processed foods. We assessed the dietary impact of substitution of LLSO for hydrogenated soybean oil (HSBO) used in several food categories. All substitutions were done using an assumption of 100% market penetration. The impact of this substitution on the intake of five FA and trans FA was assessed. Substitution of LLSO for current versions of HSBO resulted in a 45% decrease in intake of trans FA. Impacts on other FA intakes were within the realm of typical dietary intakes. No decrease in intake of α-linolenic acid was associated with the use of LLSO in place of HSBO because LLSO substitutes for HSBO that are already low in α-linolenic acid.

Soy in wheat--contamination levels and food allergy risk assessment.

In the United States, packaged food ingredients derived from allergenic sources must be clearly labeled. However, no requirement exists to declare the presence of residues of raw agricultural commodities due to agricultural commodity comingling. Clinical reports of allergic reactions to undeclared soy in wheat-based products do not exist suggesting that a rather low degree of risk is posed by wheat-based products that are comingled with soy. Detectable soybean residues (>2.5 ppm soy flour) were found in 62.8% of commercially available wheat flours at concentrations of 3-443 ppm soy flour (1.6-236 ppm soy protein). Conservative probabilistic risk assessments predict a risk of allergic reaction among the most sensitive soy-allergic individuals of 2.8±2.0 per 1000 soy-allergic user eating occasions of foods containing wheat flour. However, the predicted reactions occur at exposure levels below the lowest eliciting dose observed to provoke objective reactions in clinical oral soy challenges. Given this low level of predicted risk and the lack of evidence for allergic reactions among soy-allergic consumers to wheat-based products, the avoidance of wheat-based products by soy-allergic consumers does not appear to be necessary.

Chapter 50 – Modeling Dietary Exposure with Special Sections on Modeling Aggregate and Cumulative Exposure

Publisher Summary This chapter focuses on methodology to estimate dietary exposures and provides options that range from worst-case screening assessments to much more refined and accurate assessments. Separate sections describe techniques that can be used to conduct aggregate and cumulative assessments. In many situations other assessment methods are necessary to identify the potential importance of a specific route relative to other pathways of exposure. These methods are generally referred to as indirect methods. Typically, indirect exposures are estimated for each route and then combined in order to estimate total exposure. Again, the three potential routes are oral, dermal, and inhalation. Indirect estimates of consumer exposure to a pesticide require data on the levels in the media as well as estimates of the amount of food consumed, extent of dermal exposure, and inhalation rates. Dietary, cumulative, and aggregate exposure methodologies are discussed in this chapter along with examples of the algorithms and data that can be employed for each method. Exposure assessments can be useful to identify the potential importance of a specific route relative to other pathways of exposure. That is, the method should identify the proportion of exposure that can result from oral, dermal, or inhalation or a combination of these routes. In many cases, exposures from more than one source need to be considered. The methods should allow the user to aggregate exposures as appropriate for the scenarios under consideration. Aggregation may be relevant to one chemical contained in one product that has multiple routes of exposure.

Chemistry, manufacturing and exposure assessments to support generally recognized as safe (GRAS) determinations

Identity, stability, purity, intended use levels in what foods and technical effects, and probable intake are among the key components in an assessment to support GRAS determinations. The specifications of identity of a food substance are an important component of the safety assessment as changes in the physical and chemical properties of a food substance can influence its technical effect in food and can influence its nutritional or toxicological properties of the food substance. Estimating exposure is a key determining step in the safety evaluation of a food substance. Intake assessment in GRAS determination is necessarily comprehensive based on cumulative exposure, i.e. proposed new uses plus background dietary exposure. Intake estimates for safety assurance in a GRAS determination also represent conservative overestimate of chronic exposure as they are based on 2-day average daily intake and the upper percentile (90th) intake among consumers. In contrast, in a nutrient assessment where realistic intake estimates are of interest, usual intake estimates are relied upon. It should also be noted that intake estimates for GRAS determinations are also more conservative than estimate of dietary exposure by EPA (FIFRA), where mean per capita are used to assess chronic exposure. Overall, for safety assurance, intake assessments in GRAS determinations are comprehensively cumulative and typically conservative overestimate of exposures.

Overview of Dietary Exposure

The general principles for exposure assessment in conjunction with the design and use of total diet studies (TDS) are presented. The most appropriate data, algorithms, and models for conducting an exposure assessment are discussed. TDS can provide data that are particularly useful for conducting assessments for chemicals found in multiple foods over long periods of time. TDS can combine food consumption data collected using a variety of different methods with the analytical results to estimate exposure for the entire population as well as for subgroups of interest. High-quality TDS exposure estimates based on levels of the chemical in foods as consumed provide the most realistic assessment of potential health risk to the population.