- A total diet study of sulphites, benzoates and sorbates
published August 2005
The Australian Total Diet Study (ATDS), formerly known as the Australian Market Basket Survey, is Australia’s most comprehensive assessment of consumers’ dietary exposure (intake) to a range of food chemicals including food additives, nutrients, pesticide residues, contaminants and other substances. The survey has been conducted approximately every two years, and this is the 21st such survey.
Past studies have consistently shown that Australian dietary exposures to pesticide residues and contaminants are well below Australian or international reference health standards and do not represent a public health and safety risk. Therefore, the scope and format of the study has been changed. In this and future studies, subsets of a broader range of chemicals found in food, including additives and nutrients, will be examined. The new smaller surveys will be conducted more frequently in response to the need for current information on the safety of substances in food. This change has allowed Food Standards Australia New Zealand (FSANZ) greater flexibility in focusing the study on specific food chemicals where further data on dietary exposure are desirable. The 21st ATDS estimates the dietary exposure of the Australian population to three specific food preservatives, namely sulphites, benzoates and sorbates. Representative foods believed to contain these preservatives were sampled and prepared to a ‘table-ready’ state before analysis, in order to provide realistic estimates of amounts of the preservatives in the food as consumed.
As in the 19th and 20th total diet studies, food consumption data derived from the 1995 National Nutrition Survey were used in the calculation of dietary exposures to the food preservatives.
This study provides valuable data that can be used for developing or amending food regulatory measures to ensure the protection of public health and safety. Data from previous studies were used by FSANZ during the Review of the Australian Food Standards Code and were integral to the development of the subsequent joint Australia New Zealand Food Standards Code.
Government food agencies in each State and the Northern Territory have provided invaluable assistance with this study and FSANZ acknowledges their very important contribution. A formal international expert peer reviewer was also engaged to evaluate the study and provided useful detailed comments.
21st Australian Total Diet Study
- Full Report - [ pdf 408 kb ]
including supplementary information
Summary of 21st Australian Total Diet Study
Food Standards Australia New Zealand (FSANZ) is a bi-national statutory authority that develops food standards for composition and labelling that apply to all foods produced or imported for sale in Australia and New Zealand.
The primary role of FSANZ, in collaboration with others, is to protect the health and safety of Australians and New Zealanders through the maintenance of a safe food supply. Regular monitoring of the food supply for pesticide residues, contaminants, nutrients, additives and other substances is conducted in both Australia and New Zealand. In Australia, this monitoring is conducted by a number of Federal and State government agencies, including FSANZ. The Australian Total Diet Study (ATDS) (previously named the Australian Market Basket Survey) is part of this monitoring. New Zealand also conducts a total diet study , administered by the New Zealand Food Safety Authority.
The purpose of the ATDS is to estimate the level of dietary exposure of the Australian population to a range of food chemicals including pesticide residues, contaminants, nutrients, additives and other substances that can be found in the food supply. In the ATDS, dietary exposure is estimated by determining the level of the substance in foods by laboratory analysis, and then combining this with the amount of food consumed, as determined in a separate study. In order to achieve more realistic dietary exposure estimates, the foods examined in the ATDS are prepared to a ‘table ready’ state before they are analysed. As a consequence, both raw and cooked foods are examined. This study estimated dietary exposure to three classes of preservatives, namely sulphites, benzoates and sorbates.
FSANZ coordinated the 21st ATDS, while Government food agencies in the States and Northern Territory purchased the food samples for their jurisdictions. Food samples for the Australian Capital Territory (ACT) were collected by FSANZ. Queensland Health Scientific Services carried out sample preparation and analyses.
Fifty-nine types of foods, representing mainly processed foods for which there are permissions to contain preservatives in the Australia New Zealand Food Standards Code (the Food Standards Code), were sampled during April and May 2003, and tested for the food preservatives sulphites, benzoates, and sorbates. In addition, minced meat, for which there are no additive permissions but State and Territory compliance data indicated illegal addition of sulphites, was sampled. The foods sampled included those that might be expected to show regional variation (regional foods), and those available nationwide and not expected to show regional variation (national foods). For each food, three samples were combined to give a composite sample that was chemically analysed to measure the levels of preservatives.
Diets for each individual in the representative age-gender groups were derived for exposure estimations, based on 24-hour diet recall food consumption data from the 1995 National Nutrition Survey (NNS). When using these data it should be noted that drawing conclusions about lifetime eating patterns from food consumption data derived from a single 24-hour diet recall, may lead to an over-estimation of dietary exposure. This over-estimation is magnified when considering 95th percentile consumers of the food chemical. More comprehensive data on multiple-day intakes, or frequency of consumption, may provide better estimates of long-term food consumption and dietary exposure.
Dietary exposure to each preservative was estimated using the food consumption data and the level of preservative present in each food. Results were calculated for ‘consumers only’, that is, those people who reported consuming food containing the chemical being assessed.
The dietary exposure estimates were calculated for a range of age-gender groups. These age-gender groups were young girls aged 2-5 years, young boys aged 2-5 years, school girls aged 6-12 years, school boys aged 6-12 years, teenage girls aged 13-18 years, teenage boys aged 13-18 years, adult females aged 19 years and over and adult males aged 19 years and over. In addition, dietary exposure was estimated for the entire female population aged two years and over and entire male population aged two years and over, representing a lifetime of exposure.
The estimated dietary exposure to each preservative from the Australian diet was compared to international reference health standards set by the Joint Food and Agriculture Organization (FAO) / World Health Organization (WHO) Expert Committee on Food Additives (JECFA). The reference health standard for the food additives is the Acceptable Daily Intake (ADI). The ADI is the amount of a food additive that can be consumed on a daily basis over a lifetime without appreciable health risk.
There are a number of uncertainties inherent in the dietary exposure assessment, including assumptions made in the calculations, certain limitations of the laboratory test data and sampling, and the relevance of the food consumption data that were derived from the 1995 NNS. Despite these uncertainties, the exposure assessments represent the best estimate of dietary exposure for sulphites, benzoates and sorbates using the available data. These uncertainties, however, should be taken into consideration in any subsequent risk management strategy.
Key results from this study were:
- Mean estimated dietary exposure to sulphites was less than or equal to 80% of the ADI for all population groups assessed.
- The mean estimated dietary exposure for the population aged two years and over, representing mean lifetime exposure, was approximately 35% of the ADI for males and 30% of the ADI for females.
- 95th percentile estimated dietary exposures exceeded the ADI for sulphites for nine of the 10 population groups assessed, ranging from approximately 85% of the ADI for teenage girls aged 13-18 years to approximately 280% of the ADI for young boys aged 2-5 years.
- 95th percentile estimated dietary exposure to sulphites for the population aged two years and over, representing lifetime exposure for a high consumer of sulphites, was approximately 130% of the ADI for males and females.
- Major foods contributing to dietary exposure to sulphites for children were beef sausages, dried apricots and cordial, and for adults were white wine, beef sausages and dried apricots.
- Mean estimated dietary exposure to benzoates was less than 50% of the ADI for all population groups assessed.
- Mean estimated dietary exposure for the population aged two years and over, representing mean lifetime exposure, was approximately 15% of the ADI for males and approximately 10% of the ADI for females.
- 95th percentile estimated dietary exposures to benzoates exceeded the ADI for young boys (approximately 140%) and young girls (approximately 120%) aged 2-5 years, and was equivalent to the ADI for schoolboys aged 6-12 years. All other population groups were below the ADI for 95th percentile estimated dietary exposures.
- 95th percentile estimated dietary exposure to benzoates for the population aged two years and over, representing lifetime exposure for a high consumer of benzoates, was approximately 60% of the ADI for males and approximately 50% of the ADI for females.
- Major foods contributing to dietary exposure to benzoates for young children aged 2-5 years were cordial, non-cola soft drinks and orange juice. For all other age groups assessed, non-cola soft drinks were the greatest contributor to dietary exposure to benzoates.
- Mean and 95th percentile estimated dietary exposure to sorbates was less than or equal to 40% of the ADI for sorbates for all population groups assessed.
- Mean estimated dietary exposure to sorbates for the population aged two years and over, representing mean lifetime exposure, was approximately 3% of the ADI for both males and females.
- 95th percentile estimated dietary exposure to sorbates for the population aged two years and over, representing lifetime exposure for a high consumer of sorbates, was approximately 15% of the ADI for males and approximately 10% of the ADI for females.
- The major food contributing to dietary exposure to sorbates for all population groups assessed was orange juice.
The results of this total dietary study indicate that for the majority of the population in all age groups the dietary exposure to sulphite, benzoates and sorbates is well below the relevant reference health standard and there is no public health and safety risk from the consumption of a balanced diet which includes some foods containing sulphites, benzoates or sorbates.
The results, however, also indicate that in some age groups consumption of sulphites and benzoates (but not sorbates) may exceed the relevant reference health standard for a proportion of the population. Therefore, for individuals in these age groups whose dietary pattern leads to a high regular consumption of sulphites and benzoates, there is a potential public health and safety risk.
It should be noted, however, that dietary modelling used in this survey is conservative and is likely to lead to an overestimate of actual dietary exposure. The reference health standard (the ADI) is also conservative and contains a significant margin of safety. Nevertheless, while there is currently no clinical evidence that high dietary exposure to sulphites and benzoates can cause adverse effects in humans, exceeding the ADI is a concern and effectively reduces the margin of safety provided by the reference health standard.
- Full Report - [ pdf 408 kb ] including supplementary information