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Regulation of endocrine-disrupting chemicals is reviewed in terms of hazard assessment (regulatory toxicology) and risk assessment. The current range of regulatory general toxicology protocols can detect endocrine toxicity, but specific endocrine toxicology tests are required to confirm mechanisms (e.g. oestrogenic, anti-androgenic). Strategies for validating new endocrine toxicology protocols and approaches to data assessment are discussed, and deficiencies in regulatory toxicology testing (e.g. lack of adrenocortical function assessment) identified. Recent evidence of a role of prolactin in human breast cancer also highlights deficiencies in regulatory evaluation. Actual human exposure to chemicals and the high-exposure example of chemicals in body-care cosmetics is reviewed with reference to evidence that common ingredients (e.g. parabens, cyclosiloxanes) are oestrogenic. The hypothesis and epidemiology concerning chemical exposure from body-care cosmetics (moisturizers, lotions, sun screens, deodorants) and breast cancer in women is reviewed, applying Bradford-Hill criteria for association and causality, and research requirements are identified.

Vitamin and mineral deficiencies adversely affect a third of the world's people. Consequently, a series of global goals and a serious amount of donor and national resources have been directed at such micronutrient deficiencies. Drawing on the extensive experience of the authors in a variety of institutional settings, the article used a computer search of the published scientific literature of the topic, supplemented by reports and published and unpublished work from the various agencies. In examining the effect of sex on the economic and social costs of micronutrient deficiencies, the paper found that: (1) micronutrient deficiencies affect global health outcomes; (2) micronutrient deficiencies incur substantial economic costs; (3) health and nutrition outcomes are affected by sex; (4) micronutrient deficiencies are affected by sex, but this is often culturally specific; and finally, (5) the social and economic costs of micronutrient deficiencies, with particular reference to women and female adolescents and children, are likely to be considerable but are not well quantified. Given the potential impact on reducing infant and child mortality, reducing maternal mortality, and enhancing neuro-intellectual development and growth, the right of women and children to adequate food and nutrition should more explicitly reflect their special requirements in terms of micronutrients. The positive impact of alleviating micronutrient malnutrition on physical activity, education and productivity, and hence on national economies suggests that there is also an urgent need for increased effort to demonstrate the cost of these deficiencies, as well as the benefits of addressing them, especially compared with other health and nutrition interventions.

This study assesses the validity and reproducibility of a 145-item self-administered food frequency questionnaire (FFQ) in a representative older population aged 63 to 80. Semi-quantitative FFQs were completed by 89% of 3,654 residents attending a community-based eye study in Sydney, Australia. The FFQ's validity was assessed against three, four-day weighed food records (WFRs) completed four months apart by 79 people. A further 152 subjects completed a repeat FFQ about a year after the baseline FFQ, of whom 131 completed a second repeat FFQ about six weeks later. Both short and long-term reproducibility of the FFQ were assessed using data from these subjects. Comparison of the FFQ with the average of the three, four-day weighed food records resulted in energy-adjusted Spearman correlations above 0.5 for most of the nutrients. The proportion of subjects correctly classified to within one quintile category for each nutrient intake ranged from 57% for zinc to 82% for vitamin C. with most nutrients correctly classified within one quintile for about 70% of subjects. Quadratic weighted kappas were reasonable, between 0.3 and 0.5 for most nutrients. The FFQ was highly reproducible in the short term, with correlations for most nutrients about 0.70 to 0.80 and acceptably reproducible in the longer term, with correlations mostly 0.60 to 0.70. The results verify that it is possible to use relatively simple, but comprehensive, self-administered FFQs to study nutrient exposures in large-scale epidemiological studies of the elderly and to expect reasonably high FFQ response rates.

The purpose of this work was to integrate existing chemical residue and food consumption data for individuals to improve estimates of the dietary intake of chemical residues in the population of Brisbane. Previous estimates of intakes from the Australian Market Basket Survey (AMBS) have been based on energy-adjusted 'hypothetical national diets' and so allow no assessment of variation in intakes between individuals or groups. Data on concentration of fenitrothion, chlorpyrifos-methyl, pirimiphos-methyl, heptachlor and dieldrin in selected foods were taken from reports of the AMBS. Food consumption data were based upon the National Dietary Survey of Adults (NDSA) 1983; the same data from which the hypothetical diets are derived. The distribution of estimated 24-hour intakes was adjusted to represent usual intakes. Mean intakes of all residues were about one third those reported previously. None of the observed diets contained levels of residues that were greater than the Acceptable Daily Intakes. These findings support reassurances to the public that residues of agricultural chemicals monitored in the AMBS do not pose a health risk.

Data describing the composition of dietary supplements are not readily available to the public health community. As a result, intake from dietary supplements is generally not considered in most dietary surveys and, hence, little is known about the significance of supplement intake in relation to total diet or disease risk. To enable a more comprehensive analysis of dietary data, a database of the composition of various dietary supplements has been compiled. Active ingredients of all dietary supplements sold in Australia are included in the Australian Register of Therapeutic Goods (ARTG), maintained by the Therapeutic Goods Administration. Products included in the database were restricted to those vitamin, mineral and other supplements identified in dietary data collected from studies conducted in southeast Queensland and New South Wales (850 supplements). Conversion factors from ingredients compounds to active elements were compiled from standard sources. No account has been made for bioavailability, consistent with current practice for food composition databases. The database can be queried by ARTG identification number, brand, product title, or a variety of other fields. Expected future developments include development of standard formulations for use when supplements are incompletely specified, and expansion of products included for more widespread use.

The influence of the food-service industry on compliance with the Australian dietary guidelines was investigated through three separate methods of data collection and analysis: a telephone survey of 1683 randomly selected Brisbane residents; telephone interviews with 69 food-service-industry operators and 10 face-to-face interviews with key stakeholders in industry and government. Nearly 40 per cent of respondents had consumed foods prepared by the food-service industry at least once on the day before the interview, mainly from restaurants, cafes and takeaway shops, in the form of fast-food or snacks. Consumption of these foods declined with age. Those consuming foods prepared by the food-service industry ate significantly less fruit, vegetables and dairy food and were therefore less likely to comply with the dietary guidelines. Outcomes from interviews with operators in the food-service industry show that food choices offered to consumers were the result of a dynamic interaction between consumer demand and operators' own tastes and perceptions of food quality. Key informant interviews show that public health nutrition programs will have limited effect without supportive environmental changes in the food-service industry supply. An effective means of increasing the likelihood of compliance with the Australian dietary guidelines will be to encourage food suppliers in ways that address their core business concerns simultaneously with the goals of health professionals.

To investigate the prevalence of food insufficiency and factors associated with it, two questions assessing household and individual food insufficiency were included in 13 regional health surveys conducted in Queensland in 1993. The surveys used computer-assisted telephone interviewing methodology. Of the 10,451 people interviewed, 9.7 per cent and 6.4 per cent reported household and individual food insufficiency, respectively, and 11.3 per cent reported at least one type. Prevalence was significantly higher in women than men and in urban than rural residents, and decreased monotonically with increasing age from 16.6 per cent in 18- to 30-year-olds to 1.7 per cent in over-70-year-olds. Higher prevalence also was associated with lower income, unemployment, single or separated, divorced or widowed status versus married (or de facto), one-adult households, and shared accommodation. Lower prevalence was associated with more education in those aged 50 and under but not in those over 50 years. Using logistic regression to control simultaneously for important sociodemographic factors, we found that risk of food insufficiency was most highly associated with age and income (threefold risk), unemployment and shared accommodation (twofold risk) and one-adult households, and being single versus separated, widowed or divorced (one-and-a-half-fold risk). Some differences in risks existed between men and women and between rural and urban residents, although none excluded the role of chance. Association of the items with lower reported fruit, vegetable and meat intake, poorer health status, and greater underweight supports their validity.

The effect of dietary copper deficiency on rat plasma lecithin: cholesterol acyltransferase (LCAT) activity was examined. Three groups of rats were used: ad libitum-fed copper-deficient group (0.6 microgram Cu/g diet); pair-fed control group (5.9 microgram Cu/g diet); and an ad libitum-fed control group (5.9 microgram Cu/g diet). Copper deficiency produced a significant hypercholesterolemia (57% increase, P less than 0.001) in 63 days with a significant increase in plasma free cholesterol (44%, P less than 0.001). Despite the significant increase in plasma free cholesterol, fractional and molar LCAT activity were markedly decreased (74.2%, P less than 0.001 and 63.7%, P less than 0.005, respectively) in copper-deficient rats. The results of this study suggest that dietary copper deficiency affects LCAT activity.

The effect of histidine-supplemented stock diets on plasma cholesterol and on the amelioration of the hypercholesterolemia by simultaneous copper supplementation was examined in rats. Weanling male Sprague-Dawley rats, five groups of 10 animals each, were fed ground stock diets unsupplemented or supplemented with 8% L-histidine, 8% L-histidine plus 222.8 micrograms Zn/g and 8% L-histidine plus 56.6 micrograms Cu/g. On day 46 plasma and liver cholesterol, copper and zinc concentrations were determined by colorimetry and atomic absorption spectrophotometry. Histidine supplementation produced hepatomegaly, depressed growth, a 131.8% (P less than 0.001) increase in plasma cholesterol and significant reductions in plasma copper and zinc and liver copper concentrations. The simultaneous feeding of histidine and zinc-supplemented stock diet failed to alter the hypercholesterolemia despite elevation in plasma zinc to values in excess of control animals. The simultaneous feeding of histidine and copper-supplemented stock diets abolished the hypercholesterolemia, reduced the hepatomegaly observed with histidine alone and elevated tissue copper concentrations to values in excess of control animals. Tissue copper and cholesterol concentrations showed significant negative correlations. No correlations between zinc and cholesterol were observed. The results suggest that histidine-induced hypercholesterolemia is due to changes in copper status, and is abolished by simultaneous copper supplementation.

Polyacrylamide gel electrophoresis in the presence of sodium dodecyl sulfate (SDS-PAGE) separates rat apolipoprotein B (apoB) into one lower and two higher molecular weight components. Of the latter, peptide I (PI) corresponds to human B-100, while the slightly faster-migrating peptide II (PII) lacks a human counterpart; the smaller species peptide III (PIII) corresponds to human B-48. We describe here a competitive radioimmunoassay which separately measures the amounts of total (i.e., PI + PII + PIII) and larger (i.e., PI + PII) rat apoB peptides, with the amounts of PIII obtained by difference. Standard rat PIII and combined PI + PII (PI,II) were isolated by high-pressure gel filtration liquid chromatography in the presence of SDS, and the PI,II was used as an immunogen to raise rabbit antisera which were capable of binding all three forms of rat apoB. However, Scatchard analysis showed this binding to represent two distinct types of antibodies: one high-affinity class which bound only PI,II and a second class which bound all apoB peptides with equal but lower affinity. Thus, since 125I-labeled PIII was displaced equally effectively by PI,II and PIII, but 125I-labeled PI,II was displaced only by PI,II, the unabsorbed antiserum could be used to measure either total apoB or PI,II alone, depending on the choice of labeled ligand. The validity of the assay for apoB peptides in very-low-density and low-density lipoproteins and in liver microsomes was verified by comparison with peptide determinations by SDS-PAGE.

It has been claimed that vitamin A deficiency increases the severity of malarial infection in rats. We measured parasitemia, mortality, serum retinol, liver retinol, spleen weight, and degree of xerophthalmia in vitamin A-deficient rats (A-), pair-fed control rats (A+PF), and ad libitum-fed control rats (A+AL) infected with Plasmodium berghei, a rodent malarial parasite. In experiments 1 and 2 vitamin A deprivation began at weaning. Parasitemia and mortality among mildly deficient (expt. 1, mean serum retinol 19 micrograms/dl) or acutely deficient rats (expt. 2, mean serum retinol less than 5 micrograms/dl) infected with P. berghei were not significantly different from those of infected A+AL or A+PF rats. Furthermore, when the mildly deficient rats were given a second, larger dose of P. berghei, all demonstrated complete immunity to the parasite. However, when vitamin A was withdrawn midway through pregnancy (expt. 3), the A- rats experienced significantly higher parasitemia and mortality during infection with P. berghei. Malaria caused a significant decrease in the serum retinol but not liver retinol of the A+PF and A+AL rats. Among the acutely deficient rats, xerophthalmia was significantly more prevalent and more severe among those infected with malaria than among those not infected with malaria. Malaria and vitamin A deficiency acted synergistically to increase spleen weight, and this interaction was highly significant. In these experiments, vitamin A deficiency decreased the rats' ability to recover from malaria, but only when the deficiency began early in life, was very severe, and the rats were young when infected.(ABSTRACT TRUNCATED AT 250 WORDS)