Wulf Becker

Serum concentrations of organochlorines in men: a search for markers of exposure

Analysis of single marker substances in serum could provide cost-effective assessment of human exposure to complex mixtures of organochlorines. We studied the serum concentrations of 10 polychlorinated biphenyl (PCB) congeners and 11 chlorinated pesticides and some of their metabolites in samples collected from 120 Swedish men (mean age 63 years, range 40-74 years) from the general Swedish population. The median concentrations of individual PCB congeners increased in the order PCB 52 < PCB 101 < or = PCB28 < PCB 105 < PCB 167 < PCB 156 < PCB 118 < PCB 138 < PCB 180 < PCB 153. The concentrations of o,p-DDT, o,p-DDE, p,p-DDD, alpha-HCH and gamma-HCH were in most cases below the quantification limit (2-4 ng/g lipid). Among the other chlorinated pesticides the median concentration increased in the order oxychlordane (12 ng/g lipid) < p,p-DDT < trans-nonachlor < beta-HCH < HCB < p,p-DDE (586 ng/g lipid). The observed concentrations of PCB and chlorinated pesticides were in the same range as those found in similar groups of men from Sweden and Norway, but lower than those found in male populations with recent occupational exposure or high environmental exposure. Strong relationships were found between the concentrations of single mono- and di-ortho PCB congeners and groups of PCB congeners in serum. In our group of men PCB 153 was a good marker substance for the concentration of sigma PCB and sigma di-ortho PCB concentrations in serum. Moreover, among the mono-ortho PCB congeners analyzed, PCB 156 could be used as a marker for the sigma mono-ortho PCB TEQ concentrations in serum in the studied group. No useful marker substances were found among DDT compounds and other chlorinated pesticides and metabolites, except for trans-nonachlor which predicted the concentration of the metabolite oxychlordane fairly well.

Under-reporting in dietary surveys – implications for development of food-based dietary guidelines

OBJECTIVEnTo illustrate issues related to under-reporting in dietary surveys relevant for development of food-based dietary guidelines.nnnSETTINGnFood and nutrient intakes in two national dietary surveys are analysed in relation to under-reporting using the concept of cut-off values for the ratio between energy intake and basal metabolic rate as well as biochemical markers of nutritional status.nnnRESULTSnSubjects with an implausibly low EI/BMR ratio had dietary patterns more close to recommended levels, e.g. lower fat intake and higher fibre intake, than those with acceptable energy intakes. Intakes of micronutrients were lower. This was due to both general and selective under-reporting of foods. Under-reporting was due to less frequent consumption, larger proportion of non-consumers and smaller portion sizes. Low EI/BMR ratios did not influence the characterisation of protein and micronutrient intake of low and high consumers of fruit and vegetable intake.nnnCONCLUSIONSnUnder-reporting can influence the usefulness of dietary data as a tool for developing food-based dietary guidelines, and the extent of under-reporting should be assessed using appropriate methods.

Comparability of household and individual food consumption data – evidence from Sweden

OBJECTIVEnComparison of household and individual food consumption.nnnDESIGN, SETTING AND SUBJECTSnCombined household and individual food consumption survey carried out in Sweden in 1989. A random sample of 3000 subjects aged 0-74 years, the household to which the subject belonged constituted the household unit. Each household recorded all the foods it purchased over a 4-week period, except food eaten outside the home. For the selected subject, excluding children <1 year old, food intake was obtained with a simplified 7-day record. Food consumption from the two data sets was compared for the whole sample and for one-person households, respectively.nnnRESULTSnReasonable agreement (+/-20%) was seen for many major foods including cereal products, milk, cheese, meat and meat products, and fish, and after correction for inedible part, fruit and vegetables. Purchases were lower for sweet bakery products, alcoholic beverages and potatoes, while the opposite was seen for oils and fats, cream and sugar. For one-person households the two data sets showed similar differences in consumption patterns between men and women. The gross differences observed can be explained by factors like home baking, eating out and recorded level of processing, e.g. as raw food including inedible part or as a prepared dish.nnnCONCLUSIONSnThe results show reasonable agreement between purchased and eaten amounts for aggregated food groups but marked differences were seen for some important individual items. Household-based consumption data are useful for many purposes provided the limitations of the data are accounted for.

Energy under-reporting in Swedish and Irish dietary surveys: implications for food-based dietary guidelines

An analysis of dietary survey data from Sweden and Ireland revealed that with a declining ratio of energy intake to estimated basal metabolic rate (EI:BMR), %energy from fat, saturated fat and carbohydrate fell while that of protein increased. However, where the definition of under-reporting is less strict, as in the Irish database (EI:BMR) < 1.27), the quantitative effect on macronutrient balance, while statistically significant, is not of such magnitude as to be of nutritional significance. However, with respect to foods, under-reporting was found to be of considerable significance in using such data to formulate food-based dietary guidelines. The Swedish data show that under-reporting of foods is associated with a decreasing percentage of consumers, decreasing intake per eating occasion and decreasing frequency of eating. The development of food-based dietary guidelines will involve comparisons of patterns of food intake among people with contrasting high or low intakes of target nutrients. The Swedish data compared food intakes for those with low or high intakes of saturated fatty acids (SFA) among under-reporters and acceptable reporters of energy intake. Whereas absolute values were always lower with the lower EI:BMR group (< 1.1) compared to the higher EI:BMR group (> 1.35) the ratio of intakes for the low vs. high SFA groups were broadly significant at either EI:BMR ratio. This paper highlights the difficulties that under-reporting will pose for food-based dietary guidelines.

Predicting percentage of individuals consuming foods from percentage of households purchasing foods to improve the use of household budget surveys in estimating food chemical intakes

OBJECTIVEnTo examine the hypothesis that there is sufficient agreement between percentage of households purchasing selected foods using household budget surveys and percentage of individuals consuming these foods as determined in individual-based surveys to allow the former to act as a surrogate for the latter when estimating food chemical intakes using household budget data.nnnDESIGNnDatabase study.nnnSETTINGnDatabases from Sweden, The Netherlands. Ireland and the UK.nnnSUBJECTSn319 foods (Sweden n = 60, The Netherlands n = 80, Ireland n = 90, UK n = 89).nnnRESULTSnPearson correlations demonstrated a high degree of linear association between % households purchasing and % consumers (r = 0.86). Regression analysis defined a close positive relationship between the two datasets (slope 0.95, intercept +2.74). Across countries, using the regression equation, the % households predicted % consumers to within 5% of the true value for between 33 and 48% of foods and to within 10% for between 53 and 78% of foods.nnnCONCLUSIONSnValues for % households can be used as a crude surrogate for % consumers and can thus play a role in improving estimates of food additive intake.

Aspects of Risk-Benefit Assessment of Food Consumption : Directions for the future

During the autumn of 2007, the National Food Administration in Sweden arranged a two-day seminar with the title Aspects of Risk-Benefit Assessment of Food Consumption - Directions for the Future. ...

Total Diet Studies in Sweden: Monitoring Dietary Exposure to Persistent Organic Pollutants by a Market Basket Approach

In Sweden, market basket studies (MBS) have been conducted in 1999, 2005, and 2010 by the use of similar methods, with the ambition to follow a 5-year scheme. Data on the mean Swedish consumption of common foods on the market were obtained from national food production and trade statistics, and listed food items were purchased from five major Swedish grocery chains and grouped into, at minimum, 12 different food groups (e.g. cereals, meat, fish, and dairy products). By the use of MBS methods, the Swedish mean exposure of both nutrients and potentially hazardous substances could be followed. Among other substances, POPs, such as PCBs, DDT, dioxins, and brominated flame retardants (e.g. PBDEs and HBCD) have been analysed. The data obtained are well suited for time trend studies, and could be used, e.g. in validation of other methods for exposure assessment.