Interacting Effects of Toxicants and Organic Matter on the Midge Chironomus riparius in Polluted River Water

Toxicants and organic matter in river water have contrasting impacts on macrofauna. Through manipulations of both factors, their interactive effects on organisms were evaluated. This way, an attempt was made to clarify the presence or absence of pollution-“tolerant” and -“sensitive” species in rivers affected by mixed sources of pollution. Under controlled conditions, larval growth of the “tolerant” midge Chironomus riparius was measured in different types of river water containing varying levels of particles (obtained by selective filtration) and toxicants (either complex mixtures or metals). Exposure of first-instar larvae to water from the polluted rivers Meuse and Dommel revealed that growth was less inhibited by toxicant levels in river water than expected based on laboratory toxicity tests. Factors present in polluted river water stimulated growth of midges to such an extent that inhibiting effects of high toxicant concentrations were neutralized, and at low toxicant levels, were overcompensated for. It was found that particulate matter has great potential to reduce inhibiting effects of toxicants on C. riparius, not (only) by reducing the bioavailability of toxicants, but by serving as a supplementary, superior food source. The success of the “pollution-tolerant” midge was not explained by tolerance of this species to toxicants, but by its ability to take advantage of coinciding organic enrichment. It is hypothesized that the extent to which beneficial effects of organic compounds on organisms occur is species specific.     

A Question of Balance: Nutrition, Health and Gastronomy

Given the higher proportion of manufactured foods now available which meet current dietary recommendations, the food supply in developed countries like Australia could be said to be “healthier”. Yet the “health” of the diet is often achieved at the expense of the “health” of the environment since ecological problems created by current food production and distribution methods remain unaddressed. Further, nutritional modifications which produce foods that are low in fat, sugar, salt and high in fibre do not necessarily address the concerns consumers have about the food supply. An emphasis solely on the physical health of populations, through improved diet, is out of keeping with current views on health which recognise the importance of overall well-being. Through the development of the concept of “sustaining gastronomy”, consumers, food manufacturers and producers, and food regulators can better address the problems inherent in the food system, including those of an environmental nature.     

Dissecting Obesogenic Environments: The Development and Application of a Framework for Identifying and Prioritizing Environmental Interventions for Obesity

Background. The “obesogenicity” of modern environments is fueling the obesity pandemic. We describe a framework, known as ANGELO (analysis grid for environments linked to obesity), which is a conceptual model for understanding the obesogenicity of environments and a practical tool for prioritizing environmental elements for research and intervention.Methods: Development of the ANGELO framework. The basic framework is a 2 × 4 grid which dissects the environment into environmental size (micro and macro) by type: physical (what is available), economic (what are the costs), political (what are the “rules”), and sociocultural (what are the attitudes and beliefs). Within this grid, the elements which influence food intake and physical activity are characterized as obe sogenic or “leptogenic” (promoting leanness).Results: Application of the ANGELO framework. The ANGELO framework has been piloted at the population level (island communities) to prioritize the settings/sectors for intervention and at the setting level (fast food outlets) to prioritize research needs and interventions. Environmental elements were prioritized by rating their validity (evidence of impact), relevance (to the local context), and potential changeability.Conclusions. The ANGELO framework appears to be a flexible and robust instrument for the needs analysis and problem identification stages of reducing the obe sogenicity of modern environments.     

Food branding influences ad libitum intake differently in children depending on weight status. Results of a pilot study

Environmental changes have facilitated the rapid increase in childhood obesity. One such change is increased presence of food marketing which promotes intake of high-fat, energy-dense foods. This study tested the hypotheses that overweight (OW) children are more sensitive to the intake-enhancing effects of food branding than non-OW children, and that the relationship between weight status and intake of branded foods is mediated by level of food brand awareness. Forty-three non-OW (n = 23) and OW (n = 20) children from diverse ethnic backgrounds participated in four dinnertime visits to test their intake of meals where food brands were present (“branded”) or absent (“unbranded”). Food brand awareness was assessed by testing children's abilities to match food brand logos with correct foods and name specific brands from recall. Weight and height were measured on the first visit to determine BMI z-score and weight status. OW children consumed significantly more energy per meal than non-OW. Child age and brand awareness were positively associated. OW children consumed an additional 40 kcal in branded vs. unbranded meals whereas non-OW children consumed 45 kcal less in branded meals. Overweight children showed greater responsiveness to food branding, and they may be at risk in environments that are highly inundated with messages about food.     

Impacts of sensory attributes and emotional responses on the hedonic ratings of odors in dairy products

Consumers often decide to purchase certain items as a result of prompt emotional responses evoked by the products; therefore, it is important to investigate the emotional responses stimulated by food samples, as well as the sensory attributes of the products. The aim of this study was to examine influences of sensory attribute and emotional response on olfactory hedonic ratings of dairy products. Additionally, we compared this effect between women and men subjects. Sensory attributes of six natural odors produced by commercial dairy products were evaluated by 9 trained panelists. In addition, 100 untrained panelists (50 women and 50 men) rated the emotional response stimulated by the 6 odors using 25 paired semantic differential scales and the hedonicity using a 9 cm line scale, respectively. Untrained panelists more liked “sweet aromatics,” “sour aromatics,” “fermented aromatics,” and “rich aromatics” over the other sensory attributes of dairy products. The olfactory hedonic ratings were increased when the odor was more characterized as “fragrant,” “attractive,” “comfortable,” “familiar,” “faint,” “natural,” or “modern.” Specific sensory attributes were found to be related to specific adjective pairs representing the emotional response. Moreover, the ratings of adjective pairs representing emotional response of odors and their influences on hedonic ratings differed significantly between sexes. In conclusion, our findings suggest that the emotional responses as well as the sensory attributes affect the hedonic ratings of odors in dairy products.     

Comparing the spatial genetic structures of the Flavescence dorée phytoplasma and its leafhopper vector Scaphoideus titanus

The Nearctic leafhopper Scaphoideus titanus Ball is the vector of “Flavescence dorée” phytoplasma (FDp) in European vineyards. We studied the genetic diversity and structure of S. titanus populations in France and of the FDp they carried. A total of 621 S. titanus individuals, sampled in 24 FDp-infected and uninfected vineyards, were genotyped using seven polymorphic microsatellite loci. The mean observed heterozygosity in S. titanus populations was between 0.364 and 0.548. There was evidence of only a low level of population genetic differentiation (mean F_ST = 0.027) suggesting that there is long-distance gene flow between S. titanus populations. This may be a consequence of the high migration capacity of the vector associated with large effective population size and, at least in part, of passive dispersion over long distances by the transport of grapevine-planting material carrying eggs. For each insect, FDp was detected and typed by nested-PCR followed by RFLP and sequencing of a 674 bp fragment of the FDp map gene. Twelve of the 24 populations were found to be infected by FDp, with the percentage of infected individuals varying from 3% to 29%. FDp isolates were classified into two FDp genetic clusters (FD1 and FD2), which differed by 12–13 SNPs. FD1 genotypes were detected in the insect populations at two sites and the FD2 genotypes in the other ten populations. Both FD1 and FD2 genotypes were found to be transmitted by the insect. No significant relationship was found between the genetic structure of these French S. titanus populations and the distribution of the various FDp strain types they carried. Nevertheless, overall genetic differentiation between FDp-infected and healthy S. titanus “subsamples” was found to be significantly higher than zero. These results suggest that FDp-infected S. titanus individuals are more philopatric (disperse less) than healthy S. titanus.     

Positive- and negative peer modelling effects on young children's consumption of novel blue foods

Objective: The effects of positive- and negative peer modelling on children's consumption of a novel blue food, presented in each of four snack meals during an “activity” day, were evaluated. It was predicted that: (i) novel food consumption would increase after positive modelling, but decrease after negative modelling; (ii) modelling effects would generalise to a second novel blue food when participants were alone when they ate their snack; (iii) that positive modelling would reverse the effects of negative modelling. Design: A mixed design was employed with random assignment to either Groups A, B, or C (equal numbers of males and females per group). Within groups, each participant received the novel food on four snack occasions. Group A received positive modelling of blue food consumption on the first and third occasions, but were alone when they received the foods on the second and fourth occasions; Group B had negative modelling on the first occasion, positive modelling on the third, and ate alone on the second and fourth; Group C ate alone on all four occasions. To measure generalisation, an additional blue food was presented in all second and fourth “alone” occasions. Participants: Thirty-five 5–7-year olds took part in Study 1, and 44 3–4-year olds in Study 2. Results: All main predictions were confirmed except that positive peer modelling did not reverse the effects of negative modelling in the 3–4-year olds. Conclusion: Negative peer modelling inhibits novel food consumption, and its effects are particularly difficult to reverse in younger children.     

Smoking and respiratory disease symptoms inrural Bangladesh

Respiratory disease (excluding tuberculosis) is a largely untargetted health problem in Bangladesh. This study emphasises both that existing morbidity is considerable and that it is sure to increase if smoking spreads further. In two poor village populations 71% of men though only 1% of women were current smokers (one or more cigarettes or bidi per day); about one in five had begun smoking before the age of 10 years. Most heavy smokers and all women smoked bidi (hand-rolled coarse tobacco sticks). Expenditure on smoking absorbed up to 5% of household income but, seemingly paradoxically, one of the lowest socio-economic groups had the heaviest consumption.For men the striking effect of smoking in increasing respiratory disease symptom prevalence at all ages is clear. Nearly all male smokers reported “cough” but so did four out of five men and women who had never smoked. There were too few women smokers for meaningful analysis. However, “morning phlegm”, “an episode of increased phlegm” and “wheezing” as well as being common for non-smokers of both sexes, were two to three times more frequent among women than men who had never smoked. In women there must certainly be other causal factors for respiratory symptoms apart from smoking, the most important are likely to be smoke from cooking fires and respiratory infections in childhood. Improving immunization coverage and the treatment of respiratory infections in childhood would be useful preventive strategies for both men and women. The most urgent public health measure is to reduce the prevalence of smoking.     

Adherence and weight loss outcomes associated with food-exercise diary preference in a military weight management program

The more consistently someone records their food intake the more likely they are to lose weight. We hypothesized that subjects who kept track via their preferred method would demonstrate higher adherence and therefore improved outcomes compared to those who used a non-preferred method. Participants were randomly assigned to use a paper, PDA, or Web-based diary and classified as “Preferred” if they used their preferred method and “Non-Preferred” if they did not. Days adherent to diary use were collected for 12 weeks. Weight, % body fat, waist circumference, and self-efficacy scores were measured at baseline, 6 and 12 weeks. Thirty nine participants completed the 12 week study. Fifty nine percent were male. The mean age was 35 and mean baseline BMI was 33 kg/m² (± 3.5). Forty four % (n = 17) used their “Preferred” diary method and 56% (n = 22) did not. Participants who used their preferred diary were more adherent to recording both food intake (64.2% vs. 43.4%, p = .015) and exercise (60.6% vs. 31.2%, p = .001). Though no difference was seen between groups on weight management outcomes, these results suggest that diary preference affects adherence to diary use.     

In Vitro Development of Parthenogenetic Eggs: A Fast Ecotoxicity Test with Daphnia magna?

In the present study, the authors investigated and defined development stages of Daphnia magna eggs that could be potential endpoints for sublethal toxicity tests with in vitro parthenogenetic egg cultures. Such an “egg test” could be a cost-effective alternative to the classic 21-day test with D. magna. Three main stages of embryonic development were considered: release of the egg external membrane, release of the internal membrane, and separation of the caudal spine. The first embryonic stage was attained approximately 30 h after transfer of eggs from ovaries to the brood chamber (considered as time zero), the second stage at 48 h, and the third stage at 68 h. Embryonic development was considered completed with the caudal spine separation. Thereafter, juveniles were able to swim in the water column. Egg mortality, duration of each egg stage, egg diameter, and egg abnormalities were investigated as potential endpoints. In vitro tests were carried out with several toxicants (DBS, 3,4-DCA, cadmium, and copper) and with acid mine drainage, sensitivity generally being higher than with the accepted chronic 21-day test with D. magna.     

Influences on Meat Avoidance Among British Students

Male and female undergraduates (18–23 years old; 68% in their first year;N=158) who had just chosen a vegetarian dish in a campus dining hall or restaurant reported a diversity of meat avoidance habits before arrival at University a few weeks previously. More women than men had avoided meat and other flesh foods, with the exception of fish. Consistently with the distinction between “red” and “white” meats, chicken and turkey were the least often avoided flesh foods among men and women. The only clear gradation from flesh-eating to vegetarianism was eating poultry and either beef/lamb or pork, eating only poultry and eating neither; fish was not on this Guttman scale, contrary to previous assumptions. Reasons for avoiding meat and perceived influences on preferences for food in their chosen vegetarian dish were elicited by open-ended interviews in 41 women from the meat-avoidance survey. Rationales spontaneously offered were as diverse as reported in previous studies, but always included at least two of the following: ethics of raising/killing animals, concern for health, sensory factors, disgust and influence of friends. In contrast, choices among described variants of the familiar dish were largely controlled by its sensory and nutritional features, presumably because other attributes had been factored out.     

Evaluating water supply and other health programs: Short-run vs long-run mortality effects

Development agencies use “cost-effectiveness” analyses for setting priorities among Primary Health Care programs, with “effectiveness” often measured by the short-term impact on young-child mortality. Using data on the long-term effects of water supply and sanitation improvements on mortality in urban France in the 19th century, it is shown that use of this criterion introduces systematic and serious biases in favour of specific medical interventions and against systemic environmental interventions.     

Detection and analysis of interactions between atrazine and sodium pentachlorophenate with single and multiple algal-bacterial populations

A multispecies-multitoxicant defined microcosm was studied by examination of its various components. Determination of population interactions showed thatChlorella vulgaris inhibitedAnkistrodesmus braunii by 32%. The presence ofChromobacterium violaceum resulted in a further inhibition ofA. braunii (17%) but its presence had no effect onC. vulgaris. Sensitivity of the two algae and the bacterium were determined for the toxicants atrazine1 and sodium pentachlorophenate, both singly and in combination. While both algae were sensitive to the toxicants, the combined effect of the toxicants on the individual populations was additive. In mixed cultures with one toxicant present, a synergistic interaction was detected between sodium pentachlorophenate andC. vulgaris with respect to A.braunii. Further, the combination ofA. braunii and atrazine withC. vulgaris resulted in an increased inhibition ofC. vulgaris. These observations indicate that biological-chemical interactions can occur as do population-population and chemical-chemical interactions. When mixed cultures of the algae were treated with both toxicants, chemical antagonism was observed. This antagonism was modified by the presence of the bacterium but it was not eliminated. It was concluded that the techniques allowed determination of the interactions in a complex microcosm.     

Atomic charges of individual reactive chemicals in binary mixtures determine their joint effects: an example of cyanogenic toxicants and aldehydes

Environmental contaminants are usually encountered as mixtures, and many of these mixtures yield synergistic or antagonistic effects attributable to an intracellular chemical reaction that pose a potential threat on ecological systems. However, how atomic charges of individual chemicals determine their intracellular chemical reactions, and then determine the joint effects for mixtures containing reactive toxicants, is not well understood. To address this issue, the joint effects between cyanogenic toxicants and aldehydes on Photobacterium phosphoreum were observed in the present study. Their toxicological joint effects differed from one another. This difference is inherently related to the two atomic charges of the individual chemicals: the oxygen charge of -CHO (O(aldehyde toxicant)) in aldehyde toxicants and the carbon-atom charge of a carbon chain in the cyanogenic toxicant (C(cyanogenic toxicant)). Based on these two atomic charges, the following QSAR (quantitative structure-activity relationship) model was proposed: When (O(aldehyde toxicant) -C(cyanogenic toxicant) )> -0.125, the joint effect of equitoxic binary mixtures at median inhibition (TU, the sum of toxic units) can be calculated as TU = 1.00 ± 0.20; when (O(aldehyde toxicant) -C(cyanogenic toxicant) ) ≤ -0.125, the joint effect can be calculated using TU = - 27.6 x O (aldehyde toxicant) - 5.22 x C (cyanogenic toxicant) - 6.97 (n = 40, r = 0.887, SE = 0.195, F = 140, p < 0.001, q(2) (Loo) = 0.748; SE is the standard error of the regression, F is the F test statistic). The result provides insight into the relationship between the atomic charges and the joint effects for mixtures containing cyanogenic toxicants and aldehydes. This demonstrates that the essence of the joint effects resulting from intracellular chemical reactions depends on the atomic charges of individual chemicals. The present study provides a possible approach for the development of a QSAR model for mixtures containing reactive toxicants based on the atomic charges.     

« Sécurité alimentaire » en milieu hospitalier : de la logique de crise à la logique de progrèsFood safety in hospital: of the logic of crisis to the logic of progress

Food safety in hospital is an essential preoccupation of hospital administrator. Rules have strongly changed since 1993 with publication of the directive “hygiene” 93/43/CEE. Registration in French Law have gained the “new approach” in food safety by setting objectives and laying down HACCP method. Under the aegis of CLANs, new objectives in food hygiene are centred around labelling and putting place of HACCP method right into care units.     

Chronic toxicity of cadmium to Chironomus riparius (Diptera: Chironomidae) at different food levels

The interacting effects of cadmium toxicity and food limitation on the midge, Chironomus riparius, were studied during chronic exposure in laboratory experiments. If the food was supplied ad libitum, both larval developmental time and mortality of the larvae were negatively affected by cadmium concentrations of 2.0–16.2 g/L. The number of eggs deposited per female and the mean life span of the imagines were not affected by cadmium. Integration of these separate effects into a population growth rate showed a clear reduction with increasing cadmium concentrations. Food limitation of unexposed larvae at high population density reduced fitness, judged on all parameters studied and consequently reduced the population growth rate (up to 85%).The effects on larvae, which were exposed to both cadmium and food limitation, differed considerably from the response to the individual stress factors. Exposure to cadmium increased mortality among food-limited first and second instar larvae. Consequently, the amount of food available for each surviving larva increased. At the two lowest concentrations studied (2.0 and 5.6 g Cd/L), these indirect positive effects of cadmium overruled the direct negative effects and caused an increase of the fitness of the food-limited exposed larvae compared to the food-limited, unexposed controls. At a concentration of 16.2 g Cd/L, the negative effects of cadmium on food-limited midges balanced the positive effects of reduced food limitation. At this concentration, the population growth rate did not differ significantly from the food-limited control any more. It is concluded that the indirect positive effects of cadmium on food limitation could eliminate negative, direct effects of low cadmium concentrations on food-limited chironomid populations.     

The “U” technique: A new method for Norplant implants removal

The standard technique for Norplant implants removal was compared with a new technique called the “U” technique, which employs the use of a modified no-scalpel vas deferens holding forceps to grasp and remove the capsules. Seventy-six women requesting Norplant implants removal were randomly assigned to Group 1 (standard removal technique) or Group 2 (“U” removal technique). Variables measured included: (a) time required for complete removal, (b) number of capsules not broken or damaged during removal, and (c) number of incisions required for removal of all six capsules. In clients with visible or palpable capsules, the standard removal technique required significantly more time to remove all six capsules, on average, than the “U” technique (19 versus 7 minutes, p < 0.001); also more capsules were damaged during removal (5.6 undamaged versus 6.0,p < 0.01). In addition, with the standard technique, five clients required two incisions for removal of all six capsules while none of the clients required more than one incision with the “U” technique. Our conclusion is that the “U” technique is a quicker and easier method of removing Norplant capsules than the standard technique.     

Are current species extrapolation models a good basis for ecological risk assessment?

Extrapolating the effects of toxicants with either the fixed application factor approach or one of the species sensitivity distribution models currently in widespread use presumes that toxicant effects on single, individual-level endpoints (e.g., survival, fecundity, and growth) reflect effects at the population level. Here, we consider if extrapolations derived on the basis of individual-level endpoints might be misleading with regard to risk assessment and, hence, risk management decisions for ecosystems. Both analytically and by simulation, we demonstrate that for populations with multiplication rates close to one, effects of toxicants at the population level likely are less than or equal to effects on individual life-cycle traits, suggesting that risk assessments based on the latter likely are protective of population-level impacts. We used Monte Carlo simulations to explore how both the frequency of different life-cycle types in a community as well as their relative sensitivity to toxicants influence the toxicant sensitivity distribution of the community as a whole. We compared the output of our simulations with predicted no-effect concentrations derived by an application factor approach and a log-normal distribution-based model, using no-observed-effect concentrations for juvenile survival as input variables in both cases. Our analyses suggest that current extrapolation approaches appear to be protective, and may often be very overprotective, but we have identified conditions in which this may not be the case. We recommend that additional consideration be given to the relative frequency of different life-cycle types, to the proportions of sensitive and insensitive taxonomic groups in communities, and to the role of density-dependent influences on population dynamics to ensure that we develop environmental quality criteria that are sufficiently--but not overly--protective.     

Medicalisation of food advertising. Nutrition and health claims in magazine food advertisements 1990–2008

Food advertising increasingly portrays food as a type of medicine. A content analysis of magazine food advertisements in 1990 through 2008 shows that this was manifested with time more in the (a) nutrition claims and (b) health claims made in food advertisements, as well as the (c) food groups and (d) media genres to which nutrition and health claims in food advertising pertained. This so-called “medicalisation” of food advertising may promote images of the body and mind as malfunctioning unless remedied by the use of – advertised – products.