Hair mercury levels in an urban population from southern Italy: fish consumption as a determinant of exposure

Mercury levels in hair of a general population, 237 adults aged between 35-45, in Naples, Italy, were assessed. The subjects were asked to fill in a questionnaire about age, gender, body weight, height, body mass index (BMI), fish consumption, number, surface and area of dental amalgam fillings. Total mercury (THg) concentrations in human hair ranged from 0.221 to 3.402 microg/g and the mean value for the subjects under study was 0.638 microg/g. Study participants were divided into three groups in accordance with fish consumption and dental amalgam: ANF (amalgam and no fish); NAF (no amalgam but with fish) and AAF (amalgam and fish). Significant differences in THg were found in the three groups (p<0.05). A multiple linear regression analysis showed a weak but significant correlation of THg content in hair with respect to gender and age, but almost no association was found between THg and dental fillings. Conversely, a strong correlation was obtained between THg and fish consumption regardless of the group evaluated. Finally, mercury levels in hair exceeded the levels corresponding to the EPA reference dose (RfD) of 0.1 microg Hg/kg body weight per day (1 microg Hg/g hair) in 6% of the population (4% men and 2% women). However, the THg limits in our subjects were not exceeded according to the WHO guidelines, which use a benchmark dose of 0.23 microg Hg/kg bw/day (14 microg Hg/g maternal hair).     

Exposure to organochlorines and mercury through fish and marine mammal consumption: Associations with growth and duration of gestation among Inuit newborns

BackgroundSeveral studies have reported negative associations of polychlorinated biphenyls (PCBs), hexachlorobenzene (HCB) and mercury (Hg) with duration of gestation and fetal growth in fish eating populations. Docosahexaenoic acid (DHA) from fish, seafood and marine mammal intake has been reported to be positively related with pregnancy duration and fetal growth. So far, it remains unclear, however, if the associations of environmental contaminants (ECs) with growth are direct or mediated through their relation with the duration of gestation and the degree to which DHA intake during pregnancy attenuates the negative association of ECs with fetal growth.ObjectivesTo investigate direct and indirect associations of in utero exposure to ECs with fetal growth and pregnancy duration while taking into account the possible positive effects of DHA.MethodsPregnant Inuit women (N = 248) from Arctic Quebec were recruited and cord blood samples were analyzed for PCBs, HCB, Hg and DHA. Anthropometric measurements were assessed at birth. Path models were used to evaluate direct and indirect associations.ResultsCord concentrations of PCB 153, HCB and Hg were significantly associated with shorter duration of pregnancy (β varying from − 0.17 to − 0.20, p < 0.05). Path models indicated that the associations of PCBs, HCB and Hg with reduced fetal growth (β varying from − 0.09 to − 0.13, p < 0.05) were mediated through their relations with shorter gestation duration. Cord DHA was indirectly related to greater growth parameters (β varying from 0.17 to 0.20, p < 0.05) through its positive association with gestation duration.ConclusionPrenatal exposure to ECs was associated with reduced gestation duration, which is a recognized determinant of fetal growth. DHA intake during pregnancy appeared to have independent positive association with fetal growth by prolonging gestation. Whether these associations are causal remains to be elucidated.     

Effect of toxic pollution on fish populations and mechanisms for maintaining population size

The effect of pollution on fish populations has been analyzed. It has been demonstrated that the strategy of the fish life cycle changes in the direction corresponding to r-selection. Smaller individuals that mature at an earlier age and are preadapted to energy allocation for maintaining a higher metabolic rate and activating detoxification gain a survival advantage under toxic conditions. If young females whose gametogenesis is within the normal range join the spawning stock, the population size is successfully maintained but its parameters and gene pool are changed.     

Distribution and concentration of PCB in the Hudson river and associated management problems

The Hudson River is contaminated with PCBs and a remedial program has been formulated by New York State in order to cope with this toxic pollutant. Over $3 million has been spent to document fully the extent of the PCB contamination in the Upper Hudson River. It appears that over 60% of the PCBs in the riverbed are contained within 40 so called “hot spot” areas, that is, those areas that have PCB concentrations greater than 50 ppm. After evaluating all alternatives, the PCB Reclamation Project was formulated which consists of mechanically or hydraulically dredging the 40 “hot spot” areas and placing the contaminated sediments in a encapsulated land burial facility. Such a facility would meet all federal and state criteria for PCBs disposal. New York is seeking to finance this remedial project through the use of federal funds, that could be obtained either through, the Clean Water Act or through special Congressional legislation or through the Superfund Bill, once it is enacted. The PCB Reclamation Project, if funded this spring, as is presently anticipated, could be completed ny 1983.     

Influence of climate on the atmospheric radiocarbon concentration

In this paper, the climate effect on the atmospheric radiocarbon concentration is estimated using the data, derived by using dendrochronologically dated tree ring samples, on sunspot number and global surface temperature during 1650–1800 A.D.; however, in order to use the data as a record of changes in radiocarbon production rate or cosmic ray intensity, the variations due to the geochemical process must be eliminated. The estimated influence of climate on the atmospheric radiocarbon concentration is 3–5 times greater than the direct contribution of the change of radiocarbon concentration through a Maunder minimum. The influence of climate on the atmospheric radiocarbon concentration through a transfer rate of CO₂ between atmosphere and ocean was estimated at a rate of −13% per degree.The elimination of variations caused by climate and sunspot activities from the variations in atmospheric radiocarbon concentration gives a long time scale trend having a minimum and maximum which occur in about the seventh century A.D. and the sixth millennium suggesting a good correlation between this trend of variation and paleogeomagnetic data.     

Persistent halogenated compounds in aquaculture environments of South China: implications for global consumers' health risk via fish consumption

This study examined the potential sources of persistent halogenated compounds (PHCs), including organochlorine pesticides, mainly DDXs (sum of o,p'- and p,p'-DDT, -DDD, and -DDE and p,p'-DDMU) and polybrominated diphenyl ethers, to typical aquaculture environments of South China, determined the relative importance of gill diffusion and fish feeding for exposure of fish to these contaminants and assessed potential health risk for global consumers via consumption of fish from South China. Fish feed is generally a direct and important source of PHCs in both freshwater and seawater aquaculture. In addition, gill diffusion is the predominant uptake route for PHCs (except p,p'-DDMU, o,p'-DDD and -DDT) in farmed freshwater fish, whereas accumulation from the diet is the major route for farmed marine fish. Risks to health of global consumers via consumption of fish from South China are minimal. However, increased risk can be foreseen due to continuous use of brominated fire retardants and electronic waste importation to China.     

Uptake and elimination of radiocaesium in fish and the "size effect."

A number of hypotheses have previously been developed concerning the rates of uptake and elimination of radiocaesium (137Cs) in fish. These include the influence of potassium and other water chemical parameters on both uptake and elimination, and the effect of fish size on accumulation. In order to test these hypotheses, we have assembled a data set comprising more than 1,000 measurements of radiocaesium (137Cs) in predatory fish (perch, pike and brown trout) in nine European lakes during the years after Chernobyl. These data have been analysed using simple models for uptake and excretion of 137Cs in fish, showing that: 1. Fish-water concentration factors (CF) were inversely proportional to potassium [K+] concentration of the different lakes, in agreement with previous studies. 2. The uptake rate of 137Cs in fish was negatively correlated with lake [K+], but excretion rate was independent of [K+]. 3. Lower than expected CF values were found in one lake, Iso Valkj?rvi, Finland. This is attributed to inhibition of the K+ (and therefore 137Cs) high affinity transport system in aquatic plants and fish by low pH and/or low Ca2+. 4. The inclusion of fish weight as a parameter in our dynamic model significantly improves the ability of the model to fit the observed measurements of 137Cs. 5. The model developed from the above hypotheses was able to fit the data from nine different lakes to within approximately a factor of 3 of the observed values.     

The plant/soil concentration ratio for calcium,radium, lead,and polonium: Evidence for non-linearity with reference to substrate concentration

Evidence exists from both the literature and our own observations that plant nuclide uptake for a variety of plants and elements is a non-linear function of substrate concentration. The uptake response to increasing substrate concentration is usually in the form of a single or multi-phasic saturation curve. For some plant types and elements the uptake response may also take the form in which a threshold of soil activity is necessary before uptake is measurable. We present a generic uptake response curve and the resulting concentration ratio function determined by computer simulation. Data describing the uptake response of plants to ²²⁶Ra, ²¹⁰Pb and ²¹⁰Po as well as for calcium and stable lead are discussed. Functions are also presented for these elements to describe the uptake response and the concentration ratio and their mathematical forms are compared to the generic model.     

Measured elemental transfer factors for boreal hunter/gatherer scenarios: fish, game and berries

The environmental assessment of long-term nuclear waste management requires data to estimate food chain transfers for radionuclides in various environmental settings. For key elements such as iodine (I) and chlorine (Cl), there is a paucity of transfer factor data, particularly outside of agricultural food chains. This study dealt with transfers of I, Cl and 28 other elements to foods that would be typical of boreal hunter/gatherer lifestyles, as well as being common foods for modern recreational and subsistence hunters. Food/substrate concentration ratios (CRs) and related transfer factors for eight species of widely distributed fish, whitetail deer (Odocoileus virginianus), Canada geese (Branta canadensis) and wild blueberries (Vaccinium myrtilloides) were measured and compared to the literature. Limited data were obtained for caribou (Rangifer tarandus), elk (Cervus elaphus) and moose (Alces americanus). Freshwater sediment Kd values and CRs for a ubiquitous freshwater macrophyte were also obtained. The CRs for I in fish were 29 L kg⁻¹ in edible muscle (fillets) of large-bodied species and 85 L kg⁻¹ for whole, small-bodied fish. The log CRs for fish and macrophytes were correlated across elements. For several elements, the Kds for sediments in deep water were ∼4-fold higher than for littoral samples. The elemental transfers to wild animals for some elements were notably different than the literature indicates for domestic animals. It is argued that the transfer data obtained using indigenous elements from real environmental settings, as opposed to contaminant elements in experimental or impacted environments, are especially relevant to assessment of long-term impacts.     

EPIC database on the effects of chronic radiation in fish: Russian/FSU data

The paper presents the extraction of data from the EPIC database, outlining the effects of chronic radiation exposure in fish. The EPIC database 'Radiation effects on aquatic biota' is compiled as part of the current EC Project EPIC (Environmental Protection from Ionizing Contaminants in the Arctic). The EPIC database is based on information from publications in Russian (Russian/former Soviet Union data). The data are focused on the effects in fish at relatively low doses of chronic radiation exposure. The effects are grouped by three key endpoints: morbidity, reproduction, and mortality/life shortening. A preliminary scale of dose-effects relationships for fish has been constructed.     

Influence of the zebra mussel and fish fry on structural and functional characteristics of microorganisms in experimental ecosystems

The interactions of zebra mussels, invertebrates, fish, and microorganisms were studied experimentally. Trends in the distribution of total bacterial biomass, the abundance of heterotrophic organisms, and their functional activities in water and grounds were analyzed. The most favorable conditions for development of bacteria developed in June, in the presence of fish and without zebra mussels. In experimental ecosystems with zebra mussels, a decrease in the abundance and activity of microorganisms and a change of dominant yeast forms were observed.     

Toxic effects of waterborne polychlorinated biphenyls and sex differences in an endangered goodeid fish (Girardinichthys viviparus)

Polychlorinated biphenyls (PCBs) elicit toxic effects in different species. PCBs undergo biotransformation by enzymes associated with the mixed functional oxidase system, such as cytochrome P450 (cyt P450), this biotransformation being sex-dependent. No other metabolic pathways are known, however, in connection with this process. Thus, the present study aims to evaluate the effects of waterborne PCBs at sublethal nominal concentrations (0.92 mg PCBs/L) on the black-fin goodeid Girardinichthys viviparus, an endangered fish native to the Valley of Mexico, as well as any sex differences related to PCB biotransformation. Eight-month-old adult fish born in the laboratory were exposed for 1, 2, 4, 8 and 16 days to half the LC(0) (calculated concentration at which no deaths occurred after 96 h) determined by an acute toxicity test. Specimens were sacrificed following exposure and the liver was used to evaluate different biomarkers: cyt P450 concentration and alcohol dehydrogenase (ADH) and ethoxyresorufin O-deethylase (EROD) activities. Results show sexual differentiation with regard to all biomarkers in both the control group and PCB-treated fish, with higher values found in males. The induction rate of cyt P450 remained constant throughout the study in males. In females, induction peaked on day 4, coinciding with maximum EROD activity, and fell significantly thereafter. EROD was lower in PCB-treated males than in the control group, but was greater in magnitude. ADH was significantly induced in both sexes from day 2 to day 16 of exposure. The highest response as compared to the control group occurred on day 8 in females. A correlation was found between ADH activity and exposure to PCBs. Three possible action mechanisms, operating either individually or concurrently, are proposed.     

Determination of toxic elements (mercury,cadmium, lead,tin and arsenic) in fish and shellfish samples. Risk assessment for the consumers

Although fish intake has potential health benefits, the presence of metal contamination in seafood has raised public health concerns. In this study, levels of mercury, cadmium, lead, tin and arsenic have been determined in fresh, canned and frozen fish and shellfish products and compared with the maximum levels currently in force. In a further step, potential human health risks for the consumers were assessed. A total of 485 samples of the 43 most frequently consumed fish and shellfish species in Andalusia (Southern Spain) were analyzed for their toxic elements content. High mercury concentrations were found in some predatory species (blue shark, cat shark, swordfish and tuna), although they were below the regulatory maximum levels. In the case of cadmium, bivalve mollusks such as canned clams and mussels presented higher concentrations than fish, but almost none of the samples analyzed exceeded the maximum levels. Lead concentrations were almost negligible with the exception of frozen common sole, which showed median levels above the legal limit. Tin levels in canned products were far below the maximum regulatory limit, indicating that no significant tin was transferred from the can. Arsenic concentrations were higher in crustaceans such as fresh and frozen shrimps. The risk assessment performed indicated that fish and shellfish products were safe for the average consumer, although a potential risk cannot be dismissed for regular or excessive consumers of particular fish species, such as tuna, swordfish, blue shark and cat shark (for mercury) and common sole (for lead).     

Fish consumption in pregnancy, cord blood mercury level and cognitive and psychomotor development of infants followed over the first three years of life: Krakow epidemiologic study

BACKGROUND: Although the maternal fish consumption is supposed to have beneficial effects on development of infants, it may be harmful for child cognitive development since fish is a common source of methylmercury. PURPOSE OF THE STUDY: Purpose of the study was to describe the usual pattern of fish consumption during pregnancy in Poland and explain the variability of prenatal mercury exposure due to fish intake by mothers. The other endpoint of the study was the assessment of the cognitive and psychomotor development of infants related to prenatal mercury exposure over the 3-year follow-up. MATERIAL AND METHODS: The study sample consisted of 374 infants born at 33-42 weeks of gestation between January 2001 and March 2003 to mothers attending ambulatory prenatal clinics in the first and second trimesters of pregnancy. Total mercury level in whole cord blood was measured and the Bayley Scales of Infant Development (BSID-II) was used to assess the mental (MDI) and psychomotor developmental index (PDI) in children at 12, 24 and 36 months of age. RESULTS: Self-reported weekly amount of fish consumption during the first two trimesters of pregnancy correlated positively with umbilical cord mercury concentrations (r(s)=0.22, p<0.0001). The corresponding correlation coefficient for the fish consumption in the third trimester of pregnancy was 0.21, p<0.0001. There was an inverse association between mercury exposure and both MDI (beta regression coeff.=-2.8, p=0.01) and PDI scores (beta coeff.=-2.3, p=0.04) at 12 months of age. Subsequent BSID-II testing at 24 and 36 months did not confirm significant association between exposure and cognitive or psychomotor function. The estimates of association between mercury prenatal exposure and the development of infants, which were based on the longitudinal analysis of all BSID-II measurements done in the follow-up (generalized estimating equations statistical model) showed that the performance deficit observed at 12 months of age was of border significance.     

Influence of atmospheric stability on the mass concentration and chemical composition of atmospheric particles: a case study in Rome, Italy

PM(10) concentration and chemical composition (ions and carbon compounds) at three sampling stations in Rome and in its surroundings was determined daily during a one-month field study, carried out during December 2003. PM concentration at the traffic station was considerably higher than at the urban background and semi-rural stations; elemental carbon was detected as one of the chemical components responsible for this increase. The difference in the concentration of sulphate and ammonium was negligible, as it was expected for secondary pollutants. A negative artefact in the determination of ammonium nitrate by means of heated automatic monitors was highlighted. The dilution properties of the lower atmosphere were traced by means of a natural radioactivity monitor. This parameter has been found to play an essential role in pollution buildup. A considerable increase in PM concentration was observed to coincide with periods of atmospheric stability. The main difference in PM composition between periods of high concentration and periods of "clean" air was found to be in the increase of ammonium nitrate concentration.     

Persistent organic pollutants in breast milk of mothers residing around an open dumping site in Kolkata,India: Specific dioxin-like PCB levels and fish as a potential source

Concentrations of persistent organic pollutants (POPs) such as polychlorinated dibenzo-p-dioxins (PCDDs), polychlorinated dibenzofurans (PCDFs), polychlorinated biphenyls (PCBs) and organochlorine pesticides were measured in human breast milk collected from mothers residing near an open dumping site and a reference site in Kolkata, India during 2004–2005. POPs were detected in all the human milk samples analyzed, suggesting that residents of Kolkata are widely exposed to these contaminants. Concentrations of dioxin-like PCBs in the samples from the dumping site were significantly higher than in the reference site samples, whereas no such difference was found for PCDDs and PCDFs. In addition, significantly higher concentrations of total PCBs were also observed in the samples from the dumping site than the reference site. Interestingly, concentrations of total and dioxin-like PCBs in the breast milk of mothers from the dumping site significantly increased with the number of years of residence near the dumping site. These results indicate that significant pollution sources of PCBs are present in the dumping site of Kolkata and the residents living around are exposed to relatively higher levels of PCBs. When the residue levels of dioxins and related compounds in fish collected from ponds near the Kolkata dumping site and the reference site were measured, it was found that dioxin-like PCB and TEQ levels in fish from the dumping site were notably higher than those from the reference site. This result indicates that fish is a potential source of PCBs for residents living near the Kolkata dumping site.     

Critical compilation and review of plant/soil concentration ratios for uranium,thorium and lead

The transfer of natural radionuclides of the U decay series through the biosphere is important, especially for assessment of the impacts of mining and milling of U ores. The pathway from soil through plants to humans can contribute significantly to the overall dose received from these radionuclides. Element-specific concentration ratios (CRs) used to model the impact of radionuclides have been reported for U, Th and Pb but have not received the research or critical review accorded other radionuclides associated with the nuclear industry. This paper compiles and analyses many of the available data on CRs for U, Th and Pb and recommends values appropriate for environmental assessments. A brief overview of the statistical properties of CR values and the complex soil/plant processes encompassed by this ratio is also given, as well as an overview of some of the physical, chemical and biological factors likely to influence CR values.Our analysis showed that CR values decreased significantly as the corresponding soil concentrations increased. Although the variability was substantial, with ranges of 1000- to 30 000-fold, CR values did differ significantly among some soil and plant types. The overall geometric means were 0·0045, 0·0036 and 0·052 for U, Th and Pb, respectively.     

Educating for sustainable production and consumption and sustainable livelihoods: learning from multi-stakeholder networks

This paper examines how education for sustainable development (ESD) can be concretely advanced using the theoretical approaches of sustainable consumption and production (SCP) and sustainable livelihoods (SL). Five case examples illustrate a diverse set of strategic educational interventions focusing on: (1) education of specific organizational actors about these theoretical frameworks illustrated with case examples (such as SCP training by the United Nations University Institute of Advanced Studies [UNU-IAS] and CSR-Asia of government and business representatives), (2) regional education strategies focused on production and consumption in specific sectors (such as the food sector in Sk?ne, Sweden), (3) social learning directed at innovation for sustainable development (such as competitions of solar boats developed by universities in the region of Friesland, the Netherlands), (4) education of consumers and firms made possible by the adoption of certification systems affirming SCP and SL (such as Cradle-to-Cradle certification of a paper company in the Netherlands or the establishment of Fair Trade cities in Sweden), or (5) reorienting communities to address underutilized productive physical capital within communities (such as the sharing productive capital project in rural areas of Saskatchewan, Canada). The cases are drawn from the projects that the UNU-IAS, four of its regional centers of expertise (RCE) on ESD and other affiliates have conducted. In addition to documenting the educational processes emerging from specific regions, the paper highlights findings related to the success of these projects and opportunities for further research, including regional and inter-regional approaches.     

Addressing food supply chain and consumption inefficiencies: potential for climate change mitigation

Globally, more than 30 % of all food that is produced is ultimately lost and/or wasted through inefficiencies in the food supply chain. In the developed world this wastage is centred on the last stage in the supply chain; the end-consumer throwing away food that is purchased but not eaten. In contrast, in the developing world the bulk of lost food occurs in the early stages of the supply chain (production, harvesting and distribution). Excess food consumption is a similarly inefficient use of global agricultural production; with almost 1 billion people now classed as obese, 842 million people are suffering from chronic hunger. Given the magnitude of greenhouse gas emissions from the agricultural sector, strategies that reduce food loss and wastage, or address excess caloric consumption, have great potential as effective tools in global climate change mitigation. Here, we examine the challenges of robust quantification of food wastage and consumption inefficiencies, and their associated greenhouse gas emissions, along the supply chain. We find that the quality and quantity of data are highly variable within and between geographical regions, with the greatest range tending to be associated with developing nations. Estimation of production-phase GHG emissions for food wastage and excess consumption is found to be similarly challenging on a global scale, with use of IPCC default (Tier 1) emission factors for food production being required in many regions. Where robust food waste data and production-phase emission factors do exist—such as for the UK—we find that avoiding consumer-phase food waste can deliver significant up-stream reductions in GHG emissions from the agricultural sector. Eliminating consumer milk waste in the UK alone could mitigate up to 200 Gg CO₂e year^?1; scaled up globally, we estimate mitigation potential of over 25,000 Gg CO₂e year^?1.     

Irish fish, Irish people: roles and responsibilities for an emptying ocean

Human decisions shape patterns of seafood resource use. Consequently, it is also these decisions made by actors within seafood industries which ultimately determine the environmental impact of fisheries resource extraction from marine environments. In this study, we investigated the roles and influences of various actors within the Irish seafood industry. Our objectives were to learn more about the working dynamics of the industry and identify possibilities for improvements towards industry sustainability. We employed qualitative research methods including semi-structured interviews, focus groups and participant observation to access information from Irish consumers, retailers, wholesalers, scientists and key industry informants. The diversity of seafood products available within the Irish market is generally low. However, consumers who experiment with trying new varieties of seafood are influenced by dining experiences at restaurants or while travelling abroad as well as through cooking shows or cookbooks. Potential for influence on factors including consumer choice, stocking and sourcing decisions, business management and fisheries policy was found within all levels of the seafood industry, though a sense of responsibility in the context of seafood sustainability was less common. In addition, the absence of shortages within the Irish market due to imports, aquaculture and mislabelling appears to be preventing widespread acceptance about claims of overfishing. It is clear that ultimately, responsible policy decisions and effective enforcement will be needed to improve the overall sustainability of the industry. However, pressure for positive change can come from all actors that prioritise sustainability as the most important objective for future industry operation.