Levels of PCDD/PCDFs and PCBs in edible marine species and human intake: a literature review

Why and How Meet n-3 PUFA Dietary Recommendations?

Obesity and the metabolic syndrome are systemic inflammatory diseases reaching epidemic proportions. Contemporary changes in human nutrition occurred characterized by increased consumption of fat and of vegetable oils rich in n-6 polyunsaturated fatty acids (PUFAs) together with decrease in n-3 PUFA-rich foods, resulting in an n-6/n-3 ratio of 10–20/1 in Western diet for a ratio around 1/1 in the diet of our ancestors. The literature provides compelling evidence for the health benefit of n-3 PUFA consumption on inflammation and metabolic syndrome prevention and treatment. Such evidence led to the establishment of comprehensive recommendations. However, we show here that, both in collective catering proposed to children and in hospital diet, it is not straightforward to meet such recommendations. Willingness of governments to institute changes, with accountable decisions on catering, nutritional education, and food processing, is required to face our neglected responsibility in promoting balanced diet and consumption of foods rich in essential nutrients in the general population.

Differential long-term effects of developmental exposure to polychlorinated biphenyls 52, 138 or 180 on motor activity and neurotransmission. Gender dependence and mechanisms involved

Developmental exposure to polychlorinated biphenyls (PCBs) induces motor alterations in humans by unknown mechanisms. It remains unclear whether: (a) all non-dioxin-like (NDL) PCBs are neurotoxic or it depends on the grade of chlorination; (b) they have different neurotoxicity mechanisms; (c) they affect differently males and females. The aims of this work were to assess: (1) whether perinatal exposure to 3 NDL-PCBs with different grades of chlorination, (PCBs 52, 138 or 180) affects differentially motor activity in adult rats; (2) whether the effects are different in males or females and (3) the mechanisms involved in impaired motor activity. Rats were exposed to PCBs from gestational day 7 to post-natal day 21. Experiments were performed when the rats were 4 months-old. PCB52 did not affect motor activity, PCB180 reduced it in males but not in females and PCB138 reduced activity both in males and females. PCB52 or 138 did not affect extracellular dopamine in nucleus accumbens (NAcc). PCB180 increased it both in males and females. Extracellular glutamate in NAcc was reduced by the three PCBs. Activation of metabotropic glutamate receptors (mGluRs) in NAcc increased extracellular dopamine in control rats and in those exposed to PCB52 and reduced dopamine in rats exposed to PCB180. In rats exposed to PCB138 activation of mGluRs increases dopamine in females and reduces it in males. The opposite changes were observed for glutamate. mGluRs activation reduced extracellular glutamate in control rats and in those exposed to PCB52 and increased glutamate in rats exposed to PCB180. In rats exposed to PCB138 activation of mGluRs reduces glutamate in females and increases it in males. The data support that different NDL-PCBs affect differently motor activity. Increased glutamate release in NAcc following activation of mGluRs would be involved in reduced dopamine release and reduced motor activity in rats exposed to PCB138 or 180.

Concentrations and determinants of organochlorine levels among pregnant women in Eastern Spain

Persistent organic pollutants (POPs) comprise a large variety of toxic substances with ample distribution. While exposure to these toxins occurs mainly through diet, maternal POP levels may be influenced by certain sociodemographic, environmental, or lifestyle factors. This is important given that these substances may have adverse effects on fetal development. The aim of this study is to examine the sociodemographic, environmental, lifestyle, and dietary determinants of the levels of hexachlorobenzene (HCB), b-hexachlorocyclohexane (b-HCH), 1,1,1-trichloro-2,2-bis(4-chlorophenyl)ethane (4,4'-DDT), 1,1-dichloro-2,2-bis(4-chlorophenyl)ethylene (4,4'-DDE), and polychlorinated biphenyls (PCB congeners 118, 138, 153, 180) measured in the blood of pregnant women participating in a mother-child cohort study conducted in Valencia (Spain). The study population consisted of 541 pregnant women who formed part of the INMA (Childhood and the Environment) cohort (2004-2006). POP levels were determined in blood taken during the 12th week of pregnancy with the aid of gas chromatography with electron capture detection. Sociodemographic, environmental, and dietary information was obtained from a questionnaire. Multivariate Tobit regression models were constructed in order to assess the association between POP levels and selected covariates. The results showed that all the women had detectable levels of at least one of these compounds while in 43% of the subjects, all eight compounds were detected. The compounds found in the greatest number of women were 4,4'-DDE (100%) and PCBs 153 and 180 (95%). The most important determinants of high POP levels were the mother's age, country of origin, increased body mass index, and number of weeks of breastfeeding after previous pregnancies. With regard to diet, 4,4'-DDT and 4,4'-DDE levels increased with the intake of meat, fruit, and cereal. PCB 153 levels increased with the intake of seafood. The levels of HCB, b-HCH, 4,4'-DDT, and 4,4'-DDE observed in this study were slightly higher than in other studies, whereas the PCB levels were similar.

Recombinant human AhR-mediated GUS reporter gene assays for PCB congeners in transgenic tobacco plants in comparison with recombinant mouse and guinea pig AhRs

Four expression plasmids for recombinant human aryl hydrocarbon receptor (hAhR) consisting of a ligand binding domain of hAhR, a DNA-binding domain of LexA and a transactivation domain of VP16 as well as β-glucuronidase (GUS) reporter genes were constructed. All the expression plasmids were transformed into tobacco plants. The selected transgenic tobacco plants were used to assay. PCB congeners showed GUS activity in a TEF-dependent manner. The selected transgenic tobacco plant XhD4V17 was compared with the transgenic tobacco plants XmD4V26 and XgD2V23 containing recombinant mouse (m) AhR-mediated GUS reporter gene expression cassette and recombinant guinea pig (g) AhR-mediated GUS reporter gene expression cassette for PCB congener-inducible GUS activity. The data revealed that the tobacco plant XgD2V23 was the most active in PCB congener-inducible GUS activity. In a 1:1 mixture of PCB126 and PCB80 a reduced PCB126-induced GUS activity was observed in plant XgD2V23, which could possibly be due to interaction between PCB126 and PCB80.

Developmental exposure to TCDD reduces fertility and negatively affects pregnancy outcomes across multiple generations

TCDD (2,3,7,8-tetrachlorodibenzo-p-dioxin) is a ubiquitous environmental contaminant and known endocrine disruptor. Since humans and animals are most sensitive to toxicant exposure during development, we previously developed a mouse model of in utero TCDD exposure in order to examine the impact of this toxicant on adult reproductive function. Our initial in utero toxicant-exposure study revealed a dose-dependent reduction in uterine sensitivity to progesterone; however, we did not previously explore establishment or maintenance of pregnancy. Thus, in the current study, we examined pregnancy outcomes in adult C57BL/6 mice with a history of developmental TCDD exposure. Herein we demonstrate reduced fertility and an increased incidence of premature birth (PTB) in F1 mice exposed in utero to TCDD as well as in three subsequent generations. Finally, our studies revealed that mice with a history of developmental TCDD exposure exhibit an increased sensitivity to inflammation which further negatively impacted gestation length in all generations examined.

Mercury and polychlorinated biphenyls in Asian market fish: a response to results from mercury biomonitoring in New York City

In 2004, the New York City (NYC) Health and Nutrition Examination Survey measured the highest blood mercury levels in Asian and foreign-born Chinese demographic groups. Fish consumption was the strongest predictor of exposure. The survey did not inquire about consumption of individual species, and subsequent visits to fish markets serving the Asian community suggested that many popular species lack contaminant data. Our objective was to supplement existing information on contaminants in commercial fish by collecting data on species present in markets serving the Asian community. We measured total mercury and the sum of 101 polychlorinated biphenyl (PCB) congeners in 282 individual specimens of 19 species or products from retail fish markets in Chinese neighborhoods in NYC. Species were selected based on their volume in the market, and an absence or insufficiency of national data on mercury levels. PCBs were measured because they are also contaminants of concern. All measurements were made on a wet weight basis on whole fillets (with skin) or products (drained of liquid). Mean mercury levels ranged from below the limit of detection (0.004microg/g) in tilapia to 0.229microg/g in tilefish. The highest mercury level (1.150microg/g) was measured in a tilefish specimen, and mercury levels in tilefish increased with the specimen size. Mean PCB levels ranged from 1ng/g in red snapper to 98ng/g in buffalo carp. The highest PCB levels were measured in a buffalo carp (469ng/g) and a yellow croaker (495ng/g). Species-specific differences in PCB levels accounted for only 6.3% of total variability, in contrast with 39.2% for mercury. Although we did not measure high mean mercury levels in the species we sampled, frequent consumption of fish with low to moderate levels can also elevate blood mercury. The data we collected can be used to guide fish consumption in Asian communities. However, risk-benefit trade-offs also need to be considered.

Multivariate models to predict human adipose tissue PCB concentrations in Southern Spain

The use of Polychlorinated biphenyls (PCBs) has been severely restricted due to their high toxicity and persistency in the environment. However, the presence of PCBs in human tissues nowadays is still been reported worldwide. Background exposure predictors of the human PCB body burden require more precise understanding. In the present study, PCB congeners 138, 153, and 180 were quantified in adult adipose tissue samples (n=387) from Granada Province (Southern Spain) and data on potential predictors of PCB concentrations were gathered by questionnaire. Chemical analysis of the selected congeners was done by gas chromatography and mass spectrometry, and multivariate analyses were performed stratifying by gender. PCB residues were quantified in 92% (PCB 153), 90% (PCB 180), and 86% (PCB 138) of the population. Geometric mean concentrations were 161.65+/-4.41 ng/g lipid for PCB 153, 111.62+/-6.27 ng/g lipid for PCB 180, and 38.41+/-8.61 ng/g lipid for PCB 138. Multivariate models explained 30-36% of the variability in PCB concentrations. Age and body mass index (BMI) predicted exposure in both males and females and were positively correlated with the concentration of the three PCB congeners. Occupation and diet predicted exposure in the males, whereas only dietary predictors were observed in the females. Further in-depth studies are required to investigate the influence of dietary habits on the bioaccumulation of PCBs and to evaluate the impact of policies aimed at reducing human exposure.

Perinatal exposure to polychlorinated biphenyls alters social behaviors in rats

Perinatal exposure to polychlorinated biphenyls (PCBs) leads to significant alterations of neural and hormonal systems. These alterations have been shown to impair motor and sensory development. Less is known about the influence of PCB exposure on developing emotional and motivational systems involved in social interactions and social learning. The present study examined the impact of perinatal PCB exposure (mixture of congeners 47 and 77) on social recognition in juvenile animals, conspecific-directed investigation in adults and on neural and hormonal systems involved in social functions. We used a standard habituation-dishabituation paradigm to evaluate juvenile recognition and a social port paradigm to monitor adult social investigation. Areal measures of the periventricular nucleus (PVN) of the hypothalamus were obtained to provide correlations with related hormone and brain systems. PCB exposed rats were significantly impaired in social recognition as indicated by persistent conspecific-directed exploration by juvenile animals regardless of social experience. As adults, PCB exposure led to a dampening of the isolation-induced enhancement of social investigation. There was not a concomitant alteration of social investigation in pair-housed PCB exposed animals at this stage of development. Interestingly, PVN area was significantly decreased in juvenile animals exposed to PCB during the perinatal period. Shifts in hypothalamic regulation of hormones involved in social behavior and stress could be involved in the behavioral changes observed. Overall, the results suggest that PCB exposure impairs context or experience-dependent modulation of social approach and investigation. These types of social-context deficits are similar to behavioral deficits observed in social disorders such as autism and other pervasive developmental disorders.

Levels of polychlorinated biphenyls (PCBs) and three organochlorine pesticides in fish from the Aleutian Islands of Alaska

BACKGROUND

Persistent organic pollutants (POPs), including polychlorinated biphenyls (PCBs) and chlorinated pesticides, have been shown to have many adverse human health effects. These contaminants therefore may pose a risk to Alaska Natives that follow a traditional diet high in marine mammals and fish, in which POPs bioaccumulate.

METHODS AND FINDINGS

This study examined the levels of PCBs and three pesticides [p, p'-DDE, mirex, and hexachlorobenzene (HCB)] in muscle tissue from nine fish species from several locations around the Aleutian Islands of Alaska. The highest median PCB level was found in rock sole (Lepidopsetta bilineata, 285 ppb, wet weight), while the lowest level was found in rock greenling (Hexagrammos lagocephalus, 104 ppb, wet weight). Lipid adjusted PCB values were also calculated and significant interspecies differences were found. Again, rock sole had the highest level (68,536 ppb, lipid weight). Concerning the PCB congener patterns, the more highly chlorinated congeners were most common as would be expected due to their greater persistence. Among the pesticides, p, p'-DDE generally dominated, and the highest level was found in sockeye salmon (Oncorhynchus nerka, 6.9 ppb, wet weight). The methodology developed by U.S. Environmental Protection Agency (USEPA) was used to calculate risk-based consumption limits for the analyzed fish species. For cancer health endpoints for PCBs, all species would trigger strict advisories of between two and six meals per year, depending upon species. For noncancer effects by PCBs, advisories of between seven and twenty-two meals per year were triggered. None of the pesticides triggered consumption limits.

CONCLUSION

The fish analyzed, mainly from Adak, contain significant concentrations of POPs, in particular PCBs, which raises the question whether these fish are safe to eat, particularly for sensitive populations. However when assessing any risk of the traditional diet, one must also consider the many health and cultural benefits from eating fish.

Dietary intake of fish, omega-3, omega-6 polyunsaturated fatty acids and vitamin D and the prevalence of psychotic-like symptoms in a cohort of 33,000 women from the general population

BACKGROUND

Low intake of fish, polyunsaturated fatty acids (PUFA) and vitamin D deficiency has been suggested to play a role in the development of schizophrenia. Our aim was to evaluate the association between the intake of different fish species, PUFA and vitamin D and the prevalence of psychotic-like symptoms in a population-based study among Swedish women.

METHODS

Dietary intake was estimated using a food frequency questionnaire among 33,623 women aged 30-49 years at enrollment (1991/92). Information on psychotic-like symptoms was derived from a follow-up questionnaire in the years 2002/03. Participants were classified into three predefined levels: low, middle and high frequency of symptoms. The association between diet and psychotic-like symptoms was summarized in terms of relative risks (RR) and corresponding 95% confidence intervals and was evaluated by energy-adjusted multinomial logistic regression.

RESULTS

18,411 women were classified as having a low level of psychotic-like symptoms, 14 395 as middle and 817 as having a high level. The risk of high level symptoms was 53% (95% CI, 30-69%) lower among women who ate fish 3-4 times per week compared to women who never ate fish. The risk was also lower for women with a high intake of omega-3 and omega-6 PUFA compared to women with a lower intake of these fatty acids. The effect was most pronounced for omega-6 PUFAs. The RR comparing the highest to the lowest quartile of omega-6 PUFAs intake was 0.78 (95% CI, 0.64-0.97). The associations were J-shaped with the strongest reduced risk for an intermediate intake of fish or PUFA. For fatty fish (herring/mackerel, salmon-type fish), the strongest inverse association was found for an intermediate intake (RR: 0.81, 95% CI, 0.66-0.98), whereas a high intake of fatty fish was associated with an increased risk of psychotic-like symptoms (RR: 1.90, 95% CI, 1.34-2.70). Women in the highest compared with the lowest quartile of vitamin D consumption experienced a 37% (95% CI, 22-50%) lower risk of psychotic-like symptoms.

CONCLUSION

Our findings raise a possibility that adult women with a high intake of fish, omega-3 or omega-6 PUFA and vitamin D have a lower rate of psychotic-like symptoms.

Dietary intake of PCDD/Fs and dioxin-like PCBs of the Belgian population

The World Health Organization recommends assessing human exposure to contaminants on a regular basis. In order to assess the current dietary exposure of the Belgian adult population to PCDD/Fs and dioxin-like PCBs and to update exposure estimates of 2000-2001, a total diet study was designed. The mean dietary intake of PCDD/Fs and dioxin-like PCBs in the Belgian adult population in 2008 was estimated to be 0.72pgTEQkgbw(-1)d(-1) (middle bound concentrations, TEF of 1998) based on occurrence data of 2008 and national food consumption data of 2004. This value is clearly below the Tolerable Weekly Intake (TWI) of 14pgTEQkgbw(-1)week(-1) set by the Scientific Committee on Food of the European Commission and below the provisional tolerable monthly intake of 70pgTEQkgbw(-1)month(-1) set by the Joint FAO/WHO Expert Committee on Food Additives. Considering the cumulative distribution, the intake was less than 1pgTEQkgbw(-1)d(-1) for more than 80% of the population, and less than 2pgTEQkgbw(-1)d(-1) for the entire population. When using the 2005 TEF instead of the 1998 TEF, the mean dietary intake in the Belgian adult population was estimated to be 0.61pgTEQkgbw(-1)d(-1).

Comparison of stable isotope composition and inorganic and organic contaminant levels in wild and farmed bluefin tuna, Thunnus thynnus, in the Mediterranean Sea

Stable isotope composition (delta(13)C and delta(15)N) and persistent pollutants, including heavy metals (Hg, Cd, Pb, As, Cu, Zn) and organochlorine compounds (PCBs, HCB and p,p'-DDE), were measured in muscle and liver tissues of wild and farmed bluefin tuna to investigate the changes occurring during the farming period and to assess the quality, in terms of contaminants, of the final product. At the end of farming, the food supplied was clearly integrated into the tuna tissues as derived from stable isotope signatures, and, contrarily to the literature findings obtained for other species, farmed tuna showed slight variations in persistent elements and chemical compounds in comparison with wild fish. The low tissue turnover of long-lived adult tuna together with the short farming period appeared to act to preserve the initial low contamination levels in the absence of new, elevated contamination sources (feed and environment), determining an acceptable quality of the final aquaculture product.

The aryl hydrocarbon receptor: regulation of hematopoiesis and involvement in the progression of blood diseases

The aryl hydrocarbon receptor (AhR) is a basic helix-loop-helix protein that belongs to the superfamily of environment-sensing PAS (Per-ARNT-Sim) proteins. A large number of ligands have been described to bind AhR and promote its nuclear translocation. In the nucleus, the AhR and its dimerization partner the AhR nuclear translocator (ARNT) form a DNA-binding complex that acts as a transcriptional regulator. Animal and human data suggest that, beyond its mediating responses to xenobiotic and/or unknown endogenous ligands, the AhR has a role, although as yet undefined, in the regulation of cell cycle and inflammation. The AhR also appears to regulate the hematopoietic and immune systems during development and adult life in a cell-specific manner. While accidental exposure to xenobiotic AhR ligands has been associated with leukemia in humans, the specific mechanisms of AhR involvement are still not completely understood. However, recent data are consistent with a functional role of the AhR in the maintenance of hematopoietic stem and/or progenitor cells (HSCs/HPCs). Studies highlighting AhR regulation of HSCs/HPCs provide a rational framework to understand their biology, a role of the AhR in hematopoietic diseases, and a means to develop interventions for these diseases.

Muscular cholinesterase activities and lipid peroxidation levels as biomarkers in several Mediterranean marine fish species and their relationship with ecological variables

Muscular cholinesterase activities, as potential markers of neurotoxic exposure, and lipid peroxidation levels, indicative of oxidative stress damage, both currently used in early-warning pollution monitoring, were characterised in eighteen fish species of ecologic and/or economic importance. These species comprise five orders and eleven families of teleosts and two species of elasmobranchs, feed using different strategies (benthic, epibenthic, endobenthic and pelagic), belong to different trophic levels and express different swimming behaviour. Their habitat ranges from 50 to 60 m (shallow or continental shelf) and 600 to 850 m (middle continental slope). Sampling took place in front of the Barcelona coast (NW Mediterranean) during four seasonal cruises in 2007. In the summer sampling, another site potentially exposed to a different pollution load (Vilanova) was included for comparison. Species, seasonal and site differences were tested and discussed in relation to chemical analysis of the local sediment, systematic position, habitat depth, feeding strategy, trophic level and swimming activity. Greater inter species differences rather than seasonal or site trends were seen in accordance to little pollution fluctuations. Higher cholinesterase activities were recorded in suprabenthos feeders, regardless of depth habitat, whereas LP levels were similar in all species except for the shark Scyliorhinus canicula in which they were consistently elevated. This study confirms and broadens former observations carried out with a more reduced number of fish species (Solé et al., 2008a).

Dioxin and endometrial progesterone resistance

Development of endometriosis likely requires multiple, interactive mechanisms involving both the endocrine and immune systems. Environmental toxicants, such as 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD), are of particular interest as potential contributory agents in the development of this disease because they can disrupt both systems. Nevertheless, defining the potential role that environmental exposure to TCDD plays in the development of endometriosis requires a better understanding of how this toxicant affects the biological processes that promote the disease. Although the disease mechanism(s) responsible for progesterone resistance in the endometrium of endometriosis patients remains speculative, our studies indicate that developmental exposure of mice to TCDD leads to a progesterone-resistant phenotype in adult animals that can persist for several generations. These studies and others underscore the importance of developing a greater understanding of the mechanisms of TCDD action that relate to reproductive disorders such as endometriosis.

Toxic emissions from crematories: a review

In recent years, the cremation ratio of cadavers has increased dramatically in many countries. Crematories have been identified as sources of various environmental pollutants, being polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs), and mercury those raising most concern. In contrast to other incineration processes for which the number of studies on their toxic emissions is considerable, references related to PCDD/F and mercury emissions from crematories and their health risks are very limited. In this paper, the scientific information concerning these issues, using the databases PubMed, Scopus and Scirus, is reviewed. Results show that in comparison with PCDD/F emissions from other sources, those corresponding to crematories are significantly lower, while those of mercury should not be underrated.

Polybrominated and mixed brominated/chlorinated dibenzo-p-dioxins in sponge (Ephydatia fluviatilis) from the Baltic Sea

Polybrominated dibenzo-p-dioxins (PBDDs) have recently been found in the Baltic Sea at concentrations 1000 times above that of the chlorinated analogs (PCDDs), yet their sources are undefined. Marine production of organobrominated compounds by sponges is well documented. The objective of the current study was to investigate the potential for an aquatic sponge (Ephydatia fluviatilis), common to the Baltic Sea, to produce PBDDs and other organobromine compounds in the field. Mono- to pentaBDDs as well as several mixed brominated/chlorinated dibenzo-p-dioxins (Br/Cl-DDs), PCDDs and methoxylated polybrominated diphenyl ethers (MeO-PBDEs) were quantified in sponge from the SW Baltic. Concentrations of individual PBDDs in the range 1-80 ng per g extractable organic matter were similar as in blue mussels from the Baltic Sea and about 25 000 times higher than 2,3,7,8-tetraCDD. To the best of our knowledge, this is the first time Br/Cl-DDs are reported in biota from a background environment. While this study does not point out sponges as a dominant source, the concentrations of PBDDs in sponge relative to related anthropogenic compounds such as PBDEs and PCDDs as well as the relative abundance of brominated dioxins and furans strengthens the idea of natural production.

Levels and congener profiles of PCDD/Fs, PCBs and PBDEs in seafood from China

A nationwide investigation into polychlorinated dibenzo-p-dioxins/furans (PCDD/Fs), polychlorinated biphenyls (PCBs), and polybrominated diphenyl ethers (PBDEs) in market seafood was conducted for the first time in this study. Total PCDD/F concentrations in fatty fish ranged from 0.13 to 8.64 pg g(-1) wet weight (mean 2.05 pg g(-1) wet weight), total PCB concentrations ranged from 38.9 to 3514 pg g(-1) wet weight (mean 1133 pg g(-1) wet weight), and total PBDE concentrations ranged from 42.8 to 913 pg g(-1) wet weight (mean 322 pg g(-1) wet weight). Corresponding mean toxicity equivalent (TEQ) values for total PCDD/F and dioxin-like PCB were 0.25 pg g(-1) wet weight (WHO 98-TEQ) and 0.32 pg g(-1) wet weight (WHO 98-TEQ), respectively. OCDD, PCB-138 and PBDE-47 were the dominant compounds according to their respective congeners. WHO 98-TEQ (PCDD/PCDF/PCB) for fatty fish and shell fish were 0.60 and 0.070 pg g(-1) wet weight, respectively, lower than the standard set by the European Commission. The contamination levels and profiles were compared with those documented in previous publications.

Stable isotope-guided analysis of congener-specific PCB concentrations in a Japanese coastal food web

Organisms collected from a coastal ecosystem in Japan were analyzed for concentrations of 205 polychlorinated biphenyls (PCBs) congeners; analyses were guided by delta(13)C and delta(15)N measurements. The regression slopes of log PCB concentration on delta(15)N value are regarded as indices of biomagnification in food webs. The slope (wet weight basis) of SigmaPCBs was +0.104; the slope (lipid weight basis) was close to zero. Lipid content increased from 0.06% in a primary producer to 8.32% in the highest trophic level consumer. Hence, biomagnification of SigmaPCBs (wet weight basis) can be attributed to increase of lipid content through the food web. For most of the congeners, the slopes (wet weight basis) exceeded those (lipid weight basis) by ca. 0.10. Slopes increased with increasing PCB chlorination levels between chlorine numbers 1-6; slopes decreased at higher chlorination levels. This decrease is likely caused by a decrease in membrane permeability with increasing molecular weight.

Solubility-enhanced electrokinetic movement of hexachlorobenzene in sediments: a comparison of cosolvent and cyclodextrin

Though solubility-enhanced electrokinetics (EK) has been investigated in remediation of soils contaminated with hydrophobic organic chemicals (HOCs), few comparative studies were performed regarding the effect of varied solubilizing agents on both EK parameters and contaminant removal. In this study, performances of two solubilizing agents, ethanol and methyl-beta-cyclodextrin (MCD), were compared in terms of either EK parameters or enhancement of hexachlorobenzene (HCB) movement in real contaminated sediments. Six bench-scale EK tests were conducted under a voltage gradient of 2V cm(-1) for 14 or 21 d. Results reveal that ethanol had a more negative effect on cumulative electroosmotic flow (EOF) than MCD. Furthermore, the distribution of ethanol in the sediment upon the completion of EK tests was lower than that of MCD. The movement of HCB in sediments was observed to increase with increasing concentrations of ethanol or MCD. Test with 50% ethanol exhibited the highest performance, followed by test with 50 g L(-1) MCD. The different performance of HCB removal for tests with varied solubilizing agents was found to be a combined effect of the distribution of solubilizing agents in sediments, the dissolution of HCB by pore liquid and the quantity of cumulative EOF. Finally, an integrated consideration of both EK parameters and contaminant removal suggests that MCD can perform better than ethanol for a long-term field application.

Polychlorinated biphenyls in Spanish adults: determinants of serum concentrations

BACKGROUND

Polychlorinated biphenyls (PCBs) are persistent compounds that may pose an environmental hazard to humans, food being the main source of exposure for the general population.

OBJECTIVE

To measure the serum concentrations of the main PCBs in subjects from the general population in Spain, and to assess potential determinants of such concentrations.

METHODS

Serum was obtained from blood samples of 953 subjects aged 35-64 years, residents in five Spanish regions (three from the North and two from the South), randomly selected from the EPIC-Spain cohort. Blood collection took place during 1992-1996 and four PCB congeners (118, 138, 153 and 180) were determined by means of gas chromatography with electron-capture detection (GC-ECD).

RESULTS

The concentration of total PCBs was 459 ng/g lipids (or 3.1 microg/l); the corresponding figures for PCB 153 were 186 ng/g lipids and 1.25 microg/l. Men had higher values than women, PCB levels increased with age, and serum concentration of PCBs was higher in northern regions. Body mass index (BMI) was inversely related to PCB concentrations, and fish intake was the dietary factor showing the greatest association with serum PCBs. The pattern described was similar for each congener separately.

CONCLUSIONS

We found concentrations similar to those reported in European countries where blood collection was carried during the same period. Regional differences within Spain are not fully explained by anthropometric or dietary factors. The inverse association with BMI suggests that in the mid-1990s there was still ongoing or recent exposure to PCBs in Spain.

Maternal exposure to dioxin disrupts gonadotropin production in fetal rats and imprints defects in sexual behavior

2,3,7,8-Tetrachlorodibenzo-p-dioxin (TCDD) and related substances are a class of environmental pollutants with suspected toxic effects on reproductive and developmental processes. This study investigated a hypothesis that maternal exposure to TCDD damages gonadotropin-regulated steroidogenesis in fetal gonads to imprint defects in sexual behavior as well as the maturation of gonadal tissues. Oral administration of 1 microg/kg TCDD to pregnant Wistar rats at gestational day (GD) 15 attenuated the expression of luteinizing hormone (LH), a regulator of gonadal steroidogenesis, in the pituitaries of male and female fetuses at GD20. TCDD treatment also reduced the fetal expression of testicular and ovarian steroidogenic proteins, including steroidogenic acute-regulatory protein. These changes in pituitary and gonadal proteins were fetus-specific, and this seems not to be because of the greater delivery of TCDD to the brain of fetuses than adults. This is because a reduction in LH production was not reproduced even although TCDD was administered intraventricularly to adult rats. Direct supplementation of equine chorionic gonadotropin (eCG), an LH-mimicking hormone, to TCDD-exposed fetuses at GD17 restored the reduced expression of gonadal steroidogenic proteins. Maternal exposure to TCDD delayed the development of gonadal tissues in male and female pups and impaired their sexual behavior. However, eCG treatment at the fetal stage again restored not only tissue maturation but also many of the behavioral defects that occurred at adulthood. These results demonstrate that TCDD disrupts steroidogenesis in fetuses by targeting pituitary gonadotropin production and imprints demasculinization in males and defeminization in females in terms of their copulatory behavior.

Enantiomeric signatures of chiral organochlorine pesticides in consumer fish from South China

Despite the importance of chiral organochlorine pesticide enantiomers in terms of environmental effects, no relevant data have been acquired in consumer fish. The present study determined the residual levels and enantiomer fractions (EFs) of α-HCH, o,p'-DDT, and o,p'-DDD in 11 consumer fish species from South China, including 6 freshwater farmed fish, 3 seawater farmed fish, and 2 wild marine fish. The mean concentrations of α-HCH, o,p'-DDT, and o,p'-DDD were 0.27, 4.4, and 3.5 ng/g wet, respectively, in all fish samples measured (n = 125). The EFs of α-HCH varied widely, from below the racemic EF of 0.5 to above it. For o,p'-DDT, the (+)-enantiomer dominated in all fish species. On the other hand, all EFs of o,p'-DDD, a metabolite of o,p'-DDT, were below 0.5, suggesting the (-)-enantiomer was preferentially enriched in fish. In addition, all three target analytes showed species dependence of EFs, consistent with results from other previous studies. Moreover, no significant correlations were found between the EFs and concentrations of α-HCH, o,p'-DDT, and o,p'-DDD in red drum, snubnose pompano, and crimson snapper, with the exception of o,p'-DDD in snubnose pompano, in which weak correlations were detected. Nevertheless, more studies are needed to explore the residual levels and toxicity of chiral contaminants in consumer fish or other foodstuff to further develop the human risk assessment framework based on chiral signatures.

Multi-residue analysis and ultra-trace quantification of 36 priority substances from the European Water Framework Directive by GC-MS and LC-FLD-MS/MS in surface waters

A multi residue analysis was developed for screening, quantification and confirmation of 36 priority organic compounds included in the 2000/60/EC European Water Framework Directive. The compounds analyzed included 19 pesticides, 8 PAH, 5 endocrine-disruptors and 4 organochlorine compounds. The method was developed in three steps. First, automated off-line solid-phase extraction using Strata X cartridges was optimized to trap simultaneously the 36 studied compounds. Second, the more volatile compounds were analysed by gas chromatography coupled to mass spectrometry with electron impact ionisation in selected ion monitoring mode (SIM). Third, the last 20 compounds were detected and quantified, in one run, by liquid chromatography coupled to fluorescence detector and tandem mass spectrometry. The excellent selectivity and sensitivity allowed us satisfactory quantification and confirmation at levels as low as 0.2-67 ng L(-1) with recoveries between 59 and 105%. Such methodology was then applied to French surface waters: all the waters present organic contaminants, and their concentration varied according to the origin and nature of substances.

Fish products available in Polish market--assessment of the nutritive value and human exposure to dioxins and other contaminants

Chemical analyses were performed on one hundred and twenty of the most popular varieties of fish products (smoked fish, salted fish, and marinated fish) of the fish market in Poland. The contents of the nutritive substances of fish products (protein, micro- and macronutrients, vitamins A(1), D(3), E, and fatty acids) and the chosen contaminant (toxic metals--mercury, cadmium, lead, arsenic; dioxin/furans--PCDDFs; dioxin-like PCB--dl-PCBs; seven congeners of polybrominated diphenyl ethers--PBDEs; organochlorine pesticides--SigmaDDT, HCB, SigmaHCH and marker polychlorinated biphenyls--PCB(7)) levels were determined. It was confirmed that fish products are a good source of digestible proteins, iodine, selenium, and vitamin D(3). The fundamental nutritive benefit of processed fish lies in its highly beneficial fatty acid composition, which is what imparts them healthy nutritive qualities. The high content of long-chain polyunsaturated fatty acids (LC-PUFAs), which is not noted in other food products, is particularly important. The majority of contaminants studied were present in low levels. The possible threats, particularly in the case of pregnant/nursing women and young children, can pose the levels of dioxin/furans (PCDD/Fs) and dioxin-like (dl-PCBs) in smoked Baltic salmon and smoked sprat, elevated in a relation to particular requirements concerning the content of sum of PCDD/Fs and dl-PCBs in fish (8pg WHO-TEQg(-1)). The health benefits and risks stemming from consumption of fish products were determined according to the Provisional Tolerable Weekly Intake (PTWI) for chosen contaminants (Cd, Hg, As, PCDD/Fs+dl-PCB) and the quantity of ingredients that render a fish diet healthy based on data from the EFSA Journal [EFSA (European Food Safety Authority), 2005. Opinion of the scientific panel on contaminants in the food chain on a request from the European Parliament related to the safety assessment of wild and farmed fish. EFSA J. 236, 1-118]. In regard of high content of LC-PUFAa and other nutritive ingredients, fish products available in Polish market may be considered as healthy food. However, many authors point at contaminants (methylmercury, PCDD/Fs) occurring in fish and fish products as on potential health problem, and emphasize that the amount of that hazardous substances should be limited in human diet.

Levels of PCDD/F in adipose tissue on non-occupationally exposed subjects living near a hazardous waste incinerator in Catalonia, Spain

The potential adverse effects on human health of hazardous waste incinerators (HWIs) are a subject of concern. The construction of the first and till now only HWI in Spain finished in 1999. In 2007, after approximately 9 years of regular operations in the facility, the concentrations of polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/F) were determined by HRGC/HRMS in samples of adipose tissue of 15 autopsied subjects living in the area under potential impact of the HWI (Constantí, Tarragona County, Catalonia). These data were compared with the levels found in two previous surveys performed in 1998 (baseline) and 2002. The current mean PCDD/F concentration in adipose tissue was 14.6 pg WHO-TEQ/g of fat (range: 3.3-55.4 pg WHO-TEQ/g of fat). It means significant changes (a reduction of 64% and an increase of 47%) in the mean PCDD/F levels in comparison to those found in 1998 and 2002: 40.1 and 9.9 pg WHO-TEQ/g of fat, respectively. Women showed higher levels of PCDD/F than men (23.8 vs 11.2 pg WHO-TEQ/g of fat). The increase in the last 5 years would not be directly attributable to exposure to PCDD/F emitted by the HWI, as other biological monitors such as human plasma and milk decreased during the same period.

Mortality and cancer incidence in cohorts of Swedish fishermen and fishermen's wives: updated findings

OBJECTIVES

Intake of fish is an important source for many essential substances, such as n-3 PUFA. However, certain fish also contains relatively high levels of PCBs and dioxins. In Sweden, the concentrations of these compounds are higher in fatty fish caught at the east coast as compared to fish from the west coast. The aim of the present study was to assess cancer incidence and mortality pattern among cohorts with a relatively high intake of locally caught fish from the Swedish coasts.

METHODS

Cohorts of fishermen and fishermen's wives from the Swedish west and east coasts were established. Cancer incidence and mortality patterns were assessed up to year 2002, and cause-specific standardised incidence (SIRs) and mortality (SMRs) ratios were calculated.

RESULTS

Low rates for overall mortality were observed in the two cohorts from the west coast. We observed lower than expected rates especially for respiratory and cardiovascular diseases. Incidence of colon cancer was lower than expected among the east coast fishermen and higher than expected among the east coast wives. Consistently increased incidence of lip cancer, and an elevation of the squamous cell skin cancer incidence, was seen in the fishermen cohorts.

CONCLUSIONS

The low rates for overall mortality and cancer incidence, and low death rates for major diseases, and the low colon cancer incidence, indicates a positive impact of high dietary fish consumption, and health benefits from a highly physically active work environment for the fishermen. Sun exposure as an occupational hazard among fishermen should not be neglected.

Human exposure to PCDDs, PCDFs and dioxin-like PCBs associated with seafood consumption in Korea from 2005 to 2007

Concentrations of polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs) and dioxin-like polychlorinated biphenyls (DLPCBs) were measured in 26 seafoods commonly consumed by the Korean population. The total toxic equivalent (TEQ) concentrations in seafood samples ranged from 0.01 to 6.76 pg TEQ/g wet wt, which were comparable with those found in other countries. The predominant congeners found in seafood samples were 2, 3, 4, 7, 8-PeCDF and 2, 3, 7, 8-TCDF for PCDD/Fs and PCB 118 for DLPCBs. Dietary intakes of PCDD/Fs and DLPCBs from seafood consumption were estimated for various age groups and gender in Korea. The dietary intake of PCDD/Fs and DLPCBs from seafood consumption for the general population was estimated to be 1.23 pg TEQ/kg bw/day, values that are in the range of those reported for other countries. Mackerel, tuna and hairtail contributed to the highest TEQ intakes, which collectively accounted for 66% of the total intake. Among the eight age groups investigated, 3-6 year old children had the highest TEQ exposure, followed by 50-64 years, 30-39 years and <2 years. Considering contributions of seafood consumption to the total dietary intake studies, the dietary TEQ intakes to the general population appear to be below the threshold values by international organizations. The present study may be useful for risk management for dioxins and dioxin-like contaminants in Korean seafood.

Detection, occurrence and fate of indirubin in municipal sewage treatment plants

Indirubin which has been isolated from human urine is an extremely potent AhR agonist. This paper first established an analytical method based on liquid chromatography-electrospray ionization tandem mass spectrometry (LC-ESI-MS/MS) for indirubin in complex environmental waters, and then applied this method to investigate its occurrence and fate in sewage treatment plants (STPs). For the various types of aqueous matrices considered, the absolute recoveries were from 64 to 81%, and the limits of quantification were below 0.05 ng/L Among the seven STPs studied, the average concentrations of indirubin in influents ranged from 8.3 to 29.7 ng/L, and their aqueous-phase removal rates were 72-91%. In the receiving waters, the Tonghui and Qinghe Rivers, the concentrations of indirubin (0.65-3.7 ng/L) in some samples were much higher than those in their corresponding STP effluents, suggesting that there is random discharging of untreated sewage. The fate of indirubin was investigated in mechanical and biological sewage treatment as well as in sewage-sludge treatment at a STP consisting of anoxic, anaerobic, and aerobic tanks. The indirubin was largely removed in the anoxic tank and the secondary clarifier mainly due to the biodegradation and sorption on sludge, respectively. An increase of indirubin was observed in the aerobic tank, which was due to the cleavage of indirubin conjugates.

Bioaccumulation of polybrominated diphenyl ethers (PBDEs) and polychlorinated biphenyls (PCBs) in wild aquatic species from an electronic waste (e-waste) recycling site in South China

Water and several wild aquatic species including Chinese mysterysnail, prawn, fish, and water snake were collected from a reservoir surrounded by several e-waste recycling workshops in South China. The samples were examined to investigate the levels and bioaccumulation extent of polybrominated diphenyl ethers (PBDEs) and polychlorinated biphenyls (PCBs) released from electronic waste (e-waste) which was processed by crude recycling method. Elevated levels of PBDEs [52.7 to 1702 ng/g wet weight (ww)] and PCBs (20.2-25958 ng/g ww) were found in the collected biota species compared to that in the reference samples (13.0-20.5 ng/g ww for PBDEs and 75.4-82.8 ng/g ww for PCBs). log BAF (bioaccumulation factor) ranged from 2.9 to 5.3 for PBDEs and from 1.2 to 8.4 for PCBs, depending on congeners and species. The relationship between log BAFs and log K(OW) (octanol-water partition coefficient) can be adequately described by species-specific parabolic models wherein log BAFs generally increased at log K(OW)<7 then decreased with further increasing log K(OW) both for PBDEs and PCBs. The exceptions were for Chinese mysterysnail and prawn, in which the log BAFs showed a positive linear correlation with log K(OW) for PBDEs. Some PBDE and PCB congeners showed BAF values declining from the general trend predicted by K(OW), largely attributing to metabolism of these congeners in species sampled.

Dioxins in adipose tissue of women in Southern Spain

Seventeen polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs) were quantified in adipose tissue samples of non-occupationally exposed women living in Southern Spain. Geometric mean levels of sum of congeners and WHO(PCDD/F)-TEQ(2005) were 410 and 17.9pgg(-1) fat, respectively. Among PCDDs, octachlorodibenzo-p-dioxin (OCDD) showed the highest concentration with a mean value of 265pgg(-1) fat, followed by 1,2,3,6,7,8-HxCDD (49.3pgg(-1) fat) and 1,2,3,4,6,7,8-HpCDD (45.2pgg(-1) fat). These three congeners were responsible for around 90% of the sum of all PCDD/F congeners in adipose tissue. The geometric mean 2,3,7,8-TCDD value was 1.87pgg(-1) fat. 2,3,4,7,8-PeCDF (8.43pgg(-1) fat) showed the highest concentration among the PCDFs, followed by 1,2,3,4,7,8-HxCDF (4.17pgg(-1) fat) and 1,2,3,6,7,8-HxCDF (3.28pgg(-1) fat), and these three congeners were responsible for 4% of the sum of all studied PCDD/F congeners in adipose tissue and 76% of the sum of ten PCDFs. 1,2,3,7,8,9-HxCDF was the only congener not quantified in any sample, while 1,2,3,4,7,8,9-HpCDF, 1,2,3,7,8-PeCDF, OCDF and 2,3,7,8-TCDF were found in 5, 16, 16 and 19 samples, respectively. All other congeners were quantifiable in all 20 samples. Congeners contributing most to the WHO(PCDD/F)-TEQ(2005) were 1,2,3,7,8-PeCDD (31.6%), 1,2,3,6,7,8-HxCDD (28.3%) and 2,3,4,7,8-PeCDF (14.6%). The body burden of log-transformed WHO(PCDD/F)-TEQ(2005) levels increased with age (B=0.02; 95% CI=0.01, 0.03; p=0.02). Although these adipose tissue PCDD/F levels are similar to previously published findings in Spain and other European countries, further research is needed to determine trends in the exposure of women to these chemical residues.

Concentrations of PCDD/PCDFs in plasma of subjects living in the vicinity of a hazardous waste incinerator: follow-up and modeling validation

In 2007, the concentrations of polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/PCDFs) were determined in plasma of non-occupationally exposed subjects living near the only hazardous waste incinerator (HWI) in Spain (Constantí, Tarragona County, Catalonia). These data were compared with the levels found in two previous surveys performed in 1998 (baseline) and 2002. The current mean PCDD/PCDF concentration in plasma was 9.36pg I-TEQg(-1) of lipid (range: 1.76-23.44pg I-TEQg(-1) of lipid). It means a significant reduction of the mean PCDD/PCDFs levels in plasma in comparison to the concentrations found in 1998 and 2002 (27.01 and 15.70pg I-TEQg(-1) of lipid, respectively). This important decrease agrees well with the notable reduction in the dietary intake of PCDD/PCDFs recently noted for the population of the same area (210.1pg I-TEQd(-1), 63.8pgWHO-TEQd(-1), and 27.8pgWHO-TEQd(-1), in 1998, 2002 and 2007, respectively). The current data were also used to predict theoretical PCDD/PCDF concentrations in plasma by executing a single-compartment empirically-based pharmacokinetic model on the basis of the daily intake of these pollutants by the local population.

Brominated flame retardants and polychlorinated biphenyls in fish from the river Scheldt, Belgium

Levels of polybrominated diphenyl ethers (PBDEs), hexabromocyclododecanes (HBCDs), and polychlorinated biphenyls (PCBs) were measured in several fish species originating from the river Scheldt (Belgium). Five sampling locations were chosen in a highly industrialized area along the river, while two ponds in the vicinity of the river served as reference sites. The present study is a follow-up of a survey performed in 2000 which reported extremely high levels of PBDEs and HBCDs in eel (Anguilla anguilla) collected from the same region (Oudenaarde, Flanders). The sum of tri- to hepta-BDE congeners (2270+/-2260 ng/g lipid weight (lw), range 660-11500 ng/g lw) and total HBCDs (4500+/-3000 ng/g lw, range 390-12100 ng/g lw) were one order of magnitude higher than levels usually reported from freshwater systems, indicating the presence of point sources. In most samples, levels of total HBCDs were higher than those of PBDEs, probably due to the high density of factories using HBCD as an additive brominated flame retardant (BFR). The high values of HBCDs were confirmed by both gas- and liquid-chromatography-mass spectrometry. Although BFR levels were between the highest ever reported in freshwater ecosystems, PCBs could be detected at even higher concentrations (16000+/-14300 ng/g lw, range 3900-66600 ng/g lw), being among the highest levels recorded in Belgium. The inter-sampling site variation of PBDEs, HBCDs and PCBs was comparable. All locations presented similar PBDE congener profiles, with BDE 47 being the dominant congener, followed by BDE 100, BDE 99 and BDE 49, probably originating from the former use of the penta-BDE technical mixture. In order to estimate the impact of these point sources on human exposure, we further focussed on eels which showed a considerable decrease in the PBDE and HBCD levels between 2000 and 2006. Due to the wide span in concentrations between the different sampling locations, a variable contribution to the total human exposure through local eel consumption was estimated. The calculated daily intake ranged from 3 ng to 330 ng PBDEs/day for normal eel consumers, but was as high as 9800 ng PBDEs/day for anglers, which may be considered at risk.

Detection and quantitative analysis of polychlorinated biphenyls in tilapia from Hawaiian waters

The purpose of this study was to investigate polychlorinated biphenyls (PCBs) contamination in tilapia (Oreochromis mossambicus) collected from the Manoa stream and Ala Wai Canal of O'ahu, an island of the geographically isolated Hawaiian archipelago. Our results show that the average concentrations of PCBs varied from 51.90 to 89.42 ng g(-1) lipid weight for the sampling sites. Relative toxic potencies (RTPs) and toxic equivalencies (TEQs) were determined to be 20.38-40.60 ng TCDDg(-1) lipid weight and 2.89-4.17 ng TEQ g(-1) lipid weight by 7-ethoxy-resorufin-O-deethylase (EROD) activity analysis and calculation of PCB concentrations based on toxic equivalency factors (TEFs), respectively. Penta-chlorinated congeners were found to be predominant, which revealed that Aroclor 1254 was a possible major source of PCBs in our fish samples. PCB 118, an indicator PCBs, constituted more than 55% and 30% of the total PCBs and TEQs, respectively. In addition, PCB 118 was found to have a linear correlation to the total PCBs (R=0.975) and TEQs (R=0.782). Detection of concentrated PCBs in Hawaiian waters suggests a potentially adverse impact of this pollutant on human health, as well as ecological systems, and suggests the necessity of environmental monitoring and hazard assessment of PCBs within the Hawaiian Islands.

Concentrations of PCDD/PCDFs and PCBs in retail foods and an assessment of dietary intake for local population of Shenzhen in China

OBJECTIVES

Concentrations of 17 polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs) and 18 polychlorinated biphenyls (PCBs) were measured in 11 varieties of food groups collected from retail market of Shenzhen, Guangdong province, China from 2004 to 2006. PCDD/Fs and PCBs dietary intake from varies food for the local population was estimated in the study.

METHODS

Concentrations of 17 polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs) and 12 dioxin-like polychlorinated biphenyls (PCBs) as well as 6 marker PCBs were measured in 11 varieties of food groups in total 110 food samples by isotope dilution HRGC/HRMS. PCDD/Fs and PCBs dietary intake for local population was estimated using total WHO-TEQ concentration and different food consumption amount of the local population.

RESULTS

The median WHO-TEQ concentrations of sum of PCDD/Fs and DL-PCBs varied from 0.0093 pg/g (parts per trillion) in vegetable to 9.89 pg/g in fish. Fish was followed by egg 2.46, chicken 1.73, beef 0.94, mutton 0.82, duck 0.39, pork 0.37, milk powder 0.25, vegetable oil 0.076, cereals 0.022 pg/g and vegetable. The monthly intake of PCDD/Fs and PCBs were 40.9 pg WHO-TEQ/kg b.w. for local population. Sum of fish, livestock, and poultry contributed 77% to the Estimated Monthly Intake (EMI) in local population.

CONCLUSION

Estimated dietary intake of PCDD/Fs and DL-PCBs for local population was below the provisional tolerable monthly intake(PTMI) set by Joint FAO/WHO Expert Committee on Food Additives (JECFA).

Exposure to hexachlorobenzene through fish and seafood consumption in Catalonia, Spain

The concentrations of hexachlorobenzene (HCB) were analyzed by HRGC/HRMS in 42 composite samples of the 14 most consumed marine species (sardine, tuna, anchovy, mackerel, swordfish, salmon, hake, red mullet, sole, cuttlefish, squid, clam, mussel, and shrimp) in Catalonia, Spain. The daily intake of HCB associated with this consumption was also estimated for four age groups of the population of Catalonia: children, adolescents, adults and seniors, which were in turn divided according to sex. The highest HCB levels were found in salmon and mackerel: 1.68 and 0.80 ng/g of wet weight, respectively, whereas the lowest HCB levels were found in cuttlefish, mussel, and shrimp (0.02, 0.03, and 0.04 ng/g of wet weight, respectively). In general terms, these results are within the range of data reported in recent years by a number of authors. The highest and lowest HCB intake (ng/day) corresponded to female adults (13.3) and girls (4.0), respectively. For most age/sex groups, salmon and sole were the species showing the highest contribution to HCB intake. When HCB intake was calculated according to the average body weight of the individuals in each group, the highest and lowest values corresponded to boys (0.32 ng/kg/day) and female adolescents (0.14 ng/kg/day). For all groups, HCB intake from fish and seafood consumption was considerably lower than the WHO tolerable daily intake (TDI), for non-cancer effects and for neoplastic effects in humans.

Omega-3 fatty acids and the benefits of fish consumption: is all that glitters gold?

In recent years, a number of studies have clearly remarked the nutritional benefits of fish consumption: proteins, vitamins, minerals, and especially omega-3 polyunsaturated fatty acids (PUFAs), which may protect against several adverse health effects, including coronary heart disease mortality and stroke. However, some concerns about potential health risks derived from the environmental contaminants found in fish have been also raised. Therefore, balancing adequately the risks and benefits of fish consumption is currently a nutritional/environmental health key issue. In this paper, the most recent available scientific information concerning this issue is reviewed. It is concluded that although it seems evident that fish must be an important part of a balanced diet, to choose the most suitable species in terms of levels of PUFAs and pollutants, the frequency of consumption, and the meal size are essential aspects to balance benefits and risks of a regular consumption.