Correlations of fish intake and plasma docosahexaenoic acid levels with each congener of PCDDs/PCDFs/dioxin-like PCBs in blood from the Japanese population

Serum levels of polychlorinated dibenzo-p-dioxins and polychlorinated dibenzofurans in a sample of Lebanese pregnant women: The role of dietary, anthropometric, and environmental factors

Polychlorinated dibenzo-p-dioxins (PCDDs) and polychlorinated dibenzofurans (PCDFs) are unintentionally produced, toxic environmental chemicals that persist for long years and bioaccumulate along the food chain, contaminating humans through diet. A particularly critical population subgroup is pregnant women given the adverse health effects on fetuses and newborns. Several anthropogenic sources of exposure to PCDD/Fs exist in Lebanon. Therefore, the aim of the present cross-sectional study is to measure the levels of PCDD/Fs in a sample of pregnant women in Lebanon and to explore potential associated factors. In this study, we measured serum concentrations of seven dioxins and ten furans, among 423 pregnant women recruited at delivery, using gas chromatography MS/MS. Among 269 participants, maternal sociodemographic information was collected including vicinity to landfills, incineration, pesticide use, industrial activity, and smoking. Anthropometric data were registered regarding pre-pregnancy body mass index (BMI), pre-pregnancy weight loss from restrictive diet, and gestational weight gain. Intake of major food groups generally related to PCDD/Fs was reported (fish, red meat, poultry, and dairy). Bivariate and multivariate analyses were performed to identify associations. PCDD/Fs were detected in 0 to 56.1% of the sample. Geometric mean concentrations were 75.5 (2.35) pg/g lipid and 2.25 (1.39) TEQ₂₀₀₅ pg/g lipid for total dioxins, and 2.66 (1.76) pg/g lipid and 0.34 (1.78) TEQ₂₀₀₅ pg/g lipid for total furans. Levels were relatively lower than levels previously observed in France, Germany, Mexico, Ghana, and Japan. Red meat consumption was the most consistently associated factor with a 2.38-2.57 fold increase in PCDD/F levels. Pre-pregnancy weight loss showed inverse associations with PCDD/F congeners. Vicinity to illegal incineration was also associated with a 2.32-2.43 fold increase in PCDD/F levels. In conclusion, results showed the importance of dietary, anthropometric, and environmental factors in the present sample's exposure to PCDD/Fs, in a region that contains anthropogenic sources of contamination.

Exposure and health risk assessment of secondary contaminants closely related to brominated flame retardants (BFRs): Polybrominated dibenzo-p-dioxins and dibenzofurans (PBDD/Fs) in human milk in shanghai

Polybrominated dibenzo-p-dioxins and dibenzofurans (PBDD/Fs), as the secondary environmental pollutants of the widely used brominated flame retardants (BFRs), possess the similar physicochemical and toxic properties as polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs). However, studies on human body exposure to them are extremely limited. In this study, forty human milk samples collected in Shanghai were measured for 13 PBDD/F congeners using gas chromatography-high resolution mass spectrometry (GC-HRMS), to investigate their exposure level and characteristics, potential source and corresponding health risks to breastfed infants. The results showed no PBDDs but three PBDF congeners including 2,3,7,8-TBDF, 1,2,3,4,6,7,8-HpBDF and OBDF (mean concentration (detection rates) are 3.2 pg/g (72.5%), 9.5 pg/g (100%) and 28 pg/g (67.5%), respectively) were detected. The average toxic equivalent quantity (TEQ, 0.42 pg/g lw) presented the highest concentration level compared to other regions reported. The contribution of PBDFs to the total TEQ of PBDD/Fs and PCDD/Fs is 6.8%. The correlation between PBDD/Fs and age or dietary habits was not observed, which normally existed in their chlorinated analogues-PCDD/Fs. Significant correlations were observed between PBDFs and highly brominated polybrominated diphenyl ethers (PBDEs) (especially for BDE 183 and BDE 209). The correlation between PCDD/Fs and PBDFs was not observed except 2,3,7,8-TBDF. The high PBDFs exposure in Shanghai may originate from the emission of PBDEs and/or non-PBDE BFRs in environment, according to the consistency of the environmental data previously reported. The average estimated dietary intakes (EDI) for breastfed infants is 2.0 pg TEQ/kg·bw/day (0.13-13 pg TEQ/kg·bw/day), within the range of the tolerable daily intake (TDI) for TCDD (1-4 pg TEQ/kg·bw/day) suggested by the World Health Organization (WHO). However, given the high toxicity of PBDD/Fs, the potential health risks of these pollutants for breastfed infants should be of concern.

Concentrations of PCDD/Fs in Human Blood: A Review of Data from the Current Decade

Polychlorinated dibenzo-p-dioxins and polychlorinated dibenzo-p-furans (PCDD/Fs) are environmental pollutants with great persistence, the capacity of bioaccumulation, and well known important toxic effects in humans and animals. Incinerators of hazardous, municipal and medical waste, chlorine bleaching of paper pulp, cement plants, and the traffic of motor vehicles are the most frequent emission sources of these compounds. The diet, followed at a great distance by inhalation, is generally the main way of human exposure to PCDD/Fs. Human biomonitoring is of great importance to prevent potential adverse effects derived from exposure to chemicals such as PCDD/Fs. In relation to this, blood is among the most used biological monitors. In the current review, we have summarized the recent information (2000–2009) published in the scientific literature (databases: Scopus and PubMed) on the concentrations of PCDD/Fs in blood samples of non-occupationally exposed populations, as well as in some groups of occupationally exposed individuals. We have revised a number of studies conducted in various African, American, Asian and European countries, and Australia. Unfortunately, the information is quite limited. No data are available for most countries over the world. Based on the results here reviewed, where available, the current health risks for the general populations do not seem to be of concern. Moreover, taking into account the important reductions observed in the levels of PCDD/Fs in foodstuffs, new decreases in the concentrations of PCDD/Fs in blood—and other biological tissues—are very probable in the immediate years.

Dioxins levels in human blood after implementation of measures against dioxin exposure in Japan

Background

Over the past few decades, the Japanese Ministry of the Environment has been biomonitoring dioxins in the general Japanese population and, in response to public concerns, has taken measures to reduce dioxin exposure. The objectives of this study were to assess the current dioxin dietary intake and corresponding body burden in the Japanese and compare Japanese dioxin data from 2011 to 2016 and 2002–2010 surveys. We also examined the relationship between blood dioxins and health parameters/clinical biomarkers.

Methods

From 2011 to 2016, cross-sectional dioxin surveys were conducted on 490 Japanese (242 males and 248 females, aged 49.9 ± 7.6 years) from 15 Japanese prefectures. Blood (n = 490) and food samples (n = 90) were measured for 29 dioxin congeners including polychlorinated dibenzo-para-dioxins (PCDDs), polychlorinated dibenzofurans (PCDFs), and coplanar polychlorinated biphenyls (Co-PCBs) using gas chromatography coupled with high-resolution mass spectrometry. Using the 2006 World Health Organization toxic equivalence factors, the toxic equivalents (TEQs) were calculated. Clinical biomarkers and anthropometric parameters were also measured and information on lifestyle behaviours collected. Data imputations were applied to account for blood dioxins below the detection limit.

Results

The median (95% confidence interval or CI) blood levels and dioxin dietary intake was respectively 9.4 (8.8–9.9) pg TEQ/g lipid and 0.3 (0.2–0.4) pg TEQ/kg body weight/day. The median blood dioxin level in the 2011–2016 survey was found to have decreased by 41.3% compared to the 2002–2010 surveys. Participants who were older were found to be more likely to have higher dioxin levels. Blood dioxins were also significantly associated with body mass index, triglycerides, docosahexaenoic acid, eicosapentaenoic acid, and dihomo-gamma-linoleic acid levels in blood. Furthermore, associations between blood dioxin and dietary dioxin intake were evident in the unadjusted models. However, after adjusting for confounders, blood dioxins were not found to be associated with dietary dioxin intake.

Conclusions

Blood dioxin levels declined over the past decade. This study showed that the measures and actions undertaken in Japan have possibly contributed to these reductions in the body burden of dioxins in the Japanese population.

Electronic supplementary material

The online version of this article (10.1186/s12199-018-0755-7) contains supplementary material, which is available to authorized users.

Dietary intake of fish and ω-3 polyunsaturated fatty acids and physician-diagnosed allergy in Japanese population: The Japan Environment and Children's Study

OBJECTIVE

Emerging evidence from epidemiologic studies and clinical trials indicates that ω-3 polyunsaturated fatty acids (PUFAs) may have a preventive or therapeutic effect on allergy, although the results remain controversial. The aim of this study was to investigate the association between intake of fish and ω-3 PUFAs with risk for lifetime prevalence of physician-diagnosed allergy in a Japanese population.

METHODS

Study participants were 78 621 pregnant women and 42 831 male partners from The Japan Environment and Children's Study. History of physician-diagnosed allergy (asthma, allergic rhinitis/pollinosis, allergic conjunctivitis, or atopic dermatitis) was determined by self-administered questionnaire survey. Dietary intake of fish and ω-3 PUFAs was estimated using a food frequency questionnaire.

RESULTS

Contrary to our hypothesis, an increased risk for allergy was found by multivariable logistic regression in females, especially in allergic rhinitis/pollinosis, allergic conjunctivitis, or atopic dermatitis for fish intake and in allergic rhinitis/pollinosis or allergic conjunctivitis for ω-3 PUFAs. As for male partners, risk for allergic rhinitis/pollinosis or atopic dermatitis was increased for both fish and ω-3 PUFA intake. No statistically significant results were observed for the risk for asthma in either women or men.

CONCLUSION

Fish and ω-3 PUFA intake were associated with increased risk for some allergic diseases. Further research is warranted to confirm these findings in individuals with high fish consumption.

Dioxins/furans and PCBs in Canadian human milk: 2008-2011

Human milk was collected between 2008 and 2011 as part of the Maternal - Infant Research on Environmental Chemicals (MIREC) study that was initiated to establish Canadian national estimates of maternal and infant exposure to a broad suite of environmental contaminants (e.g., persistent organic pollutants [POPs], trace elements, phthalates, etc.). Among the 1017 human milk samples collected, 298 were analysed for polychlorinated dibenzo-p-dioxins (PCDDs), dibenzofurans (PCDFs) and polychlorinated biphenyls (PCBs). World Health Organization (WHO) toxic equivalency concentrations (WHO TEQ₂₀₀₅) for PCDD/F+dioxin-like (DL) PCB ranged from 2.2pg TEQ₂₀₀₅ g^-1 lipid to 27pg TEQ₂₀₀₅ g^-1 lipid. The relative contribution of PCDDs to the overall WHO TEQ₂₀₀₅ (PCDD/F+DL PCB) has decreased from earlier investigations into POP levels in Canadian human milk. Significantly higher PCB concentrations were observed in milk from women born in Europe relative to those born in Canada (p<0.001), in contrast to results for the PCDD/Fs (p=0.496). Age was found to significantly impact milk ∑PCB concentrations (p=0.018), with elevated concentrations observed in milk from women >30years relative to those <30years of age. While this trend was also observed for the PCDD/Fs, this relationship was impacted by parity. WHO TEQ₂₀₀₅ concentrations were significantly higher in milk from primiparous women (p=0.019) and those >30years relative to those <30years of age (p<0.001). No significant differences were associated with education level or pre-pregnancy body mass index. PCB and PCDD/F concentrations have continued to decline in Canadian human milk since the last sampling of human milk was performed.

Global survey of the omega-3 fatty acids, docosahexaenoic acid and eicosapentaenoic acid in the blood stream of healthy adults

Studies reporting blood levels of the omega-3 polyunsaturated fatty acids, eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA), were systematically identified in order to create a global map identifying countries and regions with different blood levels. Included studies were those of healthy adults, published in 1980 or later. A total of 298 studies met all inclusion criteria. Studies reported fatty acids in various blood fractions including plasma total lipids (33%), plasma phospholipid (32%), erythrocytes (32%) and whole blood (3.0%). Fatty acid data from each blood fraction were converted to relative weight percentages (wt.%) and then assigned to one of four discrete ranges (high, moderate, low, very low) corresponding to wt.% EPA+DHA in erythrocyte equivalents. Regions with high EPA+DHA blood levels (>8%) included the Sea of Japan, Scandinavia, and areas with indigenous populations or populations not fully adapted to Westernized food habits. Very low blood levels (≤4%) were observed in North America, Central and South America, Europe, the Middle East, Southeast Asia, and Africa. The present review reveals considerable variability in blood levels of EPA+DHA and the very low to low range of blood EPA+DHA for most of the world may increase global risk for chronic disease.

Body burden monitoring of dioxins and other organic substances in workers at a hazardous waste incinerator

The construction in Constantí (Tarragona County, Catalonia) of the first, and up till now the only hazardous waste incinerator (HWI) in Spain, finished in 1999. In this study, we measured the concentrations of a number of organic substances determined in blood and urine of the HWI workers. Samples of 18 men and 9 women, classified according to their respective workplaces, were collected in 2011, after approximately 12 years of regular operations in the facility. The current results were compared with those of the baseline survey, as well as with the most recent surveys performed in 2008, 2009 and 2010. Plasma analyses were carried out for hexachlorobenzene (HCB), polychlorinated biphenyls (PCBs 28, 52, 101, 138, 153, and 180) and polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs), while the levels of 2,4- and 2,5-dichlorophenol (DCP), 2,4,5- and 2,4,6-trichlorophenol (TCP), pentachlorophenol (PCP) and 1-hydroxypyrene (1-HP) were measured in urine samples. In plasma, the mean concentrations were the following: 10.8μg/kg lipid for HCB; 0.8μg/kg lipid for PCB28; 0.3μg/kg lipid for PCB52; 0.5μg/kg lipid for PCB101; 42.2μg/kg lipid for PCB138; 18.5μg/kg lipid for PCB153, and 51.2μg/kg lipid for PCB180. For PCDD/Fs, the mean concentration was 4.6ng I-TEQ/kg lipid (4.7ng WHO-TEQ/kg lipid). These levels, as well as those found in urine samples, are in agreement with the data of previous surveys performed in the same area. The current results in HWI workers do not show any evident sign of occupational exposure to PCDD/Fs and other organic substances. However, these results must be considered only as an indication of potential exposure, as the study presents notable limitations, such as the reduced number of participants and the lack of data relative to the air concentrations of chemicals. Consequently, general conclusions cannot be derived and the results should not be used as a basis for the implementation of industrial hygiene measures in other HWIs.

Data-driven strategy for the discovery of potential urinary biomarkers of habitual dietary exposure

BACKGROUND

An understanding of causal relations between diet and health is hindered by the lack of robust biological markers of food exposure.

OBJECTIVE

We aimed to develop a data-driven procedure to discover urine biomarkers indicative of habitual exposure to different foods.

DESIGN

The habitual diet of 68 participants was assessed by using 4 food-frequency questionnaires over 3 mo, and participants were assigned to different consumption-frequency classes for 58 dietary components. Flow infusion electrospray-ionization mass spectrometry followed by supervised multivariate data analysis was used to determine whether the chemical composition of urine was related to specific differences in the consumption levels of each food.

RESULTS

Foods were eaten habitually in 1 of 5 basic patterns differing in range and distribution of consumption frequency. Overnight, 24-h, and fasting urine samples proved useful for biomarker lead discovery with habitual citrus exposure used as a paradigm. Exposure level discrimination robustness improved linearly as urine samples from low-frequency citrus consumers were compared with urine samples from participants reporting increasingly higher intakes. For all foods, distinctiveness and consumption-frequency range influenced the likelihood that differential dietary exposure could be detected. Model output statistics indicated foods for which biomarker lead discovery was feasible. Metabolites proposed previously as acute intake biomarkers of citrus (proline betaine), oily fish (methylhistidine), coffee (dihydrocaffeic acid derivatives), and tomato (phenolic metabolites) were also biomarkers of habitual exposure. A significance threshold in modeling output statistics was determined to guide the discovery of potential biomarkers for other foods.

CONCLUSION

This data-driven strategy can identify urinary metabolites associated with habitual exposure to specific foods. This trial has the UK registration number 4349 and was registered at isrtcn.org as CCT-NAPN-A13175.