Dietary intake of polybrominated diphenyl ethers (PBDEs) and polychlorinated biphenyls (PCBs) from fish and meat by residents of Nanjing,China

Concentrations of 14 polybrominated diphenyl ether (PBDEs) and 28 polychlorinated biphenyl (PCBs) congers were measured in 137 samples of fish and meat from Nanjing, a city in the Yangtze River Delta, China. Total concentrations of PBDEs were less in fish (mean of 180 pg/g ww; range 8.0–1100 pg/g ww), but more in non fish foods (mean of 180 pg/g ww; range 15–950 pg/g ww) than those reported from other countries. The total dietary intake of PBDEs and PCBs by humans were 9.9 ng PBDE/d and 870 ng PCB/d, respectively. The daily intake by a 60 kg adult of 2,3,7,8-tetrachlorodibenzo-p-dioxin equivalents (TEQ_WHO) from PCBs was estimated to be 49 pg ^PCBTEQ_WHO/d (0.82 pg ^PCBTEQ_WHO/kg bw), which is less than the tolerable daily intake suggested by the World Health Organization (WHO). The daily intake of meat and fish accounted for 57.2% and 42.8% of the total intake of ^PCBTEQ_WHO.     

Levels and profiles of PCDD/Fs,PCBs in mothers' milk in Shenzhen of China: Estimation of breast-fed infants’ intakes

Sixty breast milk samples were collected in Shenzhen, China from July to November in 2007. The samples were analyzed of the concentrations of polychlorinated dibenzo-p-dioxins (PCDDs), polychlorinated dibenzofurans (PCDFs) and polychlorinated biphenyls (PCBs). The range of upper-bound for ∑ TEQ-(PCDD/Fs + PCBs) in the samples was 4.10–35.3 pg TEQ g^− 1 lipid (median: 10.6 pg TEQ g^− 1 lipid; mean: 11.9 pg TEQ g^− 1 lipid). The levels of the measured contaminants in the breast milk had significant correlations with the length of inhabitation period in Shenzhen (r = 0.487, p < 0.05 for PCDD/Fs, r = 0.431, p < 0.05 for PCBs and r = 0.478, p < 0.05 for ∑ TEQ-(PCDD/Fs + PCBs)), and the consumption rate of fish (r = 0.366, p < 0.05 for PCDD/Fs, r = 0.486, p < 0.05 for PCBs and r = 0.416, p < 0.05 for ∑ TEQ-(PCDD/Fs + PCBs)), respectively. Moreover, significant positive correlations were also detected between the participant's age (r = 0.305, p < 0.05 for ∑ TEQ-PCBs and r = 0.275, p < 0.05 for ∑ TEQ-(PCDD/Fs + PCBs)) and the body burdens of these contaminants respectively. It is estimated that the daily intake (EDI) of the sum of PCDD/Fs and DL-PCBs by the breast-fed infants was 5.60–161 pg TEQ kg^− 1 bw per day (mean: 48.2 pg TEQ kg^− 1 bw per day; median: 42.2 pg TEQ kg^− 1 bw per day). The result showed that both the body burdens of PCDD/Fs and PCBs of the recruit population and the calculated EDI of the breast-fed infants were higher than those in the non-exposed areas in mainland China. This suggests that continuous surveillance on PCDD/Fs and PCBs levels in human milk is critical to more precisely evaluate the human health risk posed by the negative environmental impact in Shenzhen in the future.     

Dietary intake of polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs) by a population living in the vicinity of a hazardous waste incinerator. Assessment of the temporal trend

The concentrations of polychlorinated dibenzo-p-dioxins and polychlorinated dibenzofurans (PCDD/Fs) were determined in a number of foodstuffs purchased in various locations near a hazardous waste incinerator (HWI) in Tarragona County (Catalonia, Spain). The dietary intake of PCDD/Fs by the population of the area under potential influence of the HWI was subsequently estimated. The results were compared with previous surveys performed in the same area in 1998 (baseline), 2002 and 2006. In the present study, the highest WHO-TEQ corresponded to industrial bakery (0.183 ng/kg wet weight, ww), followed by fish (0.156 ng/kg ww), oils and fats (0.112 ng/kg fat weight), and seafood (0.065 ng/kg ww). In contrast, the lowest values were observed in pulses and tubers (0.003 ng/kg ww), and cereals and fruits (0.004 ng/kg ww). The dietary intake of PCDD/Fs by the general population was 33.1 pg WHO-TEQ/day, having fish and seafood (11.6 pg WHO-TEQ), oils and fats (4.61 pg WHO-TEQ), dairy products (3.79 pg WHO-TEQ), and industrial bakery (3.49 pg WHO-TEQ) as the groups showing the highest contribution to the total TEQ. The lowest daily contributions corresponded to pulses (0.08 pg WHO-TEQ) and tubers (0.25 pg WHO-TEQ). This intake was considerably lower than that found in the baseline study, 210.1 pg I-TEQ/day, and also notably lower than that found in the 2002 survey (59.6 pg I-TEQ/day), but slightly higher than the intake estimated in the 2006 survey, 27.8 pg WHO-TEQ/day. The results of this study show that any increase potentially found in the biological monitoring of the general population living in the area under evaluation should not be attributed to dietary exposure to PCDD/Fs.     

Levels of polychlorinated dibenzo-p-dioxins,dibenzofurans (PCDD/Fs) and biphenyls (PCBs) in blood of informal e-waste recycling workers from Agbogbloshie,Ghana, and controls

The formation and environmental release of highly toxic organohalogen compounds associated with informal recycling of waste electric and electronic equipment (e-waste) is a growing problem at e-waste dumps/recycling sites (EWRSs) in many developing countries worldwide. We chose a cross-sectional study design to measure the internal exposure to polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs) as well as polychlorinated biphenyls (PCBs) of individuals working on one of the largest EWRSs of Africa, located at Agbogbloshie, Accra, Ghana, and in controls from a suburb of Accra without direct exposure to EWRS activities. In whole blood samples of 21 age matched male exposed individuals (mean age: 24.7 years, SD 6.0) and 21 male controls (mean age: 24.4 years, SD 5.7) 17 PCDD/F congeners were determined. Moreover three indicator PCB congeners (#138, #153 and #180) were measured in blood of 39 exposed (mean age: 27.5 years, SD 11.7) and 19 non-exposed (mean age: 26.8 years, SD 9.7) patients. Besides a health examination, biometric and demographic data, residential and occupational history, occupational exposures and working conditions were recorded using a standardized questionnaire. In the exposed group, median PCDD/F-concentrations were 6.18 pg/g lipid base WHO₂₀₀₅-TEq (range: 2.1–42.7) and significantly higher compared to the control group with 4.60 pg/g lipid base WHO₂₀₀₅-TEq (range: 1.6–11.6). Concentrations were different for 2,3,7,8-TetraCDD, three HexaCDD and all 10 PCDF congeners, indicating a combustion pattern. Using a multivariate regression analysis exposure to EWRS activities was the most important determinant for PCDD/F exposure. Median PCB levels for the indicator congeners #138, #153 and #180 were 0.011, 0.019 and 0.008 μg/l whole blood (ranges: 0.002–0.18, 0.003–0.16, 0.002–0.078) in the exposed group and, surprisingly, significantly higher in the controls (0.037, 0.062 and 0.022; ranges: 0.005–0.46, 0.010–0.46, 0.004–0.21). In a multivariate regression approach e-waste related activities had no positive influence on internal PCB exposure, but rather the time living in Accra. The internal PCB exposure is in particular notable for a country where PCBs have historically never been produced or used. The impact of EWRS activities on organohalogen compound exposure of individuals working at and living in the surroundings of the Agbogbloshie EWRS, and the surprisingly high PCB exposure of people living in Accra not involved in e-waste activities require further investigation.     

The bioaccessibility of polychlorinated biphenyls (PCBs) and polychlorinated dibenzo-p-dioxins/furans (PCDD/Fs) in cooked plant and animal origin foods

In this study, we compared the effect of boiling and frying food preparation methods in determining the bioaccessibility of polychlorinated biphenyls (PCBs) and polychlorinated dibenzo-p-dioxins/furans (PCDD/Fs) in rice, cabbage, milk powder, eggs, beef, and fresh water fish. We then used these data to calculate a toxic equivalent (TEQ) for risk assessment and compared it to published values that did not account for bioaccessibility.When the foods were prepared by boiling, the mean bioaccessibility (%) in rice (PCBs: 16.5 ± 1.0, PCDD/Fs: 4.9 ± 0.3) and cabbage (PCBs: 4.2 ± 0.9, PCDD/Fs: 1.9 ± 0.7) were lower than in animal origin foods (beef, PCBs: 49.0 ± 3.3, PCDD/Fs: 7.8 ± 0.9; egg, PCBs: 29.7 ± 3.1, PCDD/Fs: 8.6 ± 1.3; fish, PCBs: 26.9 ± 2.5, PCDD/Fs: 7.9 ± 1.3; milk powder, PCBs: 72.3 ± 1.6, PCDD/Fs: 28.4 ± 1.2).When fried in cooking oil, the bioaccessibilities of all analytes in all foods increased, but the increase in plant based foods (rice, PCBs: 3.4 ×, PCDD/Fs: 3.6 ×; cabbage, PCBs: 10.3 ×, PCDD/Fs: 7.9 ×) was greater than that of animal origin foods (beef, PCBs: 1.6 ×, PCDD/Fs: 3.4 ×; egg, PCBs: 2.1 ×, PCDD/Fs: 1.8 ×; fish, PCBs: 2.8, PCDD/Fs: 3.2 ×).Comparison of PCBs/PCDD/Fs bioaccessibility in rice and cabbage showed that bioaccessibility was greater in the low fat, high carbohydrate/protein content food (rice) than in the low carbohydrate/protein, low fat content food (cabbage), regardless of the method used to prepare the food.Adjusting for bioaccessibility reduced the gross estimated daily intake (EDI) of 112 pg WHO-TEQ/day, by 88% and 63% respectively for foods prepared by boiling and frying.Our results indicate that: 1) The method used for cooking is an important determinant of PCBs/PCDD/Fs bioaccessibility, especially for plant origin foods, 2) there might be a joint fat, carbohydrate and protein effect that influences the bioaccessibilities of PCBs/PCDD/Fs in foods, and 3) use of bioaccessibility estimates would reduce the uncertainty in TEQ calculations.     

Distribution of persistent organic pollutants in serum,omental, and parietal adipose tissue of French women with deep infiltrating endometriosis and circulating versus stored ratio as new marker of exposure

Several studies have assessed the potential role of environmental chemicals in the onset, growth, and/or physiopathology of endometriosis. However, their contour in terms of considered exposure markers remains limited. The present study aimed to characterize the internal exposure levels of 78 persistent organic pollutants (POPs, including dioxins, polychlorobiphenyls, brominated flame retardants and organochlorine pesticides) in a set of 113 adult French women (45 controls, 68 cases), and to characterize the distribution of these POPs within three biological compartments (omental adipose tissue, parietal adipose tissue, and serum). For all targeted substances, the correlation between the concentrations measured in omental versus parietal adipose tissue was found strongly significant (p < 0.0001). An equivalence of the measures performed in parietal and omental adipose tissue was moreover observed with median levels of 6.4 vs. 7.4 pg/g l.w. for WHO-TEQ₂₀₀₅ PCDD/F, 4.5 vs. 4.7 pg/g l.w. for WHO-TEQ₂₀₀₅ dl-PCB, 137.1 vs. 147.9 ng/g l.w. for sum of 6 ndl-PCB, and 2.1 vs. 2.0 ng/g l.w. for sum of 7 i-PBDE, respectively. The same observation was made for individual targeted OCs compounds. Significant correlations were also observed between these concentrations determined in adipose tissue and those measured in serum for dioxins (WHO-TEQ₂₀₀₅ PCDD/F = 6.1 pg/g l.w), PCBs (WHO-TEQ₂₀₀₅ dl-PCB = 3.6 pg/g l.w., sum of 6 ndl-PCB = 81.1 ng/g l.w.), and brominated flame-retardants (sum of 7 i-PBDE = 0.9 ng/g l.w.). The circulating versus stored ratio of some exposure markers (Sum PCDDs, 1,2,3,6,7,8-HxCDF, slightly versus highly chlorinated PCBs ratio, PBDE 99 and PBB 153) was found statistically different for control and case individuals. These extended exposure data from deep infiltrating endometriosis patients are the first ones available for France and give a new insight about the equilibrium of chemicals between storage and circulating compartments that should be further considered as new marker of exposure in the context of exposure-health relationship studies.     

Polychlorinated dibenzo-p-dioxins/furans (PCDD/Fs), polychlorinated biphenyls (PCBs), and polybrominated diphenyl ethers (PBDEs) in breast milk from Zhejiang,China

Breast milk samples (n = 74) from the general maternal population of Zhejiang province were analyzed for polychlorinated dibenzo-p-dioxins/furans (PCDD/Fs), polychlorinated biphenyls (PCBs), and polybrominated diphenyl ethers (PBDEs). Samples were divided into urban and rural groups. Mean ∑PCDD/F, ∑PCB and ∑PBDE concentrations were 71.4 ± 40.8, 42774 ± 27841 and 2679 ± 944 pg g^− 1 lipid in the urban group and 38.6 ± 38.1, 26546 ± 11375 and 2731 ± 1093 pg g^− 1 lipid in the rural group, respectively. WHO-TEQ concentrations for dioxin-like PCBs and PCDD/Fs were 2.66 ± 1.43 and 3.90 ± 2.60 pg g^− 1 lipid in the urban group and 1.83 ± 0.93 and 2.27 ± 1.55 pg g^− 1 lipid in the rural group, respectively. Congener profiles for these pollutants were compared between human samples (adipose tissue and breast milk) and foodstuffs (seafood, hen eggs, and freshwater fish). Similar PCB and PCDD/F congener patterns were observed, suggesting that dietary intake is a significant source for human exposure to PCBs and PCDD/Fs. However, much lower PBDE congener levels were detected in breast milk than in foodstuffs, which implies that pathways other than dietary intake may also account for human exposure to PBDEs.     

Toxicokinetics of dioxins and other organochlorine compounds in Japanese people: Association with hepatic CYP1A2 expression levels

Concentrations of persistent organochlorine compounds (OCs) including polychlorinated dibenzo-p-dioxins (PCDDs), polychlorinated dibenzofurans (PCDFs), and polychlorinated biphenyls (PCBs) in the liver and adipose tissue of Japanese cadavers were measured, and their toxicokinetics were examined in association with hepatic cytochrome P450 (CYP) 1A protein expression levels. Total 2,3,7,8-tetrachlorodibenzo-p-dioxin toxic equivalents (TEQs) were 66 ± 74 and 65 ± 57 pg/g lipid weight (mean ± S.D.) in the liver and adipose tissue, respectively. Total PCBs (sum of 62 congeners targeted), p,p′-dichlorodiphenyl-dichloroethylene (p,p′-DDE) and β-hexachlorocyclohexane (β-HCH) were detected at concentrations over 1 μg/g lipid in both tissues of some specimens. For most of the dioxin-like congeners, total PCBs, p,p′-DDE, oxychlordane, α- and β-HCH, hexachlorobenzene (HCB), and tris(4-chlorophenyl)methane (TCPMe), age-dependent increases in concentrations were found in the adipose tissue of males. No such age-dependent trend was observed in the liver, suggesting that there are different mechanisms underlying the hepatic concentrations of OCs. Immunoblot analyses indicated detectable expression of hepatic CYP1A2 protein, whereas no CYP1A1 protein was detected. The CYP1A2 expression levels were positively correlated with concentrations (on wet weight basis) of 2,3,4,7,8-P₅CDF, the dominant TEQ-contributed congeners in the liver, indicating the induction of this CYP. Hepatic CYP1A2 protein levels were strongly correlated with the liver to adipose concentration (L/A) ratios of PCDD/F congeners with more than 5 chlorine atoms. Together with higher concentrations of the congeners in the liver than in the adipose tissue, the observation on L/A ratios of highly chlorinated PCDD/Fs suggests that induced hepatic CYP1A2 protein is involved in their sequestration in this human population, as observed in model animals (rodents). Nonetheless, the magnitude of hepatic sequestration (L/A ratio) of PCDD/Fs in this human population was lower than in other mammals and birds, reported previously. This study emphasizes the fact that toxicokinetics of some OCs can be affected at least partly by CYP1A2 protein levels in humans. For the extrapolation of their toxicokinetics from model animals to humans, knowledge on the induction and sequestration potencies of CYP1A is necessary.     

Relative effect potency estimates of dioxin-like activity for dioxins,furans, and dioxin-like PCBs in adults based on cytochrome P450 1A1 and 1B1 gene expression in blood

BackgroundIn the risk assessment of PCDDs, PCDFs, and dioxin-like (DL) PCBs, regulatory authorities support the use of the toxic equivalency factor (TEF)-scheme derived from a heterogeneous data set of the relative effect potency (REPs) estimates.ObjectivesWe sought to determine REPs for dioxin-like compounds (DLCs) using expression of cytochrome P450 (CYP) 1A1 and 1B1 mRNA in human peripheral blood mononuclear cells representing two different pathways.MethodsWe used a sex and age adjusted regression-based approach comparing the strength of association between each DLC and the cytochrome P450 (CYP) 1A1 and 1B1 mRNA expression in 320 adults residing in an organochlorine-polluted area of eastern Slovakia.ResultsWe calculated REPs based on CYP1A1 expression for 4 PCDDs, 8 PCDFs, and 1 PCB congener, and based on CYP1B1 expression for 5 PCDFs and 11 PCB congeners. REPs from CYP1A1 correlated with REPs previously derived from thyroid volume (ρ = 0.85; p < 0.001) and serum FT4 (ρ = 0.77; p = 0.009). The 13 log REPs from CYP1A1 correlated with log WHO-TEFs (r = 0.63; p = 0.015) and 11 log PCB REPs with PCB consensus toxicity factors (CTFs) for compounds with WHO-TEFs (r = 0.80; p = 0.003). The complete set of derived 56 log REPs correlated with the log CTFs (r = 0.77; p = 0.001) and log WHO-TEFs (r = 0.81; p < 0.001).ConclusionsREPs calculated from thyroid and cytochrome P450 endpoints realistically reflect human exposure scenarios because they are based on human chronic and low-dose exposures. While the CYP 1A1 seems more suitable for toxicity evaluation of PCDD/Fs, the CYP 1B1 is more apt for PCDFs and PCBs and reflects different pathways.     

Concentrations of PCDD/Fs,PCBs and PBDEs in breast milk of women from Catalonia,Spain: A follow-up study

The concentrations of polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs), polychlorinated biphenyls (PCBs), and polybrominated diphenyl ethers (PBDEs) were determined in breast milk from women living in the vicinity of a new hazardous waste incinerator (HWI) in Catalonia, Spain. The results were compared with the levels obtained in two previous surveys carried out in 1998 (baseline study) and 2002. The current concentrations of PCDD/Fs in breast milk ranged from 45 to 143 pg/g fat (2.8 to 11.2 pg WHO-TEQ/g fat), while total PCBs ranged from 114 to 617 pg/g fat (2.8 to 17.6 pg WHO-TEQ/g fat). PBDE concentrations (sum 15 congeners) ranged from 0.57 ng/g fat to 5.9 ng/g fat, with a mean value of 2.5 ng/g fat. A general decrease of the concentrations for PCDD/Fs and both planar and total PCBs was observed. Regarding to PBDE concentrations in breast milk, similar levels between the 2002 and the present study were noted. The levels of PCDD/Fs and PCBs in milk of women living in urban areas were higher than those corresponding to the industrial zones (38% and 40%, respectively). However, the current PBDE levels were slightly lower (13%) in the urban than in the industrial zone. For PCDD/Fs and PCBs, the current decreases are in accordance with the reduction in the dietary intake of these pollutants found in recent studies carried out in the same area of study.     

Long-term study of environmental levels of dioxins and furans in the vicinity of a municipal solid waste incinerator

From 1975 to 2004, a municipal solid waste incinerator (MSWI) was operating in Montcada (Barcelona, Catalonia, Spain). Because of the potential health risks derived from emission of pollutants by the facility, especially polychlorinated dibenzo-p-dioxins (PCDDs) and dibenzofurans (PCDFs), a long-term monitoring program focused on measuring the environmental levels of PCDD/Fs near the facility, and to assess the health risks for the population living in the neighborhood, was established between 1996 and 2002. A total number of 111 soil and 121 herbage samples were analyzed for PCDD/Fs during this period. Human health risks for the individuals living near the MSWI (500 and 1,000 m) were also assessed before (1998) and after modernization (2000) of the facility. It included PCDD/F inhalation, dermal contact, soil and dust ingestion, and food intake. All these data are here summarized. The environmental levels of PCDD/Fs showed that the MSWI was not the main responsible of the atmospheric pollution by these compounds. In turn, human health risks for the population living in the vicinity of the facility after introduction of a modern technology were negligible in comparison with the dietary PCDD/F exposure.     

Exposure to emissions from municipal solid waste incinerators and miscarriages: A multisite study of the MONITER Project

BackgroundMiscarriages are an important indicator of reproductive health but only few studies have analyzed their association with exposure to emissions from municipal solid waste incinerators.This study analyzed the occurrence of miscarriages in women aged 15–49 years residing near seven incinerators of the Emilia-Romagna Region (Northern Italy) in the period 2002–2006.MethodsWe considered all pregnancies occurring in women residing during the first trimester of pregnancy within a 4 km radius of each incinerator. Addresses were geocoded and exposures were characterized by a dispersion model (ADMS Urban model) producing pollution maps for incinerators based on PM₁₀ stack measurements and for other pollution sources based on NO_x ground measurements. Information on pregnancies and their outcomes was obtained from the Hospital Discharge Database. Simplified True Abortion Risks (STAR) × 100 estimated pregnancies were calculated. We ran logistic regressions adjusting for maternal characteristics, exposure to other sources of pollution, and sites, considering the whole population and stratifying by miscarriage history.ResultsThe study analyzed 11,875 pregnancies with 1375 miscarriages. After adjusting for confounders, an increase of PM₁₀ due to incinerator emissions was associated with an increased risk of miscarriage (test for trend, p = 0.042). The odds ratio for the highest quartile of exposed versus not exposed women was 1.29, 95% CI 0.97–1.72. The effect was present only for women without previous miscarriages (highest quartile of exposed versus not exposed women 1.44, 95% CI 1.06–1.96; test for trend, p = 0.009).ConclusionExposure to incinerator emissions is associated with an increased risk of miscarriage. This result should be interpreted with those of a previous study on reproductive health conducted in the same area that observed an association between incinerator exposure and preterm births.     

Determination of relative assay response factors for toxic chlorinated and brominated dioxins/furans using an enzyme immunoassay (EIA) and a chemically-activated luciferase gene expression cell bioassay (CALUX)

Determination of toxic activity requires knowledge of both the concentration and toxicity to evaluate the risk for adverse human health and environmental effects. A chemically-activated luciferase gene expression cell bioassay system (CALUX) and an antibody-based method enzyme immunoassay (EIA) were used to detect the dioxin-like response of several polybrominated, polychlorinated, and polybrominated/chlorinated dibenzo-p-dioxins/furans (PBDDs/Fs, PCDDs/Fs, and PBCDDs/Fs, respectively). It has been suggested that the biological activity of the brominated and mixed bromo/chloro compounds is similar to their chlorinated analogues (measured by binding to the Ah receptor). PBDD/F, PCDD/F, and PBCDD/F laboratory standards exhibited biological activity ranging over three orders of magnitude. The highest relative potency (REP) values from CALUX analysis, when compared to 2,3,7,8-TCDD, were 2,3,7,8-TBDD at 0.99 (± 0.07), 1,2,3,7,8-PeCDD at 0.69, and 2-Br-3,7,8-TriCDD at 0.72 (± 0.02). Cross-reactivities were calculated using EIA for several PBDDs/Fs and PBCDDs. The highest percent cross-reactivity was found for 2,3,7,8-TBDD at 138 (± 34%), and 2,3,7-TriBDD at 84 (± 36%).     

Analysis of human milk to assess exposure to PAHs,PCBs and organochlorine pesticides in the vicinity Mediterranean city Mersin,Turkey

Assessment of human exposure to environmental persistent organic pollutants such as organochlorine pesticides (OCPs), polychlorinated biphenyls (PCBs), polychlorinated dibenzo-p-dioxins/furans (PCDD/Fs) and polycyclic aromatic hydrocarbons (PAHs) based on the levels in human breast milk provides a reasonable tool not only to assess the contaminant burden in mothers but also to assess potential exposure of breast-fed neonates. There are limited data on levels of PCBs and OCPs in humans but no previous reports from Turkey on chemically determined levels PAHs in human milk. The aim of this study was to report the levels and accumulation profiles of OCPs, PCBs and PAHs in 47 breast milk samples obtained from a Mediterranean city, Mersin. High resolution analyses were performed by a gas chromatography coupled with mass spectrometer (GC–MS). Dichlorodiphenyldichloroethane (4.4′-DDE) was the dominant pollutant. Beta-hexachlorocyclohexane (ß-HCH), dichlorodiphenyltrichloroethane (4.4′-DDT), dieldrin, hexachlorobenzene, oxy-chlordane, cis-heptachlorepoxide were the other main OCPs detected. Mean levels of ΣPCB congeners and WHO_PCB-TEQ were 9.94 and 0.001 ng/g lipid, respectively. PCB 153 showed the highest concentration (3.37 ng/g lipid), followed by PCB 138 and 180. For the dioxin-like PCBs, PCB 118 was the dominant (0.97 ng/g lipid). Naphthalene, phenanthrene, pyrene and fluoranthene were the major PAHs among the 16 PAHs detected. The estimated daily intakes of DDTs, PCBs, HCHs and HCB were not exceeded the tolerable daily intake (TDI) proposed by the Health Canada Guideline. These results indicate that the neonates of Mersin city are exposed to persistent organic pollutants analyzed in this study. However, neonates born in Mersin province are less exposed than the ones born in other regions, considering OCP and PCB levels in breast milk.     

Measurement and health risk assessment of PM2.5, flame retardants,carbonyls and black carbon in indoor and outdoor air in kindergartens in Hong Kong

Indoor air pollution is closely related to children's health. Polybrominated diphenyl ethers (PBDEs) and dechlorane plus (DP) transmitted through indoor PM_2.5 and dust, along with carbonyl compounds and black carbon (BC) aerosol were analysed in five Hong Kong kindergartens. The results showed that 60% of the median PM_2.5 levels (1.3 × 10¹ to 2.9 × 10¹ μg/m³ for indoor; 9.5 to 8.8 × 10¹ μg/m³ for outdoor) in the five kindergartens were higher than the guidelines set by the World Health Organization (2.5 × 10¹ μg/m³). Indoor PM_2.5 mass concentrations were correlated with outdoor PM_2.5 in four of the kindergartens. The PBDEs (0.10–0.64 ng/m³ in PM_2.5; 0.30–2.0 × 10² ng/g in dust) and DP (0.05–0.10 ng/m³ in PM_2.5; 1.3–8.7 ng/g in dust) were detected in 100% of the PM_2.5 and dust samples. Fire retardant levels in the air were not correlated with the levels of dust in this study. The median BC concentrations varied by > 7-fold from 8.8 × 10² ng/m^− 3 to 6.7 × 10³ ng/m^− 3 and cooking events might have caused BC concentrations to rise both indoors and outdoors. The total concentrations of 16 carbonyls ranged from 4.7 × 10¹ μg/m³ to 9.3 × 10¹ μg/m³ indoors and from 1.9 × 10¹ μg/m³ to 4.3 × 10¹ μg/m³ outdoors, whilst formaldehyde was the most abundant air carbonyl. Indoor carbonyl concentrations were correlated with outdoor carbonyls in three kindergartens. The health risk assessment showed that hazard indexes (HIs) HIs of non-cancer risks from PBDEs and DPs were all lower than 0.08, whilst non-cancer HIs of carbonyl compounds ranged from 0.77 to 1.85 indoors and from 0.50 to 0.97 outdoors. The human intake of PBDEs and DP through inhalation of PM_2.5 accounted for 78% to 92% of the total intake. The cancer hazard quotients (HQs) of formaldehyde ranged from 4.5E − 05 to 2.1E − 04 indoors and from 1.9E − 05 to 6.2E − 05 outdoors. In general, the indoor air pollution in the five Hong Kong kindergartens might present adverse effects to children, although different schools showed distinct pollution levels, so indoor air quality might be improved through artificial measures. The data will be useful to developing a feasible management protocol for indoor environments.     

Associations between PBDEs in office air,dust, and surface wipes

Increased use of flame-retardants in office furniture may increase exposure to PBDEs in the office environment. However, partitioning of PBDEs within the office environment is not well understood. Our objectives were to examine relationships between concurrent measures of PBDEs in office air, floor dust, and surface wipes.We collected air, dust, and surface wipe samples from 31 offices in Boston, MA. Correlation and linear regression were used to evaluate associations between variables. Geometric mean (GM) concentrations of individual BDE congeners in air and congener specific octanol–air partition coefficients (K_oa) were used to predict GM concentrations in dust and surface wipes and compared to the measured concentrations.GM concentrations of PentaBDEs in office air, dust, and surface wipes were 472 pg/m³, 2411 ng/g, and 77 pg/cm², respectively. BDE209 was detected in 100% of dust samples (GM = 4202 ng/g), 93% of surface wipes (GM = 125 pg/cm²), and 39% of air samples. PentaBDEs in dust and air were moderately correlated with each other (r = 0.60, p = 0.0003), as well as with PentaBDEs in surface wipes (r = 0.51, p = 0.003 for both dust and air). BDE209 in dust was correlated with BDE209 in surface wipes (r = 0.69, p = 0.007). Building (three categories) and PentaBDEs in dust were independent predictors of PentaBDEs in both air and surface wipes, together explaining 50% (p = 0.0009) and 48% (p = 0.001) of the variation respectively. Predicted and measured concentrations of individual BDE congeners were highly correlated in dust (r = 0.98, p < 0.0001) and surface wipes (r = 0.94, p = 002). BDE209 provided an interesting test of this equilibrium partitioning model as it is a low volatility compound.Associations between PentaBDEs in multiple sampling media suggest that collecting dust or surface wipes may be a convenient method of characterizing exposure in the indoor environment. The volatility of individual congeners, as well as physical characteristics of the indoor environment, influence relationships between PBDEs in air, dust, and surface wipes.     

The ‘take home’ burden of workplace sensitizers: Flour contamination in bakers' families

BackgroundExposure to flour/flour constituents is a leading cause of occupational asthma. Paternal occupational exposure to flour has been associated with increased likelihood of childhood asthma, raising the possibility of para-occupational exposure whereby family members are exposed to sensitizers ‘taken home’ on contaminated skin/clothing.ObjectiveTo establish whether workplace contamination of skin/clothing with wheat flour allergen (WFA) and fungal α-amylase (FAA) is associated with increased levels of these allergens in bakers' homes.MethodsBakeries in north-east Scotland were invited to participate. Control subjects were recruited from University of Aberdeen staff and students. Exposure assessment was carried out in bakeries, bakers' cars and the homes of bakers and controls using surface wipe and vacuum sampling; samples were analyzed for total protein, FAA and WFA.Results164 wipe samples and 49 vacuum samples were collected from 38 bakers (from 5 bakeries) and 10 controls.Compared to non-bakers, bakers had higher median levels of WFA and FAA in house vacuum samples; the difference was statistically significant for WFA/total protein (515.8 × 10^− 6 vs. 163.7 × 10^− 6, p = 0.031), FAA/total protein ratios (1.45 × 10^− 6 vs. 0.04 × 10^− 6, p < 0.001) and FAA loading (median 1.2 pg/cm² vs. 0.1 pg/cm², p < 0.001) with workplace exposure–home contamination relationships between bakers with higher and lower workplace contamination.We found positive correlations between WFA contamination of the bakers' foreheads and cars (r_s0.57, p = 0.028), foreheads and houses (r_s0.46, p = 0.025), shoes and houses (r_s0.45, p = 0.029); and between FAA contamination of shoes and houses (r_s0.46, p = 0.023), and cars and houses (r_s0.70, p = 0.008). There was no evidence of bakers using work-sourced flour for domestic baking.ConclusionsThis work demonstrates pathways for ‘take home’ exposure of occupationally sourced flour. Taken with our previous work, showing that bakers' children are more likely to have asthma, this supports the need for further investigation to establish whether ‘take home’ of occupationally sourced flour is widespread with health consequences.     

Biomonitoring short- and long-term exposure to the herbicide terbuthylazine in agriculture workers and in the general population using urine and hair specimens

The aim of this work was to evaluate short-term and long-term exposure to terbuthylazine (TBA) in agriculture workers (AW), rural residents (RR), and urban residents (UR) using urine and hair specimens. Twelve AW, 13 RR, and 17 UR were included in the study. Urine spot samples were collected with two different protocols. AW urine samples were collected before the application season (February, U₀), at bedtime on the day of TBA application (March–May, U₁), and prior to the next shift on the day after TBA application (U₂). RR and UR urine samples were collected on any day during the application season (U_e). Hair samples were collected for all subjects before the application season (February, H₀) and at the end of the season (June, H₁). TBA and its metabolite desethylterbuthylazine (DET) were measured by liquid chromatography coupled with triple quadrupole mass spectrometry detection. DET was exclusively found in urine, while TBA was mostly found in the hair. In the AW, the urinary levels of DET were not detected in the U₀ samples, and they increased to median levels of 1.81 and 2.94 μg/L in the U₁ and U₂ samples, respectively (p < 0.001). In the RR and UR, DET was not detected in the U_e samples. In the UR, TBA was not detected in the H₀ samples, and the median levels of TBA were 0.01 ng/mg hair in both the AW and RR. In the H₁ samples, the median TBA levels were not detected, 0.01, and 0.08 ng/mg hair in the UR, RR, and AW, respectively (p < 0.001). Urinary DET and hair TBA are promising candidates for biomonitoring short- and long-term exposure to TBA. The use of this herbicide in agriculture leads to exposure in rural residents.     

Priority and emerging flame retardants in rivers: Occurrence in water and sediment,Daphnia magna toxicity and risk assessment

The occurrence, partitioning and risk of eight polybrominated diphenyl ethers (PBDEs), nine new brominated (NBFRs) and ten organophosphorus flame retardants (OPFRs) were evaluated in three Spanish rivers suffering different anthropogenic pressures (Nalón, Arga and Besòs). OPFRs were ubiquitous contaminants in water (ΣOPFRs ranging from 0.0076 to 7.2 μg L^− 1) and sediments (ΣOPFRs ranging 3.8 to 824 μg kg^− 1). Brominated flame retardants were not detected in waters, whereas ΣPBDEs ranged from 88 to 812 μg kg^− 1 and decabromodiphenyl ethane (DBDPE) reached 435 μg kg^− 1 in sediments from the River Besòs, the most impacted river. The occurrence of flame retardants in river water and sediment was clearly associated with human activities, since the highest levels occurred near urban and industrial zones and after wastewater treatment plants discharge. Daphnia magna toxicity was carried out for OPFRs, the most ubiquitous flame retardants, considering individual compounds and mixtures. Toxicity of nine tested OPFRs differed largely among compounds, with EC₅₀ values ranging over three magnitude orders (0.31–381 mg L^− 1). Results evidenced that these compounds act by non-polar narcosis, since their toxicity was proportional to their lipophilicity (K_ow). Furthermore, their joint toxicity was additive, which means that single and joint toxicity can be predicted knowing their concentration levels in water using quantitative structure activity relationships (QSARs) and predictive mixture models. Based on these results, a risk assessment considering joint effect was performed calculating and summing risk quotients (RQs) for the water and sediment samples. No significant risk to D. magna (ΣRQs < 1) was observed for any of the monitored rivers.     

Fate,distribution, and contrasting temporal trends of perfluoroalkyl substances (PFASs) in Lake Ontario,Canada

Lake Ontario water and sediment collected from tributary, nearshore, and open lake sites were analyzed for perfluoroalkyl substances (PFASs), namely perfluoroalkyl carboxylic acids (PFCAs, F(CF₂)_nCO₂⁻; n = 6-11,13) and perfluoroalkane sulfonic acids (PFSAs, F(CF₂)_nSO₃⁻; n = 6,8,10). Survey results of surface sediment and water indicated that shorter chained PFASs were predominant in and near urban/industrial area watersheds, while longer chained PFASs were predominant in fine-grained sediment from major depositional basins. Niagara River suspended solids (1981–2006) demonstrated temporal trends that may have been influenced by recent changes in North American production and use of PFASs. Perfluorooctane sulfonate (PFOS) reached a peak concentration in 2001 of 1.1 ng/g, followed by a decrease from 2001 to 2006 (half-life = 9 years). Perfluorooctanoic acid (PFOA) increased from 2001 to 2006 (doubling time = 2 years) reaching a peak concentration of 0.80 ng/g. In contrast, three sediment cores from western, central, and eastern Lake Ontario showed increasing temporal trends to surface sediment for all PFASs. PFOA and PFOS concentrations increased from 1988 to 2004 (doubling time = ~ 4 years) in the western Lake Ontario core. The observed variations in temporal trends from different environmental compartments may be a result of the physico-chemical properties of PFASs, ongoing emissions, and the environmental transformation and degradation of PFAS precursor compounds.