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Women in the United States have breast milk concentrations of polybrominated diphenyl ethers (PBDEs) that are among the highest in die world, leading to concerns over the potential health implications to breastfeeding infants during critical stages of growth and development Developing cost-effective and sustainable methods for assessing chemical exposures in infants is a high priority to federal agencies and local communities. PBDE data are available in nationally representative serum samples but not in breast milk. As a method to predict PBDE concentrations in U.S. breast milk, we present the development of congener-specific linear regression partitioning models and their application to U.S. serum data. Models were developed from existing paired milk and serum data and applied to 2003-2004 NHANES serum data for U.S. women. Highest estimated median U.S. breast milk concentrations were for BDE-47 (30.6 ng/g lipid) and BDE-99 (6.1 ng/g lipid) with the median concentration of а7PBDEs estimated at 54.2 ng/g lipid. Predictions of breast milk PBDE concentration were consistent with reported concentrations from 11 similarly timed U.S. studies. When applied to NHANES data, these models provide a sustainable method for estimating population-level concentrations of PBDEs in U.S. breast milk and should improve exposure estimates in breastfeeding infants [ABSTRACT FROM AUTHOR]

Tetrabromobisphenol-A (TBBP-A) and hexabromocyclododecanes (HBCDs) are brominated flame retardants that have been found in human milk and serum throughout the world, but have received comparatively little attention in the United States. The objective of this study is to determine concentrations of these analytes in samples of breast milk collected from first-time mothers in the Greater Boston, Massachusetts area and to explore predictors of exposure. Human milk samples were analyzed by LC-ESI-MS/MS for TBBP-A, HBCDs (the α, β, and γ diastereomers), and HBCD degradation products: pentabromocyclododecanes (PBCDs) and tetrabromocyclododecadienes (TBCDs). HBCD diastereomers were detected in all samples with α-HBCD present in the highest proportion. TBBP-A, PBCDs, and TBCDs were detected in 35%, 42%, and 56% of the analyzed samples, respectively. Self-reported demographic, dietary and behavioral data were examined as predictors of HBCD levels. Levels of HBCD were significantly, positively associated with the number of stereo and video electronics in the home (17% increase/item; 95% Confidence Interval (CI) = 4-31%) and reduced in participants who regularly chose organic foods compared to those who did not (0.51, 95% CI = 0.32-0.82). These results suggest that lifestyle factors are related to body burdens of HBCD and that domestic electronics may be an important source of HBCD exposure in the indoor environment. [ABSTRACT FROM AUTHOR]

The United States Environmental Protection Agency has identified quantification of trichloroethylene (TCE), an industrial solvent, in breast milk as a high priority need for risk assessment. Water and milk samples were collected from 20 households by a lactation consultant in Nogales, Arizona. Separate water samples (including tap, bottled, and vending machine) were collected for all household uses: drinking, bathing, cooking, and laundry. A risk factor questionnaire was administered. Liquid-liquid extraction with diethyl ether was followed by GC-MS for TCE quantification in water. Breast milk underwent homogenization, lipid hydrolysis, and centrifugation prior to extraction. The limit of detection was 1.5 ng/mL. TCE was detected in 7 of 20 mothers' breast milk samples. The maximum concentration was 6 ng/mL. TCE concentration in breast milk was significantly correlated with the concentration in water used for bathing (? = 0.59, p = 0.008). Detection of TCE in breast milk was more likely if the infant had a body mass index <14 (RR = 5.2, p = 0.02). Based on average breast milk consumption, TCE intake for 5% of the infants may exceed the proposed U.S. EPA Reference Dose. Results of this exploratory study warrant more in depth studies to understand risk of TCE exposures from breast milk intake. [ABSTRACT FROM AUTHOR]

This paper provides the results of an investigation on dietary intakes and internal doses of polycyclic aromatic hydrocarbons (PAHs) for nonsmoking women from Beijing, China. Concentrations of PAHs were measured by gas chromatography/mass spectrometry (GC/MS) for human milk, placenta, and umbilical cord blood samples from 40 nonsmoking women and for 144 composite food samples covering major food categories. Information on food consumption and estimated ingestion doses of PAHs by the cohort was also collected individually. Relationship among the studied human samples and relative importance of breastfeeding to the total exposure dose of infants were addressed. The median (mean and standard deviation) total concentrations of 15 PAHs in human milk, placenta, and umbilical cord blood with (or without) fat normalization were 278 (9.30 ± 5.75), 819 (35.9 ± 15.4), and 1370 (5.521 ± 3.71) ng/g of fat, respectively, and the corresponding levels of benzo[a]pyrene equivalent (B[a]Pequiv) were 11.2 (0.473 ± 0.605), 16.2 (0.717 ± 0.318), and 13.1 (0.140 ± 0.225) ng/g of fat, respectively. The calculated intake of B[a]Pequiv by Beijing cohort varied from 0.609 to 4.69 ng·kg-1·day-1 with a median value of 1.93 (2.09 ± 0.921 mean ± standard deviation) ng·kg-1·day-1. Significant correlations were found among human milk, placenta, and umbilical cord blood (p < 0.05) for low-molecular-weight PAHs, indicating selective transfer potential of individual PAHs from mother to fetus. Internal dose of PAHs was not in proportion to amounts of food ingestion, daily dietary intake, lifestyle, and social-demographic characteristics of the participants (p > 0.05). Ingested doses of PAHs (3.00-102 ng·kg-1·day-1), which were much higher than the inhaled doses (0.152-8.50 ng·kg-1·day-1), were 3-4 orders of magnitude lower than the recommended reference doses, unlikely to impose any obvious risk based on current knowledge. [ABSTRACT FROM AUTHOR]

Breast milk samples collected during 2003-2005 from 82 first-time mothers in 24 communities located throughout California contained levels of polybrominated diphenyl ethers (Σtri-hexa (8)PBDEs; median = 53.3 ng/g lw, range = 9.60-1291) and polychlorinated biphenyls (Σ12PCBs; median = 73.4 ng/g lw, range = 22.2-433) that are among the highest in the world. PBDE levels varied 100-fold. BDE-47 was the dominant PBDE congener, with levels exceeding the U.S.EPA Reference Dose (RfD) for neurodevelopmental toxicity (100 ng/kg/day) in most (60%) breast milk samples. In some samples, BDE-209 (2/82) and/or BDE-153 (5/82) were the dominant congeners, suggesting that BDE-209 can transfer to breast milk and/or break down in the mother and transfer to the nursing infant as the lower-brominated PBDEs associated with adverse effects. PBDE levels in California breast milk are approaching those of PCBs, and the trend PBDEs > PCBs may continue as PBDEs migrate from products to the indoor and outdoor environments. [ABSTRACT FROM AUTHOR]

At present scientific knowledge on depuration rates of persistent organic pollutants (POPs) is limited and the previous assumptions of considerable reduction of body burdens through breast-feeding have recently been challenged. We therefore studied elimination rates of important POPs in nine Norwegian primiparous mothers and one mother breast-feeding her second child by collecting breast-milk samples (n = 70) monthly from about two weeks to up to twelve months after birth. Perfluorinated compounds (PFCs), polybrominated diphenyl ethers (PBDEs), hexabromocyclododecane (HBCD), and polychlorinated biphenyls (PCBs) were determined in the breast-milk samples. Linear mixed effect models were established for selected compounds, and significant decreases in the range of 1.2-4.7% in breast-milk concentrations per month were observed for a wide range of PCBs and PBDEs. For the first time, depuration rates for perfluorooctylsulfonate (PFOS) and perfluorooctanoic acid (PFOA) are presented, being 3.8 and 7.8% per month, respectively (p < 0.05). The relative amount of the branched PFOS isomers in the breast-milk samples was 18% on average (range 6-36%, RSD 30%). There were no significant differences in isomer pattern between the mothers, or changes during the lactation period. After a year of nursing the breast-milk concentrations of PFCs, PBDEs, and PCBs were reduced by 15-94%. [ABSTRACT FROM AUTHOR]

Dioxins and PCBs are environmental pollutants, proven to be immunotoxic. In the period 1987-1991 a cohort of mother-baby pairs was initiated to detect abnormalities in relation to dioxin levels in the mother's milk. At birth and at follow-up at 8-12 years, immunological and hematological effects were seen, prompting us to perform a new follow-up during adolescence. In addition, we assessed the immunological and hematological parameters in relation to current levels of PBDEs and PCBs. In the Netherlands, the pre- and postnatal exposure to dioxins have been studied prospectively since 1987. Venapuncture was performed to assess hematological (Hemoglobin, thrombocytes, thrombopoietin) and immunological (leukocytes, leukocyte differentiation) parameters and the current serum levels of dioxin, dioxinlike(dl)-PCBs and PBDEs. A decrease in the number of polymorphic neutrophils was found in adolescents with higher dl-PCBs in their serum (p = 0.021). No relation with total leukocytes, thrombocytes, hemoglobin, or thrombopoietin levels was seen. Similarly, we found no relation between prenatal, nor current dioxin levels and the hematological and the immunological parameters determined. The ΣPBDEs were negatively associated with the number of lymphocytes (p = 0.01) and positively associated with the hemoglobin concentration (p = 0.003). Those effects on the innate immunity by current levels of dl-PCBs and on the adaptive immunity by PBDEs are disconcerting, especially as the dl-PCB (0.04-7.8 WHOTEQ pg/g lipid, mean: 2.2 WHOTEQ pg/g lipid) and ΣPBDE levels (mean 14.0 ng/g lipid, including one outlier with a sum of 73.6 ng/g lipid) were not high. [ABSTRACT FROM AUTHOR]

Residues of hexachlorocyclohexane isomers (HCHs, including α-HCH, β-HCH, γ-HCH, and δ-HCH) in human milk of two populations from Beijing and Shenyang, China were studied. In addition to human milk samples from 76 women, 271 composite food samples covering major food categories were also collected for HCH analysis. The food consumption and social-demographic characteristics of the studied populations were investigated and dietary intakes of HCHs of the milk donors on an individual basis were calculated. The dependences of HCH concentration in the human milk on food consumption, dietary intake of HCHs, and demographic characteristics were studied. It was found that β-HCH dominated the HCHs detected in the human milk. Although there were dramatic declines in HCHs in the human milk compared to historical data, the current levels (312 ± 377 na/g fat and 360 ± 235 ng/g fat as the means and standard deviations for Beijing and Shenyang, respectively) were still much higher than those reported in other cities within China and around the world. It was revealed that the residual level of HCHs in the human milk was positively correlated (p < 0.001) to the quantities of food consumption. Milk, oil, vegetables, and fruits contributed a large portion of HCHs intake in Beijing, while cereals, milk, vegetables, oil, and meat were the most important dietary intake sources of HCHs in Shenyang. Both daily dietary intake of HCHs (p <0.001) and body mass index (BMI, body weight divided by the squared height) (p < 0.01) were significantly correlated with human milk HCHs. A nonlinear model was developed to predict the residues of HCHs in human milk using both dietary intake and BMI as independent variables. Potential risk of the HCH exposure of breastfed infants is discussed. [ABSTRACT FROM AUTHOR]

Tetrabromobisphenol A (TBBPA) and hexabromocyclododecane diastereoisomers (αβ, and γ-HBCD) were determined in 24 pooled human milk samples and 48 Chinese total diet study (TDS) samples collected in 2007. On the basis of ultra performance liquid chromatography-mass spectrometry (UPLC- MS/MS) analysis, levels of TBBPA ranged from

Manganese exposure and biomarker concentrations during early pregnancy and lactation were investigated in 408 women living in an area with elevated concentrations of both arsenic and manganese in drinking water derived from wells. About 40% of the water samples had manganese concentrations above the World Health Organization's guideline value and showed a strong inverse correlation with arsenic concentrations. Water manganese was found to correlate to urine concentrations, but not to blood or breast milk concentrations. No correlations were found among manganese concentrations in urine, blood, or breast milk. Compared to other populations, manganese concentrations in both urine and blood, but not breast milk, were elevated in the Bangladeshi women and more similar to those of occupationally exposed groups. The lack of associations with water manganese is likely due to variable exposure via water and food, and differences in bioavailability, as well as a complex and/or strict regulation of intestinal manganese absorption, in turn being influenced by nutritional as well as physiological and genetic factors. The results indicate that elevated maternal manganese exposure does not necessarily lead to exposure of breast-fed infants, stressing the importance of breast feeding in high manganese areas. However,the implications of fetal exposure from elevated maternal exposure need further investigation. [ABSTRACT FROM AUTHOR]

Samples of human breast milk (n = 33) from A Corua (NW of Spain) collected in 2006 and 2007 were analyzed for HBCD diastereoisomers and enantiomers. HBCD was detected in 30 out of 33 human milk samples, at concentration levels ranging between 3 and 188 ng/g lw, with a median value of 27 ng/g lw, showing higher levels than those published for other countries. Diastereoisomeric pattern shows the predominance of the γ-isomer, with low contribution of the α-isomer and the β-isomer being below the limit of quantification. However, in six samples, there is a dominance of the α-isomer versus the γ-isomer. For the first time, HBCD enantiomeric analysis was carried out in human breast milk samples, showing a selective enantiomeric enrichment in human body. As regards α-HBCD, an enrichment of (-)-enantiomer was observed. However, in the case of γ-HBCD, no clear preference for one or the other enantiomer was found. Finally, and based on the calculated HBCD concentrations in human breast milk from Spain, the daily ingestion rate of HBCD was estimated. The nursing infant dietary intake for HBCD was set at 175 ng (kg of body weight)-1 day-1. [ABSTRACT FROM AUTHOR]

The occurrence of perfluorinated compounds (PFCs) in human blood is known to be widespread; nevertheless, the sources of exposure to humans, including infants, are not well understood. In this study, breast milk collected from seven countries in Asia was analyzed (n = 184) for nine PFCs, including perfluorooctanesulfonate (PFOS) and perfluorooctanoate (PFOA). In addition, five brands of infant formula (n = 21) and 11 brands of dairy milk (n = 12) collected from retail stores in the United States were analyzed, for comparison with PFC concentrations previously reported for breast milk from the U.S. PFOS was the predominant PFC detected in almost all Asian breast milk samples, followed by perfluorohexanesulfonate (PFHxS) and PFOA. Median concentrations of PFOS in breast milk from Asian countries varied significantly; the lowest concentration of 39.4 pg/mL was found in India, and the highest concentration of 196 pg/mL was found in Japan. The measured concentrations were similar to or less than the concentrations previously reported from Sweden, the United States, and Germany (median, 106-166 pg/mL). PFHxS was found in more than 70% of the samples analyzed from Japan, Malaysia, Philippines, and Vietnam, at mean concentrations ranging from 6.45 (Malaysia) to 15.8 (Philippines) pg/mL PFOA was found frequently only in samples from Japan; the mean concentration for that country was 77.7 pg/mL None of the PFCs were detected in the infant formula or dairy-milk samples from the U.S. except a few samples that contained concentrations close to the limit of detection. The estimated average daily intake of PFOS by infants from seven Asian countries, via breastfeeding, was 11.8 ± 10.6 ng/kg bw/day; this value is 7-12 times higher than the estimated adult dietary intakes previously reported from Germany, Canada, and Spain. The average daily intake of PFOA by Japanese infants was 9.6 ± 4.9 ng/kg bw/day, a value 3-10 times greater than the estimated adult dietary intakes reported from Germany and Canada. The highest estimated daily intakes of PFOS and PFOA by infants from seven Asian countries studied were 1-2 orders of magnitude below the tolerable daily intake values recommended by the U.K. Food Standards Agency. [ABSTRACT FROM AUTHOR]

Perchlorate, thiocyanate, and iodine excretion in urine and milk of 13 breastfeeding women was investigated and the results were interpreted by a model of parallel/competitive transport of these species by the sodium iodide symporter. For each species i, we assumed physiological homeostasis, where iT,in equals the corresponding total excretion in urine and milk (ie,u + ie,m). The fraction of the total excretion that appeared in milk fi,mwas measured and ranged from 0.394-0.781, 0.018-0.144, and 0.086-0.464 for perchlorate, thiocyanate, and iodine, respectively. The corresponding median values were 0.541, 0.053, and 0.177, respectively. The selectivity factors of perchlorate over iodide transport, and thiocyanate over iodide transport, defined as fPC,m/fl,m, and fSCN,m/fl,m, respectively, were 3.14 ± 1.20 and 0.27 ± 0.26 while PCT,in, SCNT,in, and lT,in among individuals varied 4.9, 5.0, and 8.4×, respectively. These transport selectivities are an order of magnitude lower than those indicated by in vitro studies, suggesting that the impact of both these anions on inhibiting iodide transport in milk may have been overestimated in the extant literature. On the other hand, our results showed that 12 of 13 infants did not have an adequate intake of iodine as defined by the Institute of Medicine and 9 out of 13 infants were likely ingesting perchlorate at a level exceeding the reference dose suggested by the National Academy of Science panel. [ABSTRACT FROM AUTHOR]

Buckminsterfullerene (C60) can form water suspensions (nC60) that exert toxic effects. While reactive oxygen species (ROS) generation has been implicated as the mechanism for mammalian cytotoxicity, we propose that nC60 exerts ROS-independent oxidative stress in bacteria, with evidence of protein oxidation, changes in cell membrane potential, and interruption of cellular respiration. This mechanism requires direct contact between the nanoparticle and the bacterial cell and differs from previously reported nanomaterial antibacterial mechanisms that involve ROS generation (metal oxides) or leaching of toxic elements (nanosilver). [ABSTRACT FROM AUTHOR]

This paper presents the results of an investigation on association between dietary intakes and human milk concentrations of dichlorodiphenyltrichloroethane and metabolites (DDTs) of two populations from Beijing and Shenyang, China. We analyzed human milk samples from 76 women and 287 composite food samples covering major food categories for concentrations of DDTs. We also collected information on food consumptions and calculated dietary intakes of DDTs of the participants on individual basis. The median values of the measured DDTs in human milk were 125 ng/g lipid and 132 ng/g lipid for the samples from Beijing and Shenyang, respectively. The mean (±standard deviation) daily dietary intakes of DDTs by the two groups were 32.0 ± 14.2 ng/kg·day and 27.9 ± 11.3 ng/kg·day, respectively. The temporal trends of decreasing in DDTs and increasing in DDE/DDT ratio suggested that the residuals were primarily from historical application. We found a significant correlation between human milk concentration and daily dietary intake of DDTs, while the dietary intake could explain 22% of the variation in the DDTs in human milk. In addition to dietary exposure, we also found that maternal body mass index (body weight divided by the squared height), body weight, body height, and mother's age contributed significantly to the variation of DDTs in human milk after intake normalization. The result of a probabilistic risk assessment indicated that the exposure of infants to DDTs through breast feeding would be a public health concern for years to come, although breast feeding is still recommended. [ABSTRACT FROM AUTHOR]

We analyzed two nitro musks (musk xylene and musk ketone) and five polycyclic musks (HHCB, AHTN, ADBI, ATII, and AHDI) in mother's milk from primiparae women (N = 101) living in Uppsala County, Sweden, 1996-2003. Possible temporal trends in musk concentrations and associations with lifestyle/medical factors, such as use of perfumed products during pregnancywere studied. HHCB showed the.highest median concentration (63.9 ng/g lipid) followed by AHTN (10.4 ng/g) and musk xylene (MX) (9.5 ng/g). Concentrations of the other substances were, in most cases, below the quantification limit (2.0-3.0 ng/g). Women with a high use of perfume during pregnancy had elevated milk concentrations of HHCB, and elevated concentrations of AHTN were observed among women reporting use of perfumed laundry detergent. This strongly suggests that perfumed products are important sources of musk exposure both among the mothers and the nursed infants. Concentrations of AHTN and MX declined significantly between 1996 and 2003, suggesting a decline in the industrial use of the compounds in consumer products, or alterations in the consumer use pattern of perfumed products. No temporal trend in HHCB concentrations was seen. The lack of toxicity data makes it difficult to generalize about the safety of musk exposure of breast-fed infants. [ABSTRACT FROM AUTHOR]

Persistent organic pollutants (POPs) were detected in 88 maternal adipose tissue samples collected during year 2004 to 2006, in Singapore. Organochlorine pesticides (OCPs) were the most dominant followed by polychlorinated biphenyls (PCBs) and polybrominated diphenyl ethers (PBDEs). Multivariate data analyses (MVA) including principal component analysis (PCA), partial least-squares regression (PLSR), and partial least-squares discriminant analysis (PLS-DA) were applied to elucidate the relationship between concentrations of POPs in adipose tissues and donors' characteristics. Food consumption played the most significant role in accounting for levels of POPs in adipose tissue. Fish and poultry consumption was the route of PCBs and PBDEs in mothers in Singapore, while β-HCH came mainly from vegetables. An age-dependent accumulation of POPs was found for β-HCH and PCB congeners, and lactation and gestation functioned as a decontamination processes for PCBs in adipose tissue. Gestational diabetes mellitus (GDM) may change the profile of POPs in adipose tissue, probably due to an alteration in lipid metabolism. POPs investigated here may not be the cause of antenatal complication in pregnant women, and baby gender was not related to the pattern of contaminants in maternal adipose tissue. [ABSTRACT FROM AUTHOR]

Discusses the widespread distribution and environmental effects of the presence of polybrominated diphenyl ether (PBDE) flame retardants. Concerns on the ubiquity of PBDE in the environment; Health effects in humans and animals with low-level exposure to PBDE; Concerns on the presence of PBDE in mothers' milk. INSET: Ecolabels drive the search for substitutes..

A response by Purnendu K. Dasgupta, Andrea B. Kirk, Shin-Ichi Ohira, and Jason V. Dyke is presented to a letter to the editor about their article "Intake of Iodine and Perchlorate and Excretion in Human Milk” in an issue of 2008.

A letter to the editor is presented in response to the article “Intake of Iodine and Perchlorate and Excretion in Human Milk,” by P.K. Dasgupta, A.B. Kirk, J.V. Dyke, and S. Ohira in an issue of 2008.

The article discusses research that evaluates the correlation between a woman's daily intake of iodine and perchlorate and the concentrations of each in her breast milk. While a 20% proportion of iodine enters breast milk, this is true for 50% of perchlorate. Purnendu Dasgupta and colleagues of the University of Texas Arlington studied this correlation via the urine of mothers aged 24 - 34. In vitro contamination effects are discussed.

The first study of pentabromodiphenyl ethers (pentaBDEs) in Americans' breast milk finds levels 10-100 times higher than those recently measured in Europe. Studies indicate that some polybrominated diphenyl ethers (PBDEs) affect the thyroid systems of laboratory mice, which means that low-level exposures could subtly harm a developing human brain. Arnold Schecter and colleagues with the University of Texas Health Sciences Center, in Dallas, Texas, obtained breast milk from volunteers aged 20-41 at two health centers in Austin and Dallas. Measurements of up to 13 different PBDE congeners on 47 individuals, few of whom were occupationally exposed, yielded concentrations that varied from 6.2 to 419 parts-per-billion lipid. Most of the samples contained BDE-47, BDE-99, and BDE-153, which are common in the pentaBDE mixture used to flame retard upholstery foam.

The article presents the author's comments on emerging chemical contaminants. In September 2003, a study released by the Environmental Working Group (EWG), a nonprofit environmental research organization, caused a huge stir. Scientists working with EWG tested the breast milk of 20 women across the nation and found levels ranging from 9.5 to 1078 parts per billion of polybrominated diphenyl ethers (PBDEs). PBDEs are used as flame retardants for a wide variety of fabrics, draperies, clothing, and carpeting, and they are heavily used in the U.S., which has the world's toughest flame retardant standards. Undoubtedly, these chemicals save many lives by preventing fires, but the public has come to demand chemicals that do not move into the environment, their bodies, and their babies.