Comparisons of polybrominated diphenyl ethers levels in paired South Korean cord blood, maternal blood, and breast milk samples

Polybrominated diphenyl ethers (PBDEs), commonly used flame retardants, have been reported as potential endocrine disruptor and neurodevelopmental toxicants, thus giving rise to the public health concern. The goal of this study was to investigate the relationship between umbilical cord blood, maternal blood, and breast milk concentrations of PBDEs in South Korean. We assessed PBDE levels in paired samples of umbilical cord blood, maternal blood, and breast milk. The levels of seven PBDE congeners were measured in 21 paired samples collected from the Cheil Woman’s Hospital (Seoul, Korea) in 2008. We also measured thyroid hormones levels in maternal and cord blood to assess the association between PBDEs exposure and thyroid hormone levels. However, there was no correlation between serum thyroxin (T4) and total PBDEs concentrations. The total PBDEs concentrations in the umbilical cord blood, maternal blood, and breast milk were 10.7 ± 5.1 ng g⁻¹ lipid, 7.7 ± 4.2 ng g⁻¹ lipid, and 3.0 ± 1.8 ng g⁻¹ lipid, respectively. The ranges of total PBDE concentrations observed were 2.28-30.94 ng g⁻¹ lipid in umbilical cord blood, 1.8-17.66 ng g⁻¹ lipid in maternal blood, and 1.08-8.66 ng g⁻¹ lipid in breast milk. BDE-47 (45-73% of total PBDEs) was observed to be present dominantly in all samples, followed by BDE-153. A strong correlation was found for major BDE-congeners between breast milk and cord blood or maternal blood and cord blood samples. The measurement of PBDEs concentrations in maternal blood or breast milk may help to determine the concentration of PBDEs in infant.     

Phthalate exposure in pregnant women and their children in central Taiwan

Phthalate exposure was found to be associated with endocrine disruption, respiratory effects, reproductive and developmental toxicity. The intensive use of plastics may be increasing the exposure to phthalates in Taiwanese population, particularly for young children.We studied phthalate metabolites in pregnant women and their newborns in a prospective cohort from a medical center in Central Taiwan. One hundred maternal urine samples and 30 paired cord blood and milk samples were randomly selected from all of participants (430 pregnant women). Eleven phthalate metabolites (MEHP, 5OH-MEHP, 2cx-MEHP, 5cx-MEPP, 5oxo-MEHP, MiBP, MnBP, MBzP, OH-MiNP, oxo-MiNP, and cx-MiNP) representing the exposure to five commonly used phthalates (DEHP, di-isobutyl phthalate (DiBP), DnBP, BBP, DiNP) were measured in urine of pregnant women, cord serum and breast milk after delivery, and in urine of their children. Exposure was estimated with excretion factors and correlation among metabolites of the same parent compound. Thirty and 59 urinary samples from 2 and 5 years-old children were randomly selected from 185 children successfully followed.Total urinary phthalate metabolite concentration (geometric mean, μg L⁻¹) was found to be higher in 2-years-olds (398.6) and 5-years-olds (333.7) than pregnant women (205.2). Metabolites in urine are mainly from DEHP. The proportion of DiNP metabolites was higher in children urine (4.39 and 8.31%, ages 2 and 5) than in adults (0.83%) (p < 0.01). Compared to urinary levels, phthalate metabolite levels are low in cord blood (37.45) and milk (14.90). DEHP metabolite levels in women’s urine and their corresponding cord blood are significantly correlated. Compared to other populations in the world, DEHP derived metabolites in maternal urine were higher, while phthalate metabolite levels in milk and cord blood were similar. The level of phthalate metabolites in milk and cord blood were comparable to those found in other populations. Further studies of health effects related to DEHP and DiNP exposure are necessary for the children.     

Exposure assessment of French women and their newborn to brominated flame retardants: determination of tri- to deca- polybromodiphenylethers (PBDE) in maternal adipose tissue, serum, breast milk and cord serum

In the frame of a French monitoring program, tri- to deca- polybromodiphenylethers (PBDE) have been measured in maternal and cord serum, adipose tissue, and breast milk samples, collected from 93 volunteer women during caesarean deliveries. The seven major tri- to heptaBDE (BDE-28, 47, 99, 100, 153, 154, and 183) were detected in adipose tissue and breast milk with cumulated median values of 2.59 and 2.51 ng g⁻¹ l w. Nine highly brominated octa- to decaBDE (BDE-196, 197, 201, 202, 203, 206, 207, 208 and 209) was performed in the same samples, with cumulated median values of 2.73 and 3.39 ng g⁻¹ l w in adipose tissue and breast milk, respectively. At this opposite, median levels of octa- to decaBDE in maternal and cord serum appeared significantly higher than the levels of tri- to heptaBDE in the same matrices, i.e. 8.85 and 12.34 versus 0.98 and 0.69 ng g⁻¹ l w, respectively.     

Organochlorine pesticide in fresh and pasteurized cow's milk from Kampala markets

Fresh and pasteurized milk samples from Kampala markets were analyzed for organochlorine pesticides using a gas chromatograph equipped with an electron capture detector. Five organochlorine pesticides, namely; aldrin, dieldrin, endosulfan, lindane, DDT and its metabolites were detected in the milk samples and confirmed with a gas chromatograph equipped with a mass spectrometer [GC-MS]. The mean values are expressed in mg kg⁻¹ milk fat (mf) basis. The mean concentration in the fresh milk (n = 54) were: 0.026 ± 0.003 mg kg⁻¹ mf; 0.002 ± 0.0003 mg kg⁻¹, below the detection limit; 0.007 ± 0.003 mg kg⁻¹, 0.009 ± 0.002 mg kg⁻¹ milk fat for lindane, endosulfan dieldrin and aldrin, respectively. The mean concentrations of p,p′-DDE; p,p′-DDT and o,p′-DDT were 0.009 ± 0.002 mg kg⁻¹; 0.033 ± 0.007 mg kg⁻¹ and 0.008 ± 0.001 mg kg⁻¹ mf, respectively in the fresh milk samples.In the pasteurized milk samples (n = 47), the mean concentrations recorded were: 0.008 ± 0.003 mg kg⁻¹, 0.025 ± 0.004 mg kg⁻¹, and 0.007 ± 0.001 mg kg⁻¹, respectively for p,p′-DDE; p,p′-DDT and o,p′-DDT.Alpha and beta-endosulfan recorded the concentration below the detection limit and the mean of 0.022 ± 0.001 mg kg⁻¹ mf, 0.005 ± 0.002 mg kg⁻¹ mf, and 0.006 ± 0.0002 mg kg⁻¹ mf, respectively for lindane, dieldrin and aldrin. Although, most of the residues detected were above the residue limits set by the FAO/WHO (2008), bioaccumulation of these residues is likely to pose health risks to the consumers of milk in Uganda.     

Persistent organic pollutants (POPs) in human milk: A biomonitoring study in rural areas of Flanders (Belgium)

To collect information on the concentrations of persistent organic pollutants (POPs) in the rural areas in Flanders (Belgium), 84 breastfeeding mothers were recruited in rural communities in East and West Flanders and Flemish Brabant in 2009-2010. Polychlorinated biphenyl (PCB) congeners, organochlorine pesticides, brominated flame retardants, perfluorinated compounds, polychlorinated dibenzodioxines and dibenzofurans, and dioxin-like PCBs were measured in individual milk samples and in a pooled milk sample, while some additional pollutants were only measured in the pooled sample. For most pollutants, the concentrations in this study were lower or comparable to the concentrations measured in the pooled Belgian sample of the WHO human milk study of 2006, except for the pesticides dichlorodiphenyltrichloroethane DDT (+25% for ΣDDT and metabolites) and trans-nonachlor (+94%), and for the brominated flame retardant hexachlorocyclododecane HBCD (+153%). Perfluorinated compounds were for the first time determined in human milk samples from Belgium and the concentrations were comparable to those from other European countries. Also, interesting associations were found between the concentrations of POPs measured in human milk and personal characteristics as well as dietary habits of the study population. PFOS en PFOA concentrations were significantly higher in milk of primiparous participants compared to mothers who gave birth to their second child. Lower brominated PBDE congeners increased with increasing BMI of the mothers (p = 0.01 for BDE 47, p = 0.02 for BDE 99 and p = 0.02 for BDE 100). Participants consuming milk or dairy products daily had significant higher concentrations of ΣDDTs (p = 0.03) and oxychlordane (p = 0.047) in their human milk samples.     

Urinary and serum metabolites of di-n-pentyl phthalate in rats

Di-n-pentyl phthalate (DPP) is used mainly as a plasticizer in nitrocellulose. At high doses, DPP acts as a potent testicular toxicant in rats. We administered a single oral dose of 500 mg kg⁻¹ bw of DPP to adult female Sprague-Dawley rats (N = 9) and collected 24-h urine samples 1 d before and 24- and 48-h after DPP was administered to tentatively identify DPP metabolites that could be used as exposure biomarkers. At necropsy, 48 h after dosing, we also collected serum. The metabolites were extracted from urine or serum, resolved with high performance liquid chromatography, and detected by mass spectrometry. Two DPP metabolites, phthalic acid (PA) and mono(3-carboxypropyl) phthalate (MCPP), were identified by using authentic standards, whereas mono-n-pentyl phthalate (MPP), mono(4-oxopentyl) phthalate (MOPP), mono(4-hydroxypentyl) phthalate (MHPP), mono(4-carboxybutyl) phthalate (MCBP), mono(2-carboxyethyl) phthalate (MCEP), and mono-n-pentenyl phthalate (MPeP) were identified based on their full scan mass spectrometric fragmentation pattern. The ω − 1 oxidation product, MHPP, was the predominant urinary metabolite of DPP. The median urinary concentrations (μg mL⁻¹) of the metabolites in the first 24 h urine collection after DPP administration were 993 (MHPP), 168 (MCBP), 0.2 (MCEP), 222 (MPP), 47 (MOPP), 26 (PA), 16 (MPeP), and 9 (MCPP); the concentrations of metabolites in the second 24 h urine collection after DPP administration were significantly lower than in the first collection. We identified some urinary metabolic products in the serum, but at much lower levels than in urine. Because of the similarities in metabolism of phthalates between rats and humans, based on our results and the fact that MHPP can only be formed from the metabolism of DPP, MHPP would be the most adequate DPP exposure biomarker for human exposure assessment. Nonetheless, based on the urinary levels of MHPP, our preliminary data suggest that human exposure to DPP in the United States is rather limited.     

Hydrolysis of di-n-butyl phthalate, butylbenzyl phthalate and di(2-ethylhexyl) phthalate in human liver microsomes

Diester phthalates are industrial chemicals used primarily as plasticizers to import flexibility to polyvinylchloride plastics. In this study, we examined the hydrolysis of di-n-butyl phthalate (DBP), butylbenzyl phthalate (BBzP) and di(2-ethylhexyl) phthalate (DEHP) in human liver microsomes. These diester phthalates were hydrolyzed to monoester phthalates (mono-n-butyl phthalate (MBP) from DBP, mono-n-butyl phthalate (MBP) and monobenzyl phthalate (MBzP) from BBzP, and mono(2-ethylhexyl) phthalate (MEHP)) by human liver microsomes. DBP, BBzP and DEHP hydrolysis showed sigmoidal kinetics in V-[S] plots, and the Hill coefficient (n) ranged 1.37-1.96. The S₅₀, V_max and CL_max values for DBP hydrolysis to MBP were 99.7 μM, 17.2 nmol min⁻¹ mg⁻¹ protein and 85.6 μL min⁻¹ mg⁻¹ protein, respectively. In BBzP hydrolysis, the values of S₅₀ (71.7 μM), V_max (13.0 nmol min⁻¹ mg⁻¹ protein) and CL_max (91.3 μL min⁻¹ mg⁻¹ protein) for MBzP formation were comparable to those of DBP hydrolysis. Although the S₅₀ value for MBP formation was comparable to that of MBzP formation, the V_max and CL_max values were markedly lower (<3%) than those for MBzP formation. The S₅₀, V_max and CL_max values for DEHP hydrolysis were 8.40 μM, 0.43 nmol min⁻¹ mg⁻¹ protein and 27.5 μL min⁻¹ mg⁻¹ protein, respectively. The S₅₀ value was about 10% of DBP and BBzP hydrolysis, and the V_max value was also markedly lower (<3%) than those for DBP hydrolysis and MBzP formation for BBzP hydrolysis. The ranking order of CL_max values for monoester phthalate formation in DBP, BBzP and DEHP hydrolysis was BBzP to MBzP ? DBP to MBP > DEHP to MEHP > BBzP to MBP. These findings suggest that the hydrolysis activities of diester phthalates by human liver microsomes depend on the chemical structure, and that the metabolism profile may relate to diester phthalate toxicities, such as hormone disruption and reproductive effects.     

Detection of dicofol and related pesticides in human breast milk from China, Korea and Japan

Previously, we demonstrated that the concentrations of DDTs were greater in breast milk collected from Chinese mothers than from Japanese and Korean mothers. To investigate dicofol as a possible source of the DDTs in human breast milk, we collected breast milk samples from 2007 to 2009 in China (Beijing), Korea (Seoul, Busan) and Japan (Sendai, Takarazuka and Takayama). Using these breast milk samples, we quantified the concentrations of dichlorobenzophenone, a pyrolysis product of dicofol (simply referred to as dicofol hereafter), dichlorodiphenyltrichloroethane and its metabolites (DDTs) using GC-MS. Overall, 12 of 14 pooled breast milk samples from 210 mothers contained detectable levels of dicofol (>0.1 ng g⁻¹ lipid). The geometric mean concentration of dicofol in the Japanese breast milk samples was 0.3 ng g⁻¹ lipid and significantly lower than that in Chinese (9.6 ng g⁻¹ lipid) or Korean breast milk samples (1.9 ng g⁻¹ lipid) (p < 0.05 for each). Furthermore, the ΣDDT levels in breast milk from China were 10-fold higher than those from Korea and Japan. The present results strongly suggest the presence of extensive emission sources of both dicofol and DDTs in China. However, exposure to dicofol cannot explain the large exposure of Chinese mothers to DDTs because of the trace levels of dicofol in the ΣDDTs. In the present study, dicofol was confirmed to be detectable in human breast milk. This is the first report to identify dicofol in human samples.     

The relationship between persistent organic pollutants in maternal and neonatal tissues and immune responses to allergens: A novel exploratory study

BACKGROUND: Modern persistent organic pollutants (POPs) contamination are logical candidates in the investigation of the, as yet, unexplained association between allergic disease and progressive industrialisation. POPs have been detected in human cord blood, placental tissues and breast milk, and the reported association between cord blood IgE levels and cord/placental POP levels has raised concerns about potential immunological effects in early life. METHODS: The initial aim of this study was to determine if POPs were detectable in maternal blood, cord blood, placental tissues, adipose tissue and breast milk samples from randomly selected Western Australian women (n = 31), where allergic disease is epidemic. Gas chromatography was used to detect polychlorinated biphenyl compounds [PCBs] (as Aroclor 1232, 1254, 1260) and organochlorine (OC) pesticides, including p,p'-DDT, p,p'-DDE, hexachlorobenzene (HCB), lindane, heptachlor epoxide, dieldrin and chlordane. Secondly, we assessed the relationship between POP levels detected in vivo and maternal and neonatal responses (cytokine and lymphoproliferation) to allergens and mitogens. RESULTS: Low level POP contamination was detected in adipose tissue and breast milk (but not in cord blood, maternal blood or placental tissues). The most ubiquitous compound found in over 90% of adipose tissues samples was a OC metabolite of DDT, p,p'-DDE (median 0.07 mg/kg; interquartile range [IQR] 0.05-0.12). However, the majority of other OC compounds were not detectable and PCB were not detectable in any samples. The three main residues detected in breast milk were p,p'-DDE (0.003 mg/l; 0.001-0.009), dieldrin (0.001 mg/l; 0.001-0.046) and HCB (0.001 mg/l; 0.001-0.001). These levels are significantly lower than reported over 20 years ago. There were no consistent relationships between POP levels in vivo and maternal or infant responses, with the exception of a significant inverse association (Spearman rank correlation: r = -0.406, p = 0.049) between maternal adipose tissue levels of OC p,p'-DDE and maternal T helper cell Type 1 interferon [IFN] gamma to mitogens. CONCLUSION: This study provides the first evidence (in Australia) since the early 1990's that adipose OC levels have continued to fall. The negligible levels in this randomly selected group are significantly lower than those previously recorded, suggesting that POP contamination (at biologically relevant levels) is not likely to be a major contributing factor in the increasing rates of allergy in Western Australia. However, the relationship between Th1 immune function and OC contamination is consistent with other reports and is worth investigating as a relevant factor in populations where OC contamination is greater.     

Levels and profiles of long-chain perfluorinated carboxylic acids in human breast milk and infant formulas in East Asia

In this study, 90 human breast milk samples collected from Japan, Korea, and China were analyzed for perfluorooctanoic acid (PFOA) (C8), perfluorononanoic acid (PFNA) (C9), perfluorodecanoic acid (PFDA) (C10), perfluoroundecanoic acid (PFUnDA) (C11), perfluorododecanoic acid (PFDoDA) (C12), and perfluorotridecanoic acid (PFTrDA) (C13). In addition, infant formulas (n = 9) obtained from retail stores in China and Japan were analyzed. PFOA was the predominant compound and was detected in more than 60% of samples in all three countries. The PFOA, PFNA, PFDA, and PFUnDA levels in Japan were significantly higher than those in Korea and China (p < 0.05). The PFTrDA level was highest in Korea (p < 0.05). The median PFOA concentrations were 89 pg mL⁻¹ (48% of total perfluorinated carboxylic acids (PFCAs) (C8-C13)) in Japan, 62 pg mL⁻¹ (54%) in Korea, and 51 pg mL⁻¹ (61%) in China. The remaining ∑PFCAs (C9-C13) were 95 pg mL⁻¹ in Japan, 52 pg mL⁻¹ in Korea, and 33 pg mL⁻¹ in China. Among the long-chain PFCAs, odd-numbered PFCAs were more frequently detected than even-numbered PFCAs, except for PFDA in Japan. There were no evident correlations between the mother’s demographic factors and the PFCA concentrations. PFOA, PFNA, and PFDA were frequently detected in both Japan and China, but there were no significant differences between the two countries. The total PFCA concentrations in the infant formulas were lower than those in the breast milk samples in Japan (p < 0.05), but not in China (p > 0.05). In conclusion, various PFCAs were detected in human breast milk samples from East Asian countries.     

Polychlorinated biphenyls (PCBs) residues in milk from an agroindustrial zone of Tuxpan, Veracruz, Mexico

The coasts of the Gulf of Mexico are zones exposed to the exploration and exploitation of petroleum sources, and the products generated in agricultural zones may become contaminated by persistent organic pollutants (POPs). The objective of the present study was to evaluate the presence of polychlorinated biphenyl compounds (PCBs) in milk from dairy production units near sources of environmental pollutants. It was confirmed that the seven congeners of nondioxin-like PCBs (NDL-PCBs) are present in milk where compounds PCB101, PCB118, PCB153 and PCB180 appear in 100% of the samples analyzed, the rank of concentration for the sum of the seven congeners fluctuating between 2.6 and 26 ng g⁻¹ with a median of 6 ng g⁻¹. None of the samples surpassed the provisional value established by the EU of 40 ng g⁻¹ of milk fat for the sum of the seven congeners, indicator that was not affected by the season of the year (p < 0.05), whose median of 8.6 ng g⁻¹ and 6.3 ng g⁻¹ for rain and drought respectively. The concentrations of NDL-PCBs found in milk do not represent a problem for human health; however, they alert the existence of spontaneously generated, uncontrolled sources that may represent a potential danger for human and animal health.     

Vapor-phase concentrations of PAHs and their derivatives determined in a large city: Correlations with their atmospheric aerosol concentrations

Thirteen PAHs, five nitro-PAHs and two hydroxy-PAHs were determined in 55 vapor-phase samples collected in a suburban area of a large city (Madrid, Spain), from January 2008 to February 2009. The data obtained revealed correlations between the concentrations of these compounds and a series of meteorological factors (e.g., temperature, atmospheric pressure) and physical–chemical factors (e.g., nitrogen and sulfur oxides). As a consequence, seasonal trends were observed in the atmospheric pollutants. A “mean sample” for the 14-month period would contain a total PAH concentration of 13 835 ± 1625 pg m⁻³ and 122 ± 17 pg m⁻³ of nitro-PAHs. When the data were stratified by season, it emerged that a representative sample of the coldest months would contain 18 900 ± 2140 pg m⁻³ of PAHs and 150 ± 97 pg m⁻³ of nitro-PAHs, while in an average sample collected in the warmest months, these values drop to 9293 ± 1178 pg m⁻³ for the PAHs and to 97 ± 13 pg m⁻³ for the nitro-PAHs. Total vapor phase concentrations of PAHs were one order of magnitude higher than concentrations detected in atmospheric aerosol samples collected on the same dates. Total nitro-PAH concentrations were comparable to their aerosol concentrations whereas vapor phase OH-PAHs were below their limits of the detection, indicating these were trapped in airborne particles.     

Determination of chlorinated pesticides, polychlorinated biphenyls, and polybrominated diphenyl ethers in human milk from Bizerte (Tunisia) in 2010

Thirty persistent organohalogen compounds including organochlorine pesticides (OCPs), polychlorinated biphenyls (PCBs), and polybrominated diphenyl ethers (PBDEs) were determined in breast milk samples (n = 36) of primipara and multipara mothers from Bizerte in 2010. The analytical procedure involved the application of liquid-liquid extraction and gas chromatography with electron capture detector (GC-ECD) or mass spectrometry detector (GC-MS) for identification and quantification. Organohalogen compounds were found in all the analyzed samples, with predominance of p,p′-DDE, p,p′-DDT, p,p′-DDD, HCB and PCBs. The mean concentration of ∑DDTs in breast milk was 1163.9 ng g⁻¹ lipid wt. The ratio of p,p′-DDE/p,p′-DDT was low, suggesting that there is fresh intake of commercial DDT products in Bizerte. The mean levels of HCB and PCB were 286.8 and 331.2 ng g⁻¹ lipid wt respectively. These results were compared with the levels obtained in a previous study carried out in the same area in 2003. A general decrease of ∑DDTs levels and an increase of PCB levels were observed. Among the 10 PBDE congeners evaluated, BDE-28, BDE-47, BDE-99, BDE-66, BDE-138, BDE-100, BDE-154, BDE-153, and BDE-183 were detected in the analyzed samples at different frequency. The total PBDE concentrations ranged from 2.5 to 22.6 ng g⁻¹ lipid wt in the samples, with a mean and median value of 10.7 and 9.8 ng g⁻¹ lipid wt respectively. To our knowledge, this is the first data of PBDEs in Tunisian human milk. The present study shows that age and parity are factors influencing the levels of some organohalogen compounds in human milk.     

Human maternal and umbilical cord blood concentrations of polybrominated diphenyl ethers

Polybrominated diphenyl ethers (PBDEs), widely used as flame retardants in commercial products, have become ubiquitous environmental contaminants. Although adult human exposure to PBDEs is well documented, developmental exposure is less well characterized. The objectives of this study were to measure maternal and fetal exposure to nine PBDE congeners and to investigate potential associations with birth weight. PBDE congeners were quantified in maternal serum at 24-28 weeks of pregnancy, delivery, and umbilical cord serum (UCS) by gas chromatography-mass spectrometry (GC/MS/MS). Complete blood sample sets were obtained from 97 pregnant women (mean age 33.1 ± 0.5 years). PBDE-28, -47 and -99 were quantified in all samples tested and PBDE-47 was the most abundant congener measured in both maternal (mid-pregnancy and delivery samples geometric mean = 26.9 and 26.9, respectively) and UCS (GM = 56.0 ng g⁻¹ lipid). The UCS concentration for all congeners with the exception of PBDE-153 was higher vs. maternal delivery samples (p < 0.001). Only the UCS concentration of PBDE-17 and -99 were significantly associated (β = −49.860, p = 0.032, and β = −3.645, p = 0.05) with birth weight. However, after adjustment for potential confounders only the association between PBDE-99 and birth weight remained significant (β = −3.951 and p = 0.016). We conclude that: the fetus is exposed to PBDEs from at least the second trimester of pregnancy onward; PBDE congeners are higher in UCS compared to maternal serum samples collected at delivery; and that developmental PBDE exposure is potentially associated with lower birth weight.     

Comparative analysis of trace contaminants in leachates before and after a pre-oxidation using a solar photo-Fenton reaction

Sanitary landfill leachates are a complex mixture of high-strength organic and inorganic persistent contaminants, which constitute a serious environmental problem. In this study, trace contaminants present in leachates were investigated by gas chromatography-mass spectrometry and gas chromatography-flame ionization detector before and after a pre-oxidation step using a solar photo-Fenton process. More than 40 organic compounds were detected and identified as benzene (0.09?±?0.07 mg?L^-1), trichlorophenol (TCP) (0.18?±?0.12 mg?L^-1), phthalate esters (Di-n-butyl phthalate (DBP), Butyl benzyl phthalate (BBP), Di(2-ethylhexyl) phthalate (DEHP)) (DBP: 0.47?±?0.01 mg?L^-1; BBP: 0.36?±?0.02 mg?L^-1; DEHP: 0.18?±?0.01 mg?L^-1), among others. Toluene, pentachlorophenol, dimethyl phthalate, diethyl phthalate, and Di-n-octyl phthalate were never detected in any of the samples. After the photo-Fenton treatment process, TCP decreased to levels below its detection limit, benzene concentration increased approximately three times, and DBP concentration decreased about 77 % comparatively to the raw leachate sample. The solar photo-Fenton process was considered to be very efficient for the treatment of sanitary landfill leachates, leading to the complete elimination of 24 of the detected micropollutants to levels below their respective detection limits and low to significant abatement of seven other organic compounds, thus resulting in an increase of the leachate biodegradability.     

Levels of PCDD/Fs,PCBs and PBDEs in breast milk of women living in the vicinity of a hazardous waste incinerator: Assessment of the temporal trend

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 hazardous waste incinerator (HWI) in Catalonia, Spain. The results were compared with the levels obtained in previous surveys carried out in the same area in 1998 (baseline study), 2002 and 2007. The current total concentrations of 2,3,7,8-chlorinated PCDD/Fs in breast milk ranged from 18 to 126 pg g⁻¹ fat (1.1–12.3 pg WHO₂₀₀₅-TEQ_PCDD/F), while the total levels of PCBs ranged from 27 to 405 pg g⁻¹ fat (0.7–5.3 pg WHO₂₀₀₅-TEQ_PCB). In turn, PBDE concentrations (sum of 15 congeners) ranged 0.3–5.1 g g⁻¹ fat, with a mean value of 1.3 ng g⁻¹ fat. A general decrease in the concentrations for PCDD/Fs, both planar and total PCBs, and PBDEs in breast milk was observed. The levels of PCDD/Fs, PCBs, and PBDEs in milk of women living in urban zones were higher than those corresponding to industrial zones (41%, 26%, and 8%, respectively). For PCDD/Fs and PCBs, the current decreases are in accordance with the reduction in the dietary intake of these pollutants that we have also observed in recent studies carried out in the same area of study.     

Comparative survey of levels of chlorinated cyclodiene pesticides in breast milk from some cities of China, Korea and Japan

Exposure of mothers to organochlorine pesticides (OCPs) was assessed by measuring the levels of 20 OCPs in 70 human breast milk samples pooled from 210 individuals from China, Korea and Japan. The OCPs were analyzed using gas chromatography/mass spectrometry (GC/MS) in electron capture negative ionization (ECNI) monitoring. The results showed that β-hexachlorocyclohexane and hexachlorobenzene were one order of magnitude higher in China than in the other nations, whereas chlordanes and polychlorinated biphenyl levels were highest in Japan. Heptachlor epoxide, dieldrin, endrin, toxaphenes and mirex were detected in most samples, and levels of these chemicals were significantly higher in Japan (0.8-4.5 ng g⁻¹ lipid), followed by Korea (0.2-4.7 ng g⁻¹ lipid), and lowest in China (less than 1.0 ng g⁻¹ lipid). α- and β-endosulfans were detected at a range of 0.9-1.5 ng g⁻¹ lipid levels in all samples analyzed, and their levels were higher in Korean than in Chinese samples.     

Cytogenetic status of human lymphocytes after exposure to low concentrations of p,p'-DDT, and its metabolites (p,p'-DDE, and p,p'-DDD) in vitro

Despite that the use of DDT has been restricted for more than 40 years to malaria affected areas, low doses of this pesticide and its metabolites DDE and DDD can be found in the environment around the world. Although it has been shown that these pollutants induce cell and DNA damage, the mechanisms of their cytogenotoxic activity remains largely unknown. This study looks into their possible genotoxic effects, at doses that can be found in body fluids, on human lymphocytes using the cytokinesis-block micronucleus assay and the comet assay. After exposure for 1, 6, and 24 h compounds p,p′-DDT (0.1 μg mL⁻¹), p,p′-DDE (4.1 μg mL⁻¹), and p,p′-DDD (3.9 μg mL⁻¹) showed increase in DNA damage. The most significant results were observed at exposure period of 24 h where number of micronucleated cells increased from control 2.5 ± 0.71 to 23.5 ± 3.54, 13.5 ± 0.71, and 16.5 ± 6.36 for DDT, DDE, and DDD, respectively. Similar effect was observed using comet test where the percentage of DNA in comets tail increased from control 1.81 ± 0.16 to 17.24 ± 0.55, 11.21 ± 0.56 and 9.28 ± 0.50 for each compound, respectively. At the same time Fpg-comet assay failed to report induction of oxidative DNA damage of these pollutants. Additionally, the type of cell death was determined using diffusion assay and necrosis dominated. Our findings suggest that even at low concentrations, these pesticides could induce cytogenetic damage to human peripheral blood lymphocytes and in that manner have the impact on human health as well.     

Characterization of extractable and non-extractable polycyclic aromatic hydrocarbons in soils and sediments from the Pearl River Delta, China

Formation of bound residues of pollutants in soils and sediments is an important process to control the fate of pollutants in the environment. The most of bound residue is not solvent extractable. In this paper, we measured both extractable and non-extractable polycyclic aromatic hydrocarbons (PAHs) in different organic matter fractions of samples from the Pearl River Delta, China. Non-extractable PAHs concentration was 234.45-1424.57 μg/kg and accounted for 33.78-57.44% of total PAHs. 2-3 Ring PAHs were the dominant species and differed in concentration substantially between the samples. The atomic ratio of PAHs over organic-C in the fractions ordered as solvent soluble organic matter > humin > humic acids, matching the content of aliphatic moieties in the fractions of organic matter. The ratio of extractable and non-extractable PAHs may relate to the aging process of PAHs in soil and sediment.     

PAH-sequestration capacity of granular and powder activated carbon amendments in soil, and their effects on earthworms and plants

A field lysimeter study was carried out to investigate whether the amendment of 2% powder and granular activated carbon (PAC and GAC) to a soil with moderate PAH contamination had an impact on the PAH bioaccumulation of earthworms and plants, since AC is known to be a strong sorbent for organic pollutants. Furthermore, secondary effects of AC on plants and earthworms were studied through growth and nutrient uptake, and survival and weight gain. Additionally, the effect of AC amendments on soil characteristics like pH, water holding capacity, and the water retention curve of the soil were investigated. Results show that the amendment of 2% PAC had a negative effect on plant growth while the GAC increased the growth rate of plants. PAC was toxic to earthworms, demonstrated by a significant weight loss, while the results for GAC were less clear due to ambiguous results of a field and a parallel laboratory study. Both kinds of AC significantly reduced biota to soil accumulation factors (BSAFs) of PAHs in earthworms and plants. The GAC reduced the BSAFs of earthworms by an average of 47 ± 44% and the PAC amendment reduced them by 72 ± 19%. For the investigated plants the BSAFs were reduced by 46 ± 36% and 53 ± 22% by the GAC and PAC, respectively.