PVC flooring at home and uptake of phthalates in pregnant women.

Phthalates are used as plasticizers in polyvinyl chloride (PVC) materials and it is known that phthalates may migrate into the surrounding environment and then become a source for human uptake. The aim of the study was to investigate whether residential PVC flooring was related to the urinary levels of phthalate metabolites determined in pregnant women. The data were from the Swedish SELMA study where sampling was conducted during the time period 2007-2010. Spot urine samples from 1674 women at the end of the first trimester were analyzed for 14 metabolites from seven phthalates and one phthalate alternative. Data on flooring material in the kitchen and the parents' bedrooms as well as potential confounders were collected by postal questionnaires at the same time as the urine samples were taken. Multiple regression modeling by least square geometric mean and weighted quantile sum regression was applied to log-transformed and creatinine-adjusted phthalate metabolite concentrations adjusted for potential confounders from questionnaire data. This study has found significantly higher urinary levels of the BBzP metabolite (MBzP) in pregnant women living in homes with PVC flooring as compared to homes with other flooring materials.

Amniotic Fluid INSL3 Measured During the Critical Time Window in Human Pregnancy Relates to Cryptorchidism, Hypospadias, and Phthalate Load: A Large Case-Control Study.

The period of the first to second trimester transition in human pregnancy represents a sensitive window for fetal organogenesis, particularly in regard to the development of the male reproductive system. This is a time of relative analytical inaccessibility. We have used a large national biobank of amniotic fluid samples collected at routine amniocentesis to determine the impacts of exogenous endocrine disruptor load on specific fetal biomarkers at this critical time. While adrenal and testicular steroids are highly correlated, they are also mostly positively influenced by increasing phthalate load, represented by the metabolites 7cx-MMeHP and 5cx-MEPP, by perfluorooctane sulfonate (PFOS) exposure, and by smoking, suggesting an adrenal stress response. In contrast, the testis specific biomarkers insulin-like peptide 3 (INSL3) and androstenedione are negatively impacted by the phthalate endocrine disruptors. Using a case-control design, we show that cryptorchidism and hypospadias are both significantly associated with increased amniotic concentration of INSL3 during gestational weeks 13-16, and some, though not all steroid biomarkers. Cases are also linked to a specifically increased variance in the Leydig cell biomarker INSL3 compared to controls, an effect exacerbated by maternal smoking. No influence of phthalate metabolites or PFOS was evident on the distribution of cases and controls. Considering that several animal and human studies have shown a negative impact of phthalate load on fetal and cord blood INSL3, respectively, the present results suggest that such endocrine disruptors may rather be altering the relative dynamics of testicular development and consequent hormone production, leading to a desynchronization of tissue organization during fetal development. Being born small for gestational age appears not to impact on the testicular biomarker INSL3 in second trimester amniotic fluid.

Occupational exposure to asphalt mixture during road paving is related to increased mitochondria DNA copy number: a cross-sectional study.

BACKGROUND: Asphalt workers are exposed to polyaromatic hydrocarbons (PAHs) from hot mix asphalt via both inhalation and dermal absorption. The use of crumb rubber modified (CRM) asphalt may result in higher exposure to PAHs and more adverse effects. Our aim is to assess occupational exposure to PAHs from conventional and CRM asphalt paving by measuring PAH metabolites in urine, and to investigate the effects on mitochondrial DNA copy number (mtDNAcn) and telomere length. METHODS: We recruited 116 workers paving conventional asphalt, 51 workers paving CRM asphalt and 100 controls in Sweden, all males. A repeated-measures analysis included 31 workers paving both types of asphalt. Urine and blood samples were collected pre-working on Monday morning and post-working on Thursday afternoon after 4 days working. PAH metabolites: 1-hydroxypyrene (1-OH-PYR) and 2-hydroxyphenanthrene (2-OH-PH) were measured in urine by LC-MS/MS. Relative mtDNAcn and telomere length were measured by quantitative PCR. RESULTS: Conventional and CRM asphalt workers showed higher 1-OH-PYR and 2-OH-PH than controls (p < 0.001 for all). Relative mtDNAcn were 0.21 units (p < 0.001) higher in conventional asphalt workers and 0.13 units (p = 0.010) higher in CRM asphalt workers compared to controls. Relative telomere length did not differ across occupational groups, but it was positively associated with increment of 2-OH-PH (ß = 0.075, p = 0.037) in asphalt workers. The repeated-measures analysis showed no difference in either increment of 1-OH-PYP, or changes in effect biomarkers (mtDNAcn or telomere length) between paving with conventional and CRM asphalt. Increment of 2-OH-PH was smaller after paving with CRM asphalt. CONCLUSIONS: Road asphalt paving in open areas resulted in PAHs exposure, as shown by elevation of PAH metabolites in urine. Asphalt workers may experience oxidative stress, evidenced by alternation in mtDNAcn; however the effects could not be fully explained by exposure to PAHs from the asphalt mixture.

Impact of Di-2-Ethylhexyl Phthalate Metabolites on Male Reproductive Function: a Systematic Review of Human Evidence.

PURPOSE OF REVIEW: The purpose of this review is to systematically review the literature linking di-2-ethylhexyl phthalate (DEHP) exposure with effects on reproductive health in adult males. RECENT FINDINGS: Thirty-three papers were included of which 28 were cross-sectional. Twenty-one papers investigated semen samples, 18 investigated reproductive hormones, and three studies investigated time to pregnancy. Studies revealed some but inconsistent indications that higher urinary DEHP metabolite levels are associated with an increase in the proportion of spermatozoa with damaged DNA and to a decrease in sperm concentration and motility. A negative association between DEHP metabolites and testosterone levels was more consistent. DEHP metabolites do not seem to be associated with a delay in time to pregnancy, but data are sparse. The studies on DEHP exposure and reproductive biomarkers in men converge to support the hypothesis that DEHP exposure is related to impaired male reproductive function. Longitudinal studies are needed to establish if the observed associations are causal.

Prenatal phthalate exposure was associated with croup in Swedish infants.

AIM: This study examined whether prenatal phthalate exposure was associated with lower or upper airway inflammation in infants. METHODS: From 2007 to 2010, we used liquid chromatography-tandem mass spectrometry, adjusted for creatinine, to analyse 14 phthalate metabolites and one phthalate replacement in the urine of 1062 Swedish mothers at a median of 10 weeks of pregnancy. This was used to determine any associations between prenatal phthalate exposure and croup, wheezing or otitis in their offspring until 12 months of age, using logistic regression, adjusted for potential confounders. RESULTS: There were significant associations between phthalate metabolites of butyl-benzyl phthalate (BBzP) and di-ethyl-hexyl phthalate (DEHP) concentrations in maternal prenatal urine and croup in 1062 infants during the first year of life, when adjusted for potential confounders. A dose-response relationship was found between prenatal phthalates exposure and maternal reported croup in the children, with a significant association in boys. There was no clear indication with regard to associations between prenatal phthalate exposure and wheezing or otitis media in the children during the first year of life. CONCLUSION: Our analysis suggests that exposure to BBzP and DEHP phthalates was associated with maternal reports of croup in infants up to 12 months of age.

Prenatal and Postnatal PCB-153 and p,p'-DDE Exposures and Behavior Scores at 5­9 Years of Age among Children in Greenland and Ukraine.

BACKGROUND: Studies have reported some evidence of adverse effects of organochlorine exposures on child development, but the results have been inconsistent, and few studies have evaluated associations with child behavior. OBJECTIVE: We investigated the association between prenatal and early-life exposures to 2,2',4,4',5,5'-hexachlorobiphenyl (PCB-153) and 1,1-dichloro-2,2-bis(p-chlorophenyl)-ethylene (p,p'-DDE) and behaviors in children between 5 and 9 y of age. METHODS: In the Biopersistent organochlorines in diet and human fertility: Epidemiologic studies of time to pregnancy and semen quality in Inuit and European populations (INUENDO) cohort, consisting of mother-child pairs from Greenland and Ukraine (n=1,018), maternal serum PCB-153 and p,p'-DDE concentrations were measured during pregnancy, and cumulative postnatal exposures during the first 12 months after delivery were estimated using a pharmacokinetic model. Parents completed the Strengths and Difficulties Questionnaire (SDQ), and children's behaviors were dichotomized as abnormal (high) versus normal/borderline for five SDQ subscales and the total difficulties score. RESULTS: The total difficulties score, an overall measure of abnormal behavior, was not clearly associated with pre- or postnatal exposures to PCB-153 or to p,p'-DDE. However, pooled adjusted odds ratios (ORs) for high conduct problem scores with a doubling of exposure were 1.19 (95% CI: 0.99, 1.42) and 1.16 (95% CI: 0.96, 1.41) for pre- and postnatal PCB-153, respectively, and 1.25 (95% CI: 1.04, 1.51) and 1.24 (95% CI: 1.01, 1.51) for pre- and postnatal p,p'-DDE, respectively. Corresponding ORs for high hyperactivity scores were 1.24 (95% CI: 0.94, 1.62) and 1.08 (95% CI: 0.81, 1.45) for pre- and postnatal PCB-153, respectively, and 1.43 (95% CI: 1.06, 1.92) and 1.27 (95% CI: 0.93, 1.73) for pre- and postnatal p,p'-DDE, respectively. CONCLUSION: Prenatal and early postnatal exposures to p,p'-DDE and PCB-153 were associated with a higher prevalence of abnormal scores for conduct and hyperactivity at 5­9 y of age in our study population. These findings provide further support for the importance of minimizing organochlorine exposures to young children and to women of childbearing age. https://doi.org/10.1289/EHP553.

Concentration of perfluorinated compounds and cotinine in human foetal organs, placenta, and maternal plasma.

BACKGROUND: Perfluoroalkyl substances (PFASs) are bio-accumulative pollutants, and prenatal exposure to PFASs is believed to impact human foetal development and may have long-term adverse health effects later in life. Additionally, maternal cigarette smoking may be associated with PFAS levels. Foetal exposure has previously been estimated from umbilical cord plasma, but the actual concentration in foetal organs has never been measured. OBJECTIVES: The concentrations of 5 PFASs and cotinine - the primary metabolite of nicotine - were measured in human foetuses, placentas, and maternal plasma to evaluate to what extent these compounds were transferred from mother to foetus and to determine if the PFAS concentrations were associated with maternal cigarette smoking. METHODS: Thirty-nine Danish women who underwent legal termination of pregnancy before gestational week 12 were included; 24 maternal blood samples were obtained together with 34 placental samples and 108 foetal organs. PFASs and cotinine were assayed by liquid chromatography/triple quadrupole mass spectrometry. RESULTS: In foetal organs, the average concentrations of perfluorooctanesulphonic acid (PFOS), perfluorooctanoic acid (PFOA), perfluorononanoic acid (PFNA), perfluoroundecanoic acid (PFUnDa), and perfluorodecanoic acid (PFDA) were 0.6ng/g, 0.2ng/g, 0.1ng/g, 0.1ng/g, and 0.1ng/g, respectively. A significant positive correlation was found between the exposure duration, defined as foetal age, and foetal to maternal ratio for all five PFASs and cotinine. Smokers presented 99ng/g cotinine in plasma, 108ng/g in placenta, and 61ng/g in foetal organs. No correlation between the maternal cotinine concentrations and PFAS concentrations was found. CONCLUSIONS: PFASs were transferred from mother to foetus, however, with different efficiencies. The concentrations of PFOS, PFOA, PFNA, PFUnDA, and PFDA in foetal organs were much lower than the maternal concentrations. Furthermore, a significant correlation between the exposure duration and all of the evaluated PFASs was found. The health-compromising concentrations of these substances during foetal development are unknown.

Acute respiratory effects and biomarkers of inflammation due to welding-derived nanoparticle aggregates.

PURPOSE: Welders are exposed to airborne particles from the welding environment and often develop symptoms work-related from the airways. A large fraction of the particles from welding are in the nano-size range. In this study we investigate if the welders' airways are affected by exposure to particles derived from gas metal arc welding in mild steel in levels corresponding to a normal welding day. METHOD: In an exposure chamber, 11 welders with and 10 welders without work-related symptoms from the lower airways and 11 non-welders without symptoms, were exposed to welding fumes (1 mg/m3) and to filtered air, respectively, in a double-blind manner. Symptoms from eyes and upper and lower airways and lung function were registered. Blood and nasal lavage (NL) were sampled before, immediately after and the morning after exposure for analysis of markers of oxidative stress. Exhaled breath condensate (EBC) for analysis of leukotriene B4 (LT-B4) was sampled before, during and immediately after exposure. RESULTS: No adverse effects of welding exposure were found regarding symptoms and lung function. However, EBC LT-B4 decreased significantly in all participants after welding exposure compared to filtered air. NL IL-6 increased immediately after exposure in the two non-symptomatic groups and blood neutrophils tended to increase in the symptomatic welder group. The morning after, neutrophils and serum IL-8 had decreased in all three groups after welding exposure. Remarkably, the symptomatic welder group had a tenfold higher level of EBC LT-B4 compared to the two groups without symptoms. CONCLUSION: Despite no clinical adverse effects at welding, changes in inflammatory markers may indicate subclinical effects even at exposure below the present Swedish threshold limit (8 h TWA respirable dust).

Female exposure to phthalates and time to pregnancy: a first pregnancy planner study.

STUDY QUESTION: Is female exposure to phthalate metabolites associated with reduced fecundity, as estimated by prolonged time to pregnancy (TTP)? SUMMARY ANSWER: Female exposure to monoethyl phthalate (MEP) but not monobutyl phthalate (MBP), monobenzyl phthalate (MBzP) and monoethylhexyl phthalate (MEHP) was associated with a longer TTP. WHAT IS KNOWN ALREADY: Male exposure to phthalates is potentially associated with adverse effects on human fecundity in epidemiological studies, but little is known about the potential effects on female reproduction. STUDY DESIGN SIZE AND DURATION: A cohort study with prospective data based on 229 women from a Danish cohort of 430 first pregnancy planning couples enrolled in 1992-1994. In 2009, urinary analyses of phthalate metabolites were performed on stored urine samples from this cohort. PARTICIPANTS/MATERIALS, SETTING AND METHODS: We analyzed MEP, MBP, MBzP and MEHP in female morning spot urine samples collected daily during the first 10 days of menstrual cycles after discontinuation of contraception. The exposure assessment was based on the mean of two measurements from each woman collected in a period of 6 menstrual cycles. We used Cox regression with discrete time to estimate fecundability ratios (FRs) and 95% CI in relation to the average urine metabolite concentration exposure level, controlled for age and BMI, and the time-varying variables smoking and alcohol. MAIN RESULT AND ROLE OF CHANCE: Urinary concentration of MEP was associated with a decreased fecundity (adjusted FR 0.79; 95% CI: 0.63; 0.99) corresponding to a 21% decreased probability of conception for each natural log (ln) unit increase in MEP. No significant association with TTP was found for MBP, MBzP and MEHP. LIMITATIONS REASONS FOR CAUTION: Subfertile women were overrepresented in the study population due to exclusion of 77 high fertile women who became pregnant in the first cycle when urine collection began. WIDER IMPLICATIONS OF THE FINDINGS: Our results suggest that female exposure to MEP may have an adverse effect on female fecundity, but these findings need to be replicated in a larger and newer cohort study with sufficient exposure contrast if the use of diethyl phthalate (DEP) and thereby MEP in the future potentially should be regulated in cosmetics and industrial consumer products. STUDY FUNDING/COMPETING INTERESTS: The original data collected were founded by Aarhus University Research Foundation, the Danish Medical Research Council and the Danish Medical Health Insurance Foundation. There are no conflicts of interest to be declared. TRIAL REGISTRATION NUMBER: N/A.

Diverging temporal trends of human exposure to bisphenols and plastizisers, such as phthalates, caused by substitution of legacy EDCs?

Phthalates and phenolic substances were investigated in urine samples from first-time mothers in Uppsala, Sweden, collected between 2009 and 2014. These substances have a comparably fast metabolism and urinary metabolites are predominantly analysed. The main aim was to investigate if measures to decrease production and use of certain phthalates and bisphenol A (BPA) have resulted in decreased human exposure, and to determine if exposures to replacement chemicals have increased. Temporal trends were evaluated for metabolites (n=13) of seven phthalates, a phthalate replacer, four different bisphenols, triclosan, one organophosphate-based flame retardant, and for two pesticides. The results showed downward trends of several phthalates which are in the process of being regulated and phased out. Concomitantly, an increasing trend was seen for a metabolite of the phthalate replacer Di-iso-nonylcyclohexane 1,2-dicarboxylate (DiNCH). Bisphenol A (BPA) showed a downward trend, whereas bisphenol F, identified as one of the substitutes for BPA, showed an increasing trend. The decreasing trend of triclosan is likely due to declining use within the EU. Temporal trend studies of urine samples make it possible to investigate human exposure to rapidly metabolised substances and study how measures taken to regulate and replace problematic chemicals affect human exposure.

Prenatal smoking exposure, measured as maternal serum cotinine, and children's motor developmental milestones and motor function: A follow-up study.

BACKGROUND: Cohort studies have indicated an association between prenatal smoking exposure and children's motor difficulties. However, results are inconsistent and exposure is most often self-reported. Studies indicate that measurement of serum cotinine can result in a more accurate status of smoking exposure in comparison with self-report. OBJECTIVES: To investigate whether prenatal smoking exposure, measured as maternal serum cotinine, is associated with maternal interview based assessment of motor development in infancy (age at crawling, standing-up and walking) and motor skills at young school age (assessed by the Developmental Coordination Disorder Questionnaire 2007 (DCDQ'07)). METHOD: In 2002-2004, 1,253 pregnant women from Greenland and Ukraine were included in the INUENDO birth cohort. The participating women filled in questionnaires and 1,177 provided blood samples, which were analyzed for serum cotinine. Smokers were defined as women with a serum cotinine concentration >10ng/ml. At follow-up when the offspring were 6-9 years of age 1,026 of the parents from the cohort participated. They completed an interview-based questionnaire including questions about age at motor milestones of their children. In addition, child motor development was assessed using the questionnaire "DCDQ'07". Linear regression analyzes were performed and adjusted for covariates; age of the mother and child, parity, sex, maternal educational level, maternal pre-pregnancy alcohol consumption and duration of breastfeeding. Data were stratified by country. RESULTS: No statistically significant difference in age at motor milestones was found comparing children of smokers with children of non-smokers. Also, there was no statistically significant difference in motor score (Developmental Coordination Disorder Questionnaire Score, DCDQ-score) among five to seven-year-old children. However, in Greenland children of smokers had a lower DCDQ-score than children of non-smokers at eight to nine years (-2.2 DCDQ points, 95% CI: -4.3;-0.1). Supplementary results for the same age group in Greenland showed that children of smokers had higher odds of being classified with motor difficulties in comparison with children of non-smokers (OR=1.9, 95% CI: 1.1;3.3). CONCLUSION: Maternal serum cotinine was not related to delayed motor development milestones or reduced motor function abilities in children up to 7 years of age. Reduced motor skills observed in 8-9 years old exposed children warrant further study.

Exposure to persistent organic pollutants and sperm DNA methylation changes in Arctic and European populations.

Persistent organic pollutants (POPs), such as PCBs (polychlorinated biphenyls) and DDT [1,1,1-trichloro-2,2-bis(4-chlorophenyl)ethane], are environmental contaminants with potential endocrine disrupting activity. DNA methylation levels in peripheral blood lymphocytes have been associated with serum concentrations of POPs in Greenland Inuit and Korean populations. Greenland Inuits are characterized by the highest worldwide POP levels. In this cross-sectional study we evaluated the relationship between serum POP concentrations and DNA methylation levels in sperm of non-occupationally exposed fertile men from Greenland, Warsaw (Poland), and Kharkiv (Ukraine). Serum levels of PCB-153 [1,2,4-trichloro-5-(2,4,5-trichlorophenyl)benzene], as a proxy of the total PCBs body burden, and of p,p'-DDE [1,1-dichloro-2,2-bis(4-chlorophenyl)ethylene], the main metabolite of DDT were measured. Sperm DNA methylation level was assessed globally by flow cytometric (FCM) immunodetection of 5-methyl-cytosines and at specific repetitive DNA sequences (Alu, LINE-1, Satα) by PCR-pyrosequencing after bisulfite conversion. Multivariate linear regression analysis was applied to investigate correlations between serum POP concentrations and DNA methylation. No consistent associations between exposure to POPs and sperm DNA methylation at repetitive DNA sequences were detected. A statistically significant global decrease in methylation was associated with exposure to either POP by FCM analysis. This is the first study to investigate environmental exposure to POPs and DNA methylation levels considering sperm as the target cells. Although POP exposure appears to have a limited negative impact on sperm DNA methylation levels in adult males, the global hypomethylation detected by one of the methods applied suggests that further investigation is warranted.

Cotinine Validation of Self-Reported Smoking During Pregnancy in the Swedish Medical Birth Register.

INTRODUCTION: Self-reported data on smoking during pregnancy from the Medical Birth Register of Sweden (MBR) are widely used. However, underreporting of such behavior may occur, leading to biases. It is of importance to validate the smoking data in the MBR. The main objective was to investigate the agreement between self-reported smoking data from the MBR and cotinine levels in maternal serum among women from the general population in the region of Skåne, Sweden. We also estimated the transfer of cotinine from mother to fetus. METHODS: From a cohort used previously to investigate the relationship between intrauterine environmental exposures and offspring neuropsychiatric outcomes, there were 204 control children retrieved from the MBR with data on maternal smoking in early pregnancy registered. Data on maternal and umbilical cord cotinine at delivery were available for these children from a regional biobank. RESULTS: There was a high agreement between cotinine levels and MBR smoking data (κ = 0.82) and a high correlation between cotinine levels in maternal and umbilical cord serum (r s = 0.90, P < .001). Of the self-reported nonsmokers, 95% (95% confidence interval: 89% to 97%) were classified as nonsmokers after cotinine measurements. CONCLUSION: In these data, we found that the agreement between mothers' self-reported smoking habits during pregnancy and their levels of serum cotinine was high, as was the transfer of cotinine from mother to fetus. This indicates that birth register data on pregnancy smoking in Sweden could be considered a valid measure.

Perfluorooctane Sulfonate Concentrations in Amniotic Fluid, Biomarkers of Fetal Leydig Cell Function, and Cryptorchidism and Hypospadias in Danish Boys (1980-1996).

BACKGROUND: Exposure to perfluorooctane sulfonate (PFOS) may potentially disturb fetal Leydig cell hormone production and male genital development. OBJECTIVES: We aimed to study the associations between levels of amniotic fluid PFOS, fetal steroid hormone, and insulin-like factor 3 (INSL3) and the prevalence of cryptorchidism and hypospadias. METHODS: Using the Danish National Patient Registry, we selected 270 cryptorchidism cases, 75 hypospadias cases, and 300 controls with stored maternal amniotic fluid samples available in a Danish pregnancy-screening biobank (1980-1996). We used mass spectrometry to measure PFOS in amniotic fluid from 645 persons and steroid hormones in samples from 545 persons. INSL3 was measured by immunoassay from 475 persons. Associations between PFOS concentration in amniotic fluid, hormone levels, and genital malformations were assessed by confounder-adjusted linear and logistic regression. RESULTS: The highest tertile of PFOS exposure (> 1.4 ng/mL) in amniotic fluid was associated with a 40% (95% CI: -69, -11%) lower INSL3 level and an 18% (95% CI: 7, 29%) higher testosterone level compared with the lowest tertile (< 0.8 ng/mL). Amniotic fluid PFOS concentration was not associated with cryptorchidism or hypospadias. CONCLUSIONS: Environmental PFOS exposure was associated with steroid hormone and INSL3 concentrations in amniotic fluid, but was not associated with cryptorchidism or hypospadias in our study population. Additional studies are needed to determine whether associations with fetal hormone levels may have long-term implications for reproductive health. CITATION: Toft G, Jönsson BA, Bonde JP, Nørgaard-Pedersen B, Hougaard DM, Cohen A, Lindh CH, Ivell R, Anand-Ivell R, Lindhard MS. 2016. Perfluorooctane sulfonate concentrations in amniotic fluid, biomarkers of fetal Leydig cell function, and cryptorchidism and hypospadias in Danish boys (1980-1996). Environ Health Perspect 124:151-156; http://dx.doi.org/10.1289/ehp.1409288.

Prenatal Phthalate, Perfluoroalkyl Acid, and Organochlorine Exposures and Term Birth Weight in Three Birth Cohorts: Multi-Pollutant Models Based on Elastic Net Regression.

BACKGROUND: Some legacy and emerging environmental contaminants are suspected risk factors for intrauterine growth restriction. However, the evidence is equivocal, in part due to difficulties in disentangling the effects of mixtures. OBJECTIVES: We assessed associations between multiple correlated biomarkers of environmental exposure and birth weight. METHODS: We evaluated a cohort of 1,250 term (≥ 37 weeks gestation) singleton infants, born to 513 mothers from Greenland, 180 from Poland, and 557 from Ukraine, who were recruited during antenatal care visits in 2002-2004. Secondary metabolites of diethylhexyl and diisononyl phthalates (DEHP, DiNP), eight perfluoroalkyl acids, and organochlorines (PCB-153 and p,p´-DDE) were quantifiable in 72-100% of maternal serum samples. We assessed associations between exposures and term birth weight, adjusting for co-exposures and covariates, including prepregnancy body mass index. To identify independent associations, we applied the elastic net penalty to linear regression models. RESULTS: Two phthalate metabolites (MEHHP, MOiNP), perfluorooctanoic acid (PFOA), and p,p´-DDE were most consistently predictive of term birth weight based on elastic net penalty regression. In an adjusted, unpenalized regression model of the four exposures, 2-SD increases in natural log-transformed MEHHP, PFOA, and p,p´-DDE were associated with lower birth weight: -87 g (95% CI: -137, -340 per 1.70 ng/mL), -43 g (95% CI: -108, 23 per 1.18 ng/mL), and -135 g (95% CI: -192, -78 per 1.82 ng/g lipid), respectively; and MOiNP was associated with higher birth weight (46 g; 95% CI: -5, 97 per 2.22 ng/mL). CONCLUSIONS: This study suggests that several of the environmental contaminants, belonging to three chemical classes, may be independently associated with impaired fetal growth. These results warrant follow-up in other cohorts.

Analysis of nanoparticle-protein coronas formed in vitro between nanosized welding particles and nasal lavage proteins.

Welding fumes include agglomerated particles built up of primary nanoparticles. Particles inhaled through the nose will to some extent be deposited in the protein-rich nasal mucosa, and a protein corona will be formed around the particles. The aim was to identify the protein corona formed between nasal lavage proteins and four types of particles with different parameters. Two of the particles were formed and collected during welding and two were manufactured iron oxides. When nasal lavage proteins were added to the particles, differences were observed in the sizes of the aggregates that were formed. Measurements showed that the amount of protein bound to particles correlated with the relative size increase of the aggregates, suggesting that the surface area was associated with the binding capacity. However, differences in aggregate sizes were detected when nasal proteins were added to UFWF and Fe2O3 particles (having similar agglomerated size) suggesting that yet parameters other than size determine the binding. Relative quantitative mass spectrometric and gel-based analyses showed differences in the protein content of the coronas. High-affinity proteins were further assessed for network interactions. Additional experiments showed that the inhibitory function of secretory leukocyte peptidase inhibitor, a highly abundant nasal protein, was influenced by particle binding suggesting that an understanding of protein function following particle binding is necessary to properly evaluate pathophysiological events. Our results underscore the importance of including particles collected from real working environments when studying the toxic effects of particles because these effects might be mediated by the protein corona.

Vitamin D Status at Birth and Future Risk of Attention Deficit/Hyperactivity Disorder (ADHD).

OBJECTIVE: To investigate whether children with Attention Deficit/Hyperactivity Disorder have lower levels of Vitamin D3 at birth than matched controls. MATERIAL: Umbilical cord blood samples collected at birth from 202 children later diagnosed with Attention Deficit/Hyperactivity Disorder were analysed for vitamin D content and compared with 202 matched controls. 25-OH vitamin D3 was analysed by liquid chromatography tandem mass spectrometry. RESULTS: No differences in cord blood vitamin D concentration were found between children with Attention Deficit/Hyperactivity Disorder (median 13.0 ng/ml) and controls (median 13.5 ng/ml) (p = 0.43). In a logistic regression analysis, Attention Deficit/Hyperactivity Disorder showed a significant association with maternal age (odds ratio: 0.96, 95% confidence interval: 0.92-0.99) but not with vitamin D levels (odds ratio: 0.99, 95% confidence interval: 0.97-1.02). CONCLUSION: We found no difference in intrauterine vitamin D levels between children later developing Attention Deficit/Hyperactivity Disorder and matched control children. However, the statistical power of the study was too weak to detect an eventual small to medium size association between vitamin D levels and Attention Deficit/Hyperactivity Disorder.

LC-MS-MS Analysis of Urinary Biomarkers of Imazalil Following Experimental Exposures.

Imazalil (IMZ) is a fungicide used in the cultivation of vegetables, such as cucumbers, in green houses or post-harvest on fruit to avoid spoilage due to fungal growth. Agricultural workers can be occupationally exposed to IMZ and the general public indirectly by the diet. The purpose of this study was to develop and validate an LC-MS-MS method for the analysis of IMZ in human urine. The method used electrospray ionization and selected reaction monitoring in the positive mode. Excellent linearity was observed in the range 0.5-100 ng/mL. The limit of detection of the method was 0.2 ng/mL, and the limit of quantitation 0.8 ng/mL. The method showed good within-run, between-run and between-batch precision, with a coefficient of variation <15%. The method was applied to analyze urine samples obtained from two human volunteers following experimental oral and dermal exposure. The excretion of IMZ seemed to follow a two-compartment model and first-order kinetics. In the oral exposure, the elimination half-life of IMZ in the rapid excretion phase was 2.6 and 1.9 h for the female and the male volunteer, respectively. In the slower excretion phase, it was 7.6 and 13 h, respectively. In the dermal exposure, the excretion seemed to follow a single-compartment model and first-order kinetics. The elimination half-life was 10 and 6.6 h for the female and the male volunteer, respectively. Although the study is limited to two volunteers, some information on basic toxicokinetics and metabolism of IMZ in humans is presented.

Phthalate exposure and reproductive parameters in young men from the general Swedish population.

BACKGROUND: In animals, exposure to certain phthalates negatively affects the male reproductive function. Human results are conflicting and mostly based on subfertile males, in whom the association between exposure and reproductive function may differ from the general population. OBJECTIVES: To study if levels of phthalate metabolites were associated with semen quality and reproductive hormones in general Swedish men. METHODS: We recruited 314 young men delivering semen, urine and blood samples at the same visit. We analyzed reproductive hormones and several semen parameters including progressive motility and high DNA stainability (HDS)-a marker for sperm immaturity. In urine, we analyzed metabolites of phthalates, including diethylhexyl phthalate (DEHP). We studied associations between urinary levels of the metabolites and seminal as well as serum reproductive parameters, accounting for potential confounders. RESULTS: DEHP metabolite levels, particularly urinary mono-(2-ethyl-5-carboxypentyl) phthalate (MECPP), were negatively associated with progressive sperm motility, which was 11 (95% CI: 5.0-17) percentage points lower in the highest quartile of MECPP than in the lowest. Further, men in the highest quartile of the DEHP metabolite monoethylhexyl phthalate had 27% (95% CI: 5.5%-53%) higher HDS than men in the lowest quartile. CONCLUSIONS: DEHP metabolite levels seemed negatively associated with sperm motility and maturation.

Levels of perfluoroalkyl substances and risk of coronary heart disease: Findings from a population-based longitudinal study.

BACKGROUND: Cross-sectional studies have shown an association between exposure to perfluoroalkyl substances (PFASs) and coronary heart disease (CHD). These findings need to be evaluated in longitudinal settings. OBJECTIVES: To investigate the risk of CHD in relation to PFAS levels in a longitudinal setting among Swedish rural residents. METHODS: In a population-based prospective cohort of male farmers and rural residents recruited in 1990-1991, all men who received a CHD diagnosis between 1992 and 2009 were identified from national registers (n=253). For each CHD case, one control, matched for age, was chosen randomly from the cohort. For all cases and controls, levels of eight PFASs at baseline were measured in stored blood samples. In addition, for a subsample, PFAS levels were also measured in serum samples collected at a follow-up in 2002-2003. RESULTS: There were no statistically significant associations between levels of seven of the eight PFASs at baseline and risk for developing CHD. There was a significant association between perfluoroheptanoic acid (PFHpA) and CHD (OR=2.72; 95% CI: 1.52, 4.84) for the 3rd quartile and (OR=2.45; 95% CI: 1.40, 4.29) for the 4th quartile compared to the lowest quartile. Changes in levels of PFCs between baseline and follow-up did not differ systematically between cases and controls. CONCLUSIONS: This longitudinal study does not lend support to the previously reported cross-sectional relationship between PFAS levels and CHD risk. We found a significant association with PFHpA, but this could be a chance finding, considering its chemical resemblance to other PFASs.