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Background: Evaluation of male fertility includes standard semen analysis; however, there is uncertainty about the value of sperm parameters in predicting fertility. Objective: To evaluate the association between semen parameters and fatherhood during a long‐time period. Materials and methods: Semen parameters (total sperm count, concentration, motility, and morphology) and sperm DNA fragmentation Index (DFI) assessed on samples collected from 195 Norwegian men from the general population in 2001/2002 were matched with information about fatherhood until 2015, obtained from the Medical Birth Register. The parameters were dichotomized as normal vs. abnormal according to the WHO reference values from 1999 and 2010. Cut‐offs at 20% and 30% were used for DFI. Results: Among men who had no children before 2003, those with normal progressive sperm motility had more often become fathers (WHO 1999, cut‐off ≥50%, adjusted OR 2.8, 95% CI 1.3–6.1 and WHO 2010, cut‐off ≥32%; aOR 4.2, 95% CI 1.1–15). Based on the WHO 1999 reference value, men with normal sperm concentration (≥20 × 106/mL) had more often become fathers (aOR 3.1, 95% CI 1.1–8.6). Men with progressive sperm motility ≥50% and concentration ≥20 × 106/mL did more often achieve fatherhood (aOR 8.4, 95% CI 2.1–34). For DFI, there was a borderline significance at cut‐off 20% in the group of men who had ever been fathers (OR 2.7, 95% CI 1.0–7.0 p < 0.05). Discussion: The results indicate that sperm progressive motility, sperm concentration, and DFI are associated with fatherhood during a longer time period, with sperm motility being most consistent. Although the sample size is relatively small and our results should be replicated in larger studies, they may be of clinical relevance. Conclusion: Semen parameters may have a diagnostic value not only in a short time frame but also for predicting future fertility potential. [ABSTRACT FROM AUTHOR]

Highlights: • The dogma that AR activity is linearly related to AR CAG length has been challenged. • Only 2 out of 21 reproductive makers are linearly related to AR CAG/GGN length. • Majority of reproductive markers are non-linearly associated with CAG/GGN length. • Non-linear associations are confirmed using flexible spline regression models. [Copyright &y& Elsevier]

INTRODUCTION Based on historical data, a decline in sperm counts during the years 1940–1990 has been suggested and aetiologically linked to a concomitant increase in the incidence of testicular cancer. This study, focusing on possible changes in sperm parameters among young Swedish men, during the past 10 years, was specifically designed in order to answer the question of whether there is a continuing decline in sperm counts. METHODS During the period 2008–2010, 295 young (17–20 years; median 18) men born and raised in Sweden were recruited at the age they were supposed to undergo medical examination prior to military service. The participants filled in questionnaires, underwent andrological examination and delivered an ejaculate. Their semen parameters were compared with those of a similar cohort of men (n = 216) recruited in the year 2000–2001. RESULTS No significant changes (means; 2000–2001 versus 2008–2010) in sperm concentration (78 × 106/ml versus 82 × 106/ml; P = 0.54), semen volume (3.1 ml versus 3.0 ml; P = 0.26) or total sperm counts (220 × 106 versus 250 × 106; P = 0.18) were found. The proportion of progressively motile spermatozoa also remained unchanged. CONCLUSIONS Between the years 2000 and 2010 we found no evidence of time-related deterioration of semen parameters among young Swedish men from the general population. This finding does not exclude that such a decrease may have taken place before year 2000. If the risk of testicular cancer is linked to the sperm counts, the increase in incidence of this malignancy should be levelling off in southern Sweden in the next 10–15 years. [ABSTRACT FROM PUBLISHER]

Background Foreign-born workers in high-income countries experience higher rates of COVID-19 but the causes are only partially known. Aims To examine if the occupational risk of COVID-19 in foreign-born workers deviates from the risk in native-born employees in Denmark. Methods Within a registry-based cohort of all residents employed in Denmark (n = 2 451 542), we identified four-digit DISCO-08 occupations associated with an increased incidence of COVID-19-related hospital admission during 2020–21 (at-risk occupations). The sex-specific prevalence of at-risk employment in foreign born was compared with the prevalence in native born. Moreover, we examined if the country of birth modified the risk of a positive SARS-CoV-2 polymerase chain reaction (PCR) test and COVID-19-related hospital admission in at-risk occupations. Results Workers born in low-income countries and male workers from Eastern Europe more often worked in at-risk occupations (relative risks between 1.16 [95% confidence interval {CI} 1.14–1.17] and 1.87 [95% CI 1.82–1.90]). Being foreign-born modified the adjusted risk of PCR test positivity (test for interaction P < 0.0001), primarily because of higher risk in at-risk occupations among men born in Eastern European countries (incidence rate ratio [IRR] 2.39 [95% CI 2.09–2.72] versus IRR 1.19 [95% CI 1.14–1.23] in native-born men). For COVID-19-related hospital admission, no overall interaction was seen, and in women, country of birth did not consistently modify the occupational risk. Conclusions Workplace viral transmission may contribute to an excess risk of COVID-19 in male workers born in Eastern Europe, but most foreign-born employees in at-risk occupations seem not to be at higher occupational risk than native born. [ABSTRACT FROM AUTHOR]

Cohorts comprising fishermen's families on the east coast of Sweden have been found to have a high consumption of contaminated fish as well as high body burdens of persistent organochlorine pollutants (POPs). Their west coast correspondents are socio-economically similar, but with considerably lower POP exposure since the fish caught on the west coast is far less contaminated. The rationale for this was that the cohorts residing on the east coast of Sweden have been found to have a high consumption of contaminated fish as well as high body burdens of POPs, whereas their west coast correspondents are socio-economically similar, but with considerably lower POP exposure since the fish caught on the west coast is far less contaminated. Among the reproductive outcomes investigated are included both male and female parameters, as well as couple fertility and effects on the fetus. A range of exposure measures, including both questionnaire assessments of fish consumption and biomarkers, have been used. The most consistent findings of the studies are those related to the fetus, where a decreased birth weight was found across all measures of exposure, which is in agreement with studies from other populations. Some markers for male reproduction function, i.e. sperm motility, sperm chromatin integrity, and Y:X chromosome ratio, were associated with POP exposure, whereas others, such as sperm concentration and semen volume, were not. With respect to couple fertility and female reproductive parameters, no support was given for associations with POP exposure. Although some associations may have been affected by beneficial effects of essential nutrients in seafood, the overall findings are meaningful in the context of reproductive toxicity and support the usefulness of the epidemiological design. [ABSTRACT FROM AUTHOR]

OBJECTIVE: We synthesized the main findings from an international epidemiologic study on the impact of biopersistent organic pollutants (POPs) on human reproductive function. DATA SOURCES AND EXTRACTION: We used a database with interview and biological data from 2,269 women and their spouses, and 18 published core papers. DATA SYNTHESIS: The study did not provide direct evidence of hormone-like activity of the polychlorinated biphenyl (PCB) congener CB-153 and the main dichlorodiphenyltrichloroethane (DDT) metabolite, 1,1-dichloro-2,2-bis(p-chlorophenyl)ethylene (p,p'-DDE), as serum concentrations of these compounds were not consistently related to either endogenous or exogenous hormone activity in serum. Nevertheless several links bewteen POP exposure and biomarkers of male reproductive function were identified. First, an association between high CB-153 serum levels and low sperm counts was detected within a subgroup of men with short androgen receptor CAG repeat length. Second, a relationship between increased CB-153 serum concentrations and decreased sperm motility was seen in all four studied regions, and indications of reduced neutral alpha-glucosidase activity in seminal plasma point to a post-testicular effect. Third, damage of sperm chromatin integrity was considerably less frequent in Greenlandic Inuits compared with that in European groups, and only in the latter was impairment of sperm chromatin integrity related to POPs. Despite these effects, fertility in terms of time taken to conceive was not related to POPs except in Inuits. A likely explanation of the latter was not identified. CONCLUSIONS: POPs may interfere with male reproductive function without major impact on fertility. The data do not provide direct evidence for endocrine disruption, hence other mechanisms should also be considered. [ABSTRACT FROM AUTHOR]

To ascertain the frequency of treatment-related acute myeloid leukemias and myelodysplastic syndromes (t-AML/t-MDS) in an unselected series, we have identified all adult cases analyzed in our department from 1976 to 1993. Further aims were to compare karyotypic features of t-AML/t-MDS with de novo AML/MDS, in our material as well as in 5098 unselected, cyto- genetically abnormal, published cases, and to analyze associations between type of prior therapy and karyotype. Among our 372 AML and 389 MDS, 47 (13%) were t-AML and 62 (16%) were t-MDS. Clonal abnormalities were significantly more common in t-AML and t-MDS than in de novo disease (68% vs 50%, P < 0.05 and 84% vs 45%, P < 0.001, respectively). Among the available 4230 AML and 1629 MDS (the present series and published cases), 14% were t-AML and 15% were t-MDS. In t-AML/t-MDS, the number of anomalies and the ploidy levels differed significantly from de novo cases, with complex and hypodiploid karyotypes being more common in t-AML/t-MDS. In t-AML, unbalanced changes in general, t(1;3), der(1;7), 3p-, -5, 5q-, -7, 7q-, t(9;11), t(11;19), t(11q23), der(12p), -17, der(17p), -18, and -21 were significantly more frequent than in de novo AML. In t-MDS, -5, -7, 7q-, 13q-, der(17p), and -18 were significantly more common. Type of prior treatment correlated significantly with number of anomalies in t-AML and with ploidy levels in t-AML/t-MDS. The frequencies of several aberrations varied with type of therapy, eg, 5q- was more frequent in radiotherapy-associated t-MDS, monosomy 7 was more common in t-AML and t-MDS after treatment with alkylators, and t(11q23) in t-AML was associated with topoisomerase II inhibitors. Abnormalities significantly more common in de novo disease were +8 as a sole anomaly, balanced changes in general, t(8;21), t(9;22), t(15;17), inv(16), and t(21q22) in AML, and -Y, 5q-, and 20q- as sole anomalies and +8 in MDS. The results emphasize the strong association between previous genotoxic... [ABSTRACT FROM AUTHOR]

Background: The exposure–response relationships for the induction of specific IgE and IgG were evaluated in a prospective study of workers exposed to organic acid anhydrides (OAAs). Special attention was paid to the modifying effects of atopy and smoking. Methods: The subjects were 163 previously unexposed persons exposed to epoxy resins with hexahydro-, methylhexahydro-, and methyltetrahydrophthalic anhydride as curing agents. The levels of OAAs in air and of specific IgE and IgG in serum were recurrently monitored. The mean observation time was 32 (1–105) months. Results: The mean combined OAA exposure of the subjects was 15.4 (<1–189) μg/m3. Positive specific IgE was demonstrated by 21 (13%) subjects with a mean induction time of 8.8 (1–35) months. The incidence of sensitization was 4.1 cases/1000 months at risk. The relative risk (OR) for atopics was 5.4 (1.9-15.3; 95% CI). An exposure–response relationship was demonstrated by an increasing risk of sensitization with increasing exposure. Conclusions: An association between exposure and atopy, respectively, and the induction of specific antibodies against OAAs were observed. The risk for atopics was comparable with the risk for the subjects in the most exposed group. [ABSTRACT FROM AUTHOR]

The prognostic impact of karyotypic patterns in a consecutive series of 389 adult myelodysplastic syndromes (MDS) was investigated. Time period did not significantly influence the survival times. In the analyses, the MDS cases were subdivided into the cytogenetic subgroups used in the International Prognostic Scoring System, i.e. favourable [–Y, del(5q) or del(20q) as single aberrations or normal karyotype, n = 241], poor [-7, del(7q), der(1;7) or complex karyotypes, i.e. ≥ three abnormalities, n = 89] and intermediate (other aberrations, n = 59). The survival times correlated well with the prognostic subgroups, confirming that the cytogenetic classification was valid. Expressed as hazard ratios (HRs), with the favourable subgroup as the reference, the intermediate and poor subgroup HRs increased to 1·5 (95% confidence interval, 1·1–2·1) and 3·2 (2·4–4·1) respectively. Sex, age, morphological subtype and smoking habits significantly modified this prognostic impact. Shorter survival was detected for men in the favourable and the intermediate subgroups, but not in the poor prognosis subgroup. Using women in the favourable subgroup as the reference and adjusting for age, the HR for men was 1·6 (1·2–2·1) in the favourable subgroup. Adjusting for smoking habits as well decreased the HR to 1·4 (1·1–2·0) and, when also excluding cases with del(5q) as the sole anomaly, no significant difference could be discerned [HR 1·2 (0·9–1·6], suggesting that the better outcome for women in the favourable subgroup was mainly as a result of the ‘5q-syndrome’ and to smoking habits. In the intermediate subgroup, the corresponding HRs were 3·0 (1·5–6·0) when adjusted for age and 2·7 (1·3–5·5) when also adjusted for smoking habits. Different survival times between men and women have never previously been reported for this MDS group. Although it remains to be elucidated whether environmental and/or constitutional factors cause the observed sex-related difference, these observations have obvious clinical ramifications, not least in designing and evaluating therapy protocols. [ABSTRACT FROM AUTHOR]

Context: Patients with craniopharyngioma (CP) and hypothalamic lesions (HL) have cognitive defcits. Which neural pathways are affected is unknown. Objective: To determine whether there is a relationship between microstructural white matter (WM) alterations detected with diffusion tensor imaging (DTI) and cognition in adults with childhood-onset CP. Design: A cross-sectional study with a median follow-up time of 22 (6-49) years after operation. Setting: The South Medical Region of Sweden (2.5 million inhabitants). Participants: Included were 41 patients (24 women, ≥17 years) surgically treated for childhood-onset CP between 1958-2010 and 32 controls with similar age and gender distributions. HL was found in 23 patients. Main outcome measures: Subjects performed cognitive tests and magnetic resonance imaging, and images were analyzed using DTI of uncinate fasciculus, fornix, cingulum, hippocampus and hypothalamus as well as hippocampal volumetry. Results: Right uncinate fasciculus was signifcantly altered (P ≤ 0.01). Microstructural WM alterations in left ventral cingulum were signifcantly associated with worse performance in visual episodic memory, explaining approximately 50% of the variation. Alterations in dorsal cingulum were associated with worse performance in immediate, delayed recall and recognition, explaining 26-38% of the variation, and with visuospatial ability and executive function, explaining 19-29%. Patients who had smaller hippocampal volume had worse general knowledge (P = 0.028), and microstructural WM alterations in hippocampus were associated with a decline in general knowledge and episodic visual memory. Conclusions: A structure to function relationship is suggested between microstructural WM alterations in cingulum and in hippocampus with cognitive defcits in CP. [ABSTRACT FROM AUTHOR]

Ground level ozone [ozone] is considered a harmful air pollutant but there is a knowledge gap regarding its long term health effects. The main aim of this study is to develop local Land Use Regression [LUR] models that can be used to study long term health effects of ozone. The specific aim is to develop spatial LUR models for two Swedish cities, Umeå and Malmö, as well as a temporal model for Malmö in order to assess ozone exposure for long term epidemiological studies. For the spatial model we measured ozone, using Ogawa passive samplers, as weekly averages at 40 sites in each study area, during three seasons. This data was then inserted in the LUR-model with data on traffic, land use, population density and altitude to develop explanatory models of ozone variation. To develop the temporal model for Malmö, hourly ozone data was aggregated into daily means for two measurement stations in Malmö and one in a rural area outside Malmö. Using regression analyses we inserted meteorological variables into different temporal models and the one that performed best for all three stations was chosen. For Malmö the LUR-model had an adjusted model R² of 0.40 and cross validation R² of 0.17. For Umeå the model had an adjusted model R² of 0.67 and cross validation adjusted R² of 0.48. When restricting the model to only including measuring sites from urban areas, the Malmö model had adjusted model R² of 0.51 (cross validation adjusted R² 0.33) and the Umeå model had adjusted model R² of 0.81 (validation adjusted R² of 0.73). The temporal model had adjusted model R² 0.54 and 0.61 for the two Malmö sites, the cross validation adjusted R² was 0.42. In conclusion, we can with moderate accuracy, at least for Umeå, predict the spatial variability, and in Malmö the temporal variability in ozone variation. [ABSTRACT FROM AUTHOR]

BACKGROUND Perfluorinated compounds (PFCs) have been suspected to adversely affect human reproductive health. The aim of this study was to investigate the associations between PFC exposure and male semen quality. METHODS PFCs were measured in serum from 588 partners of pregnant women from Greenland, Poland and Ukraine who provided a semen sample, using liquid chromatography tandem mass spectrometry. Perfluorooctane sulfonate (PFOS), perfluorooctanoic acid (PFOA), perfluorohexane sulfonic acid (PFHxS) and perfluorononanoic acid (PFNA) could be detected in >97% of the samples. The associations between levels of these compounds and semen volume, sperm concentration, total sperm count, motility and morphology were assessed. RESULTS Across countries, sperm concentration, total sperm count and semen volume were not consistently associated with PFOS, PFOA, PFHxS or PFNA levels. The proportion of morphologically normal cells was 35% lower [95% confidence interval (CI): 4–66%) for the third tertile of PFOS exposure as compared with the first. A similar reduction was found in relation to increasing PFHxS levels. At the third PFOA exposure tertile, the percentage of motile spermatozoa was 19% (95% CI: 1 to 39%) higher than in the first. CONCLUSIONS The most robust finding in the present study was the negative associations between PFOS exposure and sperm morphology suggesting adverse effects of PFOS on semen quality, possibly due to interference with the endocrine activity or sperm membrane function. It cannot be excluded that this association and the positive association between PFOA and semen motility, which was not consistent across countries, might represent a chance finding due to the multiple statistical tests being performed. [ABSTRACT FROM AUTHOR]

Background: Organic acid anhydrides (OAA) are used as hardeners in epoxy resin systems. They are powerful sensitizers giving frequent rhinitis and asthma in exposed workers. Incidence of symptoms is unknown. Here we present the first prospective study on the associations between OAA exposure, symptoms, and effects of confounding factors. Methods: All new employees in three plants handling OAA were followed for up to 8.5 years. Before the employment, a questionnaire reporting about symptoms of eyes and airways, smoking habits, and atopy was answered. The subjects were asked at regular medical examinations about work tasks and work-related symptoms. Serum was analysed for specific OAA antibodies. Results: Mean exposures varied between 6 and 39 μg/m3. The incidence for work-related symptoms of the eyes, nose, pharynx, and lower airways was 91, 64, 46, and 31 per 1000 years of exposure, respectively. Symptoms were found frequently, even at mean exposure level at <10 μg/m3. Smoking and atopy increased the risk of symptoms. Immunoglobulin (Ig)E sensitized workers had a significant increased risk for symptoms of the eyes and pharynx and for running nose/sneezing. Conclusions: Organic acid anhydrides exposure is associated with frequent ocular and airway symptoms even at mean exposure levels at <10 μg/m3. There is an important need for establishment of an occupational threshold limit. A limit value of below 5 μg/m3 is proposed. [ABSTRACT FROM AUTHOR]

Objective: Recent studies indicate that persistent organohalogen pollutants (POPs) may contribute to sex ratio changes in offspring of exposed populations. Our aim in the present study was to investigate whether exposure to 2,2 ,4,4 ,5,5 -hexachlorobiphenyl (PCB-153) and dichlorodiphenyldichloroethene (p,p -DDE) affects sperm Y:X chromosome distribution. Subjects and methods: We obtained semen and blood for analysis of PCB-153 and p,p -DDE levels from 547 men from Sweden, Greenland, Poland (Warsaw), and Ukraine (Kharkiv), with regionally different levels of POP exposure. The proportion of Y- and X-chromosome-bearing sperm in the semen samples was determined by two-color fluorescence in situ hybridization analysis. Results: Swedish and Greenlandic men had on average significantly higher proportions of Y sperm (in both cohorts, 51.2%) and correspondingly higher lipid-adjusted concentrations of PCB-153 (260 ng/g and 350 ng/g, respectively) compared with men from Warsaw (50.3% and 22 ng/g) and Kharkiv (50.7% and 54 ng/g). In the Swedish cohort, log-transformed PCB-153 and log-transformed p,p -DDE variables were significantly positively associated with Y-chromosome fractions (p-values 0.04 and < 0.001, respectively). On the contrary, in the Polish cohort PCB-153 correlated negatively with the proportion of Y-bearing fraction of spermatozoa (p = 0.008). Conclusions: The present study indicates that POP exposure might be involved in changing the proportion of ejaculated Y-bearing spermatozoa in human populations. Intercountry differences, with different exposure situations and doses, may contribute to varying Y:X chromosome ratios. Key words: polychlorinated biphenyls, POP, p, p -DDE, sex chromosomes, sex ratio, sperm. [ABSTRACT FROM AUTHOR]

Abstract: Relatively little is known about the cytogenetic features of multiple myeloma (MM) when compared to other hematologic malignancies. The reasons for this are most likely manifold, and include a low mitotic index of the malignant cells and the presence of cytogenetically cryptic abnormalities as well as of complex karyotypes with poor chromosome morphology. In the present study, we have investigated whether various culture conditions may influence the yield of abnormal metaphases in MM and, in the related plasma cell dyscrasias, monoclonal gammopathy of undetermined significance (MGUS) and plasmacytomas (PC). In addition, the possible impact of age, gender, and disease phase on the cytogenetic features has been analyzed. A total of 95 samples from 74 cases (68 MM, three PC, and three MGUS patients) were obtained for cytogenetic analysis. The samples were cultured either in conventional medium or in medium containing IL-6 and GM-CSF, and the culture times varied from 24 to 120 h. In total, 186 cultures were analyzed. Metaphase fluorescence in situ hybridization analysis using probes specific for 14q32, i.e. IGH rearrangements, could be performed in 57 of the 74 cases, and revealed 14q32 aberrations in 10 cases not seen by conventional G-banding. Abnormal karyotypes were detected in 77 (41%) of the 186 cultures, 46 (48%) of the 95 samples, and in 41 (55%) of the 74 patients, revealing a total of 20 chromosomal aberrations previously not reported in plasma cell dyscrasias. We found no evidence that gender, age, disease phase, culture time, or cytokine stimulation significantly influences the karyotypic features of MM. [ABSTRACT FROM AUTHOR]

Physical workload [muscular load of the trapezius and infraspinatus muscles using electromyography (EMG), wrist positions and movements by electrogoniometers] and neck and upper limb disorders (from, for example, a physical examination) were studied in women with repetitive industrial work (n = 95) and referents (n = 74). The repetitive work displayed higher ratings for wrist movements, but not for EMG. The prevalences of neck, shoulder and wrist/hand disorders were elevated for women with repetitive work [age-adjusted prevalence odds ratios (PORs) 2.0-7.5]. For the left hand, high frequency of wrist movements (mean power frequency 0.53 Hz) was associated with a high prevalence of disorders (56%), as compared to low (0.28 Hz and 26%; POR 3.5). We found no consistent and significant effect of muscular load, on either neck or shoulder disorders. However, selection and other bias may have diminished our possibility to observe such effects. Psychosocial work environment factors were not confounding the results. Measurements of wrist movements may be used for identification of high-risk work tasks. [ABSTRACT FROM AUTHOR]

A consecutive population-based series of 372 adult acute myeloid leukemias, successfully cytogenetically investigated at a single center between 1976 and 1993, is reported. All medical records were reviewed in order to ascertain the prognostic impact of karyotype, divided into three groups; favorable (t(8;21), t(15;17), and inv(16) irrespective of karyotypic complexity; n = 40), poor (der(1;7), inv(3), -5, del(5q), -7, t(9;22), and complex karyotypes including whole or partial losses of chromosomes 5 and/or 7; n = 56), and intermediate (other abnormalities or normal karyotype; n = 276). The possible modification by age, gender, time period, morphologic subtype, and bone marrow transplantation (BMT) on this prognostic impact was also determined. The chemotherapy regimens used were heterogeneous over time but principally the same at any given point in time. The majority of the patients were treated with combinations including an anthracycline and cytarabine with curative intent. Gender, morphology, and BMT did not significantly modify the effect of cytogenetic patterns on survival time, whereas age and time period did. The hazard ratios for the subgroups favorable, intermediate, and poor were 1.0, 1.2 and 1.9 at age 20-49; 1.0, 2.5 and 4.5 at age 50-64; 1.0, 4.1 and 11.4 at age 65-74; 1.0, 1.4 and 2.2 for the time period 1976-1987 and 1.0, 2.0 and 6.7 for 1988-1993. The salient feature of the Kaplan-Meier curves was the improved survival during the later time period for patients with favorable and intermediate cytogenetic abnormalities. The present findings thus suggest that it is mainly these patient groups that have benefited from advances in therapy, including supportive care. [ABSTRACT FROM AUTHOR]

Determination of the host polymorphism in the CYP1A1, GSTM1 and NAT2 genes was assessed by the PCR technique in 149 pipe-layers (cross-sectional study). The pipe-layers were exposed to pyrolysis products from polyurethane foam based on MDI, and to welding fumes. Respiratory symptoms, smoking history, and life-time em ployment history were obtained from a detailed questionnaire. A standard skin prick test was used to assess atopy.VC and FEV 1 were also determined. The proportion of men with irritative symptoms from the eyes, nose, and throat, and symptoms from the lower airways did not differ significantly between the subgroups of individuals divided according to biotransformation genotype. Further, we did not observe any differences between the subgroups for either VC, or FEV 1. The results were similar when age, atropy, smoking habits, and exposure was controlled for by logistic or linear regression modelling. [ABSTRACT FROM AUTHOR]

More women in reproductive ages are entering occupations where exposure to whole body vibrations (WBV) is common (e.g. in transportation and construction). Previous studies based on self-assessed exposure suggest increased risks of adverse birth outcomes, but it is unclear at what exposure levels and if the current exposure guidelines are appropriate during pregnancy. To investigate whether occupational WBV-exposure increases the risk of preterm birth, low birth weight, and/or small-for-gestational age, in a large, nationwide, prospective, cohort study. The Fetal Air Pollution Exposure cohort (FAIR) was formed by merging data from multiple, national registers, and the present study includes singletons born 1994–2014 to working women in Sweden (n = 1,091,080 births). WBV-exposure was assessed quantitatively using a job-exposure matrix based on measurements, and calculated odds ratios were adjusted for potential confounders such as smoking and BMI, and other occupational exposures like noise, combustion particles, and physically and psychologically strenuous work. Data on absence from work (full-/part time, sick leave, parental leave, etc.) was also used. Exposure to WBV during pregnancy, among women with low absence from work (n = 476,419), was associated with an increased risk of preterm birth, below the occupational exposure limit (1.15 m/s2). Compared to unexposed mothers, the OR was 1.38 (95% CI: 1.05, 1.83) for exposure ≥0.5 m/s2, corresponding to an increase from 47/1000 cases to 65/1000 cases. No increased risk was found for small-for-gestational age. Exposure to WBV was associated with an increased risk of preterm birth. The results suggest that the current permissible exposure and action levels for WBV-exposure do not adequately protect pregnant women with continuous exposure. Unlabelled Image • Risks of occupational exposure to whole body vibrations in pregnancy were assessed. • The study was a nationwide, register-based, cohort study in Sweden (n = 1,091,080). • Moderately high exposure was associated with an increased risk of preterm birth. • The increased risk was found among full-time workers with low absence from work. • The associations were present below the current exposure limit set by the EU. [ABSTRACT FROM AUTHOR]

Background: Epidemiological studies on the association between maternal exposure to persistent organic pollutants (POPs) and fetal growth alteration report inconsistent findings which weights in favor of additional studies.Methods: Blood samples were collected from interviewed pregnant women in Greenland (572), Kharkiv (611) and Warsaw (258) and were analyzed for CB-153 and p,p'-DDE by gas chromatography-mass spectrometry. Data on birth weight, gestational age and preterm birth were obtained for 1322 singleton live births. We examined the association between natural log-transformed serum POPs concentration and birth weight and gestational age using multiple linear regression and the association with prematurity using logistic regression controlling for potential confounding factors.Results: The median serum concentrations of CB-153 and p,p'-DDE were for Inuit mothers 105.6 and 298.9, for Kharkiv mothers 27.0 and 645.4 and for Warsaw mothers 10.7 and 365.2 ng/g lipids, respectively. Increase in CB-153 concentration by one unit on the log scale in Inuit mothers serum was associated with significant decrease in infant birth weight of -59 g and gestational age by -0.2 week. Decreases observed in the cohorts in Kharkiv (-10 g and -0.1 week) and in Warsaw (-49 g and -0.2 week) were not statistically significant. Increase in p,p'-DDE concentration by one unit on the log scale was associated with a statistically significant decrease in infant birth weight of -39.4 g and -104.3 g and shortening of gestational age of -0.2 week and -0.6 week in the Inuit and Warsaw cohorts, respectively. In the Kharkiv cohort decrease in birth weight (-30.5 g) was not significant, however a shortening of gestational age of -0.2 week per increase in p,p'-DDE concentration by one unit on the log scale was of the borderline significance. There was no significant association between CB-153 and p,p'-DDE concentrations and risk of preterm birth however, in all cohorts the odds ratio was above 1.Conclusions: In utero exposure to POPs may reduce birth weight and gestational age of newborns however, new insights as to why results vary across studies were not apparent. [ABSTRACT FROM AUTHOR]