Common Source Of Exposure Research Articles

Selection and Characterization of an RNA-Cleaving DNAzyme Activated by Legionella pneumophila.

Legionella pneumophila is a deadly bacterial pathogen that has caused numerous Legionnaires' disease outbreaks, where cooling towers were the most common source of exposure. Bacterial culturing is used for L. pneumophila detection, but this method takes approximately 10 days to complete. In this work, an RNA-cleaving fluorogenic DNAzyme, named LP1, was isolated. Extensive characterization revealed that LP1 is reactive with multiple infectious isolates of L. pneumophila but inactive with 25 other common bacterial species. LP1 is likely activated by a protein target, capable of generating a detectable signal in the presence of as few as 10 colony-forming units of L. pneumophila, and able to maintain its activity in cooling tower water from diverse sources. Given that similar DNAzymes have been incorporated into many sensitive assays for bacterial detection, LP1 holds the potential for the development of biosensors for monitoring the contamination of L. pneumophila in exposure sources.

Isolation of the effects of alpha-related components from total effects of radium at low doses

Purpose Radium is the most common source of alpha radiation exposure to humans and non-human species in the environment but the dosimetry is complicated by the decay chain which involves gamma exposure due to radon daughters. This paper seeks to determine the separate contributions of alpha and gamma doses to the total dose and total direct and non-targeted effect in a fish and a human cell line. Materials and methods This study aimed to isolate the effect of alpha particles following exposure to low doses of radium in cells, and their progeny which received no further exposure. This was initially done by comparing the survival values of a human keratinocyte cell line (HaCaT) and an embryonic Chinook salmon cell line (CHSE-214) exposed to gamma radiation, from survival of the same cell lines exposed to mixed alpha and gamma radiation through exposure to Ra-226 and its decay products. A Monte Carlo simulation was later performed to determine the contributions of radium decay products including radon daughters. Results The human cell line showed increased radioresistance when exposed to low doses of alpha particles. In contrast the fish cell line, which demonstrated radioresistance to low dose gamma radiation, showed increased lethality when exposed to low doses of alpha particles. Significant and complex levels of non-targeted effects were induced in progeny of irradiated cells. The simulation showed that gamma and beta decay products did not contribute significant dose and the highest beta dose was below the threshold for inducing non-targeted effects. Conclusions The results confirm the need to consider the dose-response relationship when developing radiation weighting factors for low dose exposures, as well as the need to be aware of possible cell line and species differences.

Awareness of adverse effects of lead-containing cosmetics among the adolescence and young adult population in Chennai. A survey

Background: Lead and it’s compound induced health problems are continue to be an important, preventablepublic health issue. The common source of lead exposure in modern days is cosmetic products.Aim and Objectives: The study aims to evaluate the awareness about the adverse effects of lead-containingcosmetics in adolescence and the young adult population including factors influencing customers, knowledgeabout the product ingredients, and quality.Materials and Method: In this study, a questionnaire was prepared using Google form and circulatedamong the adolescence and young adult subjects to assess the awareness about the adverse effect of lead incosmetics. The study sample comprised of totally 203 participants of both males and females with the agegroup between 16 to 24 years.Results: In this study, it is found that 87% of the participants were aware that cosmetic products harm theirhealth. 78% of the participants know lead and its compounds present in the cosmetics. 86% of participantshave the habit of checking the ingredients and quality of cosmetic products. About 96% of the participantswere influenced by the advertisement of the product before buying it.

Co-exposure of Bi2O3 nanoparticles and bezo[a]pyrene-enhanced in vitro cytotoxicity of mouse spermatogonia cells.

Recent attention has been focused on reproductive toxicity of nanoscale materials in combination with pre-existing environmental pollutants. Due to its unique characteristics, bismuth (III) oxide (Bi2O3) nanoparticles (BONPs) are being used in diverse fields including cosmetics and biomedicine. Benzo[a]pyrene (BaP) is a known endocrine disruptor that most common sources of BaP exposure to humans are cigarette smoke and well-cooked barbecued meat. Hence, joint exposure of BONPs and BaP in humans is common. There is scarcity of information on toxicity of BONPs in combination with BaP in human reproductive system. In this work, combined effects of BONPs and BaP in mouse spermatogonia (GC-1 spg) cells were assessed. Results showed that combined exposure of BONPs and BaP synergistically induced cell viability reduction, lactate dehydrogenase leakage, induction of caspases (-3 and -9) and mitochondrial membrane potential loss in GC-1 spg cells. Co-exposure of BONPs and BaP also synergistically induced production of pro-oxidants (reactive oxygen species and hydrogen peroxide) and reduction of antioxidants (glutathione and several antioxidant enzymes). Experiments with N-acetyl-cysteine (NAC, a reactive oxygen species scavenger) indicated that oxidative stress was a plausible mechanism of synergistic toxicity of BONPs and BaP in GC-1 spg cells. Present data could be helpful for future in vivo research and risk assessment of human reproductive system co-exposed to BONPs and BaP.

Clinical spectrum, transmission dynamics, outcome and hydroxychloroquine prophylaxis in COVID-19 positive health care workers at a tertiary care hospital

Introduction: Being at the forefront, health-care workers (HCWs) have been at an increased risk of developing COVID-19.Objectives: To understand the pattern of the clinical symptoms, transmission dynamics, intake of hydroxychloroquine (HCQ) prophylaxis and outcome in COVID-19 positive HCWs.Methods: One hundred and fifty-one COVID-19 infected HCWs were telephonically followed up to study the exposure details, clinical presentation, comorbidities, HCQ prophylaxis, outcome and further transmission to their families.Results: The most commonly infected were doctors 60 (39.74%), followed by nursing staff (22.52%) and office staff (13.25%). Only 40 (26.49%) of infected staff was posted in COVID area. The most common source of exposure were patients (33.11%), followed by fellow staff members (28.48%) and 13 (8.61%) had contracted the disease from their family. Fever (74.17%) was the most common symptom followed by myalgia (43.71%), anosmia (37.75), sore throat (33.77%), ageusia (31.13%) and dry cough (28.48%). Three (1.99%) HCWs expired due to COVID-19 and 23 (16.31%) transmitted infection to their family members.Conclusions: This study concludes that HCWs are at greater risk of acquiring infection, particularly while working in non COVID areas, contracting the virus mainly from patients and co-workers. They are also a potential source of onward transmission to their colleagues and family.

Prescription opioid use after vaginal delivery and subsequent persistent opioid use and misuse

Vaginal delivery is the most common reason for hospitalization in the United States, and approximately 30% of women fill an opioid prescription after vaginal delivery, making this a common source of opioid exposure in women of reproductive age. This study aimed to evaluate the effect of receiving an opioid prescription after vaginal delivery on the risk of subsequent persistent opioid use, opioid use disorders, and overdose. We assembled a nationwide cohort of Medicaid beneficiaries in the United States using the Medicaid Analytic eXtract 2009-2014. The study population included pregnant women who delivered vaginally between 2009 and 2013 and were continuously enrolled in Medicaid from 90 days before to 365 days after delivery. We identified patients with prescription opioids dispensed within 7 days of the date of vaginal delivery. Persistent opioid use was defined as ≥10 opioid fills or >120 days' supply dispensed from 30 to 365 days after delivery. Incident diagnoses of opioid use disorder and overdose were ascertained during the same interval. Propensity score matching was used to control for potential confounding factors. Among 459,829 pregnancies ending in vaginal deliveries, 140,807 (30.62%) had an opioid dispensed within 7 days of delivery. Overall, 5770 of 140,807 (4.10%) women who filled an opioid prescription vs 2668 of 319,022 (0.84%) unexposed women had subsequent persistent opioid use, with an unadjusted relative risk of 4.90 (95% confidence interval, 4.68-5.13) and a risk difference of 3.26% (95% confidence interval, 3.15-3.37). After propensity score matching, the risk remained higher among pregnancies with an opioid prescription dispensed, with a relative risk of 2.57 (95% confidence interval, 2.43-2.72) and a risk difference of 2.21% (95% confidence interval, 2.08-2.33), which was confirmed by the instrumental variable analysis with a risk difference of 1.31% (95% confidence interval, 1.06-1.56) by using the rate of opioid prescribing at the delivery facility in a given geographic region as the instrument. The adjusted relative risk of newly diagnosed opioid use disorder and overdose was 1.48 (95% confidence interval, 1.40-1.57) and 1.92 (95% confidence interval, 1.20-3.09), respectively. Opioid dispensing following vaginal delivery is associated with future persistent opioid use and misuse, independent of confounding factors. Opioid prescriptions to women after vaginal delivery should be avoided, except in rare circumstances.

Profiling of emerging and legacy per-/polyfluoroalkyl substances in serum among pregnant women in China.

Emerging per-/polyfluoroalkyl substances (PFASs), such as chlorinated polyfluorinated ether sulfonates (Cl-PFESAs), have been detected in human samples, yet investigation on their occurrence in pregnant women remains limited. Herein, ten legacy PFASs, branched perfluorooctanesulfonate (PFOS) and perfluorooctanoate (PFOA), two Cl-PFESAs, perfluoro-2-propoxypropanoic acid (HFPO-DA), and ammonium 4,8-dioxa-3H-perfluorononanoate (ADONA) were detected in serum samples from 480 pregnant women in Tianjin, China. The influencing effects of age, body mass index, gravidity, and parity were also evaluated. PFOS [geographic mean (GM): 7.05ng/mL], 6:2Cl-PFESA (GM: 5.31ng/mL), and PFOA (GM: 2.82ng/mL) were the dominant PFASs in the serum of pregnant women, while neither HFPO-DA nor ADONA was detectable in any serum. The serum concentration of Cl-PFESAs and 6:2Cl-PFESA/PFOS ratio in the present study were 2-5 times higher than that in previous studies of pregnant women in China. Serum concentrations of Cl-PFESAs were significantly correlated with all detected PFAAs (Spearman's Rho: 0.15-0.69, p<0.01) excepting perfluoropentanesulfonate (PFPeS), indicating common exposure sources for Cl-PFESAs and PFAAs and some particular exposure source for PFPeS. Younger age and multi-parity were associated with lower serum concentrations of PFOS and several perfluoroalkyl sulfonates but not associated with Cl-PFESAs or PFOA, suggesting an increasing exposure to Cl-PFESAs and PFOA which neutralized the impact of age and parity. Overall, this study indicated a relatively high exposure level and composition of 6:2Cl-PFESA in pregnant women in the north coast of China, which highlights the need to investigate the exposure sources in this area.

Association of exposure to polycyclic aromatic hydrocarbons and heavy metals with thyroid hormones in general adult population and potential mechanisms

Air pollution and fuel emissions are the common sources of human exposure to polycyclic aromatic hydrocarbons (PAHs) and heavy metals. Several studies have suggested potential associations between PAHs/heavy metals and thyroid hormones, however, reports have been inconsistent. In this study, we employed a subpopulation of the adults (n = 1254) who participated in the Korean National Environmental Health Survey 2015–2017, and investigated the association of PAHs and major heavy metals with thyroid hormones, and explored the underlying mechanisms of thyroid disruption. Four PAH metabolites and three heavy metals of lead (Pb), mercury (Hg), and cadmium (Cd) were measured either in urine or in total blood. In addition, thyroid hormones (T3 and T4), TSH, thyroxine-binding globulin (TBG), and thyroid autoantibodies were measured, and peripheral deiodinase activity (GD) and thyroid's secretory capacity (GT) were calculated. Urinary Hg was negatively associated with total T3 in both males and females, while it was positively associated with total T4 among females only. Urinary Hg was related to decreased GD and increased GT in both sexes. In contrast, urinary Cd was positively associated with total T3 and GD in both male and female populations. Urinary Cd also showed a positive association with thyroid autoantibodies, but only in males. A multi-factor model considering co-exposure to multiple chemicals also resulted in similar associations. Among the measured PAH metabolites, only urinary 1-hydroxypyrene showed a negative association with total T3 in males. However, this association was marginal, and disappeared in a multi-chemical model. The present observations are suggestive that exposures to Hg and Cd might disrupt thyroid hormones, possibly through an alteration of deiodinase activity. Association of PAH exposure with thyroid hormone appears to be insignificant.

Genetic diversity of clinical and environmental Mucorales isolates obtained from an investigation of mucormycosis cases among solid organ transplant recipients.

Mucormycoses are invasive infections by Rhizopus species and other Mucorales. Over 10 months, four solid organ transplant (SOT) recipients at our centre developed mucormycosis due to Rhizopus microsporus (n=2), R. arrhizus (n=1) or Lichtheimia corymbifera (n=1), at a median 31.5 days (range: 13–34) post-admission. We performed whole genome sequencing (WGS) on 72 Mucorales isolates (45 R. arrhizus, 19 R. delemar, six R. microsporus, two Lichtheimia species) from these patients, from five patients with community-acquired mucormycosis, and from hospital and regional environments. Isolates were compared by core protein phylogeny and global genomic features, including genome size, guanine–cytosine percentages, shared protein families and paralogue expansions. Patient isolates fell into six core phylogenetic lineages (clades). Phylogenetic and genomic similarities of R. microsporus isolates recovered 7 months apart from two SOT recipients in adjoining hospitals suggested a potential common source exposure. However, isolates from other patients and environmental sites had unique genomes. Many isolates that were indistinguishable by core phylogeny were distinct by one or more global genomic comparisons. Certain clades were recovered throughout the study period, whereas others were found at particular time points. In conclusion, mucormycosis cases could not be genetically linked to a definitive environmental source. Comprehensive genomic analyses eliminated false associations between Mucorales isolates that would have been assigned using core phylogenetic or less extensive genomic comparisons. The genomic diversity of Mucorales mandates that multiple isolates from individual patients and environmental sites undergo WGS during epidemiological investigations. However, exhaustive surveillance of fungal populations in a hospital and surrounding community is probably infeasible.

Assessing the impact of environmental and occupational cancer hazard assessments on policy decision-making: An analysis of US Federal and state regulations

Background: After an occupational or environmental carcinogen is identified as a human hazard, years often pass before policy decisions are enacted that will impact public health. Evaluating the informativeness of hazard assessments on science and regulatory policies is critically important but rarely undertaken. Additionally, no clear approaches exist to measure the influence of cancer hazard conclusions on science-based policy. Using the US Report on Carcinogens (RoC) by the National Toxicology Program, we aim to assess the use of cancer hazard assessments in Federal and state policies, public health impacts, and economic impacts associated with the public health impacts. Methods: We conducted a search of any mention of the RoC in the published regulations on the US Federal Register website, as well as state regulations included in Lexis Advance®. For each regulation, we extracted information on the carcinogen(s) regulated, environmental or occupational media, exposure pathways, tumor site, analyzed public health benefits, and metrics reported in the cost-benefit analysis. Results: Of the identified carcinogens in the RoC from 1994-2019, there were 76 regulations from 8 Federal and 6 state or district agencies that cited the RoC in the notice for regulatory action. The most frequently regulated RoC agents were 1,3-butadiene (N=12), acetaldehyde (N=13), formaldehyde (N=16), and benzene (N=14). The most common exposure sources regulated included air pollutants, manufacturing, and transportation. Of the 51 federal regulations identified, 28 were “economically significant” as defined in Executive Order 12866. The largest overall cancer-related economic benefit was a Federal regulation of occupational exposure to hexavalent chromium, a lung carcinogen. Discussion: Over 25 years, RoC cancer hazard assessments directly informed more than 76 health-based regulatory policies. Expansion of our approach to other cancer and noncancer hazard assessments may ultimately improve our understanding of the effectiveness of scientific conclusions on policymaking.

Normative formaldehyde-hemoglobin adduct levels among the US Population: Analysis of the 2013–2016 National Health and Nutrition Examination Survey

IntroductionFormaldehyde (FA) is currently classified as a known carcinogen. In addition to being a ubiquitous compound with many common exogenous exposure sources, it is also part of multiple metabolic pathways and present in every living cell. The objectives of this study were to determine normative levels of FA as measured by FA-Hemoglobin (Hb) adducts in the United States (US) and to determine if FA-Hb levels differ based on a variety of demographic factors. MethodsData collected between 2013 and 2016 by the National Health and Nutrition Examination Survey were assessed from 4521 participants representing approximately 244 million individuals living in the US. General linear models were used to examine associations between FA-Hb adducts and sample characteristics. FA-Hb levels were summarized using geometric mean concentrations (GMC) and associated 95% confidence intervals (CI). ResultsThe overall GMC was 131.10 nmol/g Hb (95% CI 129.39–132.83). Analyses revealed no evidence to support associations between FA-Hb levels and age, gender, income, or nicotine use. Among adults, non-Hispanic Black race was associated with lower FA-Hb levels compared to all other race/ethnicity groups, P < 0.01. ConclusionThe study provides the first normative values for FA in adults and children. These data could be a tool to assess the body’s response to acute and chronic exposure.

Bir Çalışma Ortamında Bulunan Trafo Etrafındaki Oldukça Düşük Frekanslı Manyetik Alanların Ölçümü ve Risk Değerlendirilmesi

Transformers present the most common source of exposure to excessive extremely low frequency (ELF) magnetic fields (MFs). A transformer is an electrical device that transfers electrical energy between two or more circuits through electromagnetic induction. Nowadays the effects of extremely low frequency electromagnetic (EM) fields on health have been discussed frequently but there is few measurement studies performed around various transformers for workers. In this study, the leakage fields around transformers and enclosures site were measured in Ankara and evaluated in terms of standards. It has been observed that people were exposed to ELF-MFs above International Agency for Research on Cancer (IARC) cancer limits. Many people reported health complaints such as being tired in most working hours, immunological complaints, dizziness, some cancer cases are also observed there. In these systems areas safe distances or areas for people should be realized and precautions should therefore be taken to minimize the fields exposed

Clusters of COVID-19 associated with Purim celebration in the Jewish community in Marseille, France, March 2020

ObjectivesWe investigated possible COVID-19 epidemic clusters and their common sources of exposure that led to a sudden increase in the incidence of COVID-19 in the Jewish community of Marseille between March 15 and March 20, 2020. MethodsAll data were generated as part of routine work at Marseille university hospitals. Biological diagnoses were made by RT-PCR testing. A telephone survey of families in which a laboratory confirmed case was diagnosed was conducted to determine possible exposure events. ResultsAs of March 30, 2020, 63 patients were linked to 6 epidemic clusters. The 6 clusters were linked to religious and social activities: a ski trip, organized meals for the Purim Jewish celebration in community and family settings on March 10, a religious service and a charity gala. Notably, 40% of the patients were infected by index patients during the presymptomatic period, which was 2.5 days before symptom onset. When considering household members, all 12 patients who tested negative and who did not develop any relevant clinical symptoms compatible with COVID-19 were 1–16 years of age. The clinical attack rate (symptoms compatible with COVID-19, and biologically confirmed by PCR) in adults was 85% compared to 26% in children. ConclusionsFamily and community gatherings for the Purim Jewish celebration probably accelerated the spread of COVID-19 in the Marseille Jewish community, leading to multiple epidemic clusters. This investigation of family clusters suggested that all close contacts of patients with confirmed COVID-19 who were not infected were children.

Cellular response to chemicals present in air pollution in occupationally exposed workers and its potential cancer susceptibility

The study aimed to evaluate the potential effects of the chronic exposure to chemical agents from air pollution on phenotypic and genotypic expressions of peripheral biomarkers and tumor-related proteins in mononuclear cells. This study evaluates 85 taxi drivers (outdoor workers) and 55 non-occupationally exposed persons (NOE) to air pollution (indoor workers). The biomarkers were urinary 1-hydroxypyrene (1-OHP), for organic agents, and blood As and Ni, for inorganic agents. Oxidative stress biomarkers; protein expression of ICAM-1 (CD54), β2-integrin, L-selectin (CD62-L), and MCP1; gene expression of ICAM-1, p53 and CD26 were performed. Urinary 1-OHP and blood As and Ni levels were increased in taxi drivers and were associated with inflammatory and oxidative stress biomarkers. These exposure biomarkers were also associated with each other, suggesting a common source of exposure. The gene expression of p53, CD26 and ICAM-1 were decreased in taxi drivers and were strongly associated between them, indicating a commom regulation point. The antioxidant non-protein thiols and lycopene were negatively associated with inflammatory biomarkers, maybe regulating the immune-response. We demonstrated, for the first time, that in occupational exposure to air pollution chemicals, oxidative and inflammatory processes are involved in the immune-regulatory process, and indirectly contribute to suppressing the p53 and CD26 expressions, increasing the risk of cancer development. On the other hand, antioxidants could contribute to improving the immune-regulation, but more studies are needed.

Clinical features of children with carbon monoxide intoxication: a single center study

Purpose To investigate the effect of lifestyle changes on patterns of carbon monoxide (CO) exposure and the association between neurologic symptoms and outcomes in Korean children with CO intoxication. Methods We reviewed the medical records of patients (< 18 years) with CO intoxication who visited the emergency department of Pusan National University Hospital between February 2012 and January 2020. We collected clinical findings, including age and sex, transfer from other hospitals, source, time and duration of exposure, manifestations with neurologic symptoms (syncope, seizure, and altered mental status), intensive care unit hospitalization, hospital length of stay, implementation of hyperbaric oxygen therapy, and findings of neuroimaging. These variables were compared between children with and without neurologic symptoms. In addition, levels of carboxyhemoglobin and lactate were compared between patients with and without specific manifestations. Results The enrolled 47 patients’ median age was 10 years (interquartile range, 4.5-14.0). The most common source of exposure was fire (46.8%), followed by camping (23.4%). The most common times of exposure were night (44.7%) and winter (44.7%). The patients with neurologic symptoms (14 [29.8%]) showed longer duration of exposure and hospital length of stay (P < 0.001 and P = 0.007, respectively). Of the 14 patients, 2 were hospitalized to the intensive care unit without an in-hospital mortality. A significant association was found between dyspnea and lactate level (P = 0.049), also between syncope or presyncope and carboxy hemoglobin level (P = 0.017). Conclusion CO intoxication in Korean children is most often caused by fire and camping, and at night and in winter. There is a correlation between neurologic symptoms and duration of exposure to CO. Key Words: Carbon Monoxide; Carboxyhemoglobin; Child; Hyperbaric Oxygenation; Neurologic Manifestations; Poisoning

Economic valuation of health benefits from using geologic data to communicate radon risk potential

BackgroundRadon exposure is the second leading cause of lung cancer worldwide and represents a major health concern within and outside the United States. Mitigating exposure to radon is especially critical in places with high rates of tobacco smoking (e.g., Kentucky, USA), as radon-induced lung cancer is markedly greater among people exposed to tobacco smoke. Despite homes being a common source of radon exposure, convincing homeowners to test and mitigate for radon remains a challenge. A new communication strategy to increase radon testing among Kentucky homeowners utilizes fine-scale geologic map data to create detailed radon risk potential maps. We assessed the health benefits of this strategy via avoided lung cancer and associated premature mortality and quantified the economic value of these benefits to indicate the potential utility of using geologic map data in radon communication strategies.MethodsWe estimated the change in radon testing among all 120 counties in Kentucky following a new communication strategy reliant on geologic maps. We approximated the resultant potential change in radon mitigation rates and subsequent expected lung cancer cases and mortality avoided among smokers and non-smokers exposed to 4 pCi/L of radon in the home. We then applied the value of a statistical life to derive the economic value of the expected avoided mortality.ResultsThe new communication strategy is estimated to help 75 Kentucky residents in 1 year avoid exposure to harmful radon levels via increased testing and mitigation rates. This equated to the potential avoidance of approximately one premature death due to lung cancer, with a net present value of $3.4 to $8.5 million (2016 USD).ConclusionsOur analysis illustrates the potential economic value of health benefits associated with geologic map data used as part of a communication strategy conveying radon risk to the public. Geologic map data are freely available in varying resolutions throughout the United States, suggesting Kentucky’s radon communication strategy using geologic maps can be employed in other states to educate the public about radon. As this is only a single application, in a single state, the economic and health benefits of geologic map data in educating the public about radon are likely to exceed our estimates.

Exposure sources of perfluoroalkyl acids and influence of age and gender on concentrations of chlorinated polyfluorinated ether sulfonates in human serum from China

The presence of perfluoroalkyl acids (PFAAs) and chlorinated polyfluoroalkyl ether sulfonates (Cl-PFAESs) in humans has attracted great attention in recent decades. However, information on their exposure sources and the influence of age and gender on Cl-PFAES concentrations in human serum is still limited. In this study, eighty-five serum samples were collected from the general population in Anji, China, and analyzed for perfluoroalkyl carboxylates (PFCAs), perfluoroalkyl sulfonates (PFSAs), and Cl-PFAESs. Perfluorooctane sulfonate (PFOS; mean, 5.9 ng/mL) and perfluorooctanoate (PFOA; 3.3 ng/mL) were the predominant PFAAs in human serum. The serum concentrations of C8–C12 PFCAs, perfluorohexane sulfonate, and PFOS were significantly (rs = 0.40–0.98, p < 0.01) correlated with one another. In human serum, the mean percentages of branched isomers for PFOA, perfluorohexane sulfonate, and PFOS were 97.3%, 92.6%, and 66%, respectively. These results suggest that the major source of PFCAs and PFSAs in human serum was direct exposure. The mean 6:2Cl-PFAES (6.0 ng/mL) serum concentration was higher than PFOA (p < 0.01). The mean 6:2Cl-PFAES concentrations in male and female serum were 6.5 ng/mL and 5.6 ng/mL, respectively. A significant increase in 6:2Cl-PFAES concentrations with age was found in males (rs = 0.50, p = 0.001). The 6:2Cl-PFAES concentration was positively correlated with C8–C12 PFCAs and PFOS in human serum (rs = 0.44–0.91, p < 0.01), indicating that they may have common exposure sources. Overall, this study first investigated the roles of age and gender on human serum concentrations of Cl-PFAESs and provided baseline information on the occurrence of Cl-PFAESs in the general Chinese population.

Chronic hypersensitivity pneumonitis in the southeastern United States: an assessment of how clinicians reached the diagnosis

BackgroundChronic hypersensitivity pneumonitis (cHP) is a disease caused by exposure to inhaled environmental antigens. Diagnosis of cHP is influenced by the awareness of the disease prevalence, which varies significantly in different regions, and how clinicians utilize relevant clinical information. We conducted a retrospective study to evaluate how clinicians in the Southeast United States, where the climate is humid favoring mold growth, diagnosed cHP using items identified in the international modified Delphi survey of experts, i.e., environmental exposure, CT imaging and lung pathology,MethodsWe searched Duke University Medical Center database for patients over the age of 18 with a diagnosis of cHP (ICD-9 code: 495) between Jan. 1, 2008 to Dec. 31, 2013 using a query tool, Duke Enterprise Data Unified Content Explorer (DEDUCE).ResultsFive hundred patients were identified and 261 patients had cHP confirmed in clinic notes by a pulmonologist or an allergist. About half of the patients lived in the Research Triangle area where our medical center is located, giving an estimated prevalence rate of 6.5 per 100,000 persons. An exposure source was mentioned in 69.3% of the patient. The most common exposure sources were environmental molds (43.1%) and birds (26.0%). We used Venn diagram to evaluate how the patients met the three most common cHP diagnostic criteria: evidence of environmental exposures (history or precipitin) (E), chest CT imaging (C) and pathology from lung biopsies (P). Eighteen patients (6.9%) met none of three criteria. Of the remaining 243 patients, 135 patients (55.6%) had one (E 35.0%, C 3.3%, P 17.3%), 81 patients (33.3%) had two (E + C 12.3%, E + P 17.3%, C + P 4.9%), and 27 patients (11.1%) had all three criteria (E + C + P). Overall, 49.4% of patients had pathology from lung biopsy compared to 31.6% with CT scan.ConclusionsEnvironmental mold was the most common exposure for cHP in the Southeast United States. Lung pathology was available in more than half of cHP cases in our tertiary care center, perhaps reflecting the complexity of referrals. Differences in exposure sources and referral patterns should be considered in devising future diagnostic pathways or guidelines for cHP.

Phthalate metabolites concentrations in amniotic fluid and maternal urine: Cumulative exposure and risk assessment

Phthalates are used in industry as plasticizers or additives in everyday products and they have been considered as endocrine disrupting chemicals. Maternal exposure during pregnancy has been associated with neonatal exposure, preterm birth and impacts in the reproductive and respiratory systems. The aim of this study is to determine six phthalate metabolites (mono isobutyl phthalate, miBP, mono n-butyl phthalate, mnBP, mono benzyl phthalate, mBzP, mono ethylhexyl phthalate, mEHP, mono 2-ethyl-5-hydroxyhexyl phthalate, mEHHP, mono 2-ethyl-5-oxohexyl-phthalate, mEOHP) in amniotic fluid and urine from 100 pregnant women. Participants answered questionnaires for the use of plastics and cosmetics, dietary habits, health effects, pregnancy problems, health and infant development. Positive amniotic fluid samples ranged from 1% to 21% and urine from 27% to 54%. The median levels for amniotic fluid were 2.3 μg/L - 10.7 μg/L and for urine 4.9 μg/L - 46.7 μg/L. The major results include significant correlations between urinary phthalates indicating their common sources of exposure, the frequent use of deodorant was significantly associated with higher urinary miBP (p = 0.050) and mnBP (p = 0.028) and a weak inverse association was found for the use of make-up products with mBzP (p = 0.053). The frequent use of plastic food containers was significantly associated with urinary mEHP (p = 0.026), and a positive trend was noticed for mEHP in amniotic fluid (p = 0.093). An association although weak was found between urinary mEHP and lower birth length (rs = 0.396, p = 0.062). No other associations were found for infant health problems or development. The daily intake of the total phthalates was calculated 5.4 μg/kg body weight/day which corresponds to hazard index 0.10 and exposure follows the declining trend that has been observed the last decades.

Sources and Biomarkers of Secondhand Tobacco Smoke Exposure in Urban Adolescents.

In an urban adolescent population, we evaluated sources of exposure to secondhand smoke exposure (SHS), examined differences in exposure by race/ethnicity, age and sex, and determined the relationship between exposure source(s) and the biomarkers cotinine and NNAL. Participants were recruited from a public hospital-based outpatient clinic in San Francisco, CA, USA. Of a sample of N=298 adolescents screened, 235 were biologically confirmed to be exposed to tobacco smoke. Of those, N=16 were active smokers and N=219 were exposed to SHS; 91 (39%) were heavily SHS exposed (median cotinine=0.76 ng/mL) and 128 (54%) had light SHS exposure (median cotinine=0.11 ng/mL). Within those SHS exposed, the most common source of exposure was in a public area. No significant racial/ethnic differences were found, although African American adolescents were more likely to live in a home that allowed smoking. Older adolescents were more likely to be exposed across several difference sources, and females more likely to be exposed in a car and in public areas. Past 7-day exposure in the home, in a car, and current blunt use were significantly related to biomarkers of exposure. Urban adolescents are exposed to SHS across a variety of sources. Although exposure in a public area is most common, exposure in the home and in cars significantly influences tobacco biomarker levels. Interventions to reduce exposure would have the greatest impact in this population if they focused on reducing exposure in the home and in cars. History of blunt use is a strong determinant of tobacco exposure.