1
|
Attiya N, Fattahi R, Amarouch MY, El-Haidani A, El Jaafari S, Filali-Zegzouti Y. Mercurial risk from dental amalgam use in a population of Moroccan dentists: A latent class regression approach. INTERNATIONAL JOURNAL OF RISK & SAFETY IN MEDICINE 2023; 34:313-323. [PMID: 37355914 DOI: 10.3233/jrs-210052] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/26/2023]
Abstract
BACKGROUND Dentists using dental amalgam are chronically exposed to low doses of elemental mercury. The complex toxico-kinetics of this systemic toxicant results in polymorphic and variable clinical phenotypes. In this context, adapted statistical methods are required to highlight potential adverse effects of occupational mercury exposure on dentists' health. OBJECTIVE The present study aims to analyze the distribution of self-reported subjective symptoms, commonly associated with chronic mercury poisoning, according to occupational mercury exposure in a population of Moroccan liberal dentists. METHODS In order to achieve the defined objectives, a three-step latent class regression was fitted. First a latent class analysis was performed to cluster the studied population according to their declared symptoms. Dentists were then classified in the defined latent classes based on their posterior probabilities. Finally, a logistic regression is fitted to identify predictors associated with the latent classes' membership. RESULTS The final obtained model showed acceptable calibration and discrimination. Its interpretation revealed that the increase of the frequency of amalgam use was associated with significant higher odds of belonging to the high risk latent class. CONCLUSIONS The present study represents an initial step towards the development of diagnosis model that predict clinical profiles according to occupational mercury exposure.
Collapse
Affiliation(s)
- Nourdine Attiya
- B.A.S.E Laboratory, Moulay Ismail University, Meknes, Morocco
- Cluster of Competence on Health & Environment, Moulay Ismail University/VLIR-UOS, Meknes, Morocco
| | - Rkia Fattahi
- B.A.S.E Laboratory, Moulay Ismail University, Meknes, Morocco
- Higher Institute of Nursing Professions and Health Techniques, Errachidia, Morrocco
| | - Mohamed-Yassine Amarouch
- R.N.E Laboratory, Multidisciplinary Faculty of Taza, Sidi Mohammed Ben Abdellah University, Fez, Morocco
| | - Ahmed El-Haidani
- Ethnopharmacology and Pharmacognosy Team, Faculty of Sciences and Technology of Errachidia, Moulay Ismail University, Meknes, Morocco
| | - Samir El Jaafari
- B.A.S.E Laboratory, Moulay Ismail University, Meknes, Morocco
- Cluster of Competence on Health & Environment, Moulay Ismail University/VLIR-UOS, Meknes, Morocco
| | - Younes Filali-Zegzouti
- B.A.S.E Laboratory, Moulay Ismail University, Meknes, Morocco
- Cluster of Competence on Health & Environment, Moulay Ismail University/VLIR-UOS, Meknes, Morocco
| |
Collapse
|
2
|
Attiya N, Filali A, Fattahi R, Moujane S, Mazouz H, Amarouch MY, Filali-Zegzouti Y. Modeling Subjective Symptoms Related to Micro-Hydrargyrism in a Population of Moroccan Dentists. Ethiop J Health Sci 2021; 31:147-158. [PMID: 34158762 PMCID: PMC8188101 DOI: 10.4314/ejhs.v31i1.17] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022] Open
Abstract
Background The ability of mercury to deposit throughout the body and alter a wide range of molecular and cellular pathways results in a polymorphic and complex clinical phenotype with over 250 possible symptoms. However, some of them are recurrently cited as evoking chronic mercury poisoning. In this light, dentists users of dental amalgams are chronically exposed to mercury so that in-depth epidemiological investigations and adapted statistical methods are required to highlight adverse effects of this exposure. Methods In order to study the health impact of the occupational mercury exposure in a population of liberal dentists practicing in two Moroccan regions, a list of eighteen subjective symptoms commonly associated with micro-hydrargyrism was drawn up. Then, seven statisctical models adapted to count data were fitted. Finally, three methods were used to compare their relative performance in order to choose the most appropriate one. Results The adopted logical path, from the response variable selection till models' comparison, led us to lean towards quasi-Poisson regression as the best way to predict the number of symptoms declared by dentists according to mercury exposure. Conclusions Interpretation of the selected model allowed us to conclude that the reduction of dental amalgam use allows the reduction of subjective symptoms related to mercury exposure.
Collapse
Affiliation(s)
- Nourdine Attiya
- B.A.S.E Laboratory, Department of Biology, Faculty of Sciences and Techniques of Errachidia, Moulay Ismail University, Morocco
| | - Ayoub Filali
- Higher Institute of Nursing Profession and Techniques of Health, Kenitra, Morocco.,Faculty of Science, Ibn Tofail University, Kenitra, Morocco
| | - Rkia Fattahi
- B.A.S.E Laboratory, Department of Biology, Faculty of Sciences and Techniques of Errachidia, Moulay Ismail University, Morocco
| | - Soumia Moujane
- B.A.S.E Laboratory, Department of Biology, Faculty of Sciences and Techniques of Errachidia, Moulay Ismail University, Morocco
| | - Hamid Mazouz
- P.B.M.B Laboratory, Department of Biology, Faculty of Science, Moulay Ismail University, Meknes, Morocco
| | - Mohamed-Yassine Amarouch
- R.N.E Laboratory, Multidisciplinary Faculty of Taza, Sidi Mohammed Ben Abdellah University, Fez, Morocco
| | - Younes Filali-Zegzouti
- B.A.S.E Laboratory, Department of Biology, Faculty of Science, Moulay Ismail University, Meknes, Morocco
| |
Collapse
|
3
|
Jonidi Jafari A, Esrafili A, Moradi Y, Mahmoudi N. Mercury level in biological samples of dentists in Iran: a systematic review and meta-analysis. JOURNAL OF ENVIRONMENTAL HEALTH SCIENCE & ENGINEERING 2020; 18:1655-1669. [PMID: 33312669 PMCID: PMC7721756 DOI: 10.1007/s40201-020-00558-w] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/26/2020] [Accepted: 09/29/2020] [Indexed: 05/09/2023]
Abstract
Exposure to mercury is an important risk to dentists health. The aim of the present study was to assess the pooled mean mercury level (MML) in the urine, blood, nail, and hair of Iranian dentists (IDs) through the meta-analysis technique. Comprehensive and systematic searches were performed in main local databases including SID, Magiran, Iran medex, and ISC as well as internationally available databases including Embase, PubMed and Scopus for all the relevant studies up to 2018. In order to prevent bias in this study and identify eligible studies, various steps of the study was performed independently by two researchers. Out of 13 studies in the meta-analysis process which included 1499 IDs, the mean of the mercury level in the urine, nail, and blood was estimated to be 6.29 (95% CI: 2.61-9.97, I-square: 62.7%, P: 0.006), 3.54 (95% CI: 2.81-4.28, I-square: 0.0%, P: 0.968), 11.20 (95% CI: 2.28-20.13, I-square: 59.9%, P: 0.082), respectively. The mean mercury level (MML) in the biological samples of IDs was higher than the standard of World Health Organization (WHO). So, in accordance with Article 10 of the European Union Regulations (EUR), in the context of the Minamata Convention (MC) on Dental Amalgam (DA), in order to avoid the dangers of mercury exposure in dentists, it is necessary for Iran and other countries to approve laws and to implement a national plan to reduce mercury levels and replace the appropriate materials.
Collapse
Affiliation(s)
- Ahmad Jonidi Jafari
- Research Center for Environmental Health Technology, Iran University of Medical Sciences, Tehran, Iran
- Department of Environmental Health Engineering, School of Public Health, Iran University of Medical Sciences, Tehran, Iran
| | - Ali Esrafili
- Research Center for Environmental Health Technology, Iran University of Medical Sciences, Tehran, Iran
- Department of Environmental Health Engineering, School of Public Health, Iran University of Medical Sciences, Tehran, Iran
| | - Yousef Moradi
- Department of Epidemiology, School of Public Health, Iran University of Medical Sciences, Tehran, Iran
| | - Norouz Mahmoudi
- Research Center for Environmental Health Technology, Iran University of Medical Sciences, Tehran, Iran
- Department of Environmental Health Engineering, School of Public Health, Iran University of Medical Sciences, Tehran, Iran
- Health Research Center, Life style Institute, Baqiyatallah University of Medical Sciences, Tehran, Iran
| |
Collapse
|
4
|
Attiya N, Fattahi R, El-Haidani A, Lahrach N, Amarouch MY, Filali-Zegzouti Y. [Mercury exposure and dentists' health status in two regions of centrall Morocco: descriptive cross-sectional survey]. Pan Afr Med J 2020; 36:110. [PMID: 32821321 PMCID: PMC7406463 DOI: 10.11604/pamj.2020.36.110.19623] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2019] [Accepted: 05/11/2020] [Indexed: 12/14/2022] Open
Abstract
INTRODUCTION mercury exposure is recognized as a worldwide public health concern. However, the effect of long-term exposure to low-doses of this heavy metal is still subject to debate. Due to the use of mercury in dental amalgam, dental health care professionals are chronically exposed to low-doses of this metal. In this context, we have conducted a descriptive cross-sectional survey among liberal dentists in two regions of the center of Morocco. In parallel, the global health status of participants was investigated to assess the relevance of a subsequent etiological survey. METHODS data were collected through a self-reported questionnaire. Occupational exposure of dentists to mercury was evaluated based on their use of dental amalgam. Moreover, the other common factors increasing the background pollution or inducing exposure peaks were also investigated. On the other hand, smoking, vaccination, fish consumption, and the number of dental amalgam in mouth were considered as non-occupational exposure sources. Finally, the self-reported global health problems of participants were collected. RESULTS 192 dentists were included in the present study. Seventy-six percent (76.04%) of them declared using dental amalgam in their practice. Moreover, the presence of dental amalgam in mouth was identified as the main non-occupational source of exposure to mercury (63.45% of participants). Finally, most of participants (46.35%) have expressed neuropsychological complaints. CONCLUSION altogether, our results revealed a real mercury exposure in the studied population. Thus, effective preventive measures should be promoted to minimize the mercury exposure in dental offices. Moreover, an etiological study will be of great interest to reveal the impact of mercury exposure in this population.
Collapse
Affiliation(s)
- Nourdine Attiya
- Laboratoire Bioactifs, Santé et Environnement, Université Moulay Ismaïl, Meknès, Maroc
| | - Rkia Fattahi
- Laboratoire Bioactifs, Santé et Environnement, Université Moulay Ismaïl, Meknès, Maroc
- Institut Supérieur des Professions Infirmières et Techniques de Santé, Errachidia, Maroc
| | - Ahmed El-Haidani
- Equipe Ethnopharmacologie et Pharmacognosie, Faculté des Sciences et Technique Errachidia, Université Moulay Ismaïl, Maroc
| | - Nadia Lahrach
- Equipe Ethnopharmacologie et Pharmacognosie, Faculté des Sciences et Technique Errachidia, Université Moulay Ismaïl, Maroc
| | - Mohamed-Yassine Amarouch
- Laboratoire Ressources Naturelles et Environnement, Faculté Polydisciplinaire de Taza, Université Sidi Mohamed Ben Abdellah de Fès, Fès, Maroc
| | | |
Collapse
|
5
|
Association between Dental Amalgam Filling and Essential Tremor: A Nationwide Population-Based Case Control Study in Taiwan. INTERNATIONAL JOURNAL OF ENVIRONMENTAL RESEARCH AND PUBLIC HEALTH 2020; 17:ijerph17030780. [PMID: 32012693 PMCID: PMC7037675 DOI: 10.3390/ijerph17030780] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 12/31/2019] [Revised: 01/23/2020] [Accepted: 01/24/2020] [Indexed: 11/17/2022]
Abstract
Essential tremor (ET) is a common neurological disorder and the most common movement disorder. Low-level occupational exposure to mercury vapor is known to be a crucial factor that increases the risk of tremor. Dental amalgam is one of the main sources of mercury in those who possess amalgam restorations. However, the relationship between ET and amalgam filling (AMF) is not quite clear. The purpose of this study was to investigate the association between AMF and the risk of ET using a population-based administrative databank. The data for this study were sourced from the Taiwanese National Health Insurance Research Database (NHIRD). A retrospective case-control study was conducted using this databank from 2000 to 2013. Case and control groups were matched by sex, age, urbanization level, monthly income, and Charlson comorbidity index using the propensity score method with a 1:1 ratio. In this study, 3008 cases and 3008 controls were included. The results from this nationwide population-based case-control study did not indicate any association between ET and AMF in Taiwan. Although the results were not significantly statistical, the findings may be worthy to be valued.
Collapse
|
6
|
Research on Hyperspectral Identification of Altered Minerals in Yemaquan West Gold Field, Xinjiang. SUSTAINABILITY 2019. [DOI: 10.3390/su11020428] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Predictions of prospectivity based on remote sensing were developed using alteration mineral indicative hyperspectral mapping and remote sensing anomaly filtering, combined with geological characteristics and anomalous mineral field verification. Based on the results of the hyperspectral mineral mapping and the actual geological ground conditions, the results of mapping of altered minerals, such as chlorite, muscovite, kaolinite, and iron oxide were validated, and gold, silver, copper, nickel, and other geochemical anomaly areas were identified for verification work. The results of hyperspectral mineral extraction show that the mineral assemblage closely related to gold deposits in shear zones is muscovite + chlorite + epidote + kaolinite. This alteration mineral assemblage can be used as regional search criteria for shear zone gold mineralisation and was the basis for the discovery of mineralised hydrothermal alteration centres and delineation of four prospective targets. Established on a spectral prospectivity model of the study area, prospective ore-bearing areas have been delineated, which indicate the direction for further geological and mineral resource surveys.
Collapse
|
7
|
Aaseth J, Hilt B, Bjørklund G. Mercury exposure and health impacts in dental personnel. ENVIRONMENTAL RESEARCH 2018; 164:65-69. [PMID: 29482185 DOI: 10.1016/j.envres.2018.02.019] [Citation(s) in RCA: 30] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/09/2018] [Revised: 02/11/2018] [Accepted: 02/13/2018] [Indexed: 05/24/2023]
Abstract
Based on toxicological, clinical, and epidemiological knowledge, the present paper reviews the status regarding possible deleterious health effects from occupational exposure to metallic mercury (Hg) in dental practice. Symptoms from the central nervous system are among the health problems that most often are attributed to Hg exposure in dentists and dental nurses working with amalgam. Uncharacteristic symptoms of chronic low-level Hg vapor exposure including weakness, fatigue, and anorexia have been observed in numerous studies of dental personnel. It is crucial to protect both human health and the environment against negative effects of Hg. In line with this, the use of dental amalgam in industrial countries is about to be phased out. In Norway and Sweden, the use of the filling material is banned.
Collapse
Affiliation(s)
- Jan Aaseth
- Research Department, Innlandet Hospital Trust, Brumunddal, Norway; Faculty of Health and Social Sciences, Inland Norway University of Applied Sciences, Elverum, Norway.
| | - Bjørn Hilt
- Department of Occupational Medicine, St. Olav's University Hospital, Trondheim, Norway; Department of Public Health and Nursing, Faculty of Medicine and Health Sciences, Norwegian University of Science and Technology, Trondheim, Norway
| | - Geir Bjørklund
- Council for Nutritional and Environmental Medicine, Mo i Rana, Norway.
| |
Collapse
|
8
|
Çağlar Y, Biyiklioglu Z. Spectrophotometric determination of Hg(II) in water samples by dispersive liquid liquid microextraction with use ionic liquid after derivatization with a water soluble Fe(II) phthalocyanine. J INCL PHENOM MACRO 2018. [DOI: 10.1007/s10847-018-0780-6] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
|
9
|
Al-Zubaidi ES, Rabee AM. The risk of occupational exposure to mercury vapor in some public dental clinics of Baghdad city, Iraq. Inhal Toxicol 2017; 29:397-403. [PMID: 29043874 DOI: 10.1080/08958378.2017.1369601] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
BACKGROUND Dental workers are exposed to elevated levels of elemental mercury vapor substantially above the occupational exposure standards when placing or removing mercury/silver tooth restorations and disposing of mercury waste. This results in a significant increase in occupational exposure and risk of mercury intoxication. METHODS To evaluate the occupational exposure of dental workers to amalgam in four dental clinics in Baghdad city, the concentrations of mercury vapor were measured seasonally from February to November 2016. Samples of blood and urine were collected from 30 dental workers (exposed individuals) and five non-occupationally exposed individuals. Biochemical parameters such as cholesterol, liver enzymes (alanine aminotransferase, aspartate aminotransferase and alkaline phosphatase), renal enzymes (urea and creatinine), total protein and reduced glutathione (GSH) were observed. RESULTS The results indicated that mercury vapor levels varied from 84.7 ± 18.67 to 609.3 ± 238.90 µg/m3 and most concentrations were above the occupational exposure standards. The results of the biochemical parameters showed a significant increase in levels of cholesterol, aspartate aminotransferase (AST) and alanine aminotransferase (ALT) and no significant increase in blood urea and creatinine in dental workers in comparison with unexposed persons (control). Although the results showed a significant reduction in the levels of glutathione and total protein, there was no significant decrease in the levels of alkaline phosphatase (ALP) in exposed dental workers when compared with non-occupationally exposed individuals. CONCLUSIONS It is concluded that mercury vapor concentrations in the indoor air of some dental clinics in Baghdad city are high and exceed the OSHA STEL(Occupational Safety and Health Administration Short Term Exposure Limit). The present data showed that altered biochemical parameters can be used as efficient bioindicators for mercury toxicity.
Collapse
Affiliation(s)
| | - Adel Mashaan Rabee
- b Department of Biology, College of Science , University of Baghdad , Baghdad , Iraq
| |
Collapse
|
10
|
Shirkhanloo H, Fallah Mehrjerdi MA, Hassani H. Identifying occupational and nonoccupational exposure to mercury in dental personnel. ARCHIVES OF ENVIRONMENTAL & OCCUPATIONAL HEALTH 2017; 72:63-69. [PMID: 25257992 DOI: 10.1080/19338244.2014.964391] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/09/2014] [Accepted: 08/30/2014] [Indexed: 05/24/2023]
Abstract
The objective of this study was to investigate the occupational and nonoccupational exposure to mercury (Hg) vapor in dental personnel by examining the relationships between blood mercury, urine mercury, and their ratio with air mercury. The method was performed on 50 occupational exposed and 50 unexposed controls (25 men and 25 women). The mercury concentrations in air and human biological samples were determined based on the National Institute for Occupational Safety and Health (NIOSH) method and standard method (SM) by a new mode of liquid-phase microextraction, respectively. The mean mercury concentrations in urine (μg Hg0/g creatinine) and blood were significantly higher than control group, respectively (19.41 ± 5.18 vs 2.15 ± 0.07 μg/g and 16.40 ± 4.97 vs 2.50 ± 0.02 μg/L) (p <.001). The relationships between mercury concentration in blood/urine ratio (r = .380) with dental office air are new indicators for assessing occupational exposure in dental personnel.
Collapse
Affiliation(s)
- Hamid Shirkhanloo
- a Iranian Petroleum Industry Occupational and Environmental Health Research Center (IPIOEHRC), Iranian Petroleum Industry Health Research Institute (IPIHRI) , Tehran , Iran
| | | | - Hamid Hassani
- a Iranian Petroleum Industry Occupational and Environmental Health Research Center (IPIOEHRC), Iranian Petroleum Industry Health Research Institute (IPIHRI) , Tehran , Iran
- c Department of Occupational Health Engineering , School of Public Health, Tehran University of Medical Sciences , Tehran , Iran
| |
Collapse
|
11
|
Nagpal N, Bettiol SS, Isham A, Hoang H, Crocombe LA. A Review of Mercury Exposure and Health of Dental Personnel. Saf Health Work 2016; 8:1-10. [PMID: 28344835 PMCID: PMC5355537 DOI: 10.1016/j.shaw.2016.05.007] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/24/2016] [Revised: 05/18/2016] [Accepted: 05/30/2016] [Indexed: 11/02/2022] Open
Abstract
Considerable effort has been made to address the issue of occupational health and environmental exposure to mercury. This review reports on the current literature of mercury exposure and health impacts on dental personnel. Citations were searched using four comprehensive electronic databases for articles published between 2002 and 2015. All original articles that evaluated an association between the use of dental amalgam and occupational mercury exposure in dental personnel were included. Fifteen publications from nine different countries met the selection criteria. The design and quality of the studies showed significant variation, particularly in the choice of biomarkers as an indicator of mercury exposure. In several countries, dental personnel had higher mercury levels in biological fluids and tissues than in control groups; some work practices increased mercury exposure but the exposure levels remained below recommended guidelines. Dental personnel reported more health conditions, often involving the central nervous system, than the control groups. Clinical symptoms reported by dental professionals may be associated with low-level, long-term exposure to occupational mercury, but may also be due to the effects of aging, occupational overuse, and stress. It is important that dental personnel, researchers, and educators continue to encourage and monitor good work practices by dental professionals.
Collapse
Affiliation(s)
- Natasha Nagpal
- Oxford Brookes University, School of Psychology, Social Work and Public Health, Oxford, UK
| | - Silvana S Bettiol
- School of Medicine, University of Tasmania, Hobart, Tasmania, Australia
| | - Amy Isham
- University Department of Rural Health, University of Tasmania, Hobart, Tasmania, Australia
| | - Ha Hoang
- University Department of Rural Health, University of Tasmania, Hobart, Tasmania, Australia
| | - Leonard A Crocombe
- University Department of Rural Health, University of Tasmania, Hobart, Tasmania, Australia
| |
Collapse
|
12
|
Al-Saleh I, Nester M, Abduljabbar M, Al-Rouqi R, Eltabache C, Al-Rajudi T, Elkhatib R. Mercury (Hg) exposure and its effects on Saudi breastfed infant's neurodevelopment. Int J Hyg Environ Health 2016; 219:129-41. [DOI: 10.1016/j.ijheh.2015.10.002] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2015] [Revised: 10/18/2015] [Accepted: 10/19/2015] [Indexed: 10/22/2022]
|
13
|
|
14
|
Neghab M, Zare Derisi F, Hassanzadeh J. Respiratory symptoms and lung functional impairments associated with occupational exposure to asphalt fumes. THE INTERNATIONAL JOURNAL OF OCCUPATIONAL AND ENVIRONMENTAL MEDICINE 2015; 6:113-21. [PMID: 25890605 PMCID: PMC6977039 DOI: 10.15171/ijoem.2015.473] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Subscribe] [Scholar Register] [Received: 06/27/2014] [Accepted: 08/27/2014] [Indexed: 11/28/2022]
Abstract
Background: Controversy exists as to the potential of asphalt fumes to induce respiratory symptoms and lung functional impairments. Objective: To examine the respiratory effects, if any, of occupational inhalation exposure to asphalt fumes. Methods: In this cross-sectional study, 74 asphalt workers and 110 unexposed employees were investigated. The prevalence of respiratory symptoms among subjects was investigated by a standard questionnaire. Additionally, the parameters of pulmonary function were measured both, prior to exposure and at the end of work-shift. Furthermore, to assess the extent to which workers were exposed to asphalt fumes, total particulate and the benzene-soluble fraction were measured in different worksites. Results:
The mean levels of exposure to total particulate and benzene-soluble fraction in asphalt fumes were estimated to be 0.9 (SD 0.2) and 0.3 (SD 0.1) mg/m3, respectively. Mean values of FEV1, both prior to the exposure (89.58% [SD 18.69%] predicted value) and at the end of shift (85.38% [SD 19.4%]), were significantly (p<0.05) smaller than those of the comparison subjects (93.88% [SD 13.93%]). Similarly, pre-shift (87.05 [SD 8.57]) and postexposure (89.95 [SD 6.85]) FEV1/FVC ratio were both significantly (p<0.01) lower than those of the unexposed employees (107.56 [SD 9.64]). Moreover, the prevalence of respiratory symptoms such as cough and wheezing in exposed employees were 41% and 42%, respectively. The corresponding values for comparison subjects were 10.0% and 3.6%, respectively (p<0.001). The pattern of changes in parameters of lung function in asphalt workers was consistent with that of chronic obstructive lung disease.
Conclusion: Significant decrements in the parameters of pulmonary function as well as, a significant increase in the prevalence of respiratory symptoms in asphalt paving workers compared to their unexposed counterparts provided evidence in favor of a significant association between exposure to asphalt fumes and lung function impairments.
Collapse
Affiliation(s)
| | - F Zare Derisi
- Student Research Committee, School of Health, Shiraz University of Medical Sciences, Shiraz, Iran.
| | | |
Collapse
|
15
|
Anglen J, Gruninger SE, Chou HN, Weuve J, Turyk ME, Freels S, Stayner LT. Occupational mercury exposure in association with prevalence of multiple sclerosis and tremor among US dentists. J Am Dent Assoc 2015; 146:659-668.e1. [DOI: 10.1016/j.adaj.2015.05.016] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/20/2015] [Revised: 05/12/2015] [Accepted: 05/17/2015] [Indexed: 10/23/2022]
|
16
|
Early Liver and Kidney Dysfunction Associated with Occupational Exposure to Sub-Threshold Limit Value Levels of Benzene, Toluene, and Xylenes in Unleaded Petrol. Saf Health Work 2015; 6:312-6. [PMID: 26929843 PMCID: PMC4682028 DOI: 10.1016/j.shaw.2015.07.008] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/21/2015] [Revised: 06/29/2015] [Accepted: 07/21/2015] [Indexed: 12/04/2022] Open
Abstract
Background Unleaded petrol contains significant amounts of monocyclic aromatic hydrocarbons such as benzene, toluene, and xylenes (BTX). Toxic responses following occupational exposure to unleaded petrol have been evaluated only in limited studies. The main purpose of this study was to ascertain whether (or not) exposure to unleaded petrol, under normal working conditions, is associated with any hepatotoxic or nephrotoxic response. Methods This was a cross-sectional study in which 200 employees of Shiraz petrol stations with current exposure to unleaded petrol, as well as 200 unexposed employees, were investigated. Atmospheric concentrations of BTX were measured using standard methods. Additionally, urine and fasting blood samples were taken from individuals for urinalysis and routine biochemical tests of kidney and liver function. Results The geometric means of airborne concentrations of BTX were found to be 0.8 mg m−3, 1.4 mg m−3, and 2.8 mg m−3, respectively. Additionally, means of direct bilirubin, alanine aminotransferase, aspartate aminotransferase, blood urea and plasma creatinine were significantly higher in exposed individuals than in unexposed employees. Conversely, serum albumin, total protein, and serum concentrations of calcium and sodium were significantly lower in petrol station workers than in their unexposed counterparts. Conclusion The average exposure of petrol station workers to BTX did not exceed the current threshold limit values (TLVs) for these chemicals. However, evidence of subtle, subclinical and prepathologic early liver and kidney dysfunction was evident in exposed individuals.
Collapse
|
17
|
Gordan VV, Riley J, Geraldeli S, Williams OD, Spoto JC, Gilbert GH. The decision to repair or replace a defective restoration is affected by who placed the original restoration: findings from the National Dental PBRN. J Dent 2014; 42:1528-34. [PMID: 25223822 DOI: 10.1016/j.jdent.2014.09.005] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/04/2014] [Revised: 09/05/2014] [Accepted: 09/06/2014] [Indexed: 10/24/2022] Open
Abstract
OBJECTIVES To evaluate how restoration characteristics are associated with the decision to repair or replace an existing restoration. The following hypotheses were studied: dentists who placed the original restoration are more likely to repair instead of replace restorations (H1) that are in molar teeth; (H2) that are in the upper arch; (H3) that have amalgam restorative material; (H4) if a fracture is not the primary reason for the defect; and (H5) when the restoration comprises more than one surface. METHODS This cross-sectional study used a consecutive patient/restoration recruitment design. 194 dentists members of a dental practice-based research network recorded data on restorations in permanent teeth that needed repair or replacement. RESULTS For 6623 of the 8770 defective restorations in 6643 patients, the treatment was provided by the dentist who had not placed the original restoration (75%). The 2-way interaction revealed that dentists who had placed the original restoration often chose to repair when the defective restoration was in a molar, relative to premolar or anterior teeth (OR=2.2, p<.001); and chose to replace when the restoration had amalgam (OR=0.5, p<.001), and when it was a fracture compared to another reason (OR=0.8, p=001). CONCLUSION Most dentists are not conservative when they revisit a restoration that they originally placed regardless of type of failure, number of surfaces or material used. However, dentists who had placed the original restoration were significantly more likely to repair it when the defective restoration was in a molar tooth. CLINICAL SIGNIFICANCE Most dentists who placed the original restoration were prone to replace it, however if the defective restoration was located in a molar tooth they would consider repairing it.
Collapse
Affiliation(s)
- Valeria V Gordan
- Department of Restorative Dental Sciences, Division of Operative Dentistry, University of Florida, Gainesville, FL, United States.
| | - Joseph Riley
- Department of Community Dentistry and Behavioral Sciences, University of Florida, Gainesville, FL, United States
| | - Saulo Geraldeli
- Department of Restorative Dental Sciences, Division of Operative Dentistry, University of Florida, Gainesville, FL, United States
| | - O Dale Williams
- Department of Biostatistics, Florida International University, Miami, FL, United States
| | | | - Gregg H Gilbert
- Department of Clinical and Community Sciences, School of Dentistry, University of Alabama at Birmingham, Birmingham, AL, United States
| | | |
Collapse
|
18
|
Rafati-Rahimzadeh M, Rafati-Rahimzadeh M, Kazemi S, Moghadamnia AA. Current approaches of the management of mercury poisoning: need of the hour. ACTA ACUST UNITED AC 2014; 22:46. [PMID: 24888360 PMCID: PMC4055906 DOI: 10.1186/2008-2231-22-46] [Citation(s) in RCA: 55] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/03/2013] [Accepted: 05/14/2014] [Indexed: 12/31/2022]
Abstract
Mercury poisoning cases have been reported in many parts of the world, resulting in many deaths every year. Mercury compounds are classified in different chemical types such as elemental, inorganic and organic forms. Long term exposure to mercury compounds from different sources e.g. water, food, soil and air lead to toxic effects on cardiovascular, pulmonary, urinary, gastrointestinal, neurological systems and skin. Mercury level can be measured in plasma, urine, feces and hair samples. Urinary concentration is a good indicator of poisoning of elemental and inorganic mercury, but organic mercury (e.g. methyl mercury) can be detected easily in feces. Gold nanoparticles (AuNPs) are a rapid, cheap and sensitive method for detection of thymine bound mercuric ions. Silver nanoparticles are used as a sensitive detector of low concentration Hg2+ ions in homogeneous aqueous solutions. Besides supportive therapy, British anti lewisite, dimercaprol (BAL), 2,3-dimercaptosuccinic acid (DMSA. succimer) and dimercaptopropanesulfoxid acid (DMPS) are currently used as chelating agents in mercury poisoning. Natural biologic scavengers such as algae, azolla and other aquatic plants possess the ability to uptake mercury traces from the environment.
Collapse
Affiliation(s)
| | | | | | - Ali Akbar Moghadamnia
- Department of Pharmacology, Faculty of Medicine, Babol University of Medical Sciences, Babol, Iran.
| |
Collapse
|
19
|
Warwick R, O'Connor A, Lamey B. Mercury vapour exposure during dental student training in amalgam removal. J Occup Med Toxicol 2013; 8:27. [PMID: 24090056 PMCID: PMC3850894 DOI: 10.1186/1745-6673-8-27] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/05/2013] [Accepted: 09/16/2013] [Indexed: 11/26/2022] Open
Abstract
Background Amalgam that is used for dental fillings contains approximately 50% elemental mercury. During dental student training, amalgam is often removed by drilling without the use of water spray and suction, which are protective measures in preventing mercury aerosol. In this study we measured mercury vapor levels in ambient air during amalgam removal as is typically performed in dental training. Methods Mercury vapor levels in ambient air were measured in a dental school laboratory during removal of amalgam fillings from artificial teeth set into a dental jaw simulator. Mercury vapor was measured under three conditions (25 measurements each): with the simultaneous use of water spray and suction, with the use of suction only, and with the use of neither suction nor water spray. These three conditions are all used during dental student training. Results were compared to Alberta occupational exposure limits for mercury vapor in order to assess potential occupational risk to students. Analysis of variance testing was used to compare data obtained under the three conditions. Results When water spray and suction were used, mercury vapor levels ranged from 4.0 to 19.0 μg/m3 (arithmetic mean = 8.0 μg/m3); when suction only was used, mercury vapor levels ranged from 14.0 to 999.0 (999.0 μg/m3 represents the high limit detection of the Jerome analyzer) (arithmetic mean = 141.0 μg/m3); when neither suction nor water was used, the vapor levels ranged from 34.0 to 796.0 μg/m3 (arithmetic mean = 214.0 μg/m3). Conclusions The Alberta Occupational Health and Safety threshold limit value for mercury vapor over an eight-hour time-weighted period is 25.0 μg/m3. The absolute ceiling for mercury vapor, not to be exceeded at any time, is 125.0 μg/m3. When both water spray and suction were used, mercury vapor levels were consistently below this threshold. When suction without water spray was used, mercury vapor levels exceeded the safety threshold 8% of the time. When neither water spray nor suction was used, 36% of the mercury vapor readings exceeded the absolute ceiling value. To maximize safety, dental schools should train students to remove amalgam only while using water spray and high volume suction. Alternatively, students should use appropriate occupational hygiene personal protective equipment during amalgam removals.
Collapse
Affiliation(s)
- Robin Warwick
- Hanna Dental Clinic, 104 Fox Lake Trail, Hanna, Alberta, Canada.
| | | | | |
Collapse
|
20
|
Gordan VV. Translating research into everyday clinical practice: lessons learned from a USA dental practice-based research network. Dent Mater 2013; 29:3-9. [PMID: 22889478 PMCID: PMC3524332 DOI: 10.1016/j.dental.2012.07.159] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/24/2012] [Revised: 07/24/2012] [Accepted: 07/27/2012] [Indexed: 02/05/2023]
Abstract
OBJECTIVES This paper discusses practice-based research (PBR) as a means to speed up the translation of research findings to clinical practice. It also reviews repair versus replacement of defective restorations as one example of the delay in the application of research findings to clinical practice. METHODS Despite the existence of clinical studies, a significant delay exists between the generation of new knowledge and its application into the medical/dental community and their patients. One example is the repair of defective dental restorations. About 75% of practitioners in general dental practices do not consider the repair of dental restorations as a viable alternative to the replacement of defective restorations. Engaging and partnering with health practitioners in the field on studies addressing everyday clinical research questions may offer a solution to speed up the translation of the research findings. RESULTS Practice-based research (PBR) offers a unique opportunity for practitioners to be involved in the research process, formulating clinical research questions. Additionally, PBR generates evidence-based knowledge with a broader spectrum that can be more readily generalized to the public. With PBR, clinicians are involved in the entire research process from its inception to its dissemination. SIGNIFICANCE Early practitioner interaction in the research process may result in ideas being more readily incorporated into practice. Clinical studies are of paramount importance for testing and translation of the research findings to the community.
Collapse
Affiliation(s)
- Valeria V Gordan
- Department of Restorative Dental Sciences, University of Florida, Gainesville, FL, USA.
| |
Collapse
|
21
|
Gordan VV, Riley JL, Worley DC, Gilbert GH. Restorative material and other tooth-specific variables associated with the decision to repair or replace defective restorations: findings from The Dental PBRN. J Dent 2012; 40:397-405. [PMID: 22342563 DOI: 10.1016/j.jdent.2012.02.001] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/03/2011] [Revised: 02/01/2012] [Accepted: 02/01/2012] [Indexed: 02/07/2023] Open
Abstract
OBJECTIVES Using data from dentists participating in The Dental Practice-Based Research Network (DPBRN), the study had 2 main objectives: (1) to identify and quantify the types of restorative materials in the existing failed restorations; and (2) to identify and quantify the materials used to repair or replace those failed restorations. METHODS This cross-sectional study used a consecutive patient/restoration recruitment design. Practitioner-investigators recorded data on consecutive restorations in permanent teeth that needed repair or replacement. Data included the primary reason for repair or replacement, tooth surface(s) involved, restorative materials used, and patient demographics. RESULTS Data for 9875 restorations were collected from 7502 patients in 197 practices for which 75% of restorations were replaced and 25% repaired. Most of the restorations that were either repaired or replaced were amalgam (56%) for which most (56%) of the material used was direct tooth-coloured. The restorative material was 5 times more likely to be changed when the original restoration was amalgam (OR=5.2, p<.001). The likelihood of changing an amalgam restoration differed as a function of the tooth type (OR=3.0, p<.001), arch (OR=6.6, p<.001); and number of surfaces in the original restoration (OR=12.2, p<.001). CONCLUSION The probability of changing from amalgam to another restorative material differed with several characteristics of the original restoration. The change was most likely to take place when (1) the treatment was a replacement; (2) the tooth was not a molar; (3) the tooth was in the maxillary arch; and (4) the original restoration involved a single surface.
Collapse
Affiliation(s)
- Valeria V Gordan
- Department of Restorative Dental Sciences, Operative Dentistry Division, University of Florida, College of Dentistry, Gainesville, FL 32610-0415, USA.
| | | | | | | | | |
Collapse
|