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Objective: To explore the composition characteristics of atmospheric fine particulate matter (PM2.5) and bronchoalveolar lavage fluid (BALF), and their impact on the development of chronic obstructive pulmonary disease (COPD)., Methods: The atmospheric PM2.5 samples and BALF samples from COPD patients were collected from June 2, 2017 to October 30, 2018, and allocated into a high-risk of PM2.5 inhalation group and a low-risk PM2.5 inhalation group according to the heating season in Harbin. Inorganic elements were detected by ICP-MS, and polycyclic aromatic hydrocarbons (PAHs) were detected by GC/MS., Results: Twenty-six inorganic elements were found in 54 BALF specimens. There was a high correspondence in inorganic elements between BALF and atmospheric PM2.5. Trace elements Cr, Mn, V, and Co, and toxic trace elements Al, Pb, Cd, As, and Ag were above the upper limit of normal blood. There were significant higher K, Ti, Fe, Co, Cu, Se, Rb, Ag, and Sb in BALF of the high-risk PM2.5 inhalation group (p < 0.05). Sixteen PAHs were detected in 32 BALF samples. The main components of BALF and atmospheric PM2.5 were the high molecular weight PAHs, and the species and concentration of PAHs in BALF and atmospheric PM2.5 are highly consistent., Conclusion: The types and concentrations of inorganic elements and PAHs in BALF of COPD patients are highly consistent with those of atmospheric PM2.5. The sustained high concentrations of Benzo(a)anthracene, Chrysene, Benzo(b)Fluoranthene, Benzo(k)Fluoranthene, Indeno(123-c,d)Pyrene, and Benzo(a)Pyrene in BALF of COPD patients may have long-term adverse effects on COPD patients., (Copyright © 2020 Elsevier Ltd. All rights reserved.)

Background: Risk factors operating independently of hyperuricemia could be of importance in determining why only a minority of people with hyperuricemia develop gout. Exposure to inorganic dust has been linked to other inflammatory diseases and could influence the development of gout., Objectives: To evaluate if occupational exposure to inorganic dust increases the risk of gout., Methods: Individuals aged 30-65 years with a first gout diagnosis in 2006-2012 in the population-based healthcare database of the Western Swedish Healthcare Region (VEGA) and population controls matched by age and sex were included. Data on occupation was collected from the Swedish occupational register. Exposure status was assigned by means of a job exposure matrix. Data on gout-related comorbidities was collected from VEGA. Alcohol use disorder and obesity were related both to gout and exposure to inorganic dust and were adjusted for in multivariate analyses. ORs were calculated using conditional logistic regression., Results: 5042 gout cases and 20 682 controls were included. Exposure to inorganic dust was associated with gout in both unadjusted (OR 1.12, 95% CI 1.04 to 1.20) and multivariate (OR 1.08, 95% CI 1.00 to 1.16) analyses of the whole population. In sex-stratified multivariate analyses, dust exposure was significantly associated with gout in women (adjusted OR 1.26, 95% CI 1.05 to 1.51), but not in men (adjusted OR 1.05, 95% CI 0.97 to 1.13)., Conclusions: We describe for the first time an association between exposure to inorganic dust and gout. After adjusting for confounders, the findings were statistically significant for women but not for men., Competing Interests: Competing interests: None declared., (© Author(s) (or their employer(s)) 2020. Re-use permitted under CC BY-NC. No commercial re-use. See rights and permissions. Published by BMJ.)

UV radiation exposure is the major contributor to photocarcinogenesis and photoageing. Reducing UV radiation exposure can be achieved by using adequate sunscreen preparations. The use of sunscreen can significantly reduce the incidence of squamous cell carcinoma, actinic keratoses and invasive melanoma. In the Australian market over 900 sunscreen products are available, each with their own brand, formulation and ingredients. It can be difficult for dermatologists and consumers to determine which are the most effective and appropriate products to use. We discuss the specific active ingredients found in sunscreen formulations available in Australia, their mode of protection, photostability, solubility, and side-effects and the methods used by the Therapeutic Goods Administration to determine the ratings and efficacy of each sunscreen., (© 2017 The Australasian College of Dermatologists.)

In order to design effective strategies to reduce the public health burden of ambient fine particulate matter (PM 2.5 ) imposed in an area, it is necessary to identify the emissions sources affecting that location and quantify their contributions. However, it is challenging because PM 2.5 travels long distances and most constituents are the result of complex chemical processes. We developed a reduced-form source-receptor model for estimating locations and magnitudes of downwind health costs from a source or, conversely, the upwind sources that contribute to health costs at a receptor location. Built upon outputs from a state-of-the-art air quality model, our model produces comprehensive risk-based source apportionment results with trivial computational costs. Using the model, we analyzed all the sources contributing to the inorganic PM 2.5 health burden in 14 metropolitan statistical areas (MSAs) in the United States. Our analysis for 12 source categories shows that 80-90% of the burden borne by these areas originates from emissions sources outside of the area and that emissions sources up to 800 km away need to be included to account for 80% of the burden. Conversely, 60-80% of the impacts of an MSA's emissions occurs outside of that MSA. The results demonstrate the importance of regionally coordinated measures to improve air quality in metropolitan areas., (Copyright © 2017. Published by Elsevier Ltd.)

Objectives: Occupational exposure to the composite measure vapours, gases, dusts and fumes (VGDF), contribute to the burden of asthma and rhinitis. The objective was to evaluate occupational exposure to VGDF, which is further divided into the components chemicals, organic and inorganic dust in relation to asthma and rhinitis., Methods: Previously examined participants from three population-based cohorts in the Obstructive Lung disease In Northern Sweden (OLIN) studies were re-examined during 2002-2004. In total, 4036 participated in a structured interview and answered a questionnaire on occupational exposures., Results: Occupational exposure to VGDF increased the risk of asthma, and concomitant asthma and rhinitis. Exposure to chemicals, but not dust, showed a similar pattern. Exposure to chemicals increased the risks (OR, 95% CI) of rhinitis without asthma (1.29, 1.10 to 1.52), asthma without rhinitis (1.42, 1.15 to 1.77) and concomitant asthma and rhinitis (1.60, 1.31 to 1.96) when adjusted for confounders such as age, smoking habits, body mass index and sex. The association between exposure to chemicals and asthma and rhinitis remained independent of exposure to dust and was also so when excluding exposure to isocyanates and welding fumes. The results were similar for women and men, as well as for never-smokers and participants without a history of allergy., Conclusions: In this cross-sectional population-based study, occupational exposure to chemicals contributed substantially to the increased risk of asthma and rhinitis observed for occupational exposure to VGDF., (Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/)

Chemical flocculants are generally used in drinking water and wastewater treatment due to their efficacy and cost effectiveness. However, the question of their toxicity to human health and environmental pollution has been a major concern. In this article, we review the application of some chemical flocculants utilized in water treatment, and bioflocculants as a potential alternative to these chemical flocculants. To the best of our knowledge, there is no report in the literature that provides an up-to-date review of the relevant literature on both chemical flocculants and bioflocculants in one paper. As a result, this review paper comprehensively discussed the various chemical flocculants used in water treatment, including their advantages and disadvantages. It also gave insights into bioflocculants production, challenges, various factors influencing their flocculating efficiency and their industrial applications, as well as future research directions including improvement of bioflocculants yields and flocculating activity, and production of cation-independent bioflocculants. The molecular biology and synthesis of bioflocculants are also discussed., (© 2016 The Authors. MicrobiologyOpen published by John Wiley & Sons Ltd.)

Although nanoparticles research is ongoing since more than 30years, the development of methods and standard protocols required for their safety and efficacy testing for human use is still in development. The review covers questions on toxicity, safety, risk and legal issues over the lifecycle of inorganic nanoparticles for medical applications. The following topics were covered: (i) In vitro tests may give only a very first indication of possible toxicity as in the actual methods interactions at systemic level are mainly neglected; (ii) the science-driven and the regulation-driven approaches do not really fit for decisive strategies whether or not a nanoparticle should be further developed and may receive a kind of "safety label". (iii) Cost and time of development are the limiting factors for the drug pipeline. Knowing which property of a nanoparticle makes it toxic it may be feasible to re-engineer the particle for higher safety (safety by design)., From the Clinical Editor: Testing the safety and efficacy of nanoparticles for human use is still in need of standardization. In this concise review, the author described and discussed the current unresolved issues over the application of inorganic nanoparticles for medical applications., (Copyright © 2015 Elsevier Inc. All rights reserved.)

In the presented review there is discussed the dynamics of diseases of the endocrine system of the population, including diabetes and thyroid pathology and the modern view on the importance of chemical factors (pesticides, arsenic, essential and toxic elements) for their formation.

Background: Several occupations and occupational exposures have been investigated for associations with Parkinson's disease. Common findings are increased risk associated with pesticide exposure and no association between Parkinson's disease and welding., Methods: We explored the association between a broad range of possible occupational risk factors and Parkinson's disease as well as Parkinson's disease plus other forms of Parkinsonism (referred to as Parkinsonian disorders), using prospectively collected data in the population-based Swedish Twin Registry. A cohort of 14,169 Swedish men was followed for up to 43 years. We identified 234 Parkinsonian disorder cases including 204 Parkinson's disease cases with complete data. We assessed exposure to 14 chemical and biological compounds through a job exposure matrix. Hazard ratios (HR) with 95% confidence intervals (CI) adjusted for age, smoking, and education were used to estimate the relative risk of disease associated with exposure., Results: Exposure to inorganic dust was associated with increased risk of Parkinson's disease and Parkinsonian disorders, HR 1.6 (95% CI 1.1-2.4) and 1.5 (1.0-2.2) respectively. There was no association between Parkinson's disease or Parkinsonian disorders and occupational exposure to pesticides, welding smoke, metal dust, wood dust, animal handling, stone and concrete dust, chrome and nickel dust, quartz dust, organic dust, oil, asbestos, organic solvents and irritating gas., Conclusions: Inorganic dust should be explored further as a potential risk factor for Parkinson's disease. Occupational exposure to pesticides and twelve other compounds explored in this study may not be associated with risk of Parkinson's disease in Swedish men., (Copyright © 2011 Elsevier Ltd. All rights reserved.)

This paper reports the content in macronutrients, free sugars, polyphenols, and inorganic ions, known to exert any positive or negative action on microbial oral disease such as caries and gingivitis, of seven food/beverages (red chicory, mushroom, raspberry, green and black tea, cranberry juice, dark beer). Tea leaves resulted the richest material in all the detected ions, anyway tea beverages resulted the richest just in fluoride. The highest content in zinc was in chicory, raspberry and mushroom. Raspberry is the richest food in strontium and boron, beer in selenium, raspberry and mushroom in copper. Beer, cranberry juice and, especially green and black tea are very rich in polyphenols, confirming these beverages as important sources of such healthy substances. The fractionation, carried out on the basis of the molecular mass (MM), of the water soluble components occurring in raspberry, chicory, and mushroom extracts (which in microbiological assays revealed the highest potential action against oral pathogens), showed that both the high and low MM fractions are active, with the low MM fractions displaying the highest potential action for all the fractionated extracts. Our findings show that more compounds that can play a different active role occur in these foods.

Secondary organ absorbed doses were calculated by Monte Carlo simulations with the SHIELD-HIT07 code coupled with the mathematical anthropomorphic phantoms CHILD-HIT and ADAM-HIT. The simulated irradiations were performed with primary (1)H, (4)He, (7)Li, (12)C and (16)O ion beams in the energy range 100-400 MeV/u which were directly impinging on the phantoms, i.e. approximating scanned beams, and with a simplified beamline for (12)C irradiation. The evaluated absorbed doses to the out-of-field organs were in the range 10(-6) to 10(-1) mGy per target Gy and with standard deviations 0.5-20%. While the contribution to the organ absorbed doses from secondary neutrons dominated in the ion beams of low atomic number Z, the produced charged fragments and their subsequent charged secondaries of higher generations became increasingly important for the secondary dose delivery as Z of the primary ions increased. As compared to the simulated scanned (12)C ion beam, the implementation of a simplified beamline for prostate irradiation with (12)C ions resulted in an increase of 2-50 times in the organ absorbed doses depending on the distance from the target volume. Comparison of secondary organ absorbed doses delivered by (1)H and (12)C beams showed smaller differences when the RBE for local tumor control of the ions was considered and normalization to the RBE-weighted dose to the target was performed.

The cosmetic industry is among the first adaptors of nanotechnology through the use of engineered nanoparticles (ENPs) to enhance the performance of their products and meet the customers' needs. Recently, there have been increasing concerns from different societal stakeholders (e.g., governments, environmental activist pressure groups, scientists, general public, etc.) concerning the safety and environmental impact of ENPs used in cosmetics. This review paper seeks to address the twin concerns of the safety of cosmetics and the potential environmental impacts due to the constituent chemicals-the ENPs. The safety aspect is addressed by examining recently published scientific data on the possibility of ENPs penetrating human skin. Data indicates that although particular types of ENPs can penetrate into the skin, until now no penetration has been detected beyond the stratum corneum of the ENPs used in cosmetics. Yet, important lessons can be learned from the more recent studies that identify the characteristics of ENPs penetrating into and permeating through human skin. On the part of the environmental impact, the scientific literature has very limited or none existent specific articles addressing the environmental impacts of ENPs owing to the cosmetic products. Therefore, general ecotoxicological data on risk assessment of ENPs has been applied to ascertain if there are potential environmental impacts from cosmetics. Results include some of the first studies on the qualitative and quantitative risk assessment of ENPs from cosmetics and suggest that further research is required as the knowledge is incomplete to make definitive conclusions as is the case with skin penetration. The authors conclude that the cosmetic industry should be more transparent in its use of nanotechnology in cosmetic products to facilitate realistic risk assessments as well as scientists and pressure groups being accurate in their conclusions on the general applicability of their findings. Transparency in cosmetics needs nanotechnology, but nanotechnology in cosmetics also needs transparency...

Subject matter experts systematically reviewed evidence on the effectiveness of housing interventions that affect health outcomes associated with exposure to chemical agents, such as pesticides, lead, volatile organic compounds, as well as the radon gas. Particulates were also examined, and the role of ventilation on exposures was assessed. The review included both published literature and peer-reviewed reports from the US Environmental Protection Agency. Four of the 14 interventions reviewed had sufficient evidence to demonstrate their effectiveness and are ready for implementation: radon air mitigation by using active soil depressurization systems, integrated pest management to reduce exposures to pesticides, smoke-free home policies making indoor areas smoke-free (ie, no smoking allowed anywhere at any time), and residential lead hazard control. Four interventions needed more field evaluation, 3 needed formative research, and 3 either had no sufficient evidence of effectiveness or had evidence the interventions were ineffective. This evidence review shows that housing improvements are likely to help reduce radon-induced lung cancer, cardiovascular mortality related to secondhand smoke, and neurological effects from exposure to pesticides and lead paint. Investing in housing interventions may yield important savings from reduced disease and injury from avoidable exposures to chemical agents.

This paper briefly outlines the United Nations Globally Harmonized System of Classification and Labelling of Chemicals (GHS) and what is meant by GHS implementation in terms of policy-related information for decision-makers plus a framework of actions to enable such policies to be effectively undertaken. The paper discusses the need for simple indicators to measure progress with GHS implementation. Two groups of indicators have been described that comprehensively reflect basic components of GHS implementation. The first group was presented as aggregated indicators or indices, for national capability evaluation. Indicators to evaluate management performance linked to stated objectives were presented as the second group. Information from an Organisation for Economic Co-operation and Development (OECD) published questionnaire on GHS implementation and a questionnaire by the Intergovernmental Forum on Chemical Safety (IFCS) on chemical safety that included GHS have provided the basic information for applying the management capability indicators approach. Through the use of information in these two questionnaires, country-relevant and regional progress with GHS implementation was illustrated. Despite the GHS implementation target of 2008 set by the Johannesburg Plan of Implementation, very few countries have reported they have achieved this target. The simple management indicators proposed in this paper are based on adoption of a questionnaire and a numerical scoring system that could be used to chart progress towards GHS implementation. It was concluded, therefore, that the use of indicators as described in this paper does provide a quick survey of the overall situation in a country and facilitates comparison between countries across regions in terms of GHS implementation. Furthermore such results may indicate which countries require additional assistance with GHS implementation thus strengthening policies and actions across all sectors and involving governments, business, trade, and civil society., (Copyright 2010 Elsevier Ltd. All rights reserved.)

Public concerns regarding exposures to synthetic chemicals are increasing. Globally, there are increasing concentrations of many synthetic chemicals within the environment. The ubiquitous extent of some chemicals makes human exposure unavoidable. Biomonitoring has emerged as the optimal method for assessing exposures. The extent of human exposure and contamination occurs throughout the life cycle and is widespread. Although there is limited information on health risks for the majority of chemicals within our environment, and those identified with biomonitoring, many are known or suspected to cause human harm. Continued global and national unsustainable development regarding synthetic chemicals will increase the extent of environmental and human contamination unless precautionary action is implemented. Precautionary legislation may protect ecological and public health until societal sustainability is achieved.

The Occupational Medicine Forum is prepared by the ACOEM Occupational and Environmental Medical Practice Committee and does not necessarily represent an official ACOEM position. The Forum is intended for health professionals and is not intended to provide medical or legal advice, including illness prevention, diagnosis or treatment, or regulatory compliance. Such advice should be obtained directly from a physician and/or attorney. Inquiries and contributions to the Forum should be forwarded to Joseph J. Schwerha, MD, MPH by e-mail at schwer@pitt.edu.

In this paper we report a successful application of machine learning approaches to the prediction of chemical carcinogenicity. Two different approaches, namely a support vector machine (SVM) and artificial neural network (ANN), were evaluated for predicting chemical carcinogenicity from molecular structure descriptors. A diverse set of 844 compounds, including 600 carcinogenic (CG+) and 244 noncarcinogenic (CG-) molecules, was used to estimate the accuracies of these approaches. The database was divided into two sets: the model construction set and the independent test set. Relevant molecular descriptors were selected by a hybrid feature selection method combining Fischer's score and Monte Carlo simulated annealing from a wide set of molecular descriptors, including physiochemical properties, constitutional, topological, and geometrical descriptors. The first model validation method was based a five-fold cross-validation method, in which the model construction set is split into five subsets. The five-fold cross-validation was used to select descriptors and optimise the model parameters by maximising the averaged overall accuracy. The final SVM model gave an averaged prediction accuracy of 90.7% for CG+ compounds, 81.6% for CG- compounds and 88.1% for the overall accuracy, while the corresponding ANN model provided an averaged prediction accuracy of 86.1% for CG+ compounds, 79.3% for CG- compounds and 84.2% for the overall accuracy. These results indicate that the hybrid feature selection method is very efficient and the selected descriptors are truly relevant to the carcinogenicity of compounds. Another model validation method, i.e. a hold-out method, was used to build the classification model using the selected descriptors and the optimised model parameters, in which the whole model construction set was used to build the classification model and the independent test set was used to test the predictive ability of the model. The SVM model gave a prediction accuracy of 87.6% for CG+ compounds, 79.1% for CG- compounds and 85.0% for the overall accuracy. The ANN model gave a prediction accuracy of 85.6% for CG+ compounds, 79.1% for CG- compounds and 83.6% for the overall accuracy. The results indicate that the built models are potentially useful for facilitating the prediction of chemical carcinogenicity of untested compounds.

In past decades, much attention has focused on the potential of inorganic nanoparticles as drug or gene delivery carriers due to their high cellular uptake capacity, non immunogenic response, and low toxicity. Layered double hydroxide (LDH), so-called anionic clay, is one of the most promising candidates for various biological purposes. Our previous report demonstrated that LDH had no significant cytotoxic effects at the concentration level of practical usage in human cell lines as well as in red blood cells. In this study, the optimum size of LDH nanoparticles was determined based on their toxicity in vitro and in vivo. Size-dependent toxicity of LDH was examined in cultured human lung cells; 50 nm particles were determined to be more toxic than larger particles, while LDHs within the size range of 100 to 200 nm exhibited very low cytotoxicity in terms of cell proliferation, membrane damage, and inflammation response. In animal model, all different-sized LDHs did not cause any mortality or body weight loss up to 600 mg/kg. Therefore, LDH is an attractive biocompatible delivery carrier for biological and medical applications.

The number of new chemicals synthesized and marketed increases exponentially. The database CAS REGISTRY at present contains more than 33 million organic and inorganic substances. However, the little information regarding the potential hazard associated with a large amount of chemicals is an old known problem in the European Union and also in the United States. This critical problem may find a solution in the collaboration of the different involved countries and in a planned task setting at international level. Both in the United States (e.g., the "Gore Initiative") and in European Union (the REACH policy) a big effort has been dedicated to this solution, within standardized procedures and an appropriate collaboration.

Ambient air particulate matter (PM) originates as either primary particles emitted directly into the atmosphere from a specific source or as secondary particles produced from atmospheric chemical reactions between precursor gases or between these gases and primary particles. PM can derive from both natural and anthropogenic sources, resulting in a complex chemical mix. The "fine" size mode of ambient PM, designated as PM(2.5), is defined as comprising those particles having aerodynamic diameters below 2.5 microm. While the total mass of PM(2.5) has been associated with adverse human health outcomes, the relationship between these and specific chemical components has not been resolved. This article provides a perspective on the current state of the science concerning health effects from a major group of chemical species found within PM(2.5), namely common inorganic constituents. The specific chemical classes discussed herein are secondary inorganic species, namely, sulfate, nitrate, and acidity, and generally crustal-derived species, namely, phosphate, sodium, potassium, calcium, magnesium, silicon, and aluminum. The article discusses evidence for adverse health effects from inorganic PM(2.5) components within the framework of various caveats surrounding both epidemiology and toxicology assessments. The largest database exists for sulfate, but conclusions that attribute sulfate to health outcomes have not been consistent across all epidemiology studies, and there is a lack of coherence with toxicology studies, which show biological responses only at high levels of exposure. Limited epidemiological and toxicological data for nitrate suggests little or no adverse health effects at current levels. Epidemiological studies specifically identifying crustal components of PM(2.5) suggest that they are not likely, by themselves, to produce a significant health risk, and these components do not have unequivocal biological plausibility from toxicological studies for being significant contributors to adverse health outcomes.

Exposure to inorganic particles may induce fibrosis in the lung. However, the association between exposure to inorganic particles and the pathogenesis of idiopathic pulmonary fibrosis (IPF)/usual interstitial pneumonia (UIP) is obscure. We examined inorganic particles in the pulmonary hilar lymph nodes affected by IPF/UIP to investigate whether inhaled elements are involved in the etiology, and whether there is an increasing risk of developing IPF/UIP. Twenty-three IPF/UIP cases and 23 controls without IPF/UIP were investigated. Pulmonary hilar lymph nodes constituted the study material. The elemental analysis was performed using scanning electron microscopy with an energy dispersive X-ray spectroscope, and we analyzed particles quantitatively and qualitatively. The results showed that the cases contained silicon and aluminum as compared with the control in lymph nodes, and these deposits were statistically significantly associated with an increased risk of IPF/UIP (adjusted odds were 2.99, 95% CI: 1.29-6.85 and 57.84, 95% CI: 1.45-2306.19, respectively). In addition, higher nickel levels in lymph nodes were associated with lung cancer. This study shows that inorganic particles, such as Si and Al, have higher concentrations in the hilar lymph nodes in IPF/UIP, and may play a role in one of the risk factors in the pathogenesis of IPF/UIP.

As early as the 19th century, research was being conducted on the passage of foreign material across the placenta from mother to offspring. The evidence resulting from these studies, while not always conclusive, should have prompted 20th century pharmaceutical companies to test new drugs for teratogenic activity if they were to be prescribed to women who were likely to become pregnant. The author concludes that if such investigations had been introduced, we may have avoided the thalidomide tragedy.

Indoor air pollution is ubiquitous, and takes many forms, ranging from smoke emitted from solid fuel combustion, especially in households in developing countries, to complex mixtures of volatile and semi-volatile organic compounds present in modern buildings. This paper reviews sources of, and health risks associated with, various indoor chemical pollutants, from a historical and global perspective. Health effects are presented for individual compounds or pollutant mixtures based on real-world exposure situations. Health risks from indoor air pollution are likely to be greatest in cities in developing countries, especially where risks associated with solid fuel combustion coincide with risk associated with modern buildings. Everyday exposure to multiple chemicals, most of which are present indoors, may contribute to increasing prevalence of asthma, autism, childhood cancer, medically unexplained symptoms, and perhaps other illnesses. Given that tobacco consumption and synthetic chemical usage will not be declining at least in the near future, concerns about indoor air pollution may be expected to remain.

The objective of our study was to investigate the possible interactive effect of occupational exposure to extremely low-frequency magnetic field (ELFMF) and to known or suspected carcinogenic chemicals on the incidence of the two main histological types of brain cancer, gliomas and meningiomas, in a cohort of male Swedish workers. The historical cohort of all Swedish men gainfully employed in 1970 were followed 19 years (1971-1989). Exposure to ELFMF and to nine chemicals were assessed using two Swedish job exposure matrices based on occupational codes and industrial activity. Relative risks adjusted for age, period, geographical area, and town size were computed using log-linear Poisson models. The main finding was the absence of ELFMF effect on glioma risk in the absence of a simultaneous exposure to chemical products. The effect of petroleum products was independent of the intensity of ELFMF exposure whereas solvents, lead, and pesticides/herbicides were only associated with glioma in workers also exposed to moderate or high levels of ELFMF. On the other hand, whereas ELFMF seemed to enhance the effect of specific chemicals in the causation of gliomas, we did not find a relationship between ELFMF exposure and meningiomas. The potential for ELFMF to act as an effect modifier of the association of chemical agents and glioma is an interesting new finding. It would be worthwhile to evaluate this hypothesis for other tumors. Also, it is necessary to confirm these results in epidemiological studies with individual exposure assessments, and in experimental studies that may elucidate whether there is a true causal mechanism for the results we observed.

Background: Occupational exposures may be related to the development of brain cancer. The objective was to estimate occupational-specific risk of gliomas and meningiomas among Swedish men and women gainfully employed in 1970 over the period 1971-1989, and the influence of occupational exposure to chemical substances., Methods: A dataset linking cancer diagnoses from the Swedish national cancer register to occupational and demographical data obtained in the 1970 census was used to fit log-linear Poisson models, in order to obtain relative risks adjusted by age, period, geographical area and town size. Exposure to 13 chemicals was assessed using a Swedish job-exposure matrix., Results: The main findings of this study among men were the increased risk of glioma with occupational exposure to arsenic, mercury, and petroleum products and of meningioma with lead. Women in occupational sectors with a higher socio-economic status showed an increased incidence of both, gliomas and meningiomas., Conclusions: Occupational exposure to some chemicals appeared to be related with an increased risk of glioma and meningioma in men. Exposures involved in glioma and meningioma development seemed to be different., (Copyright 2002 Wiley-Liss, Inc.)

This study assesses the effect of occupational exposure to specific chemicals on the risk of renal cell carcinoma in Canada. Mailed questionnaires were used to obtain data on 1279 (691 male and 588 female) newly diagnosed, histologically confirmed renal cell carcinoma cases and 5370 population controls in eight Canadian provinces, between 1994 and 1997. Data were collected on socio-economic status, smoking habit, alcohol use, diet, residential and occupational histories, and years of exposure to any of 17 chemicals. Odds ratios (ORs) and 95% confidence intervals (CIs) were derived using unconditional logistic regression. The study found an increased risk of renal cell carcinoma in males only, which was associated with occupational exposure to benzene; benzidine; coal tar, soot, pitch, creosote or asphalt; herbicides; mineral, cutting or lubricating oil; mustard gas; pesticides; and vinyl chloride. Compared with no exposure to the specific chemical, the adjusted ORs were 1.8 (95% CI = 1.2-2.6), 2.1 (1.3-3.6), 1.4 (1.1-1.8), 1.6 (1.3-2.0), 1.3 (1.1-1.7), 4.6 (1.7-12.5), 1.8 (1.4-2.3) and 2.0 (1.2-3.3), respectively; an elevated risk was also associated with exposure to cadmium salts and isopropyl oil. The risk of renal cell carcinoma increased with duration of exposure to benzene, benzidine, cadmium, herbicides and vinyl chloride. Very few females were exposed to specific chemicals in this study; further research is needed to clarify the association between occupational exposure to chemicals and renal cell carcinoma in females.

Objective: The objective of this review is to provide current approaches to gain increased understanding of the molecular basis of chemical allergenicity. Chemical allergy refers to an allergic reaction to a low molecular weight agent (ie, <1 kD). The symptoms and pathology of chemical asthma resemble those of allergy to larger sized agents, such as pollens, weeds, and danders. The differences relate to mechanisms of disease. To stimulate an immune response, low molecular weight chemicals function as haptens and bind to carrier macromolecules. This article focuses on the chemical reactions and physicochemical characteristics of chemical allergens., Data Sources: Data were obtained from published clinical reports and from the Documentation of Threshold Limit Values (1998) published by the American Congress of Governmental Industrial Hygienists., Results: In vitro studies indicate the stoichiometric reaction of some chemical allergens with glutathione and the subsequent transfer of the allergen from glutathione to other nucleophiles. Computer-generated structure-activity relationship models have been developed for chemicals that induce respiratory allergy. The models, based on physicochemical properties of the agents, have high sensitivity and specificity., Conclusions: The structure-activity relationship model suggests that chemical binding is the essential feature of chemical allergens. Their in vivo reactions with thiols may result in glutathione deficiency with consequent alteration in cellular reduction-oxidation (redox) status, release of cytokines, and promotion of the T helper cell 2 phenotype. Prevention of permanent disease is dependent on periodic medical surveillance of affected workers. When detected early, the disease can frequently be reversed.

Most studies of respiratory disease from dust exposure in the agricultural workplace have focused on allergic diseases caused by inorganic dusts, specifically occupational asthma and hypersensitivity pneumonitis. Exposures to inorganic (mineral) dusts among farmers and farm workers may be substantial. Such exposures are most frequent in dry-climate farming regions. In such locations farming activities that perturb the soil (e.g., plowing, tilling) commonly result in exposures to farm operators of 1-5 mg/m(3) respirable dust and >= 20 mg/m(3) total dust. The composition of inorganic dust in agriculture generally reflects the soil composition. Crystalline silica may represent up to 20% of particles, and silicates represent up to 80%. These very high concentrations of inorganic dust are likely to explain some of the increase in chronic bronchitis reported in many studies of farmers. Pulmonary fibrosis (mixed dust pneumoconiosis) has been reported in agricultural workers, and dust samples from the lungs in these cases reflect the composition of agricultural soils, strongly suggesting an etiologic role for inorganic agricultural dusts. However, the prevalence and clinical severity of these cases are unknown, and many exposures are to mixed organic and inorganic dusts. Epidemiologic studies of farmers in diverse geographic settings also have observed an increase in chronic obstructive pulmonary disease morbidity and mortality. It is plausible that agricultural exposure to inorganic dusts is causally associated with chronic bronchitis, interstitial fibrosis, and chronic obstructive pulmonary disease, but the independent contribution of mineral dusts beyond the effects of organic dusts remains to be determined.

In recent years the greatest progress in our understanding of pneumoconioses, other than those produced by asbestos, silica, and coal, has been in the arena of metal-induced parenchymal lung disorders. Inhalation of metal dusts and fumes can induce a wide range of lung pathology, including airways disorders, cancer, and parenchymal diseases. The emphasis of this update is on parenchymal diseases caused by metal inhalation, including granulomatous disease, giant cell interstitial pneumonitis, chemical pneumonitis, and interstitial fibrosis, among others. The clinical characteristics, epidemiology, and pathogenesis of disorders arising from exposure to aluminum, beryllium, cadmium, cobalt, copper, iron, mercury, and nickel are presented in detail. Metal fume fever, an inhalation fever syndrome attributed to exposure to a number of metals, is also discussed. Advances in our knowledge of antigen-specific immunologic reactions in the lung are particularly evident in disorders secondary to beryllium and nickel exposure, where immunologic mechanisms have been well characterized. For example, current evidence suggests that beryllium acts as an antigen, or hapten, and is presented by antigen-presenting cells to CD4+ T cells, which possess specific surface antigen receptors. Other metals such as cadmium and mercury induce nonspecific damage, probably by initiating production of reactive oxygen species. Additionally, genetic susceptibility markers associated with increased risk have been identified in some metal-related diseases such as chronic beryllium disease and hard metal disease. Future research needs include development of biologic markers of metal-induced immunologic disease, detailed characterization of human exposure, examination of gene alleles that might confer risk, and association of exposure data with that of genetic susceptibility.

It is important to understand a medical testís performance characteristics, so that it can be used appropriately. Performance characteristics of tests for antibodies specific to low-molecular-weight (LMW) agents in predicting asthma caused by these agents differ in the study population. In general, currently published data supporting the use of tests to detect specific IgE and IgG to LMW agents in the diagnosis of occupational asthma is limited and inconclusive. However, a few general statements can be made. The most promising results have been achieved for agents such as acid anhydrides and platinum salts, where specific IgE responses appear to play a significant pathogenic role in causing occupational asthma. Results have been less promising for agents such as isocyanates and plicatic acid, for which antibody responses do not appear to underlie the development of asthma in most individuals. In the case of isocyanates, determination of antigen-specific IgG might have some utility as a biomarker of exposure.

The chemical structure of low-molecular-weight substances (LMW) that cause occupational asthma (OA) determines their reactivity and hence their OA hazard. LMW agents that can form at least two bonds with native human macromolecules carry a higher OA hazard. Thus bi- or polyfunctional LMW agents such as diisocyanates and aliphatic or cyclic amines, as well as dicarboxylic acid anhydrides and dialdehydes, rank highly among organic LMW substances, while some transition metal ions or their complexes also are OA hazards. More subtle effects arise from diverse reactive groups or unsaturation. Quantitative structure activity relationships show increasing promise in predicting the OA hazard of these LMW substances.