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Our university has been conducting safety and health risk assessments in accordance with the Basic Health and Safety Policy established in 2005. In this context, a risk assessment of chemical substances has been in place. The implementation of chemical substance risk assessment became mandatory by Japanese law in FY 2016. At our university, the series of safety risk assessments has totaled approximately 6,500 cases. Of these, the most common damage predicted was "Fire" at around 16%, followed by "Burn" at about 13%, and "Chemical burn" at approximately 11%. Of the risk assessments in which "Fire" was the predicted damage, "Chemical substance" was the most frequently identified hazard. Specifically, around 40% of "Chemical substance" was "Flammable liquid", about 30% was "Spontaneously combustible substance and water-prohibiting substance", and approximately 9% was "Other hazardous material". It should be noted that there was a negative association between the percentage of risk assessments performed and the percentage of actual accidents that occurred. That is, what is strongly recognized as a hazard in risk assessment tends to have fewer occurrences as an actual accident cause. As a rule, the identified hazard in the risk assessment and the main cause of the actual accident were consistent, and the risk assessment based on the assumption of several predictable types of damage from a single hazard could have been directly attributed to the prevention of actual accidents. [ABSTRACT FROM AUTHOR]

The concept of substance is considered fundamental in order to understand chemistry and other related concepts, but many problems have been reported about its learning process. Considering the importance of textbooks in the training of chemistry teachers, this study aimed to identify the concepts of substance in general chemistry textbook glossaries. In addition, the study assessed the concepts of substance in relation to other chemical concepts and, when available, compared them with the concepts established by the IUPAC (Compendium of chemical terminology, 2 ed. Blackwell Scientific Publications, Oxford, 1997). The methodology employed was content analysis and the results showed that concepts and statements related to the term 'substance' are different in the general chemistry textbooks analyzed. They also differ from those stated by IUPAC. Furthermore, it was found that many concepts are dependent on the concept of substance. It is concluded that there must be a greater effort from the community of chemists and the teaching of chemistry in the search for conceptual uniformity to reduce the problems of conceptual understanding. [ABSTRACT FROM AUTHOR]

From organic synthesis to quantum chemical calculation, chemists interact with chemical substances in a wide variety of ways. But what even is a chemical substance? My aim is to propose a notion of chemical substance that is consistent with the way in which chemical substances are individuated in chemistry, addressing gaps in previous conceptions of chemical substance. Water is employed as a case study to develop the account, not only because it is a familiar example of a chemical substance, but also because its structural peculiarities make it an ideal test case for drawing out potential issues and limitations. Examining four distinct views of chemical substance—the microstructural, thermodynamic, purification, and a functional/relational account—I conclude that each has considerable drawbacks when used as a standalone concept. However, these accounts are not rendered obsolete, but are combined into a semi-pluralist conceptual patchwork. My interactive account of chemical substance is consistent with existing substance descriptions and chemical practice. [ABSTRACT FROM AUTHOR]

Background: Escherichia coli (E. coli) remains one of the leading agents of urinary tract infection (UTIs), it has become resistant to many drugs. Current work aimed to evaluate some chemical substances as antibacterial agents and molecular study of virulence factors associated with UTIs. Methods: This work involved 133 urine specimens obtained from females' patients suffering from UTIs, Methods of well diffusion and disk diffusion were achieved to assay the effect of some chemical substances and antibiogram profiles toward Sulfamethoxazole-trimethoprim (SXT)-resistant E. coli respectively. Virulence genes were done based on the technique of Polymerase Chain Reaction (PCR). Results: The results recorded 49/133 (36.84%) E. coli among women suffering UTIs, 28/49 (57.14%) were resistant to SXT drug. imipenem, meropenem, and nitrofurantoin were recorded more effectively. Chemicals substances at the concentration 0.3 (g/ml) recorded percentages of inhibition, reaching 9.143±1.442, 15.36±0.5914, and 21.82±0.8699 for NaHCO3, Ch4c, and Viroxide Super™ respectively. PCR demonstrated that 28/28 (100%) of SXT-resistant E. coli isolates were harbored Sul-2, FeoB and PapC genes, while 14/28 (50%), 15/28 (53.57%), 19/28 (67.85%) and 26/28 (92.85%) in U250 (pet), FumC, Sul-1 and IutA genes, respectively. Sul-3 gene was not observed. Conclusions: Observed a high percentage of E. coli that were resistant to SXT drug, and having several virulence genes, poses a real threat, it requires a real pause to create substitutions to limit the spreading of this threat. [ABSTRACT FROM AUTHOR]

Background: Chemical veterans are commonly faced with physical, psychological, occupational and social problems. These veterans use relatively high levels of complementary and alternative medicine. Purpose: The current study aimed to investigate the relationship between complementary and alternative medicines (CAM) usage and quality of life of chemical warfare veterans. Material and methods: Three hundred and sixty chemical veterans were assessed using a cross-sectional correlational study design. The study was conducted in infirmaries affiliated to the Kerman Foundation of Martyrs and Veterans Affairs, in southeast Iran, from 20 April to 20 July 2019. A questionnaire developed by researchers on the use of CAM, and SF-36 to assess the quality of life were used for data collection. Results: At least one type of CAM was used by 90% of the samples in the past year. The most common were prayer and herbal medicines. The mean quality of life in chemical veterans was 47.17 ± 18.36. The quality of life score was not significantly different between CAM and non-CAM users (P > 0.05). Conclusion: Chemical veterans have a poor quality of life. Although they use a variety of CAM methods along with other treatments, they do not have a significant effect on their quality of life. [ABSTRACT FROM AUTHOR]

Background: Toxic agents are chemical substances or physical agents that, when interacting with living organisms, cause harmful effects. For animals, toxic products include those intended to combat endo and ectoparasites, rodenticide products, and heavy metals. Minerals and dietary additives, even if essential to the animal, can become toxic agents, among which sodium chloride, copper, urea, and ionophore antibiotics stand out. This study aimed to survey the diagnoses of accidental poisoning in ruminants over 65 years as recorded in the files of the Pathological Anatomy Sector of the Federal Rural University of Rio de Janeiro. Materials, Methods & Results: The diagnoses of poisoning by ticks, rodenticides, heavy metals, macro and micronutrients, and dietary additives in ruminants were made based on the association of epidemiological, clinical, and anatomopathological findings and, in some cases, by histochemical (rubeanic acid and Masson trichrome) and toxicological examinations. A review of data recorded over 65 years identified 372 poisonings in ruminants. Of these, 85.5% (318/372) were in bovine species and 14.5% (54/372) in goats, sheep, and buffaloes. The outbreak of poisoning by organophosphates resulted in the death of 16 cattle that ingested contaminated broken rice and corn. The spraying of this product on the bags was intended to control insects. Intoxication due to excessive administration of abamectin resulted in the intoxication of 16 calves, in two distinct farms. Toxicosis caused by coumarin derivatives resulted in the death of six cattle after accidental ingestion of these rodenticides near the pens. Arsenic poisoning occurred due to ingestion of ant poison, available in bone meal and a mineral salt, through baths with arsenic-based ticks, or in cases later confirmed by toxicological analysis, resulting in the death of 109 cattle. Sodium chloride toxicosis resulted in the death of 10 sheep that became ill in two farms after excessive consumption of salt and private access to water. The diagnosed copper poisoning resulted in the death of 165 ruminants (154 cattle, 10 sheep, and 1 goat). Urea poisoning occurred due to excessive ingestion by 13 cattle and 4 buffaloes, without prior adaptation. Cases of poisoning by ionophore antibiotics occurred in 11 sheep, 18 buffaloes, and 4 cattle. In all cases, the source of exposure was mineral salt and/or feed with an excess of ionophores. The results of the laboratory tests varied according to the type of intoxication. Discussion: Among the means of diagnosing poisoning by toxic agents, minerals, and dietary additives, anamnesis should be detailed and highlighted to present all relevant information. It is the basis for toxicological diagnosis, because it generates information that helps in the definitive elucidation of cases and establishing control and prophylaxis plans, facilitates the prediction of prognosis, and directs the application of appropriate therapy, when possible. In the intoxication diagnoses reported here, the toxicological examination was important in elucidating the toxicosis caused by organophosphates, coumarin derivatives, arsenic, and copper, but the referral for toxicological analysis was previously indicated by a hypothesis generated during the anamnesis. Therefore, anamnesis becomes important yet elusive as toxicological examination leading to diagnosing intoxication. [ABSTRACT FROM AUTHOR]

Chemicals are not a risk for only chemical workers but also for all living beings that come into contact with it. The chemicals cause the pollution of air, food, drinking and using water needed, damage to the natural environment and change of ecosystem, environment and health negatively. The most effective method of eliminating or reducing the negative effects of chemical substances is to know the risks arising from the chemical substances and to analyze and prevent the risks. It is of great importance to classify, label, pack, store, transport, use and dispose of chemical substances and wastes in accordance with the determined rules and regulations in the prevention of risks. In this article, the classification of chemical substances and wastes, labeling, packaging, the characteristics of chemical material storage, the rules of storage and transportation of chemicals. The rules and legislation for the disposal of chemical wastes in the R & D organization was examined. [ABSTRACT FROM AUTHOR]

The scientific consensus model USEtox® has been developed since 2003 under the auspices of the United Nations Environment Programme-Society of Environmental Toxicology and Chemistry Life Cycle Initiative as a harmonized approach for characterizing human and freshwater toxicity in life cycle assessment and other comparative assessment frameworks. Using physicochemical substance properties, USEtox quantifies potential human toxicity and freshwater ecotoxicity impacts by combining environmental fate, exposure, and toxicity effects information, considering multimedia fate and multipathway exposure processes. The main source to obtain substance properties for USEtox 1.01 and 2.0 is the Estimation Program Interface (EPI Suite™) from the US Environmental Protection Agency. However, since the development of the original USEtox substance databases, new chemical regulations have been enforced in Europe, such as the Registration, Evaluation, Authorisation and Restriction of Chemicals (REACH) and the Plant Protection Products regulations. These regulations require that a chemical risk assessment for humans and the environment is performed before a chemical is placed on the European market. Consequently, additional physicochemical property data and new toxicological endpoints are now available for thousands of chemical substances. The aim of the present study was to explore the extent to which the new available data can be used as input for USEtox-especially for application in environmental footprint studies-and to discuss how this would influence the quantification of fate and exposure factors. Initial results show that the choice of data source and the parameters selected can greatly influence fate and exposure factors, leading to potentially different rankings and relative contributions of substances to overall human toxicity and ecotoxicity impacts. Moreover, it is crucial to discuss the relevance of the exposure factor for freshwater ecotoxicity impacts, particularly for persistent highly adsorbing and bioaccumulating substances. Environ Toxicol Chem 2017;36:3463-3470. © 2017 The Authors. Environmental Toxicology and Chemistry Published by Wiley Periodicals, Inc. on behalf of SETAC. [ABSTRACT FROM AUTHOR]

A chemical substance (CS) is instantiated in the material world by a number of quantities of such substance (QCSs), placed in different locations. A change of location implies a change in the net of relationships entertained by the QCS with the region wherein it is found. This fact entails changes of the ontological status of the CS, as this is not fully determined by the inherent features of the CS and includes a relevant relational contribution. In order to demonstrate this thesis, we have chosen to analyse the status of quantities of a same CS that are synchronically located in different spacetime regions: a synthetic lab, a lab where the QCS is turned into a material, an industrial plant, the market where the QCS gets a price and a dump waste where the QCS is discarded, respectively: The use of first-order predicate logic, mereology and locative logic allows carrying out a regimentation process that highlights the ontological commitments implied by the formal expressions through which each element of the aforementioned series can be described. The presence of relational properties discloses the systemic nature of the CS instantiated within a spacetime region. The implications of such an aspect are discussed. [ABSTRACT FROM AUTHOR]

Objectives To protect public health from risk, the Minister of Environment in Korea legislated an act concerning the registration and evaluation of chemical substances. In this study, we estimated the value of a statistical life (VSL) of carcinogenic chemicals to evaluate the socioeconomic analysis in Korea. Methods The estimation of the health benefit can be calculated through an individual's VSL and willingness to pay (WTP). To estimate the VSL and WTP, we used a contingent valuation method through a web-based survey. Results The survey is conducted with 1434 people living in Seoul and six large cities. An analysis of the survey is essential to review the distribution of the characteristics of the target population. The statistically significant variables affecting the WTP are location, age, household income, quality of life. Through the review of data, we secured statistical validity. The WTP was estimated as 41205 Korean won (KRW)/person, and the estimated VSL appeared as 796 million KRW/person. Conclusions There is a case in which the amount of statistical life value is estimated in connection with domestic environmental policy, fine dust, etc. However, there are no cases of evaluation for chemical. The utilization of this result is possible for conducting other study with chemicals. [ABSTRACT FROM AUTHOR]

Abstract: The differential transcriptional responses of a freesia 1-aminocyclopropane-l-carboxylate synthase gene (FhACS1) to exogenous ethephon, abscisic acid (ABA), salicylic acid (SA), indole-3-acetic acid (IAA), 6-benzylaminopurine (6-BA), silver thiosulfate (STS) and sugar were studied using real-time quantitative PCR. Pretreatments for periods of 24h were evaluated in bud 3 and bud 6 on the inflorescence during freesia flower development and senescence. The results showed that individual exogenous pretreatment with ethephon, IAA, ABA and SA all resulted in the accelerated senescence of freesia flowers compared to those of control buds. Ethephon enhanced FhACS1 expression and extended this high expression; IAA induced an earlier and higher accumulation of FhACS1 transcripts in bud 3, held-up FhACS1 transcript accumulation in later development in bud 6; ABA evidently stimulated a stronger and earlier response of FhACS1 and SA led a higher and longer FhACS1 transcript accumulation. Conversely, 6-BA, STS and sugar pretreatments had a positive effect on the flower development and downregulated FhACS1 expression. Among these treatments, 6-BA significantly restrained the accumulation of the FhACS1 transcript, especially in bud 6; STS also lowered the FhACS1 transcription level overall; while sugar postponed the arrival of the FhACS1 expression peak and significantly decreased the amount of FhACS1 transcript. These results show that these phytohormones and chemical substances signals lead to transcriptional regulation of FhACS1, conjecturing that FhACS1 may participate in the complex hormonal and developmental net works in freesia flower senescence. [Copyright &y& Elsevier]

The bulk of Duhem’s writing which bears on the understanding of mixtures suggests he adopted an Aristotelian position which he opposed only to the atomic view. A third view from antiquity—that of the Stoics—seems not to be taken into account. But his lines of thought are not always as explicit as could be wished. The Stoic view is considered here from a perspective which Duhem might well have adopted. This provides a background against which his somewhat unorthodox Aristotelianism might be understood. [Copyright &y& Elsevier]