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Fulltext Quisy-SDS accelerates the searching process of chemical safety datasheet

Muhammad Firdaus Othman,, Nor Aimi Abdul Wahab, Suhaiza Hasan, Marina Mokhtar, Noorezal Atfyinna Mohd Napiah, Mohd Noor Mokhtar, et al.

Jurnal Inovasi Malaysia, 2019;2(2):123-139.
MyJurnal

Teaching, learning and reseach activities in chemical laboratory usually involves a variety of hazardous chemicals. All chemicals stored in the laboratories should be accompanied by a safety data sheet which contains information such as chemical composition, safety precautions for handling and storing chemicals and emergency measures in case of accident. Ineffective management of chemical safety data sheet makes it difficult to access and resulting in slow action taken in the event of accident. To overcome this problem, Quisy-SDS was introduced to ensure a more effective chemical safety information management. Quisy-SDS provides a convenient method for all lab users and emergency respondents to acess the chemical safety information. This method uses a Quick Response (QR) code and website that allow users to acess the information in no time, anytime and anywhere. The use of Quisy-SDS has successfully reduced the search time of chemical safety information by 98% compared to the previous method.

Matched MeSH terms: Hazardous Substances
Fulltext Analysis of boiling liquid expanding vapour explosion (BLEVE) due to loss of containment for liquefied petroleum gas (LPG) road tankers

Mohammed Taher Alfates, Biak, Dayang Radiah Awang

Journal of Occupational Safety and Health, 2019;16(2):11-19.
MyJurnal

Transport of fuel is essential to ensure supplies are delivered as per requested by the industrial sites or other demands. Numerous accidents have been reported and recorded in which loss of containment of hazardous chemicals occurred and led to disastrous outcomes. This paper presents the analysis of Boiling Liquid Expanding Vapour Explosion (BLEVE) due to loss of containment for Liquefied Petroleum Gas (LPG) road tankers. The main objective of this paper is to evaluate the potential consequences resulting from overpressure blast and thermal radiation of tankers carrying LPG to the people and the surrounding. The aim is also to compare the outcomes obtained from PHAST software simulator 8.11 with that of established mathematical model. Malaysia North-south Expressway (NSE) was selected as the location of the incident. The volume, weather parameters and properties of LPG were identified. It was found that the effect of BLEVE on people and structures was catastrophic. The results obtained from the mathematical model were similar with that modelled using PHAST software simulator.

Matched MeSH terms: Hazardous Substances
Fulltext Empowering occupational health doctors through the occupational safety & health (noise exposure) regulations 2019

Manivasagam, Dayanath

Journal of Occupational Safety and Health, 2019;16(1):1-7.
MyJurnal

The Department of Occupational Safety and Health Malaysia (DOSH) is the authority responsible to safeguard the occupational safety, health and welfare of workers in Malaysia. Occupational noise-related hearing disorders are the leading type of occupational diseases recorded by DOSH every year. Occupational Health Doctor (OHD) is a competency recognized by DOSH and their scope of duties in industries is currently confined to conduct medical surveillance for workers with hazardous chemical exposure and confined space medical fitness examination. The duties of OHD are good to be expanded by empowering more of their roles in industrial activities involving other legislations under DOSH. The noise exposure regulation under the Factories and Machinery Act (FMA) 1967 has been governing the worker’s exposure to hazardous industrial noise and preventing noise-induced hearing loss (NIHL) since 1989. However, the provisions of the regulation need to be strengthened in some essential medical elements of the Hearing Conservation Programme (HCP) for a comprehensive prevention of NIHL at the workplace. Recently enacted Occupational Safety and Health (Noise Exposure) Regulations 2019 offer a wider coverage of workers in ten sectors of industries applicable under the Occupational Safety and Health Act (OSHA) 1994. The current regulatory requirements for management of workplace noise have many improvements compared to the existing law. Enhancement in the medical requirements of industrial audiometry is made prominent by involving OHDs to interpret audiograms and conduct medical examination for workers. The reporting of occupational noise-related hearing disorders to DOSH is outlined better in the new regulation. The occurrence of NIHL and other related hearing disorders are expected to reduce eventually after the introduction of Occupational Safety and Health (Noise Exposure) Regulations 2019. The OHDs will play a pivotal role in industrial audiometry and prevention of hearing disorders among the working population.

Matched MeSH terms: Hazardous Substances
Fulltext Protection of Reinforced Concrete Structures of Waste Water Treatment Reservoirs with Stainless Steel Coating Using Arc Thermal Spraying Technique in Acidified Water

Lee HS, Park JH, Singh JK, Ismail MA

Materials (Basel), 2016 Sep 03;9(9).
PMID: 28773875 DOI: 10.3390/ma9090753

Waste water treatment reservoirs are contaminated with many hazardous chemicals and acids. Reservoirs typically comprise concrete and reinforcement steel bars, and the main elements responsible for their deterioration are hazardous chemicals, acids, and ozone. Currently, a variety of techniques are being used to protect reservoirs from exposure to these elements. The most widely used techniques are stainless steel plating and polymeric coating. In this study, a technique known as arc thermal spraying was used. It is a more convenient and economical method for protecting both concrete and reinforcement steel bar from deterioration in waste water treatment reservoirs. In this study, 316L stainless steel coating was applied to a concrete surface, and different electrochemical experiments were performed to evaluate the performance of coatings in different acidic pH solutions. The coating generated from the arc thermal spraying process significantly protected the concrete surface from corrosion in acidic pH solutions, owing to the formation of a double layer capacitance-a mixture of Cr3+ enriched with Cr₂O₃ and Cr-hydroxide in inner and Fe3+ oxide on the outer layer of the coating. The formation of this passive film is defective owing to the non-homogeneous 316L stainless steel coating surface. In the pH 5 solution, the growth of a passive film is adequate due to the presence of un-dissociated water molecules in the aqueous sulfuric acid solution. The coated surface is sealed with alkyl epoxide, which acts as a barrier against the penetration of acidic solutions. This coating exhibits higher impedance values among the three studied acidic pH solutions.

Matched MeSH terms: Hazardous Substances
Fulltext Causes of genome instability: the effect of low dose chemical exposures in modern society

Langie SA, Koppen G, Desaulniers D, Al-Mulla F, Al-Temaimi R, Amedei A, et al.

Carcinogenesis, 2015 Jun;36 Suppl 1:S61-88.
PMID: 26106144 DOI: 10.1093/carcin/bgv031

Genome instability is a prerequisite for the development of cancer. It occurs when genome maintenance systems fail to safeguard the genome's integrity, whether as a consequence of inherited defects or induced via exposure to environmental agents (chemicals, biological agents and radiation). Thus, genome instability can be defined as an enhanced tendency for the genome to acquire mutations; ranging from changes to the nucleotide sequence to chromosomal gain, rearrangements or loss. This review raises the hypothesis that in addition to known human carcinogens, exposure to low dose of other chemicals present in our modern society could contribute to carcinogenesis by indirectly affecting genome stability. The selected chemicals with their mechanisms of action proposed to indirectly contribute to genome instability are: heavy metals (DNA repair, epigenetic modification, DNA damage signaling, telomere length), acrylamide (DNA repair, chromosome segregation), bisphenol A (epigenetic modification, DNA damage signaling, mitochondrial function, chromosome segregation), benomyl (chromosome segregation), quinones (epigenetic modification) and nano-sized particles (epigenetic pathways, mitochondrial function, chromosome segregation, telomere length). The purpose of this review is to describe the crucial aspects of genome instability, to outline the ways in which environmental chemicals can affect this cancer hallmark and to identify candidate chemicals for further study. The overall aim is to make scientists aware of the increasing need to unravel the underlying mechanisms via which chemicals at low doses can induce genome instability and thus promote carcinogenesis.

Matched MeSH terms: Hazardous Substances/adverse effects*
Fulltext Chemical compounds from anthropogenic environment and immune evasion mechanisms: potential interactions

Kravchenko J, Corsini E, Williams MA, Decker W, Manjili MH, Otsuki T, et al.

Carcinogenesis, 2015 Jun;36 Suppl 1:S111-27.
PMID: 26002081 DOI: 10.1093/carcin/bgv033

An increasing number of studies suggest an important role of host immunity as a barrier to tumor formation and progression. Complex mechanisms and multiple pathways are involved in evading innate and adaptive immune responses, with a broad spectrum of chemicals displaying the potential to adversely influence immunosurveillance. The evaluation of the cumulative effects of low-dose exposures from the occupational and natural environment, especially if multiple chemicals target the same gene(s) or pathway(s), is a challenge. We reviewed common environmental chemicals and discussed their potential effects on immunosurveillance. Our overarching objective was to review related signaling pathways influencing immune surveillance such as the pathways involving PI3K/Akt, chemokines, TGF-β, FAK, IGF-1, HIF-1α, IL-6, IL-1α, CTLA-4 and PD-1/PDL-1 could individually or collectively impact immunosurveillance. A number of chemicals that are common in the anthropogenic environment such as fungicides (maneb, fluoxastrobin and pyroclostrobin), herbicides (atrazine), insecticides (pyridaben and azamethiphos), the components of personal care products (triclosan and bisphenol A) and diethylhexylphthalate with pathways critical to tumor immunosurveillance. At this time, these chemicals are not recognized as human carcinogens; however, it is known that they these chemicalscan simultaneously persist in the environment and appear to have some potential interfere with the host immune response, therefore potentially contributing to promotion interacting with of immune evasion mechanisms, and promoting subsequent tumor growth and progression.

Matched MeSH terms: Hazardous Substances/adverse effects*; Hazardous Substances/immunology*
Improving safety-related knowledge, attitude and practices of nurses handling cytotoxic anticancer drug: pharmacists' experience in a general hospital, Malaysia

Keat CH, Sooaid NS, Yun CY, Sriraman M

Asian Pac J Cancer Prev, 2013;14(1):69-73.
PMID: 23534806

BACKGROUND: An increasing trend of cytotoxic drug use, mainly in cancer treatment, has increased the occupational exposure among the nurses. This study aimed to assess the change of nurses' safety-related knowledge as well as attitude levels and subsequently to assess the change of cytotoxic drug handling practices in wards after a series of pharmacist-based interventions.
MATERIALS AND METHODS: This prospective interventional study with a before and after design requested a single group of 96 nurses in 15 wards actively providing chemotherapy to answer a self-administered questionnaire. A performance checklist was then used to determine the compliance of all these wards with the recommended safety measures. The first and second assessments took 2 months respectively with a 9-month intervention period. Pharmacist-based interventions included a series of technical, educational and administrative support measures consisting of the initiation of closed-system cytotoxic drug reconstitution (CDR) services, courses, training workshops and guideline updates.
RESULTS: The mean age of nurses was 32.2∓6.19 years. Most of them were female (93.8%) and married (72.9%). The mean knowledge score of nurses was significantly increased from 45.5∓10.52 to 73.4∓8.88 out of 100 (p<0.001) at the end of the second assessment. Overall, the mean practice score among the wards was improved from 7.6∓5.51 to 15.3∓2.55 out of 20 (p<0.001).
CONCLUSIONS: The pharmacist-based interventions improved the knowledge, attitude and safe practices of nurses in cytotoxic drug handling. Further assessment may help to confirm the sustainability of the improved practices.

Matched MeSH terms: Hazardous Substances/toxicity*
Bioluminescent method for the rapid screening of toxic heayy metals in environmental samples using Photobacterium leiognathi strain AK-MIE

Kassim A, Halmi MIE, Gani SSA, Zaidan UH, Othman R, Mahmud K, et al.

Ecotoxicol Environ Saf, 2020 Jun 15;196:110527.
PMID: 32278138 DOI: 10.1016/j.ecoenv.2020.110527

Assessment of eco-toxicant using bioluminescent bacterial assay is a widely used and globally accepted method. In this work, a new luminescent bacterium was isolated from squid (Loligo duvauceli) and identified as Photobacterium leiognathi strain AK-MIE using 16S rRNA, phylogeny analysis. The predicted optimum conditions by RSM were 2.76% (w/v) NaCl, 2.28% (w/v) peptone, 0.34% (w/v) yeast extract, and pH 6.83 with 541,211.80 RLU of luminescent production whereas the predicted optimum conditions by ANN were 2.21% (w/v) NaCl, 2.27% (w/v) peptone, 0.39% (w/v) yeast extract, and pH 6.94 which produced 541,986.20 RLU. The validation analysis of both RSM and ANN show 0.60% and 0.69% deviation from the predicted results indicating that both models provided good quality predictions with ANN showing a superior data fitting capability for non-linear regression analysis. Toxicity tests show strain AK-MIE was sensitive to mercury (concentration causing 50% inhibition or IC50 of 0.00978 mgL-1), followed by cadmium (IC50 of 0.5288 mgL-1), copper IC50 of (0.8117 mgL-1), silver (IC50 of 1.109 mgL-1), and lead (IC50 of 10.71 mgL-1) which are more sensitive than previously isolated luminescent bacteria, suggesting that strain AK-MIE has the potential to be used in toxicity assessment of heavy metals in the environment. Based on the field trial results, several sediment samples from industrial areas in Bangi, Selangor managed to inhibit the bioluminescence of strain AK-MIE. Validation method carried out using ICP-MS proved the presence of several toxic heavy metal elements.

Matched MeSH terms: Hazardous Substances/analysis*; Hazardous Substances/toxicity
Toxicants in folk remedies: implications of elevated blood lead in an American-born infant due to imported diaper powder

Karwowski MP, Morman SA, Plumlee GS, Law T, Kellogg M, Woolf AD

Environ Geochem Health, 2017 Oct;39(5):1133-1143.
PMID: 27704308 DOI: 10.1007/s10653-016-9881-6

Though most childhood lead exposure in the USA results from ingestion of lead-based paint dust, non-paint sources are increasingly implicated. We present interdisciplinary findings from and policy implications of a case of elevated blood lead (13-18 mcg/dL, reference level <5 mcg/dL) in a 9-month-old infant, linked to a non-commercial Malaysian folk diaper powder. Analyses showed the powder contains 62 % lead by weight (primarily lead oxide) and elevated antimony [1000 parts per million (ppm)], arsenic (55 ppm), bismuth (110 ppm), and thallium (31 ppm). These metals are highly bioaccessible in simulated gastric fluids, but only slightly bioaccessible in simulated lung fluids and simulated urine, suggesting that the primary lead exposure routes were ingestion via hand-mouth transmission and ingestion of inhaled dusts cleared from the respiratory tract. Four weeks after discontinuing use of the powder, the infant's venous blood lead level was 8 mcg/dL. Unregulated, imported folk remedies can be a source of toxicant exposure. Additional research on import policy, product regulation, public health surveillance, and culturally sensitive risk communication is needed to develop efficacious risk reduction strategies in the USA. The more widespread use of contaminated folk remedies in the countries from which they originate is a substantial concern.

Matched MeSH terms: Hazardous Substances/analysis; Hazardous Substances/blood
Visible-Light Driven Effective Photocatalytic Degradation of Methylene Blue Dye Using Perforated Curly Zn0.1Ni0.9O Nanosheets

Karthikeyan V, Gnanamoorthy G, Varun Prasath P, Narayanan V, Sagadevan S, Umar A, et al.

J Nanosci Nanotechnol, 2020 Sep 01;20(9):5759-5764.
PMID: 32331175 DOI: 10.1166/jnn.2020.17898

Herein, we report the facile synthesis, characterization and visible-light-driven photocatalytic degradation of perforated curly Zn0.1Ni0.9O nanosheets synthesized by hydrothermal process. The X-ray diffraction (XRD) and scanning electron microscopy (SEM) studies confirmed the cubic phase crystalline structure and growth of high density perforated curly Zn0.1Ni0.9O nanosheets, respectively. As a photocatalyst, using methylene blue (MB) as model pollutant, the synthesized nanosheets demonstrated a high degradation efficiency of ~76% in 60 min under visible light irradiation. The observed results suggest that the synthesized Zn0.1Ni0.9O nanosheets are attractive photocatalysts for the degradation of toxic organic waste in the water under visible light.

Matched MeSH terms: Hazardous Substances
A novel nanobiosensor for the detection of paraoxon using chitosan-embedded organophosphorus hydrolase immobilized on Au nanoparticles

Karami R, Mohsenifar A, Mesbah Namini SM, Kamelipour N, Rahmani-Cherati T, Roodbar Shojaei T, et al.

Prep Biochem Biotechnol, 2015 Oct 26.
PMID: 26503886

Organophosphorus (OP) compounds are one of the most hazardous chemicals used as insecticides/pesticide in agricultural practices. A large variety of OP compounds are hydrolyzed by organophosphorus hydrolases (OPH; EC 3.1.8.1). Therefore, OPHs are among the most suitable candidates which could be used in designing enzyme-based sensors for detecting OP compounds. In the present work, a novel nanobiosensor for the detection of paraoxon was designed and fabricated. More specifically, OPH was covalently embedded onto chitosan and the enzyme-chitosan bioconjugate was then immobilized on negatively charged gold nanoparticles (AuNPs) electrostatically. The enzyme was immobilized on AuNPs without chitosan as well to compare the two systems in terms of detection limit and enzyme stability under different pH and temperature conditions. Coumarin 1, a competitive inhibitor of the enzyme, was used as a fluorogenic probe. The emission of coumarin 1 was effectively quenched by the immobilized Au-NPs when bound to the developed nanobioconjugates. However, in the presence of paraoxon, coumarin 1 left the nanobioconjugate leading to enhanced fluorescence intensity. Moreover, compared to the immobilized enzyme without chitosan, the chitosan-immobilized enzyme was found to possess decreased Km value by over 50%, increased Vmax and Kcat values by around 15% and 74%, respectively. Higher stability within a wider range of pH (2-12) and temperature (25-90°C) was also achieved. The method worked in the 0 to 1050 nM concentration ranges, and had a detection limit as low as 5 × 10(-11) M.

Matched MeSH terms: Hazardous Substances
Prioritization of reproductive toxicants in unconventional oil and gas operations using a multi-country regulatory data-driven hazard assessment

Inayat-Hussain SH, Fukumura M, Muiz Aziz A, Jin CM, Jin LW, Garcia-Milian R, et al.

Environ Int, 2018 08;117:348-358.
PMID: 29793188 DOI: 10.1016/j.envint.2018.05.010

BACKGROUND: Recent trends have witnessed the global growth of unconventional oil and gas (UOG) production. Epidemiologic studies have suggested associations between proximity to UOG operations with increased adverse birth outcomes and cancer, though specific potential etiologic agents have not yet been identified. To perform effective risk assessment of chemicals used in UOG production, the first step of hazard identification followed by prioritization specifically for reproductive toxicity, carcinogenicity and mutagenicity is crucial in an evidence-based risk assessment approach. To date, there is no single hazard classification list based on the United Nations Globally Harmonized System (GHS), with countries applying the GHS standards to generate their own chemical hazard classification lists. A current challenge for chemical prioritization, particularly for a multi-national industry, is inconsistent hazard classification which may result in misjudgment of the potential public health risks. We present a novel approach for hazard identification followed by prioritization of reproductive toxicants found in UOG operations using publicly available regulatory databases.
METHODS: GHS classification for reproductive toxicity of 157 UOG-related chemicals identified as potential reproductive or developmental toxicants in a previous publication was assessed using eleven governmental regulatory agency databases. If there was discordance in classifications across agencies, the most stringent classification was assigned. Chemicals in the category of known or presumed human reproductive toxicants were further evaluated for carcinogenicity and germ cell mutagenicity based on government classifications. A scoring system was utilized to assign numerical values for reproductive health, cancer and germ cell mutation hazard endpoints. Using a Cytoscape analysis, both qualitative and quantitative results were presented visually to readily identify high priority UOG chemicals with evidence of multiple adverse effects.
RESULTS: We observed substantial inconsistencies in classification among the 11 databases. By adopting the most stringent classification within and across countries, 43 chemicals were classified as known or presumed human reproductive toxicants (GHS Category 1), while 31 chemicals were classified as suspected human reproductive toxicants (GHS Category 2). The 43 reproductive toxicants were further subjected to analysis for carcinogenic and mutagenic properties. Calculated hazard scores and Cytoscape visualization yielded several high priority chemicals including potassium dichromate, cadmium, benzene and ethylene oxide.
CONCLUSIONS: Our findings reveal diverging GHS classification outcomes for UOG chemicals across regulatory agencies. Adoption of the most stringent classification with application of hazard scores provides a useful approach to prioritize reproductive toxicants in UOG and other industries for exposure assessments and selection of safer alternatives.

Matched MeSH terms: Hazardous Substances/analysis*
Nanoscale patterning by AFM lithography and its application on the fabrication of silicon nanowire devices

Hutagalung SD, Kam CL, Darsono T

Sains Malaysiana, 2014;43:267-272.

Many techniques have been applied to fabricate nanostructures via top-down approach such as electron beam lithography. However, most of the techniques are very complicated and involves many process steps, high cost operation as well as the use of hazardous chemicals. Meanwhile, atomic force microscopy (AFM) lithography is a simple technique which is considered maskless and involves only an average cost and less complexity. In AFM lithography, the movement of a probe tip can be controlled to create nanoscale patterns on sample surface. For silicon nanowire (SiNW) fabrication, a conductive tip was operated in non-contact AFM mode to grow nanoscale oxide patterns on silicon-on-insulator (SOI) wafer surface based on local anodic oxidation (LAO) mechanism. The patterned structure was etched through two steps of wet etching processes. First, the TMAH was used as the etchant solution for Si removing. In the second step, diluted HF was used to remove oxide mask in order to produce a completed SiNW based devices. A SiNW based device which is formed by a nanowire channel, source and drain pads with lateral gate structures can be fabricated by well controlling the lithography process (applied tip voltage and writing speed) as well as the etching processes.

Matched MeSH terms: Hazardous Substances
Fulltext Assessing the carcinogenic potential of low-dose exposures to chemical mixtures in the environment: focus on the cancer hallmark of tumor angiogenesis

Hu Z, Brooks SA, Dormoy V, Hsu CW, Hsu HY, Lin LT, et al.

Carcinogenesis, 2015 Jun;36 Suppl 1:S184-202.
PMID: 26106137 DOI: 10.1093/carcin/bgv036

One of the important 'hallmarks' of cancer is angiogenesis, which is the process of formation of new blood vessels that are necessary for tumor expansion, invasion and metastasis. Under normal physiological conditions, angiogenesis is well balanced and controlled by endogenous proangiogenic factors and antiangiogenic factors. However, factors produced by cancer cells, cancer stem cells and other cell types in the tumor stroma can disrupt the balance so that the tumor microenvironment favors tumor angiogenesis. These factors include vascular endothelial growth factor, endothelial tissue factor and other membrane bound receptors that mediate multiple intracellular signaling pathways that contribute to tumor angiogenesis. Though environmental exposures to certain chemicals have been found to initiate and promote tumor development, the role of these exposures (particularly to low doses of multiple substances), is largely unknown in relation to tumor angiogenesis. This review summarizes the evidence of the role of environmental chemical bioactivity and exposure in tumor angiogenesis and carcinogenesis. We identify a number of ubiquitous (prototypical) chemicals with disruptive potential that may warrant further investigation given their selectivity for high-throughput screening assay targets associated with proangiogenic pathways. We also consider the cross-hallmark relationships of a number of important angiogenic pathway targets with other cancer hallmarks and we make recommendations for future research. Understanding of the role of low-dose exposure of chemicals with disruptive potential could help us refine our approach to cancer risk assessment, and may ultimately aid in preventing cancer by reducing or eliminating exposures to synergistic mixtures of chemicals with carcinogenic potential.

Matched MeSH terms: Hazardous Substances/adverse effects*
Fulltext Storm runoff pollution from a residential catchment in Miri, Sarawak

Ho, C. L. I., Choo, B. Q.

Pertanika Journal of Science & Technology, 2014;22(2):603-611.
MyJurnal

In this paper, stormwater runoff from a residential catchment located in Miri, Sarawak, was characterized to determine the pollutant concentrations and loading. The observed average event mean concentrations were 116 mg/L for TSS, 115 mg/L for COD, 1.5 mg/L for NH3-N, and 0.23 mg/L for Pb. Based on Interim National Water Quality Standards (INWQS) for Malaysia, the average event mean concentration, EMC value for TSS exceeded class II (50 mg/L), exceeded class V (>100 mg/L) for COD, and exceeded class III (0.9 mg/L) for NH3-N. All four water quality parameters exhibited first flush characteristic but to varying magnitude which was influenced by the storm characteristics.

Matched MeSH terms: Hazardous Substances
Are deep eutectic solvents benign or toxic?

Hayyan M, Hashim MA, Hayyan A, Al-Saadi MA, AlNashef IM, Mirghani ME, et al.

Chemosphere, 2013 Feb;90(7):2193-5.
PMID: 23200570 DOI: 10.1016/j.chemosphere.2012.11.004

In continuation of investigation for environmentally benign protocol for new solvents termed deep eutectic solvents (DESs), it is herein reported results concerning the toxicity and cytotoxicity of choline chloride (ChCl) based DESs with four hydrogen bond donors including glycerine, ethylene glycol, triethylene glycol and urea. The toxicity was investigated using two Gram positive bacteria Bacillus subtilis and Staphylococcus aureus, and two Gram negative bacteria Escherichia coli and Pseudomonas aeruginosa. The cytotoxicity effect was tested using the Artemia salina leach. It was found that there was no toxic effect for the tested DESs on all of the studied bacteria confirming their benign effects on these bacteria. Nevertheless, it was found that the cytotoxicity of DESs was much higher than their individual components (e.g. glycerine, ChCl) indicating that their toxicological behavior is different. For our best knowledge this is the first time that toxicity and cytotoxicity of DESs were studied. The toxicity and cytotoxicity of DESs varied depending on the structure of components. Careful usage of the terms non-toxicity and biodegradability must be considered. More investigation on this matter is required.

Matched MeSH terms: Hazardous Substances/toxicity*
Fulltext Niigata Minamata disease: a revisit

Hasni MJ

Malaysian Journal of Public Health Medicine, 2014;14(1):47-54.
MyJurnal

Minamata disease is a well-known mercury contamination that happened in Japan in 1953. Due to demand during world war, second mercury disaster occurred in Niigata Prefecture in 1965. This is a review on the Niigata Minamata disease based on available documents and local expert opinions on the disaster. The aims of this paper are to record exposure history like the source of mercury in Agano River and specific fish that was associated with the disease. It is for an appraisal of the basic mercury exposure control, particularly to protect Japanese and world population during that time. There was indication that initial exposure limit for mercury was calculated incorrectly, and higher safe dose was applied. This epidemiological study is very useful and significant in comprehend the correct estimation of the human exposure to any hazardous substances.

Matched MeSH terms: Hazardous Substances
Fulltext Rapid ecotoxicological tests using bioassay systems - a review

Halmi, M.I.E.

Journal of Biochemistry, Microbiology and Biotechnology, 2016;4(1):29-37.
MyJurnal

The rise in pollution cases globally is expected to increase in line with industrialization.
Monitoring activities for pollutants have been hampered by the astronomical costs of
instrumental-based approach. This has resulted in the intense research on low cost
biomonitoring systems using enzymes, organisms including microorganisms. Only positive
samples are sent for instrumental analysis; dramatically cutting the cost of instrumental
analysis. This review attempts to outline and give due recognition to several selected bioassay
systems that have been tested for their applicability using polluted water samples as a routine
first line-of-defense. This includes small aquatic organisms-based assays, enzymes especially
proteases and bacterial-based systems using respiratory dye or luminescence systems as a
method for toxicant detection.

Matched MeSH terms: Hazardous Substances
Fulltext Assessing the carcinogenic potential of low-dose exposures to chemical mixtures in the environment: the challenge ahead

Goodson WH, Lowe L, Carpenter DO, Gilbertson M, Manaf Ali A, Lopez de Cerain Salsamendi A, et al.

Carcinogenesis, 2015 Jun;36 Suppl 1:S254-96.
PMID: 26106142 DOI: 10.1093/carcin/bgv039

Lifestyle factors are responsible for a considerable portion of cancer incidence worldwide, but credible estimates from the World Health Organization and the International Agency for Research on Cancer (IARC) suggest that the fraction of cancers attributable to toxic environmental exposures is between 7% and 19%. To explore the hypothesis that low-dose exposures to mixtures of chemicals in the environment may be combining to contribute to environmental carcinogenesis, we reviewed 11 hallmark phenotypes of cancer, multiple priority target sites for disruption in each area and prototypical chemical disruptors for all targets, this included dose-response characterizations, evidence of low-dose effects and cross-hallmark effects for all targets and chemicals. In total, 85 examples of chemicals were reviewed for actions on key pathways/mechanisms related to carcinogenesis. Only 15% (13/85) were found to have evidence of a dose-response threshold, whereas 59% (50/85) exerted low-dose effects. No dose-response information was found for the remaining 26% (22/85). Our analysis suggests that the cumulative effects of individual (non-carcinogenic) chemicals acting on different pathways, and a variety of related systems, organs, tissues and cells could plausibly conspire to produce carcinogenic synergies. Additional basic research on carcinogenesis and research focused on low-dose effects of chemical mixtures needs to be rigorously pursued before the merits of this hypothesis can be further advanced. However, the structure of the World Health Organization International Programme on Chemical Safety 'Mode of Action' framework should be revisited as it has inherent weaknesses that are not fully aligned with our current understanding of cancer biology.

Matched MeSH terms: Hazardous Substances/adverse effects*
Fulltext New protocols for the synthesis of 5-amino-7-(4-phenyl)-4,7-dihydro-[1,2,4]triazolo[1,5-a]pyrimidine-6-carboxylate esters using an efficient additive

Ghaffari Khaligh N, Mihankhah T, Titinchi S, Shahnavaz Z, Rafie Johan M

Turk J Chem, 2020;44(4):1100-1109.
PMID: 33488215 DOI: 10.3906/kim-2005-6

This work introduces a new additive named 4,4'-trimethylenedipiperidine for the practical and ecofriendly preparation of ethyl 5-amino-7-(4-phenyl)-4,7-dihydro-[1,2,4]triazolo[1,5-a]pyrimidine-6-carboxylate derivatives. This chemical is commercially available and easy to handle. It also possesses a low melting point and a broad liquid range temperature, high thermal stability, and good solubility in water. Based on green chemistry principles, the reaction was performed in a) a mixture of green solvents i.e. water and ethanol (1:1 v/v) at reflux temperature, and b) the additive was liquefied at 65 °C and the reaction was conducted in the liquid state of the additive. High yields of the desired triazolo-pyrimidines were obtained under both aforementioned conditions. Our results demonstrated that this additive, containing 2 Lewis base sites and able to act as an acceptor-donor hydrogen bonding group, is a novel and efficient alternative to piperidine, owing to its unique properties such as its reduced toxicity, nonflammable nature, nonvolatile state, broad liquid range temperature, high thermal stability, and ability to be safely handled. Furthermore, this additive could be completely recovered and exhibited high recyclability without any change in its chemical structure and no significant reduction in its activity. The current methodology has several advantages: (a) it avoids the use of hazardous materials, as well as toxic, volatile, and flammable solvents, (b) it does not entail tedious processes, harsh conditions, and the multistep preparation of catalysts, (c) it uses a metal-free and noncorrosive catalyst, and (d) reduces the generation of hazardous waste and simple work-up processes. The most important result of this study is that 4,4'-trimethylenedipiperidine can be a promising alternative for toxic, volatile, and flammable base reagents in organic synthesis owing to its unique properties.

Matched MeSH terms: Hazardous Substances

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