Socio-demographic effects on role assignment and associated occupational health and safety issues in artisanal and small-scale gold mining in Amansie Central District, Ghana.

The study employed the binary logistic regression model, Chi-square, and likelihood ratio test to explore the nexus between socio-demographic characteristics and role assignment as well as Occupational Health and Safety (OHS) issues in artisanal and small-scale gold mining (ASGM) undertakings in the Amansie Central District of Ghana. Simple random sampling was employed to sample 250 respondents from three (3) different mining sites. The results revealed that socio-demographic variables such as age, gender, and work experience significantly impacted the type of role assumed by individuals in ASGM undertakings. For the socio-demographic effects on OHS issues, male respondents especially those in the age group between 18 and 35 with less work experience and education had a higher risk of recording injuries/accidents. Other risk factors such as types of role, reasons for ASGM, awareness of OHS hazards, awareness of Personal Protective Equipment (PPE), usage of PPE, arrest for not using PPE, cost of PPE, and frequency of buying PPE had a statistically significant influence on the occurrence of injuries/accidents. It is recommended that the Government implement initiatives to ensure that workers in ASGM operations in Ghana are provided with training, education, resources, and support services to ensure their safety and well-being, taking into account their socio-demographic characteristics. Also, the government and related stakeholders create more jobs through sustainable mining with long-term potential in local districts to address goals 1 (No poverty) and 2 (zero hunger) of the sustainable development goals.

An update on the current status and prospects of nitrosation pathways and possible root causes of nitrosamine formation in various pharmaceuticals.

Over the last two years, global regulatory authorities have raised safety concerns on nitrosamine contamination in several drug classes, including angiotensin II receptor antagonists, histamine-2 receptor antagonists, antimicrobial agents, and antidiabetic drugs. To avoid carcinogenic and mutagenic effects in patients relying on these medications, authorities have established specific guidelines in risk assessment scenarios and proposed control limits for nitrosamine impurities in pharmaceuticals. In this review, nitrosation pathways and possible root causes of nitrosamine formation in pharmaceuticals are discussed. The control limits of nitrosamine impurities in pharmaceuticals proposed by national regulatory authorities are presented. Additionally, a practical and science-based strategy for implementing the well-established control limits is notably reviewed in terms of an alternative approach for drug product N-nitrosamines without published AI information from animal carcinogenicity testing. Finally, a novel risk evaluation strategy for predicting and investigating the possible nitrosation of amine precursors and amine pharmaceuticals as powerful prevention of nitrosamine contamination is addressed.

Bioaccumulation of organochlorine pesticides in the parasite Cosmocerca sp. (Nematoda: Cosmocercidae) and the amphibian host Amietophrynus regularis (Reuss, 1833) within Lagos metropolis, Nigeria.

BACKGROUND: Amphibian species are being threatened worldwide and chemical pollution is one of the leading causes of this decline. The use of agrochemicals such as organochlorine pesticides (OCPs) among the several health and ecological challenges it causes, the sharp amphibian population decline is most pressing.Toad specimens Amietophrynus regularis were sampled from three (3) selected areas; each comprising of natural habitat and dumpsites within Lagos metropolis. METHODS: The congeners of organochlorine pesticides were tested in the liver, intestine, and parasite (Cosmocerca sp.) of the toads and soil samples from the respective locations using gas chromatography-mass spectrometer (GC-MS). Histopathological analyses were conducted on the intestines and liver of the toads using hematoxylin and eosin (H&E) stain and then examined under the binocular dissecting microscope. RESULTS: The concentration of aldrin in the intestine of A. regularis sampled at the dumpsites was higher than the concentrations in the intestines of A. regularis in the natural habitat. The concentrations of dieldrin in the uninfected A. regularis at both dumpsite and natural habitat were higher than the concentrations in the infected A. regularis at both environments. This indicated that the parasite Cosmocerca sp. may have played a depurative role in sequestering the concentration of dieldrin in the toads irrespective of the location. The parasites exhibited marked sequestration capacity characterized by the notably high total bioaccumulation rate both in the liver and the intestine at the dumpsite. The stunted villi being the common histological alteration in the infected and uninfected toads at the dumpsite but missing in the uninfected counterparts at the natural habitat may be attributed to the differences in the background concentration of the OCP congeners. CONCLUSIONS: The parasite- Cosmocerca sp. has been shown to be a potential tool in the biomonitoring of these OCP congeners which persists in the environment. Continuous research on these congeners is a searchlight to checkmate the environment to see how compliant industries and the consumers are in terms of regulation of these chemicals.

Dietary administration of ß-ionone epoxide to Sprague-Dawley rats for 90 days.

In a 90-day GLP-compliant study groups of Sprague-Dawley rats (10/sex/group) were fed diets containing ß-ionone epoxide, a fragrance material and a flavoring substance, at dietary concentrations providing target intakes of 0, 20, 40 and 80 mg/kg bw/day. There were no deaths and no adverse changes in clinical observations, ophthalmological examinations, body weight, body weight gain, food consumption, food efficiency; hematology, serum chemistry, urinalysis parameters; or in macroscopic findings attributable to ß-ionone epoxide administration. Increased absolute and relative liver weights in high dose females without correlating hepatic histopathological findings were considered non-adverse. Cortical vacuolation of adrenal zona fasciculata was observed in high-dose males but was considered non-adverse due to the nondegenerative nature of this alteration. ß-Ionone epoxide did not influence estrus cyclicity in females and did not affect sperm morphology or epididymal sperm count, homogenization-resistant spermatid count and motility measurements in male rats. The no-observed-adverse-effect level (NOAEL) for administration of ß-ionone epoxide in the diet was determined to be the highest dose tested of 80 mg/kg bw/day.

Sunscreens: UV filters to protect us: Part 1: Changing regulations and choices for optimal sun protection.

Sunscreens are topical preparations containing any number of ultraviolet filters (UVFs). The first part of the review will focus on the recent Food and Drug Administration (FDA) regulations of 2019 and general use of these agents. While sunscreen products are becoming more regulated in the United States, we still lag behind other countries in our options for UVFs. Sun protection to prevent skin cancer and aging changes should be a combination of sun avoidance, protective structures, and clothing as well as use of sunscreen products. Newer and safer products are needed to help supplement and replace older agents as well as improve their cosmetic acceptability. This will be a review of ingredients, local toxicities (i.e. contact dermatitis, photocontact dermatitis), special considerations for children, and cosmesis of sunscreen preparations. Part 2 will focus on the environmental, ecological and human toxicities that have been increasingly related to UVFs.

Sunscreens: UV filters to protect us: Part 2-Increasing awareness of UV filters and their potential toxicities to us and our environment.

BACKGROUND: Sunscreens are topical preparations containing one or more compounds that filter, block, reflect, scatter, or absorb ultraviolet (UV) light. Part 2 of this review focuses on the environmental, ecological effects and human toxicities that have been attributed to UV filters. METHODS: Literature review using NIH databases (eg, PubMed and Medline), FDA and EPA databases, Google Scholar, the Federal Register, and the Code of Federal Regulations (CFR). LIMITATIONS: This was a retrospective literature review that involved many different types of studies across a variety of species. Comparison between reports is limited by variations in methodology and criteria for toxicity. CONCLUSIONS: In vivo and in vitro studies on the environmental and biological effects of UV filters show a wide array of unanticipated adverse effects on the environment and exposed organisms. Coral bleaching receives considerable attention from the lay press, but the scientific literature identifies potential toxicities of endocrine, neurologic, neoplastic and developmental pathways. These effects harm a vast array of aquatic and marine biota, while almost no data supports human toxicity at currently used quantities (with the exception of contact allergy). Much of these data are from experimental studies or field observations; more controlled environmental studies and long-term human use data are limited. Several jurisdictions have prohibited specific UV filters, but this does not adequately address the dichotomy of the benefits of photoprotection vs lack of eco-friendly, safe, and FDA-approved alternatives.

Present cum future of SARS-CoV-2 virus and its associated control of virus-laden air pollutants leading to potential environmental threat - A global review.

The world is presently infected by the biological fever of COVID-19 caused by SARS-CoV-2 virus. The present study is mainly related to the airborne transmission of novel coronavirus through airway. Similarly, our mother planet is suffering from drastic effects of air pollution. There are sufficient probabilities or evidences proven for contagious virus transmission through polluted airborne-pathway in formed aerosol molecules. The pathways and sources of spread are detailed along with the best possible green control technologies or ideas to hinder further transmission. The combined effects of such root causes and unwanted outcomes are similar in nature leading to acute cardiac arrest of our planet. To maintain environmental sustainability, the prior future of such emerging unknown biological hazardous air emissions is to be thoroughly researched. So it is high time to deal with the future of hazardous air pollution and work on its preventive measures. The lifetime of such an airborne virus continues for several hours, thus imposing severe threat even during post-lockdown phase. The world waits eagerly for the development of successful vaccination or medication but the possible outcome is quite uncertain in terms of equivalent economy distribution and biomedical availability. Thus, risk assessments are to be carried out even during the post-vaccination period with proper environmental surveillance and monitoring. The skilled techniques of disinfection, sanitization, and other viable wayouts are to be modified with time, place, and prevailing climatic conditions, handling the pandemic efficiently. A healthy atmosphere makes the earth a better place to dwell, ensuring its future lifecycle.

Recent advances in process engineering and upcoming applications of metal-organic frameworks.

Progress in metal-organic frameworks (MOFs) has advanced from fundamental chemistry to engineering processes and applications, resulting in new industrial opportunities. The unique features of MOFs, such as their permanent porosity, high surface area, and structural flexibility, continue to draw industrial interest outside the traditional MOF field, both to solve existing challenges and to create new businesses. In this context, diverse research has been directed toward commercializing MOFs, but such studies have been performed according to a variety of individual goals. Therefore, there have been limited opportunities to share the challenges, goals, and findings with most of the MOF field. In this review, we examine the issues and demands for MOF commercialization and investigate recent advances in MOF process engineering and applications. Specifically, we discuss the criteria for MOF commercialization from the views of stability, producibility, regulations, and production cost. This review covers progress in the mass production and formation of MOFs along with future applications that are not currently well known but have high potential for new areas of MOF commercialization.

Temporary reduction in fine particulate matter due to 'anthropogenic emissions switch-off' during COVID-19 lockdown in Indian cities.

The COVID-19 pandemic elicited a global response to limit associated mortality, with social distancing and lockdowns being imposed. In India, human activities were restricted from late March 2020. This 'anthropogenic emissions switch-off' presented an opportunity to investigate impacts of COVID-19 mitigation measures on ambient air quality in five Indian cities (Chennai, Delhi, Hyderabad, Kolkata, and Mumbai), using in-situ measurements from 2015 to 2020. For each year, we isolated, analysed and compared fine particulate matter (PM2.5) concentration data from 25 March to 11 May, to elucidate the effects of the lockdown. Like other global cities, we observed substantial reductions in PM2.5 concentrations, from 19 to 43% (Chennai), 41-53% (Delhi), 26-54% (Hyderabad), 24-36% (Kolkata), and 10-39% (Mumbai). Generally, cities with larger traffic volumes showed greater reductions. Aerosol loading decreased by 29% (Chennai), 11% (Delhi), 4% (Kolkata), and 1% (Mumbai) against 2019 data. Health and related economic impact assessments indicated 630 prevented premature deaths during lockdown across all five cities, valued at 0.69 billion USD. Improvements in air quality may be considered a temporary lockdown benefit as revitalising the economy could reverse this trend. Regulatory bodies must closely monitor air quality levels, which currently offer a baseline for future mitigation plans.

Determination of cadmium and lead in tomato (Solanum lycopersicum) and lettuce (Lactuca sativa) consumed in Quito, Ecuador.

Vegetables are one of the most important components in the human diet, but despite their multiple nutritional components, studies have demonstrated the presence of trace metals in their edible parts. In Ecuador, two of the most consumed crops are tomato (Solanum lycopersicum) and lettuce (Lactuca sativa). The importance of these two crops in the Ecuadorian diet, especially in large and touristic locations like the Metropolitan District of Quito, implies food safety-related concerns for locals and visitors. However, no previous studies have quantified the cadmium and lead levels in these two vegetables using samples from Quito markets. Thus, the aim of this study was to determine the cadmium and lead content in both tomato and lettuce products from main nonorganic and organic markets in Quito using a graphite furnace atomic absorption spectrophotometer. The results showed that the cadmium levels were lower than 0.058 in tomatoes and 0.034 mg/kg in lettuce, which are under the respective threshold values (0.100 and 0.200 mg/kg). Regarding lead, levels lower than 0.066 mg/kg were detected in lettuce, which did not exceed the CXS 193-1995 threshold value, while levels in tomatoes were near or exceeded the threshold value (0.100 mg/kg) from four markets (0.209, 0.162, 0.110, 0.099 mg/kg), suggesting a possible risk from tomato consumption. In addition, most vegetables marketed as organic had higher metal content than those coming from nonorganic markets. Based on these results, local health and commercial control authorities should monitor contaminants in food products sold in Quito and other places in Ecuador to ensure their safety.

Effects of continuous exposure to low concentration of ClO2 gas on the growth, viability, and maintenance of undifferentiated MSCs in long-term cultures.

INTRODUCTION: Hygienic management is more important in the manufacturing of cell products than in the production of chemical agents, because cell material and final product cannot be decontaminated. On the other hand, especially in the selection of hygienic agent, the adverse effects on the cells must be considered as well as the decontamination effect. ClO2 is a potent disinfectant, which is now expected as a safe and effective hygienic agent in the field of cell production. In this study, we investigated the effects of low dose ClO2 gas in the atmosphere of CO2 incubator on the characteristics of MSCs cultured in it. METHODS: First, we installed a ClO2 generator to a CO2 incubator for cell culture in which a constant level of ClO2 can be maintained. After culturing human cord derived MSCs in the CO2 incubator, the characteristics of cells were analyzed. RESULTS: Continuous exposure to 0.05 ppmv of ClO2 gas did not affect cell proliferation until at least 8th passage. In the FACS analysis, antigens usually expressed on MSCs, CD105, CD90, CD44, CD73 and CD29, were positively observed, but differentiation markers, CD11b and CD34, were little expressed on the MSCs exposed to 0.05 ppmv or 0.1 ppmv of ClO2 gas just as on the control cells. Also in the investigation for cell death, 0.05 ppmv and 0.1 ppmv of ClO2 gas little affected the viability, apoptosis or necrosis of MSCs. Furthermore, we assessed senescence using SA-ß-gal staining. Although the frequency of stained cells cultured in 0.1 ppmv of ClO2 gas was significantly increased than that of not exposed cells, the stained cells in 0.05 ppmv were rare and their frequency was almost the same as that in control. CONCLUSIONS: All these results indicate that, although excessive concentration of ClO2 gas induces senescence but neither apoptosis nor cell differentiation, exposure to 0.05 ppmv of ClO2 gas little affected the characteristics of MSCs. In this study we demonstrate that continuous exposure to appropriate dose of ClO2 gas can be safely used as decontamination agent in cell processing facilities.

How good is a PCR efficiency estimate: Recommendations for precise and robust qPCR efficiency assessments.

We have examined the imprecision in the estimation of PCR efficiency by means of standard curves based on strategic experimental design with large number of technical replicates. In particular, how robust this estimation is in terms of a commonly varying factors: the instrument used, the number of technical replicates performed and the effect of the volume transferred throughout the dilution series. We used six different qPCR instruments, we performed 1-16 qPCR replicates per concentration and we tested 2-10 µl volume of analyte transferred, respectively. We find that the estimated PCR efficiency varies significantly across different instruments. Using a Monte Carlo approach, we find the uncertainty in the PCR efficiency estimation may be as large as 42.5% (95% CI) if standard curve with only one qPCR replicate is used in 16 different plates. Based on our investigation we propose recommendations for the precise estimation of PCR efficiency: (1) one robust standard curve with at least 3-4 qPCR replicates at each concentration shall be generated, (2) the efficiency is instrument dependent, but reproducibly stable on one platform, and (3) using a larger volume when constructing serial dilution series reduces sampling error and enables calibration across a wider dynamic range.

Exploring consumer exposure pathways and patterns of use for chemicals in the environment.

Humans are exposed to thousands of chemicals in the workplace, home, and via air, water, food, and soil. A major challenge in estimating chemical exposures is to understand which chemicals are present in these media and microenvironments. Here we describe the Chemical/Product Categories Database (CPCat), a new, publically available (http://actor.epa.gov/cpcat) database of information on chemicals mapped to "use categories" describing the usage or function of the chemical. CPCat was created by combining multiple and diverse sources of data on consumer- and industrial-process based chemical uses from regulatory agencies, manufacturers, and retailers in various countries. The database uses a controlled vocabulary of 833 terms and a novel nomenclature to capture and streamline descriptors of chemical use for 43,596 chemicals from the various sources. Examples of potential applications of CPCat are provided, including identifying chemicals to which children may be exposed and to support prioritization of chemicals for toxicity screening. CPCat is expected to be a valuable resource for regulators, risk assessors, and exposure scientists to identify potential sources of human exposures and exposure pathways, particularly for use in high-throughput chemical exposure assessment.

Can commonly-used fan-driven air cleaning technologies improve indoor air quality? A literature review.

Air cleaning techniques have been applied worldwide with the goal of improving indoor air quality. The effectiveness of applying these techniques varies widely, and pollutant removal efficiency is usually determined in controlled laboratory environments which may not be realized in practice. Some air cleaners are largely ineffective, and some produce harmful by-products. To summarize what is known regarding the effectiveness of fan-driven air cleaning technologies, a state-of-the-art review of the scientific literature was undertaken by a multidisciplinary panel of experts from Europe, North America, and Asia with expertise in air cleaning, aerosol science, medicine, chemistry and ventilation. The effects on health were not examined. Over 26,000 articles were identified in major literature databases; 400 were selected as being relevant based on their titles and abstracts by the first two authors, who further reduced the number of articles to 160 based on the full texts. These articles were reviewed by the panel using predefined inclusion criteria during their first meeting. Additions were also made by the panel. Of these, 133 articles were finally selected for detailed review. Each article was assessed independently by two members of the panel and then judged by the entire panel during a consensus meeting. During this process 59 articles were deemed conclusive and their results were used for final reporting at their second meeting. The conclusions are that: (1) None of the reviewed technologies was able to effectively remove all indoor pollutants and many were found to generate undesirable by-products during operation. (2) Particle filtration and sorption of gaseous pollutants were among the most effective air cleaning technologies, but there is insufficient information regarding long-term performance and proper maintenance. (3) The existing data make it difficult to extract information such as Clean Air Delivery Rate (CADR), which represents a common benchmark for comparing the performance of different air cleaning technologies. (4) To compare and select suitable indoor air cleaning devices, a labeling system accounting for characteristics such as CADR, energy consumption, volume, harmful by-products, and life span is necessary. For that purpose, a standard test room and condition should be built and studied. (5) Although there is evidence that some air cleaning technologies improve indoor air quality, further research is needed before any of them can be confidently recommended for use in indoor environments.