Characterization of atmospheric mercury from mercury-added product manufacturing using passive air samplers.

Although alternatives to mercury (Hg) are available in most products and industrial activities, Hg continues to be an ingredient in some products, including fluorescent lamps and electrical and electronic equipment (EEE). In this work, low-cost passive air samplers (PASs) were used to investigate the atmospheric Hg pollution in Zhongshan, a large industrial city and major hub of mercury-added product manufacturing in South China. The GEM concentrations in the atmosphere were measured for two weeks during the summer of 2019 at a total of 144 sites across Zhongshan. Comparison with the results of active sampling confirmed that the PASs yielded accurate and reliable gaseous elemental mercury (GEM) concentrations and were thus well-suited for multi-site field monitoring. The mean GEM concentrations in the areas with mercury-added product manufacturing activities (5.1 ± 0.4 ng m-3) were significantly higher than those in other parts of Zhongshan (1.5 ± 0.4 ng m-3), indicating that local releases, rather than regional transport, were responsible for the atmospheric Hg pollution. Elevated GEM concentrations (up to 11.4 ng m-3) were found in the vicinity of fluorescent lamp and EEE factories and workshops, indicating significant Hg vapor emissions, presumably from the outdated production technologies and non-standard operation by under-trained workers. The Hg emissions from mercury-added product manufacturing were estimated to be 0.06 and 7.8 t yr-1 for Zhongshan and China, respectively, based on the scales of fluorescent lamp and EEE production. The non-carcinogenic health risk of Zhongshan residents from inhalation and ingestion was judged acceptable, whereby the inhalation exposure in Hg-polluted areas exceeded that of dietary ingestion. These findings demonstrate that mercury-added product manufacturing still contributes notably to anthropogenic gaseous Hg releases in the industrial areas with intense mercury-added product manufacturing activities.

Environmental impact assessment of end-of-life fluorescent lamps in Rio de Janeiro, Brazil, under different recycling rate scenarios.

Fluorescent lamps are hazardous materials, as they contain toxic elements, which may lead to environmental contamination. Therefore, assessing potential environmental impacts arising from inadequate lamp disposal is paramount. Studies addressing the Life Cycle Analysis (LCA) of end-of-life fluorescent lamps are, however, still scarce, and inappropriate lamp disposal remains a matter of concern, especially in developing and underdeveloped countries. In Brazil, fluorescent lamps are still used countrywide and are often inadequately discarded. However, studies assessing fluorescent lamp impacts and potential impact reduction through enhanced recycling are still scarce in the country, despite Brazil's size and high waste generation rates. Furthermore, Brazil's lamp recycling program is a recent measure and still falls short of the country's needs. Thus, this study aimed to assess potential environmental impacts of end-of-life fluorescent lamps in Rio de Janeiro, the second largest capital in Brazil, to the best of our knowledge, for the first time. Potential impact reductions due to higher recycling program adherence considering 5, 20, 80 and 100 % recycling rates were also assessed. The findings indicate that the impact categories most influenced by end-of-life lamps were terrestrial ecotoxicity, human non-carcinogenic toxicity, global warming potential, and fossil resource scarcity. Increased recycling rates, in turn, reduced the environmental impact potential for all evaluated categories, reaching an almost 90 % reduction in most categories when applying a 100 % recycling rate. The current national program target recycling rate of 20 %, however, already contributes to an average impact reduction of over 70 %, comprising a more viable national application rate and already significantly contributing to reduced impacts.

Bio-removal of rare earth elements from hazardous industrial waste of CFL bulbs by the extremophile red alga Galdieria sulphuraria.

In recent decades, a shift has been seen in the use of light-emitting diodes over incandescent lights and compact fluorescent lamps (CFL), which eventually led to an increase in wastes of electrical equipment (WEE), especially fluorescent lamps (FLs) and CFL light bulbs. These widely used CFL lights, and their wastes are good sources of rare earth elements (REEs), which are desirable in almost every modern technology. Increased demand for REEs and their irregular supply have exerted pressure on us to seek alternative sources that may fulfill this demand in an eco-friendly manner. Bio-removal of wastes containing REEs, and their recycling may be a solution to this problem and could balance environmental and economic benefits. To address this problem, the current study focuses on the use of the extremophilic red alga, Galdieria sulphuraria, for bioaccumulation/removal of REEs from hazardous industrial wastes of CFL bulbs and the physiological response of a synchronized culture of G. sulphuraria. A CFL acid extract significantly affected growth, photosynthetic pigments, quantum yield, and cell cycle progression of this alga. A synchronous culture was able to efficiently accumulate REEs from a CFL acid extract and efficiency was increased by including two phytohormones, i.e., 6-Benzylaminopurine (BAP - Cytokinin family) and 1-Naphthaleneacetic acid (NAA - Auxin family).

Fluorescence and colorimetric LAMP-based real-time detection of human pathogenic Cryptosporidium spp. from environmental samples.

Public health concerns related to pathogenic protozoa are widespread, causing significant morbidity and mortality worldwide. Due to the lack of rapid and cost-effective diagnostic methods, timely treatment and control interventions are hindered. In this study, loop mediated isothermal amplification (LAMP) methods were optimised and evaluated for the rapid detection of human pathogenic Cryptosporidium species in environmental samples. Real-time fluorescence and colorimetric detection were tested simultaneously. As a reference method, the results were compared to the well-established droplet digital polymerase chain reaction (ddPCR) method. Both LAMP-based methods successfully detected the Cryptosporidium parvum (GP60 gene) and the entire Cryptosporidium genus (SAM gene) from environmental samples with 100% specificity and no cross-reactivity. Furthermore, both colorimetric and fluorescent methods demonstrated a high sensitivity, with the same limit of detection (LOD) of 1.1 copies of C. parvum per 25 µl reaction (0.02 ng/µl). For real-time fluorescence monitoring, the LAMP reaction can be completed within 28 min, and for visual detection, within 30 min. In addition, both fluorescent and colorimetric LAMP methods showed substantial agreement with the reference method (ddPCR) used. The developed protocols were able to detect C. parvum and Cryptosporidium spp. in 50-85% (n = 60) of environmental samples (treated and untreated wastewater, sludge, and surface water) compared to 58-98% (n = 60) detected by ddPCR. The results further demonstrate that LAMP is an efficient technique for detecting Cryptosporidium spp. in environmental samples due to its simplicity, low cost, sensitivity, and specificity. Therefore, it has great potential as a useful diagnostic tool for disease control and public health protection.

Clinical Validation of DNA Extraction-Free qPCR, Visual LAMP, and Fluorescent LAMP Assays for the Rapid Detection of African Swine Fever Virus.

The global pig industry and food safety are seriously threatened by outbreaks of African swine fever (ASF). To permit early diagnosis of African swine fever virus (ASFV), prevent its spread, and limit its outbreaks, a highly sensitive diagnostic method that can be performed at pig farms is required. Herein, we established DNA extraction-free real-time PCR (qPCR), visual loop-mediated isothermal amplification (LAMP), and fluorescent LAMP assays, which were compared with the results of World Organization for Animal Health (OIE) qPCR to assess ASFV-infected clinical samples. Based on plasmid DNA, the limit of detection for the three assays and OIE qPCR were 5.8 copies/µL. All four assays had good ASFV specificity and showed no cross-reactivity with other tested viruses. These assays were used to diagnose 100 clinical samples. The assays showed good diagnostic consistency, with kappa values of 1.0, 0.84, and 0.88, respectively. Compared with OIE qPCR, the diagnostic specificity/sensitivity of DNA extraction-free qPCR, visual LAMP, and fluorescent LAMP assays were 100%/100%, 100%/87.1%, and 100%/90.32%, respectively. The assays eliminated the need for DNA extraction and are more suitable for ASF diagnosis by inexperienced farmers in low-resource environments, making them a good choice for on-site monitoring of pig farms.

Urban mining of terbium, europium, and yttrium from real fluorescent lamp waste using supercritical fluid extraction: Process development and mechanistic investigation.

There is a significant global push towards recycling of waste electrical and electronic equipment (WEEE) to enable the circular economy. In this study an environmentally sustainable process using supercritical carbon dioxide as the solvent, along with a small volume of tributyl-phosphate-nitric acid (TBP-HNO3) adduct as the chelating agent, is developed to extract rare earth elements (REEs) from fluorescent lamp waste. It is found that mechanical activation using oscillation milling improves extraction efficiency. To elucidate the process mechanism, an in-depth characterization of solids before and after the process using transmission electron microscopy(TEM) and X-ray photoelectron spectroscopy (XPS)is performed. Furthermore, UV visible spectroscopy is performed to determine the coordination chemistry of the rare earths of interest, i.e., yttrium, europium, and terbium during the complexation with TBP-HNO3 adduct. It is found that Al3+ and Ca2+ cations from the aluminium oxide (Al2O3) and hydroxyapatite (Ca5(PO4)3OH) present in the fluorescent lamp waste compete with REEs in reacting with TBP-HNO3 adduct; hence, REE extractions from real fluorescent lamp waste is less than previously reported extractions from synthetic feeds. Not only can management of fluorescent lamp waste help conserve natural resources and protect ecosystems, but it can also facilitate efficient utilization of materials and promote the circular economy.

Hydrothermal Synthesis of Silicoaluminophosphate with AEL Structure Using a Residue of Fluorescent Lamps as Starting Material.

Silicoaluminophosphate molecular sieves of SAPO-11 type (AEL structure) were synthesized by the hydrothermal method, from the residue of a fluorescent lamp as a source or Si, Al, and P in the presence of water and di-propyamine (DPA) as an organic template. To adjust the P2O5/SiO2 and Si/Al and ratios, specific amounts of silica, alumina, or alumina hydroxide and orthophosphoric acid were added to obtain a gel with molar chemical composition 1.0 Al2O3:1.0 P2O5:1.2 DPA:0.3 SiO2:120 H2O. The syntheses were carried out at a temperature of 473 K at crystallization times of 24, 48, and 72 h. The fluorescent lamp residue and the obtained samples were characterized by X-ray fluorescence, X-ray diffraction, scanning electron microscopy, and BET surface area analysis using nitrogen adsorption isotherms. The presence of fluorapatite was detected as the main crystalline phase in the residue, jointly with considered amounts of silica, alumina, and phosphorus in oxide forms. The SAPO-11 prepared using aluminum hydroxide as Al source, P2O5/SiO2 molar ratio of 3.6 and Si/Al ratio of 0.14, at crystallization time of 72 h, achieves a yield of 75% with a surface area of 113 m2/g, showing that the residue from a fluorescent lamp is an alternative source for development of new materials based on Si, Al, and P.

Feasibility study of fluorescent lamp waste recycling by thermal desorption.

The proposed Minamata Convention ban on the use of fluorescent lamps at the end of 2020, with a consequent reduction in mercury (Hg) light products, is expected to produce large amounts of discarded fluorescent bulbs. In this context, the most effective recycling options are a thermal mercury recovery system and/or aqueous solution leaching (lixiviation) to recover rare earth elements (REEs). Due to the heterogeneous nature of these wastes, a complete characterization of Hg compounds in addition to a determination of their desorption temperatures is required for their recycling. The objective of this study is to assess the feasibility of a fast cost-effective thermal characterization to ameliorate recycling treatments. A pyrolysis heating system with a heat ramping capability combined with atomic absorption spectrometry makes it possible to obtain residue data with regard to the temperature ranges needed to achieve total Hg desorption. The major drawback of these heat treatments has been the amount of Hg absorbed from the residue by the glass matrices, ranging from 23.4 to 39.1% in the samples studied. Meanwhile, it has been estimated that 70% of Hg is recovered at a temperature of 437 °C.

Light emitting diodes optimisation for secondary metabolites production by Droseraceae plants.

The most abundant active compound in Droseraceae is plumbagin, a naphthoquinone widely used for medical purposes due to its antimicrobial, antitussive, antimalarial and anticancer properties. In this work, we created a light-emitting diode (LED) based culture illumination setup as an alternative to fluorescent lamps traditionally used as a light source in plant in vitro cultures. The plants of Drosera binata and Drosera peltata cultured under LED illumination grew equally well and produced similar amounts of biologically active compounds as plants grown under fluorescent lamps. The plants were cultured on two media differing in mineral composition, sucrose content and pH. Secondary metabolites were extracted with ethanol from the plants after harvesting. The extracts were subjected to HPLC and microbiological analyses. We observed differences in morphology and secondary metabolism between plants of the same species grown on different media. However, we did not note significant changes in secondary metabolite yield under assessed lighting conditions. We propose LEDs as a more efficient, eco-friendly and economically reasonable source of light for big scale in vitro production of plumbagin in Drosera species than fluorescent lamps.

Effects of Nocturnal UV-B Irradiation on Growth, Flowering, and Phytochemical Concentration in Leaves of Greenhouse-Grown Red Perilla.

In Japan, red perilla leaves are used in the food and coloring industries, as well as in crude medicine. Perilla leaves contain a high concentration of phytochemicals such as perillaldehyde (PA) and rosmarinic acid (RA). The effects of UV-B radiation intensity (0.05-0.2 W m-2, UV-BBE: 0.041-0.083 W m-2), duration (3 or 6 h), and irradiation method (continuous or intermittent) for artificial nocturnal lighting using UV-B fluorescent lamps were evaluated on growth, flowering, and leaf phytochemical concentration in greenhouse-grown perilla. Under continuous UV-B irradiation at 0.1 W m-2 for 3 or 6 h, leaf color changed from red to green and leaf fresh weight decreased, compared with the control treatment. No leaf color change was observed under the 3-h treatment with UV-B radiation at 0.05 W m-2, wherein leaf fresh weight was similar to that of the control. Furthermore, RA concentration under continuous UV-B irradiation at 0.05 W m-2 for 3 h increased two-fold compared to that under control treatment, while PA concentration was not affected by UV-B irradiation. Thus, our data showed that continuous UV-B irradiation at 0.05 W m-2 for 3 h could effectively produce RA-rich perilla leaves without reducing in phenotypic quality or productivity. However, a 6-h intermittent illumination inhibited flowering without altering phytochemical concentration.

Modified compact fluorescent lamps improve light-induced off-season floral stimulation in dragon fruit farming.

Efficient light-induced floral stimulation plays a key role in energy conservation and maintaining stable productivity during off-season periods of dragon fruit plants. In this study, we first reported on results of a survey on dragon fruit farmers regarding use of lamps in performing artificially induced flowering process in Vietnam. It was found that the use of incandescent lamp was prevalent in dragon fruit cultivation practices, resulting in heavy electricity consumption, and that low-power compact fluorescent light (CFL) bulbs were not extensively utilized, possibly due to low floral induction performance of domestic CFL bulbs. Arguing that emission spectra of currently used lamps were not consistent with adsorption spectra of phytochromes, whose transformation is responsible for flowering process of dragon fruit, we then proposed three improved CFL lamps (power capacity of 20 W) having emission spectra focused on red and far-red regions. New lamp prototypes were tested in 7 field experiments in three different provinces in Vietnam. One improved CFL bulb (treatment 2) performed relatively well in comparison with the incandescent control lamp (60 W) in six out of seven experiments with regard to some growth indicators (e.g., number of floral stems, number of bubs, number of fruits per plant) and fruit yield. Recent success on commercialization of the improved CFL lamp demonstrates the potential of CFL lamps in floral stimulating irradiation of other crops and plants and in alleviating electricity burden in dragon fruit growing areas.

Rationally designed dipicolinate-functionalized silica for highly efficient recovery of rare-earth elements from e-waste.

Composition of the immobilized layer plays a crucial role in metal adsorption properties of complexing organo-mineral materials. Ignoring the specific features of chemical reactions on solid surface can lead to a significant deterioration in the target properties of the resulted materials. In this research we demonstrated that rationally designed surface-assembling synthesis of organo-silica with covalently immobilized fragments of dipicolinic acid (DPA) resulted in the adsorbent that is capable quantitively recover almost all Rare Earth elements (REEs) from multielement solution with pH > 1.7. In ten consecutive adsorption/desorption cycles no noticeable loss of its efficiency was found, with a mean value of REEs recovery larger than 97%. The adsorbent has been used to recover REEs from model solutions (22 metal ions in 0.5 mol L-1 NaCl) and real leaching solution of waste of fluorescent lamps. It was demonstrated that even 3200-fold excess of Fe and Cu ions only slightly reduces REEs recovery. The adsorbent is capable to recover above 80% of all (except La) REEs from acidic leaching solution from fluorescent lamps with enrichment factors above 600. After adsorption of Eu3+ and Tb3+, the resulting materials exhibited strong red and green luminescence, respectively, indicating chelating mechanism of REEs adsorption on SiO2-DPA.

Rapid, Affordable, and Scalable SARS-CoV-2 Detection From Saliva.

Here we present an inexpensive, rapid, and robust reverse-transcription loop-mediated isothermal amplification (RT-LAMP)-based severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) detection method that is easily scalable, enabling point-of-care facilities and clinical labs to determine results from patients' saliva directly in 30 minutes for less than $2 per reaction. The method uses a novel combination of widely available reagents that can be prepared in bulk, plated, and frozen and remain stable until samples are received. This innovation dramatically reduces preparation time, enabling high-throughput automation and testing with time to results (including setup) in less than 1 hour for 96 patient samples simultaneously when using a 384-well format. By using a dual reporter (phenol red pH indicator for end-point detection and SYTO-9 fluorescent dye for real time), the assay also provides internal validation of results and redundancy in the event of an instrument malfunction.

Atmospheric mercury pollution caused by fluorescent lamp manufacturing and the associated human health risk in a large industrial and commercial city.

Although already eliminated in most industrial processes, mercury, as an essential ingredient in all energy-efficient lighting technologies, is still used in fluorescent lamp manufacturing. This study was conducted to investigate the atmospheric pollution caused by fluorescent lamp production and assess the associated public health risk in a large industrial and commercial city of south China, Zhongshan, which is a major production hub of lighting products. Concentrations of total gaseous mercury (TGM) in the atmosphere were measured over a total of 342 sites in the industrial, commercial, and residential areas. The average levels of TGM in the industrial, commercial, and residential areas prior to the landing of a typhoon were 12 ± 11, 3.6 ± 2.1, and 2.7 ± 1.3 ng⋅m-3, respectively. TGM concentrations in the industrial areas exhibited significant diurnal variation, with levels in the working hours being much higher than those in the non-working hours, which indicates that the high atmospheric mercury concentrations were contributed by local emissions, instead of regional transport. Most fluorescent lamp manufacturing activities in the city were shut down during a typhoon event, which resulted in a significant reduction in the average TGM level (down to 1.6 ± 1.8 ng⋅m-3) and rendered the difference in the average TGM levels in the industrial areas no longer significant between the working and non-working hours. Elevated TGM levels (up to 49 ng⋅m-3) were found near clusters of small-scale fluorescent lamp workshops in both industrial and commercial areas, which is indicative of significant emissions of mercury vapor resulting from obsolete equipment and production technologies. No significant non-carcinogenic risk was found for the general residents in the sampling area over the study period, while the risk for the workers in the fluorescent lamp manufacturing facilities and workshops could be higher. These findings indicate that fluorescent lamp manufacturing in the developing countries is a major source of atmospheric mercury.

Conocimientos, actitudes y prácticas sobre la adherencia al lavado de manos en personal de salud / Knowledge, attitudes and practices related to the adherence of handwashing in health personnel

Introducción: El lavado de manos deficiente, sigue siendo un problema hospitalario. Cumplir con las recomendaciones internacionales ofrece seguridad en el cuidado. Objetivo: Identificar el nivel de conocimiento, actitudes y prácticas en la técnica del lavado de manos en personal de salud en un hospital pediátrico de La Habana. Metodología: Estudio descriptivo a 145 trabajadores (31,7 por ciento médicos, 35,2 por ciento enfermeros, 22,8 por ciento médicos residentes y 10,3 por ciento estudiantes). De 13 servicios el cuerpo de guardia, sala de respiratorio, cirugía, neurocirugía y quemados, fueron los que más participación tuvieron. El estudio se realizó en tres etapas: 1. Observación directa de la técnica del lavado de manos. 2. Observación de la calidad del lavado de manos mediante lámpara fluorescente. 3. Medida del conocimiento acerca del lavado de manos y actitud mediante encuesta. Resultados: En la primera etapa, el 51,7 por ciento calificó de inadecuado, en la segunda etapa el 64,8 por ciento también tuvo una evaluación inadecuada y en las encuestas, el conocimiento alcanzó solo 52,4 por ciento, considerado inapropiado. La actitud ante esta actividad fue calificada de inadecuado en el 53,1 por ciento, con un mejor porcentaje en el personal de enfermería. Conclusiones: Los conocimientos, actitudes y prácticas sobre el lavado de manos es deficiente, por lo que debe diseñarse un programa de capacitación en todos los niveles, sea pregrado, posgrado o formación continua, donde exista responsabilidad individual de cada profesional sanitario, y se insista en ello(AU)

Introduction: Deficient handwashing is still a problem in hospitals. The compliance of the international recommendations on this matter provides security in the care. Objective: To identify the level of knowledge, attitudes and practices in the technique of handwashing in a pediatric hospital in Havana. Methodology: Descriptive study applied to 145 workers (31.7 percent doctors, 35.2 percent nurses, 22.8 percent residents, and 10.3 percent students) of 13 services. Emergencies, Respiratory, Surgery, Neurosurgery and Caumatology were the services with more participation. The study was conducted in three stages: 1. Direct observation of the technique of handwashing. 2. Quality observation of the handwashing using fluorescent lamp. 3. Extent of knowledge on handwashing and attitudes through survey. Results: In the first stage, the 51.7 percent the handwashing was assessed as inappropriate, in the second stage the 64.8 percent was also evaluated as inadequate, and in the surveys, the 52.4 percent had an incorrect knowledge; the attitude towards this activity was described as inappropriate in the 53.1 percent , with a better percentage in the nursing staff. Conclusions: The knowledge, attitudes and practices on handwashing were poor, so it must be designed a training program at all levels, whether undergraduate, graduate or continuing training, where individual responsibility of each healthcare professional exists, and should be highlithed(AU)

Organic and Inorganic Mercury in Biological Samples of Flouresecent Lamp Industries Workers and Health Risks.

OBJECTIVE: The present study aims to investigate the concentrations of Hg and its aspects methyl mercury (Me-Hg) and inorganic mercury (I-Hg) in the biological samples (BSs) of fluorescent lamp industries workers (FLIWs). METHODOLOGY: Different BSs including red blood cells (RBCs), plasma, urine, hair and nails were collected from the workers exposed to Hg and unexposed persons were selected as control group to measure both the T-Hg concentration as well as its species in different biological samples through quantitative analysis. Health data was collected through questionnaire survey. RESULTS: The mean concentrations of T-Hg (31.9 µg/L), Me-Hg (27.7 µg/L), and I-Hg (5.36 µg/L) in RBCs were found significantly ( P < 0.001) higher among the workers ( n = 40) as compared to the control group ( n = 40). Similarly the mean Hg concentrations in plasma, urine, hair and nails were also significantly higher among the workers than the control group. The statistical relation between Hg concentration and demographic characteristics observed that workers experience and fish consumption has increased the Hg concentration while age, weight and smoking found no significant effect on Hg concentration in the BSs. CONCLUSION: The study observed that the workers were highly exposed to high concentration of Hg and they are at a high health risk.

Organic and Inorganic Mercury in Biological Samples of Flouresecent Lamp Industries Workers and Health Risks / 生物医学与环境科学（英文）

Objective@#The present study aims to investigate the concentrations of Hg and its aspects methyl mercury (Me-Hg) and inorganic mercury (I-Hg) in the biological samples (BSs) of fluorescent lamp industries workers (FLIWs).@*Methodology@#Different BSs including red blood cells (RBCs), plasma, urine, hair and nails were collected from the workers exposed to Hg and unexposed persons were selected as control group to measure both the T-Hg concentration as well as its species in different biological samples through quantitative analysis. Health data was collected through questionnaire survey.@*Results@#The mean concentrations of T-Hg (31.9 µg/L), Me-Hg (27.7 µg/L), and I-Hg (5.36 µg/L) in RBCs were found significantly ( < 0.001) higher among the workers ( = 40) as compared to the control group ( = 40). Similarly the mean Hg concentrations in plasma, urine, hair and nails were also significantly higher among the workers than the control group. The statistical relation between Hg concentration and demographic characteristics observed that workers experience and fish consumption has increased the Hg concentration while age, weight and smoking found no significant effect on Hg concentration in the BSs.@*Conclusion@#The study observed that the workers were highly exposed to high concentration of Hg and they are at a high health risk.

Study of the influence of wavelengths and intensities of LEDs on the growth, photosynthetic pigment, and volatile compounds production of Lippia rotundifolia Cham in vitro.

Lippia rotundifolia Cham. is in the family Verbenaceae and is endemic to the Cerrado. This species is aromatic and characterized by the presence of glandular trichomes on its leaves that are rich in monoterpenes. The objective of this study was to evaluate the growth, photosynthetic pigment production, and chemical composition of L. rotundifolia grown in vitro under different light wavelengths and intensities. The light intensities consisted of five treatments using cool white fluorescent lamps at 20, 54, 78, 88, and 110 µmol m-2 s-1. The light quality consisted of six treatments using light-emitting diodes (LEDs) in different light wavelengths, namely, white, red, blue, and their interactions: 1R:1B, 2.5R:1B, and 1R:2.5B. After 45 days, the biometric parameters, photosynthetic pigment content, and volatile compounds were evaluated. The lower light intensities of 20 and 54 µmol m-2 s-1 generated higher growth, photosynthetic pigment content, and biomass accumulation. Myrcene and pentadecane were highest under light intensities of 88 and 110 µmol m-2 s-1, respectively. The highest limonene and ocimenone levels were obtained at 20 and 54 µmol m-2 s-1 intensity, respectively, and the highest myrcenone content was obtained at 78 µmol m-2 s-1 intensity. Regarding the light wavelengths, the combination of red and blue spectra further stimulated plantlet growth, and the 2.5R:1B combination obtained the best biometric data and total chlorophyll content. The z-ocimenone chemical compound contents were highest under the 1R:2.5B light spectrum. The monochromatic blue spectrum increased the myrcene and limonene content but decreased the myrcenone content, which was increased by red light. The highest pentadecane contents were obtained with the white spectrum and the red and blue combinations.

Improving the work environment in the fluorescent lamp recycling sector by optimizing mercury elimination.

One of the main issues in the fluorescent lamp recycling sector is the mercury contamination of output fractions and occupational exposure associated with recycling operations. The aim of this study is to carry out effective mercury mass balance determinations and improve mercury recovery by finding the optimal levels for the recycling process parameters. These optimizations will allow upstream mercury emissions to be reduced, which will help to avoid mercury exposure among WEEE recycling workers. Firstly, the distribution of mercury was assessed in new and spent lamps. For new fluorescent tubes, the mean percentage of mercury in the solid phase is lower in new fluorescent tubes (19.5% with 5.5% in glass, 9.7% in end caps and 4.3% in luminescent powder) than in spent tubes (33.3% with 8.3% in glass, 12.9% in end caps and 12.1% in luminescent powder). The parametric study also shows that the finer the grains of glass, the higher the concentration of mercury (1.2 µg Hg/g for glass size particle >1000 µm and 152.0 µg Hg/g for glass size particle <100 µm); the crushing time required for the optimal removal of mercury from spent tubes is 24 h; on average 71% of the mercury is desorbed at a temperature of 400 °C. The effects of air flow rate, rotation speed and number of balls could not be determined due to wide variations in the results. It is recommended that recycling companies employ processes combining as heating and mixing techniques for the recovery of mercury from lamps in order to both (i) remove as much of the mercury as possible in vapor form and (ii) avoid adsorption of the mercury at new sites created during the crushing process.

Cases of acute mercury poisoning by mercury vapor exposure during the demolition of a fluorescent lamp factory.

BACKGROUND: In 2015, workers dismantling a fluorescent lamp factory in Korea were affected by mercury poisoning from exposure to mercury vapor. CASE PRESENTATION: Eighteen out of the 21 workers who participated in the demolition project presented with symptoms of poisoning and, of these, 10 had persistent symptoms even at 18 months after the initial exposure to mercury vapor. Early symptoms of 18 workers included a general skin rash, pruritus, myalgia, sleep disturbance, and cough and sputum production. Following alleviation of these initial symptoms, late symptoms, such as easy fatigue, insomnia, bad dreams, and anxiety disorder, began to manifest in 10 out of 18 patients. Seven workers underwent psychiatric care owing to sleep disturbance, anxiety disorder, and depression, and three workers underwent dermatologic treatment for hyperpigmentation, erythematous skin eruption, and chloracne-like skin lesions. Furthermore, three workers developed a coarse jerky movement, two had swan neck deformity of the fingers, and two received care at an anesthesiology clinic for paresthesia, such as burning sensation, cold sensation, and pain. Two workers underwent urologic treatment for dysfunction of the urologic system and impotence. However, symptomatic treatment did not result in satisfactory relief of these symptoms. CONCLUSION: Awareness of the perils of mercury and prevention of mercury exposure are critical for preventing health hazards caused by mercury vapor. Chelation therapy should be performed promptly following mercury poisoning to minimize damage.