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Safety and Health At Work Dec 2020Research on the status of many chemicals used in the semiconductor industry is needed. The purpose of this study was to describe the overall status of chemical use in...
BACKGROUND
Research on the status of many chemicals used in the semiconductor industry is needed. The purpose of this study was to describe the overall status of chemical use in the semiconductor industry in Korea and to examine it from a health perspective.
METHODS
Data on the status of chemical use and safety data sheets at 11 of 12 major semiconductor workplaces in Korea were collected. The number of chemical products and chemical constituents, quantities of chemicals, and trade secret ingredients used, as well as the health hazards were examined.
RESULTS
On average, 210 chemical products and 135 chemical constituents were used at the surveyed workplaces. Among all chemical products, 33% (range: 16-56%) contained at least one trade secret ingredient. Most of the trade secret ingredients were used in the photolithography process. Several carcinogens, including sulfuric acid, chromic acid, ethylene oxide, crystalline silica, potassium dichromate, and formaldehyde were also used. Only 29% (39 of 135) of the chemical constituents had occupational exposure limits, and more than 60% had no National Fire Protection Association health, safety, and reactivity ratings. Based on the aforementioned results, this study revealed the following. First, many chemical products and constituents are being used in the semiconductor industry and many products contained trade secret ingredients. Second, many products contained significant amounts of carcinogenic, mutagenic, and reproductive toxicant materials.
CONCLUSION
We conclude that protecting workers in the semiconductor industry against harm from chemical substances will be difficult, due to widespread use of trade secret ingredients and a lack of hazard information. The findings of the status of chemical use and the health and safety risks in semiconductor industry will contribute to epidemiological studies, safe workplace, and worker health protection.
PubMed: 33329917
DOI: 10.1016/j.shaw.2020.04.005 -
Animals : An Open Access Journal From... Jan 2024The tadpole shrimp is a freshwater crustacean with fast embryonic and larval development, short life cycle, and high fecundity. They are very active swimmers of a...
The tadpole shrimp is a freshwater crustacean with fast embryonic and larval development, short life cycle, and high fecundity. They are very active swimmers of a reasonable size, easy to spot and record. Such characteristics make it a promising candidate as an experimental model in ecotoxicology to evaluate the effects of aquatic pollutants, particularly using its locomotor behavior as an endpoint. To evaluate the sensitivity of and develop endpoints of interest, we conducted exposure experiments with lethal and sub-lethal concentrations of potassium dichromate, a compound known for its ecotoxicological importance and as a hexavalent chromium source. The endpoints evaluated were mortality, growth, sexual maturation, reproductive output, cholinesterase activity and locomotor/swimming behavior. The 96 h median lethal concentration was found to be 65 µg/L. Furthermore, exposure to potassium dichromate at higher concentrations had a significant negative impact on the growth rate of in terms of both body mass and length. The time for maturation was also delayed at higher concentrations. In addition, locomotor behavior allowed for the discrimination of all tested chromium concentrations and the control group and from each other, proving to be the most sensitive endpoint. Overall, the data support the potential of as a model for ecotoxicity testing, using apical endpoints with impact at the population level; in particular, results suggest that behavior assessments in this species might be useful for detecting hazardous compounds in environmental monitoring of freshwater ecosystems.
PubMed: 38338000
DOI: 10.3390/ani14030358 -
Saudi Journal of Biological Sciences Dec 2020The present study aimed to analyze the nephroprotective property of violacein obtained from the bacterium, . The nephrotoxicity in the animal model was induced by...
The present study aimed to analyze the nephroprotective property of violacein obtained from the bacterium, . The nephrotoxicity in the animal model was induced by gentamicin, potassium dichromate, mercuric chloride, and cadmium chloride-induced nephrotoxicity in the Wistar rats was analyzed by measuring the serum creatinine, uric acid, and urea level. The present investigation revealed the nephroprotective property on convoluted proximal tubule (S1 and S2 segments) and the straight proximal tubule (S3 segment). Also, violacein significantly improved the renal function by the renal protective property on S2 segment of proximal tubule from the nephrotoxicity stimulated by mercuric chloride, potassium dichromate, cadmium chloride and gentamicin in animal models. Animal model studies revealed that violacein at 20 and 40 mg/kg p.o improved the renal function and significantly reduced the increased amount of uric acid, creatinine, and blood urea compared to the control.
PubMed: 33304136
DOI: 10.1016/j.sjbs.2020.10.004 -
Actas Dermo-sifiliograficas Mar 2022Hand eczema is common in patients with atopic dermatitis (AD), but few studies have described the characteristics of these patients in large, representative populations...
BACKGROUND
Hand eczema is common in patients with atopic dermatitis (AD), but few studies have described the characteristics of these patients in large, representative populations from different geographic regions and occupational settings.
OBJECTIVE
To describe the epidemiological, clinical, and allergy profile of patients with hand eczema who underwent patch testing and compare patients with and without AD.
METHODS
Analysis of data from the Spanish Contact Dermatitis Registry, a multicenter registry of patients who undergo patch testing in Spain.
RESULTS
We included 1466 patients with hand eczema who were patch tested between January 2018 and June 2020. Those with AD were younger and had had symptoms for longer before testing. They were also more likely to have been exposed to occupational triggers (38% vs 53% for patients without AD). The only profession for which significant differences were found was hairdressing. The most common allergens were nickel sulfate, methylchloroisothiazolinone/methylisothiazolinone, cobalt chloride, potassium dichromate, fragrance mixes I and II, and formaldehyde. The most common diagnoses were allergic contact dermatitis (24% vs 31% in patients with and without AD, P=.0224) and irritant contact dermatitis (18% and 35% respectively, P<.001).
CONCLUSIONS
AD is common in patients with predominant hand eczema who undergo patch testing. Patients with hand eczema and AD have different clinical and epidemiological characteristics to hand eczema patients in general and their final diagnosis following patch testing is also different.
Topics: Allergens; Dermatitis, Allergic Contact; Dermatitis, Atopic; Eczema; Hand Dermatoses; Humans; Patch Tests; Registries; Retrospective Studies
PubMed: 35526918
DOI: 10.1016/j.ad.2021.10.002 -
Journal of Dairy Science Oct 1982A rapid procedure is described for measuring casein in milk by a combination of isoelectric precipitation and amido black dye-binding. Individual milk samples from 38... (Comparative Study)
Comparative Study
A rapid procedure is described for measuring casein in milk by a combination of isoelectric precipitation and amido black dye-binding. Individual milk samples from 38 cows were subsampled, preserved with potassium dichromate at a concentration of 8 mg/ml of milk, and analyzed for fat and protein by the Milko-Scan 300 and for protein and casein by the dye-binding procedure on day 1, 4, 7, and 10 after milk collection. Fat tests were not affected by sample storage time, but protein tests showed variation depending on the interval between milk sample collection and analysis. In a separate study effects of potassium dichromate used as a preservative at 0, 2, 4, 6, 8, and 12 mg/ml of milk on chemical determinations were investigated. No changes were significant in fat and protein analyzed by the infrared method for concentrations of preservative. There were no significant differences in protein determination by the two methods for nonpreserved samples. For preserved samples, the dye-binding method for protein gave determinations higher than those by the infrared method. The difference increased linearly with increasing concentration of potassium dichromate at .07% in protein for every 2 mg of potassium dichromate per milliliter of milk.
Topics: Animals; Caseins; Cattle; Chromates; Food Analysis; Food Preservation; Lipid Metabolism; Milk; Milk Proteins; Potassium Dichromate; Time Factors
PubMed: 7174958
DOI: 10.3168/jds.S0022-0302(82)82435-1 -
Revista Brasileira de Parasitologia... 2022The objectives of the present study were: (1) to determine the prevalence of Eimeria spp. sporulated oocysts in calves from 26 Municipalities in the Central Zone of the...
The objectives of the present study were: (1) to determine the prevalence of Eimeria spp. sporulated oocysts in calves from 26 Municipalities in the Central Zone of the State of Veracruz, Mexico, (2) to identify the Eimeria spp. infecting calves, and (3) to identify the risk factors associated with the presence of Eimeria spp. in tropical cattle. A total of 930 individual fecal samples were analyzed by using the McMaster technique; then, oocysts were maintained in 2.5% potassium dichromate to allow sporulation. The general prevalence of calves with Eimeria spp. oocysts was 39.7% (370/930). Of a total of 10 identified species, Eimeria canadensis was the most observed, followed by Eimeria bovis and Eimeria zuernii. The statistical analysis showed an association between the age of the calves (5 to 9 months), the presence of other animals, the physiographic regions and the restricted type of husbandry with the presence of Eimeria spp. in calves (P<0.05). Protective risk factors, such as: routine coprological analysis was also associated with a decrease in infection. These data demonstrate the presence of coccidia in cattle from the State of Veracruz, additionally to the necessary measures that must be taken to control this parasitosis.
Topics: Animals; Cattle; Cattle Diseases; Coccidiosis; Eimeria; Feces; Mexico; Oocysts; Prevalence; Risk Factors
PubMed: 35946612
DOI: 10.1590/S1984-29612022043 -
Biological Trace Element Research Nov 2023Lactoferrin (LCF), a potent naturally occurring antioxidant, is a crucial component in preventing potassium dichromate (PDC) toxicity. The goal of the current work was...
Lactoferrin (LCF), a potent naturally occurring antioxidant, is a crucial component in preventing potassium dichromate (PDC) toxicity. The goal of the current work was to study the potential efficacy of LCF in preventing PDC(CrVI)-induced testicular toxicity and oxidative injury in rats. Six groups of male rats of Wistar stain were randomly categorized into: group 1, which served as the control; group 2 and 3 received LCF (200 and 300 mg/kg orally, respectively); group 4 received PDC (2 mg/kg i.p.); group 5 and 6 pretreated with LCF, followed by PDC as in group 4 with 90 min apart for 28 days. PDC-intoxicated rats showed a significantly altered spermogram with abnormal sperm morphology. PDC significantly upregulated serum FSH and downregulated testosterone levels. Additionally, PDC decreased the levels of testicular key antioxidant biomarkers (catalase (CAT), superoxide dismutase (SOD), and glutathione (GSH)) with elevated lipid peroxidation marker (TBARS) and testicular chromium content. Moreover, it upregulated testicular proinflammatory cytokines, IL-1, IL-6, IL-10, and TNF-α, induced histopathological changes in testes with significant immunohistochemical expression of FasL and moderate expression of Nrf2. Pretreatment with LCF significantly mitigated PDC-induced testicular toxicity by enhancing spermogram, improving hormonal levels, restoring testicular oxidant/antioxidant balance, and decreasing testicular IL-1, IL6, IL-10, and TNFα levels, and amending both FasL and Nrf2 immunohistochemical-expression. Additionally, LCF improved testicular histopathological picture and spermatogenesis. Our results highlight the importance of LCF as a superior protective modulator of PDC-induced testicular injury.
Topics: Rats; Male; Animals; Testis; Antioxidants; Lactoferrin; Interleukin-10; Chromium; NF-E2-Related Factor 2; Rats, Wistar; Semen; Oxidative Stress; Glutathione; Potassium Dichromate; Interleukin-1
PubMed: 36877398
DOI: 10.1007/s12011-023-03605-3 -
Animals : An Open Access Journal From... Jan 2022This study was conducted to investigate the molecular mechanisms of selenium (Se) antagonism of hexavalent chromium (Cr)-induced toxicity. Potassium dichromate (KCrO)...
This study was conducted to investigate the molecular mechanisms of selenium (Se) antagonism of hexavalent chromium (Cr)-induced toxicity. Potassium dichromate (KCrO) and selenium-enriched yeast (SeY) were used to construct the single Cr and combined Se/Cr exposure broiler models, and then the broilers were randomly divided into four groups (C group, Se group, Se/Cr group, and Cr group). After a 42-day experiment, the spleen tissues of broilers were excised and weighted. The antagonistic mechanisms of Se and Cr were evaluated using histopathological assessment, serum biochemical tests, oxidative stress kits, ELISA, qPCR, and Western blotting. On the whole, there were no significant changes between the C and Se groups. The spleen organ index in the Cr group was significantly decreased, but SeY increased spleen organ index to a certain extent. The levels of SOD and GSH were reduced, and the MDA content was elevated by Cr; however, these changes were mitigated by Se/Cr exposure. Importantly, Cr exposure induced a series of histopathological injuries in broiler spleen tissues, while these symptoms were significantly relieved in the Se/Crgroup. Furthermore, Cr significantly decreased the levels of T-globulin, IgA, IgM, and IgG in serum. Contrarily, dramatically more T-globulin IgA, IgM, and IgG were found in the Se/Crgroup than in the Cr group. Revealed by the results of qPCR and WB, the expressions of NF-κB, IκBα, and p-IκBα were upregulated in Cr groups, while they were downregulated in Se/Cr group compared to that in Cr group. Besides IFN-γ and IL-2, the expressions of pro-inflammatory cytokines were significantly increased by Cr exposure, but the SeY supplement relived the expression levels mediated by Cr exposure. In conclusion, our findings suggest SeY has biological activity that can protect broiler spleens from immunosuppression and inflammation induced by Cr, and we speculate that the NF-κB signaling pathway is one of its mechanisms.
PubMed: 35049769
DOI: 10.3390/ani12020146 -
Toxicology Jan 2018According to the new EU Medical Devices (MDR) legislation coming into effect in 2017, manufactures will have to comply with higher standards of quality and safety for...
According to the new EU Medical Devices (MDR) legislation coming into effect in 2017, manufactures will have to comply with higher standards of quality and safety for medical devices in order to meet common safety concerns regarding such products. Metal alloys are extensively used in dentistry and medicine (e.g. orthopedic surgery and cardiology) even though clinical experience suggests that many metals are sensitizers. The aim of this study was to further test the applicability domain of the in vitro reconstructed human epidermis (RhE) IL-18 assay developed to identify contact allergens and in doing so: i) determine whether different metal salts, representing leachables from metal alloys used in medical devices, could be correctly labelled and classified; and ii) assess the ability of different salts for the same metal to penetrate the skin stratum corneum. Twenty eight chemicals including 15 metal salts were topically exposed to RhE. Nickel, chrome, gold, palladium were each tested in two different salt forms, and titanium in 4 different salt forms. Metal salts were labelled (YES/NO) as sensitizer if a threshold of more than 5 fold IL18 release was reached. The in vitro estimation of expected sensitization induction level (potency) was assessed by interpolating in vitro EC50 and IL-18 SI2 with LLNA EC3 and human NOEL values from standard reference curves generated using DNCB (extreme) and benzocaine (weak). Metal salts, in contrast to other chemical sensitizers and with the exception of potassium dichromate (VI) and cobalt (II) chloride, were not identified as contact allergens since they only induced a small or no increase in IL-18 production. This finding was not related to a lack of stratum corneum skin penetration since EC50 values (decrease in metabolic activity; MTT assay) were obtained after topical RhE exposure to 8 of the 15 metal salts. For nickel, gold and palladium salts, differences in EC50 values between two salts for the same metal could not be attributed to differences in molarity or valency. For chrome salts the difference in EC50 values may be explained by different valencies (VI vs. III), but not by molarity. In general, metal salts were classified as weaker sensitizers than was indicated from in vivo LLNA EC3 and NOEL data. Our in vitro results show that metals are problematic chemicals to test, in line with the limited number of standardized human and animal studies, which are not currently considered adequate to predict systemic hypersensitivity or autoimmunity, and despite clinical experience, which clearly shows that many metals are indeed a risk to human health.
Topics: Allergens; Animal Testing Alternatives; Epidermis; Haptens; Humans; Infant, Newborn; Interleukin-18; Local Lymph Node Assay; Male; Metals; No-Observed-Adverse-Effect Level; Toxicity Tests
PubMed: 29079364
DOI: 10.1016/j.tox.2017.10.014 -
Sisli Etfal Hastanesi Tip Bulteni 2020Sensitization of allergens varies among societies and also it is influenced by various factors, such as age and gender. It may even change over the years. In this study,...
OBJECTIVES
Sensitization of allergens varies among societies and also it is influenced by various factors, such as age and gender. It may even change over the years. In this study, we aimed to evaluate the patch test results in patients with contact dermatitis (CD) in our center.
METHODS
European standard series patch test results of patients with CD between 2017 and 2018 were evaluated retrospectively.
RESULTS
Of the 135 patients, 65 (48.1%) were males, 70 (51.9%) were females. The mean age of patients was 41.43±14.26 (11-78) years. In 78 (57.8%) patients, a positive reaction against at least one allergen was detected. The most common allergens were nickel sulfate (27.4%), potassium dichromate (14.8%), cobalt chloride (11.9%), textile dye mix (8.1%), fragrance mix i, ii (6.7%) and balsam of Peru (4.4%). The sensitization of nickel sulfate was higher in females and sensitization of cobalt chloride and potassium dichromate in males (p=0.03, 0.05, 0.03, respectively). In the multivariate logistic regression analysis, age was independently related to a positive reaction against at least one allergen.
CONCLUSION
Nickel sulfate, potassium dichromate, cobalt chloride and textile dye mix were the most common allergens. Legal regulations should be made to decrease exposure to allergens.
PubMed: 32617060
DOI: 10.14744/SEMB.2020.02703