Various Routes Of Exposure Research Articles

Insight into Olfactory Learning, Memory, and Mortality of Apis mellifera jemenitica after Exposure to Acetamiprid Insecticide.

The honey bee, a significant crop pollinator, encounters pesticides through various routes of exposure during foraging and flower visitation. Considering the potential threat of pesticide poisoning, the indigenous Saudi bee Apis mellifera jemenitica is susceptible to the risks associated with acetamiprid, a neonicotinoid insecticide. This study investigates the acetamiprid-induced effects on the survival, olfactory learning, and memory formation of A. m. jemenitica through two exposure routes: topical application and oral ingestion. Field-realistic and serially diluted concentrations (100, 50, 25, and 10 ppm) of acetamiprid led to notable mortality at 4, 12, 24, and 48 h after treatment, with peak mortality observed at 24 h and 48 h for both exposure routes. Bee mortality was concentration-dependent, increasing with the rising concentration of acetamiprid at the tested time intervals. Food consumption following oral exposure exhibited a concentration-dependent pattern, steadily decreasing with increasing concentrations of acetamiprid. Oral exposure resulted in a substantially higher cumulative mortality (55%) compared to topical exposure (15%), indicating a significant disparity in bee mortality between the two exposure routes. The 24 h post-treatment LC50 values for acetamiprid were 160.33 and 12.76 ppm for topical application and oral ingestion, respectively. The sublethal concentrations (LC10, LC20, and LC30) of acetamiprid were 15.23, 34.18, and 61.20 ppm, respectively, following topical exposure, and 2.85, 4.77, and 6.91 ppm, respectively, following oral exposure. The sublethal concentrations of acetamiprid significantly decreased learning during the 2nd-3rd conditioning trials and impaired memory formation at 2, 12, and 24 h following both topical and oral exposure routes, compared to the control bees. Notably, the sublethal concentrations were equally effective in impairing bee learning and memory. Taken together, acetamiprid exposure adversely affected bee survival, hindered learning, and impaired the memory retention of learned tasks.

Human health risks of trace metals through the dietary intake of potato tubers and exposures of potato cultivating soils: A case study of Mymensingh district, Bangladesh

BackgroundTrace metal contamination in soil and farm products is common in Bangladesh, which enhances public awareness. Most of the studies in our country ignored potential human health risks from different routes of exposures to trace metals present in potato tubers and potato-growing soils. ObjectivesThe study objectives were to measure trace metals pollution level in soils, and to evaluate human health risks due to dietary intake of potato tubers, as well as ingestion, dermal and inhalation exposures of potato-cultivating soils of Mymensingh district, Bangladesh. MethodsAn atomic absorption spectrophotometer was used to determine Cd, Ni, Pb, Cr, Cu, Zn, Fe, Co, and Mn in the extract of soils and potato tubers. The study employed contamination factor (CF), pollution load index (PLI), and potential ecological risk index (PERI) to evaluate the level of soil pollution. Non-carcinogenic and carcinogenic human health risks were assessed based on calculated Hazard Quotient and Cumulative Incremental Lifetime Cancer Risk (∑ILCR), respectively. ResultsA threshold of "moderate contamination" (1.0 ≤ CF < 3.0) can be assigned to certain soil sampling sites based on the computed CF values for Ni, Cd, and Pb. On the contrary, the calculated PERI indicated that the soils of potato-cultivating regions of the study area are ecologically free from pollution. Regarding non-cancer risks, the measured hazard quotient (HQ) values for all avenues of exposure to trace metals were below 1.0, indicating that they are safe for human health. On the other hand, the calculated incremental lifetime cancer risk (ILCR) values for Ni in 83.3% of potato tuber samples for both sexes and Cd in 58.3% of males and 91.7% of females had scores greater than 1.00E-04, which indicates carcinogenic risks to adult humans. However, the estimated mean ∑ILCR for males and females in various routes of exposure showed a decreasing trend in the order of ILCROral (potato ingestion) >ILCRSoil ingestion >ILCRDermal adsorption >ILCRSoil inhalation. ConclusionThe agricultural soils of Bangladesh are becoming progressively degraded due to multiple contamination causes along with trace metals. The investigation recommended that future traceability efforts focus on locating possible sites of entry for toxic metals into the nation's food supply chain.

Exposure to heavy metals and neurocognitive function in adults: a systematic review

AbstractExposure of individuals to heavy metals (HMs) is a growing concern with far-reaching implications for human health. HMs encompass a diverse range of elements that, when present in excess or in particular chemical forms, have the potential to elicit adverse effects on the central nervous system and cognitive function. This systematic review aims to comprehensively investigate the relationship between exposure to HMs and neurocognitive function in adults. The methodological framework for this review adheres rigorously to the Meta-analyses Of Observational Studies in Epidemiology (MOOSE) guidelines. A meticulous and extensive search strategy was executed within PubMed and Web of Science, specifically targeting articles published in the English language until the cutoff date of December 5, 2023. The evaluation of the retrieved studies was systematically conducted by employing the assessment approach outlined by (Gascon et al. in Environ Int 86 60 67, 2016). The initial search yielded a substantial pool of 1573 articles, culminating in a refined selection comprising eight pertinent studies, collectively enrolling a participant cohort totalling n = 1,828,126. Notably, the studies under review predominantly manifested a cross-sectional or cohort design and were geographically situated within the continents of North America and Asia. Furthermore, it is imperative to underscore that a predominant and recurring observation emanating from the majority of the scrutinized investigations underscores a significant correlation between exposure to cadmium (Cd) and mercury (Hg) and deleterious neurocognitive outcomes in the adult population. In summary, our systematic review postulates that exposure to HMs through various routes of exposure harbors the potential for adverse effects on adult neurocognitive function; however, it is incumbent upon future research endeavors to validate and corroborate these findings through further empirical exploration.

A Comparative Analysis of RNAi Trigger Uptake and Distribution in Mosquito Vectors of Disease.

In mosquitoes, the utilization of RNAi for functional genetics is widespread, usually mediated through introduced double-stranded RNAs (dsRNAs) with sequence identity to a gene of interest. However, RNAi in mosquitoes is often hampered by inconsistencies in target gene knockdown between experimental setups. While the core RNAi pathway is known to function in most mosquito strains, the uptake and biodistribution of dsRNAs across different mosquito species and life stages have yet to be extensively explored as a source of variation in RNAi experiments. To better understand mosquito-RNAi dynamics, the biodistribution of a dsRNA to a heterologous gene, LacZ (iLacZ), was tracked following various routes of exposure in the larval and adult stages of Aedes aegypti, Anopheles gambiae, and Culex pipiens. iLacZ was largely limited to the gut lumen when exposed per os, or to the cuticle when topically applied, but spread through the hemocoel when injected. Uptake of dsRNA was noted in a subset of cells including: hemocytes, pericardial cells of the dorsal vessel, ovarian follicles, and ganglia of the ventral nerve cord. These cell types are all known to undergo phagocytosis, pinocytosis, or both, and as such may actively take up RNAi triggers. In Ae. aegypti, iLacZ was detected for up to one week post exposure by Northern blotting, but uptake and degradation drastically differed across tissues. The results presented here reveal that the uptake of RNAi triggers is distinct and specific to the cell type in vivo.

Регламентування у повітряному середовищі біоцидного препарату «LONZABAC GA» за маркерною леткою сполукою

Lonzabac GA (active ingredient – cocopropylenediamineguanidine acetate) is used as basic component in manufacturing surface and medical instrument disinfectants. In Ukraine, disinfectants are subject to sanitary standardization and obtaining of marketing authorization. Given that the active ingredient Lonzabac GA is non-volatile, the question came up of detecting volatile compounds that can get into the air during its use, with subsequent establishment of a marker compound to be used to monitor the air quality. The objective of this paper was to study the toxicity of LONZABAC GA at laboratory animals with various routes of exposure as part of sanitary standardization and to justify the drug administration standard based on marker volatile compound. To this end the sanitary and chemical, toxicological, and statistical research methods were used. Results: Lonzabac GA classifies as hazard class 3 in terms of acute oral toxicity. It has no skin resorptive effect. Lonzabac GA has dermal and mucous membranes irritating action. Significant cumulative activity. It cause no body sensitization. Lonzabac GA, when used as disinfectant component, does not form drug aerosol, instead, an isopropyl alcohol migrates from the drug into the air. No LС50 was reached in acute ingestion experiment. The experimental animals showed no clinical signs of intoxication, changes in biochemical and hematological parameters during chronic inhalation study. Conclusions: Therefore, it is advisable to monitor air quality both during manufacture and use of Lonzabac GA based on concentration of marker compound – isopropyl alcohol.

Comparative proteomic analysis reveals the different hepatotoxic mechanisms of human hepatocytes exposed to silver nanoparticles

Silver nanoparticles (AgNPs), which have been used extensively in consuming products and eventually released into the natural environment, have aroused concerns recently because of their potentially harmful effects on human beings following various routes of exposure. As the liver is one of the largest accumulation and deposition sites of circulatory AgNPs, it is important to evaluate the hepatotoxicity induced by AgNPs. However, the acting mechanisms of AgNPs-induced hepatotoxicity are still elusive to a great extent. Herein, we investigated the hepatotoxic effects of AgNPs using a comparative proteomics approach. First, we evaluated the cytotoxicity of different-sized AgNPs and found that the cancerous liver cells were generally more sensitive than the normal liver cells. Next, proteomics results suggested that HepG2 and L02 cells showed distinct adaptive responses upon AgNPs exposure. HepG2 cells respond to stresses by adapting energy metabolism, upregulating metallothionein expression and increasing the expression of antioxidants, while L02 cells protect themselves by increasing DNA repair and macro-autophagy. Besides, mitochondrial ROS has been identified as one of the causes of AgNPs-induced hepatotoxicity. Collectively, our results revealed that hepatic cancer cells and normal cells cope with AgNPs in notably different pathways, providing new insights into mechanisms underlying AgNPs-induced hepatotoxicity. Data availabilityThe mass spectrometry proteomics data have been deposited to the ProteomeXchange Consortium (Deutsch et al. (2020)) via the PRIDE (Perez-Riverol et al. (2019)) partner repository with the dataset identifier PXD029511.

Acute lung and lower respiratory tract damage after inhalation exposure to hydrogen fluoride

Relevance. Hydrogen fluoride is a highly active chemical substance widely used in industry for production of inorganic fluorides, organofluorine compounds, in the processing of aluminum, stainless steel and alloys. The chemical properties of hydrogen fluoride determine its ability to have a destructive effect on the tissues of the human body and high toxicity with local and systemic exposure. Hydrogen fluoride poisoning is severe and difficult to treat. Clarification of the clinical picture and the search for new methods of treating lesions with hydrogen fluoride are of great importance for protecting the health of workers in chemical industries and eliminating the consequences of technogenic accidents.Intention. To consider the features of the observed clinical case of severe damage to the lungs and lower respiratory tract after inhalation exposure to hydrogen fluoride and treatment methods that made it possible to achieve favorable clinical results. Methodology. The article discusses clinically important chemical properties of hydrogen fluoride, the mechanisms and manifestations of characteristic lesions developing in the human body with various routes of exposure. Modern approaches to the treatment of patients exposed to hydrogen fluoride are outlined.Results and Discussion. Inhalation of gas mixtures, even with low concentrations of hydrogen fluoride, can lead to severe inflammatory-necrotic lung damage with interstitial pneumonia (chemical pneumonitis), adult respiratory distress syndrome, and severe respiratory failure. Improvement of clinical condition of the affected person in the observed case was achieved via complex treatment with glucocorticosteroids, antimicrobial agents, calcium gluconate inhalations. A key role in the patient’s treatment was played by long-term replacement of the impaired function of the lungs using extracorporeal membrane oxygenation.Conclusion. In severe forms of acute damage to the lungs and lower respiratory tract as a result of inhaled exposure to hydrogen fluoride, clinical recovery and improvement in the quality of life of the injured can be achieved through complex therapy using glucocorticosteroids, antibacterial agents, specific antidotes (calcium gluconate) and prolonged replacement of the respiratory function via artificial ventilation and extracorporeal membrane oxygenation.

Association between urinary concentration of phthalate metabolites and allergic disorders in Korean children: Korean National Environmental Health Survey (KoNEHS) 2015-2017

BACKGROUND AND AIM: Phthalates are common industrial chemicals used primarily as plasticizers that make plastic flexible. Children are more prone to these chemicals through various routes of exposure including dermal absorption, inhalation, and ingestion (such as food, water, and dust) than adults and several studies have reported that phthalate exposure may increase the risk of allergic diseases. Therefore, we aimed to examine the association between urinary concentration of phthalate metabolites and allergic disorders in a nationally representative sample of Korean children. METHODS: In this study, we used data on urinary phthalate metabolites, allergic symptoms such as atopic dermatitis (AD), asthma, and allergic rhinitis (AR), and serum total immunoglobin E (IgE) levels from participants aged 3–17 in the Korean National Environmental Health Survey 2015–2017. After adjusted for all covariates, Odds ratio (OR) and their 95% confidence intervals (95% CI) per one ln–unit increase change in the concentration of phthalate metabolites were estimated using logistic regression. RESULTS:Urinary high–molecular–weight phthalate metabolites (HMW) were positively associated with current AD and AR. A significant increase of the OR for high group of IgE levels with increase of urinary mono-(carboxynonyl) phthalate (MCNP) concentrations was found [OR=1.43 (1.06, 1.91)]. Mono–benzyl phthalate, mono–(carboxyoctyl) phthalate, and mono–(2–ethyl–5–oxohexyl) phthalate were positively associated with allergic multimorbidity which means co–occurrence of at least two allergic diseases in one individual. Children with high IgE were more likely to have an AR associated MCNP than those with low IgE or high IgE only (p = 0.007). Specifically, we estimated that 14.7% of total effect of MCNP on AR was mediated by IgE. However, no phthalate metabolites were significantly associated with current asthma. CONCLUSIONS:Our observations revealed that some HMW phthalate metabolites were positively associated with current allergic symptoms and high total IgE levels in children. These results suggested that environmental exposure to phthalates could enhance allergic response in children. KEYWORDS: Atopic dermatitis, Asthma, Allergic rhinitis, Allergic multimorbidity, Total immunogliblin E, Phthalate metabolites

A New Challenge for the Management and Disposal of Personal Protective Equipment Waste during the COVID-19 Pandemic

To prevent the transmission of the Coronavirus (SARS-CoV-2) in the public, the demand and consumption of personal protective equipment (PPE) increased drastically. Such wide use of PPE has brough a new challenge to waste management and disposal. It is difficult to sort PPE waste before further treatment, and such waste will often end up being processed by some traditional disposal methods. During the pandemic, incineration and landfill facilities are currently under significant pressure. In addition, a certain amount of PPE waste is discarded into the environment rather than going to landfills and incinerators. It not only directly affects the ecosystem, but also indirectly threatens human health through various routes of exposure. PPE waste is also the source and carrier of pathogens and chemical contaminants, causing a secondary pollution. Therefore, it is necessary to establish appropriate strategies to deal with the PPE problems related to energy, environment and health, requiring the collaborative efforts of researchers, practitioners, policymakers, and governments.

The Experimental Study of Cardiotoxic Effects of Lead Oxide Nanoparticles by Their Various Routes of Exposure

Background: Lead oxide nanoparticles are emitted in the workplace air of copper smelters. They are also a by-product in many other metallurgical industries. Objectives: Adverse health effects of lead oxide nanoparticles (PbO-NPs) were assessed in vivo using various routes of exposure with special attention paid to particle cardiotoxicity. Materials and methods: The subacute inhalation experiments were conducted on outbred female rats exposed to the generated aerosol of PbO-NPs in the concentration of 1.30 ± 0.10 mg/m3, 4 hours a day during five consecutive days, using the Nose-Only Inhalation Exposure System. The study of subchronic exposure to PbO-NPs was conducted on male rats using intraperitoneal injections made thrice a week during six weeks (18 injections in total). Conclusions: Following both types of exposure to PbO-NPs, we observed changes in toxicological indices including those specific for lead including a decrease in hemoglobin counts, an increase in blood reticulocyte counts and urine concentrations of δ-aminolevulenic acid. The subacute inhalation exposure to PbO-NPs affected electrocardiographic findings in animals (an increase in amplitudes of P and T waves) while the subchronic intraperitoneal injections decreased blood pressure and changed biochemical indices of the cardiovascular system (decreased activity of the angiotensin-converting enzyme and the concentration of endodelin-1).

Health Impact of Silver Nanoparticles: A Review of the Biodistribution and Toxicity Following Various Routes of Exposure.

Engineered nanomaterials (ENMs) have gained huge importance in technological advancements over the past few years. Among the various ENMs, silver nanoparticles (AgNPs) have become one of the most explored nanotechnology-derived nanostructures and have been intensively investigated for their unique physicochemical properties. The widespread commercial and biomedical application of nanosilver include its use as a catalyst and an optical receptor in cosmetics, electronics and textile engineering, as a bactericidal agent, and in wound dressings, surgical instruments, and disinfectants. This, in turn, has increased the potential for interactions of AgNPs with terrestrial and aquatic environments, as well as potential exposure and toxicity to human health. In the present review, after giving an overview of ENMs, we discuss the current advances on the physiochemical properties of AgNPs with specific emphasis on biodistribution and both in vitro and in vivo toxicity following various routes of exposure. Most in vitro studies have demonstrated the size-, dose- and coating-dependent cellular uptake of AgNPs. Following NPs exposure, in vivo biodistribution studies have reported Ag accumulation and toxicity to local as well as distant organs. Though there has been an increase in the number of studies in this area, more investigations are required to understand the mechanisms of toxicity following various modes of exposure to AgNPs.

A CYTOLOGICAL STUDY OF IMPRINT SMEARS (TOUCH PREPARATION CYTOLOGY) TO EVALUATE THE TOXICITY OF METAL-CONTAINING NANOPARTICLES IN EXPERIMENTAL ANIMALS

Introduction. Touch preparation cytology is a well-known technique widely used in clinical practice. It can be also applied for an express assessment of cyto-morphological effects of metal-containing nanoparticles in experimental animals. Material and methods. We’ve studied 144 imprint smears (of the liver, kidneys, lungs, tracheobronchial and mesenteric lymph nodes) taken from 52 rats, weighed 280-300 g, aged 3.5 months. This was done following a subchronic intraperitoneal administration of TiO2, Al2O3, and SiO2 nanoparticles, in a range of doses, and a subacute (5-times) inhalational exposure to 1 mg/m3 NiO NPs. Leishman stain was used. Cytological markers were studied at х100/х1000 magnification, using a Carl Zeiss Primo Star microscope, with a USCMOS camera for visualization. The count was done for every 200 cells of lung, liver and kidney specimens and for every 100 cells of lymph node tissue. The differences between the group means (in case of quantitative results) were analyzed using a Student’s t-test. The differences between the group means were considered statistically significant if the probability of those differences being accidental didn’t exceed 5% (р &lt; 0,05). Results. We report the principal results obtained in a cytological study of imprint smears (touch preparations) of rat organs following the exposure to metal-containing nanoparticles. The main types of cellular responses were determined. Degenerative and dystrophic changes were observed in touch preparations of the liver, kidneys, and lungs following administration of nanoparticles in a range of doses and by various routes of exposure. Hyperergic inflammatory responses were seen upon the exposure to nickel oxide nanoparticles. A local cellular immune response was observed as an increase of macrophage percentage in imprint smears of some organs. Conclusion. The use of touch preparation cytology together with histological examination of tissue specimens expand opportunities for a more relevant morphological and quantitative analysis when studying the toxic effects of metal-containing nanoparticles.

ПРИМЕНЕНИЕ ЦИТОЛОГИЧЕСКОГО МЕТОДА ИССЛЕДОВАНИЯ МАЗКОВ У ЭКСПЕРИМЕНТАЛЬНЫХ ЖИВОТНЫХ ДЛЯ ОЦЕНКИ ТОКСИЧЕСКОГО ДЕЙСТВИЯ МЕТАЛЛОСОДЕРЖАЩИХ НАНОЧАСТИЦ

Introduction. Touch preparation cytology is a well-known technique widely used in clinical practice. It can be also applied for an express assessment of cyto-morphological effects of metal-containing nanoparticles in experimental animals. Material and methods. We’ve studied 144 imprint smears (of the liver, kidneys, lungs, tracheobronchial and mesenteric lymph nodes) taken from 52 rats, weighed 280-300 g, aged 3.5 months. This was done following a subchronic intraperitoneal administration of TiO2, Al2O3, and SiO2 nanoparticles, in a range of doses, and a subacute (5-times) inhalational exposure to 1 mg/m 3 NiO NPs. Leishman stain was used. Cytological markers were studied at х100/х1000 magnification, using a Carl Zeiss Primo Star microscope, with a USCMOS camera for visualization. The count was done for every 200 cells of lung, liver and kidney specimens and for every 100 cells of lymph node tissue. The differences between the group means (in case of quantitative results) were analyzed using a Student’s t-test. The differences between the group means were considered statistically significant if the probability of those differences being accidental didn’t exceed 5% (р < 0,05). Results. We report the principal results obtained in a cytological study of imprint smears (touch preparations) of rat organs following the exposure to metal-containing nanoparticles. The main types of cellular responses were determined. Degenerative and dystrophic changes were observed in touch preparations of the liver, kidneys, and lungs following administration of nanoparticles in a range of doses and by various routes of exposure. Hyperergic inflammatory responses were seen upon the exposure to nickel oxide nanoparticles. A local cellular immune response was observed as an increase of macrophage percentage in imprint smears of some organs. Conclusion. The use of touch preparation cytology together with histological examination of tissue specimens expand opportunities for a more relevant morphological and quantitative analysis when studying the toxic effects of metal-containing nanoparticles.

Trophic transfer affects cytogenetic and antioxidant responses of the mussel Mytilus galloprovincialis to copper and benzo(α)pyrene

The impacts of environmental pollutants on marine organisms can be determined by the routes of exposure. Various routes of exposure, including dietary exposure and waterborne exposure with or without feeding, were applied to study the cytogenetic responses in marine mussels Mytilus galloprovincials to typical pollutants, BaP (53.74 ± 19.79 μg/L) and Cu (47.38 ± 3.10 μg/L). The increased DNA strand breaks and micronucleus formation were found in haemocytes of mussels via the dietary exposure, indicating the vital role of trophic transfer in toxicity induction. The deeper exploration to relate BaP induced cytogenetic alterations with key antioxidant defense factors, SOD and GST, was performed under different exposure routes. The results revealed the significantly inhibited SOD activity via the trophic transfer, suggesting more direct or prompt role of SOD in antioxidant defense. On contrary, gene expressions of both sod and gst were up-regulated upon all routes of exposures, and showed negative correlation with enzyme activities. The results suggested the asynchronous regulation of studied antioxidant factors at transcriptional and enzyme functional level in mussels upon the change of exposure routes. The study brings out the first observation of trophic transfer influenced cytogenetic and antioxidant responses to pollutants and their alterative risk to marine organisms.

Assessing Human Exposure to Organic Pollutants in the Indoor Environment.

There is an ongoing probing of the role of chemicals in the indoor environment. The majority of potential target substances are so-called very volatile, volatile, and semi-volatile organic compounds (VVOCs, VOCs, and SVOCs). Depending on their physical properties and the mass transfer conditions, they are distributed in or between the gas phase, particle phase, settled house dust, surface films, clothing, and other fabrics as well as the exposed skin and hair of the occupants themselves. Therefore, inhalation, ingestion, and dermal uptake all must be considered as relevant pathways for exposure assessment in human habitats. Exposure to VVOCs, VOCs, and SVOCs can be estimated by measuring their concentrations in relevant indoor compartments or by determining the amounts of the target compounds and/or their metabolites in urine and blood. Assessing the various routes of exposure often requires a combination of sophisticated and interdisciplinary theoretical background and experimental techniques. Consequently, close communication and collaboration between chemical and exposure scientists are needed to achieve a better understanding of human exposure to chemical substances in various indoor environments. Embedded in the toxicological context, this is the basis for assessing the corresponding health risks and for determining control strategies or approaches to limit such risks.

A review of the potential risks associated with chemicals present in poured-in-place rubber surfacing

Poured-in-place (PIP) rubber surface systems are becoming a popular material for playground and play area surfaces due to their customizability, durability, and impact protection. The material is constructed from crumb rubber, which is made from recycled tires as well as synthetic components and other additives, such as a binding agent. Several government agencies and nongovernmental organizations have commissioned studies and status reports to identify possible health risks related to exposure to the chemical hazards present in PIP surface materials. Various routes of exposure were considered such as inhalation, ingestion, and dermal contact. After a review of the available literature addressing potential chemical hazards of PIP surfaces, no health risks were noted. Some information gaps, such as limited experimental data specific to PIP surface systems, were identified at the time of the review.

Morphological characterisation of lettuce plasma membrane ultrastructure and vesicle formation caused by nonylphenol: A scanning electron microscopy study

Fresh produce can come into contact with nonylphenol (NP), a widely used surfactant and industrial endocrine disrupting chemical, through various routes of exposure in the agricultural environment. Nonylphenol has been linked to immunological and behavioural abnormalities as well as infertility and cancer in mammals. One of its modes of action is believed to be through damaging the plasma membrane of cells. While it has been demonstrated that NP can be phytotoxic, its effect on plant cell membrane integrity has not yet been examined. In this study, the plasma membranes of lettuce protoplasts were analysed with a high- resolution scanning electron microscope (SEM). The protoplasts were isolated from plants that had been exposed to 800, 1600, 3200, 6400 and 12,800μg/l NP, respectively, for three weeks. The plasma membrane of the protoplasts that were exposed to 6400 and 12,800μg/l NP showed vesicle-like protrusions, accompanied by flattening of the membrane in its direct vicinity. This study showed that NP caused changes in the ultrastructure of lettuce plasma membranes, thereby compromising its functionality. To the best of our knowledge, this paper describes for the first time the morphology of the plasma membrane using high-resolution SEM.

Reported Adverse Health Effects in Children from Ingestion of Alcohol-Based Hand Sanitizers - United States, 2011-2014.

Hand sanitizers are effective and inexpensive products that can reduce microorganisms on the skin, but ingestion or improper use can be associated with health risks. Many hand sanitizers contain up to 60%-95% ethanol or isopropyl alcohol by volume, and are often combined with scents that might be appealing to young children. Recent reports have identified serious consequences, including apnea, acidosis, and coma in young children who swallowed alcohol-based (alcohol) hand sanitizer (1-3). Poison control centers collect data on intentional and unintentional exposures to hand sanitizer solutions resulting from various routes of exposure, including ingestion, inhalation, and dermal and ocular exposures. To characterize exposures of children aged ≤12 years to alcohol hand sanitizers, CDC analyzed data reported to the National Poison Data System (NPDS).* The major route of exposure to both alcohol and nonalcohol-based (nonalcohol) hand sanitizers was ingestion. The majority of intentional exposures to alcohol hand sanitizers occurred in children aged 6-12 years. Alcohol hand sanitizer exposures were associated with worse outcomes than were nonalcohol hand sanitizer exposures. Caregivers and health care providers should be aware of the potential dangers associated with hand sanitizer ingestion. Children using alcohol hand sanitizers should be supervised and these products should be kept out of reach from children when not in use.

Toxicity, toxicokinetics and biodistribution of dextran stabilized Iron oxide Nanoparticles for biomedical applications

Advancement in the field of nanoscience and technology has alarmingly raised the call for comprehending the potential health effects caused by deliberate or unintentional exposure to nanoparticles. Iron oxide magnetic nanoparticles have an increasing number of biomedical applications and hence a complete toxicological profile of the nanomaterial is therefore a mandatory requirement prior to its intended usage to ensure safety and to minimize potential health hazards upon its exposure. The present study elucidates the toxicity of in house synthesized Dextran stabilized iron oxide nanoparticles (DINP) in a regulatory perspective through various routes of exposure, its associated molecular, immune, genotoxic, carcinogenic effects and bio distribution profile. Synthesized ferrite nanomaterials were successfully coated with dextran (<25nm) and were physicochemically characterized and subjected to in vitro and in vivo toxicity evaluations. The results suggest that surface coating of ferrite nanoparticles with dextran helps in improvising particle stability in biological environments. The nanoparticles do not seem to induce oxidative stress mediated toxicological effects, nor altered physiological process or behavior changes or visible pathological lesions. Furthermore no anticipated health hazards are likely to be associated with the use of DINP and could be concluded that the synthesized DINP is nontoxic/safe to be used for biomedical applications

Laboratory bioassays on the impact of cadmium, copper and lead on the development and survival of honeybee (Apis mellifera L.) larvae and foragers

Honeybees (Apis mellifera L.) have been widely distributed around the world to serve as pollinators for agriculture. They can encounter metal pollutants through various routes of exposure, including foraging on contaminated plant resources. Chronic and acute toxicity tests were conducted on larvae using artificial diets and on foragers using solutions of 50% sucrose, which contained cadmium (Cd), copper (Cu) and lead (Pb). We found that mortality increased in both larvae and foragers in a dose-dependent manner. Control larvae had higher relative growth indices (RGI) from day 6 to day 10 compared to all metal treatments, demonstrating substantial negative effects of metals on development. Copper was the least toxic to larvae with an LC50 of 6.97 mg L−1. For foragers, Pb had the highest LC50, which was 345 mg L−1. Foragers and larvae accumulated substantial quantities of all metals, and subsequent sucrose consumption decreased after dosing. Overall, honeybee larvae and foragers suffered detrimental effects when they were exposed to ecologically-relevant concentrations of Cd, Cu and Pb.