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Controlled burning of lead-acid battery plates can release lead-bearing particulate matter that disperses through the air, deposits on passive surfaces, and is transferred to edible crops. This study quantified the source-to-receptor pathway under field-calibrated conditions in Kushtia, Bangladesh, by monitoring PM_2.5 and PM₁₀ across a triangular sampling grid extending to 45 m, assessing passive Pb deposition on Whatman filter papers, and measuring Pb accumulation in red amaranth (Amaranthus tricolor L.). Three battery plates were burned per event, producing an approximate total mass loss of 149.7 ± 4.5 g. PM, deposition, and crop data all exhibited strong distance-dependent gradients, and two-way ANOVA represented significant effects of distance, time/week, and their interaction for all response variables (all p < 0.0001). PM_2.5 showed the strongest distance-dependent association with both filter-paper Pb deposition and Pb accumulation in red amaranth within the sampled range, while PM₁₀ showed significant but weaker associations within the sampled distance range. The background control plot remained below the instrumental detection limit, supporting atmospheric deposition as the dominant exposure pathway. The crop-response model showed an excellent fit (R² = 0.948), since the Codex leafy-vegetable Pb benchmark is based on fresh weight while plant data were measured on a dry-weight basis, the threshold distance was evaluated across a plausible moisture range. Therefore, the 50 m setback is presented as a precautionary recommendation rather than a strict model-derived boundary. The findings provide a mechanistic basis for setback planning around informal battery-burning activities and highlight the food-safety risks of atmospheric Pb transfer to edible crops.

Rice bakanae, a devastating seed-borne disease caused by Fusarium species requires a more attractive and eco-friendly management strategy. The optimization of plant-mediated silver nanoparticles (AgNPs) as nanofungicides by targeting Fusarium species may be a rational approach. In this study, Azadirachta indica leaf aqueous extract-based AgNPs (AiLAE-AgNPs) were synthesized through the optimization of three reaction parameters: A. indica leaf amount, plant extract-to-AgNO₃ ratio (reactant ratio), and incubation time. The optimized green AgNPs were characterized using ultraviolet–visible light (UV–Vis) spectroscopy, field emission scanning electron microscopy (FESEM) with energy dispersive X-ray (EDX) spectroscopy, transmission electron microscopy (TEM), dynamic light scattering (DLS), and powder X-ray diffraction (XRD) techniques. The optimal conditions for producing spherical, unique, and diminutive-sized AgNPs ranging from 4 to 27 nm, with an average size of 15 nm, were 2 g AiLAE at a 1:19 ratio (extract-to-AgNO₃) and incubated for 4 h. Fusarium isolates collected from infected soils and identified as F. fujikuroi (40) and F. proliferatum (58 and 65) by PCR were used for seed infestation. The AgNPs exhibited concentration-dependent mycelial growth inhibition with EC₅₀ values ranging from 2.95 to 5.50 μg/mL. The AgNPs displayed exposure time-dependent seed disinfectant potential (complete CFU reduction in F. fujikuroi (40) and F. proliferatum (58) was observed at a concentration of 17.24 μg/mL). The optimized green AgNPs were non-toxic to germinating seeds, and completely cured bakanae under net-house conditions, suggesting their great nano-fungicidal potency for food security and sustainable agriculture.

Antimicrobials have been used to improve animal welfare, food security, and food safety that promote the emergence, selection, and dissemination of antimicrobial-resistant (AMR) bacteria. In this study, 50 E. coli were isolated from frozen chicken meat samples in Dhaka city. Antibiotic sensitivity patterns were assessed through the disk diffusion method and finally screened for the presence of antimicrobial resistance genes (ARG) using the polymerase chain reaction (PCR). Among the 160 samples, the prevalence of E. coli was observed in fifty samples (31.25%). All of these isolates were found resistant to at least one antimicrobial agent, and 52.0% of the isolates were resistant against 4–7 different antimicrobials. High resistance was shown to tetracycline (66.0%), followed by resistance to erythromycin (42.0%), ampicillin and streptomycin (38.0%), and sulfonamide (28.0%). In addition, the most prevalent ARGs were tet(A) (66.0%), ereA (64.0%), tet(B) (60.0%), aadA1 and sulI (56.0%), blaCITM (48.0%) and blaSHV (40.0%). About 90.0% of isolates were multidrug resistant. This study reveals for the first time the current situation of E. coli AMR in broilers, which is helpful for the clinical control of disease as well as for the development of policies and guidelines to reduce AMR in broilers production in Bangladesh.

Identification of meat and meat products is significant for economic, religious, or public health reasons. This study focused on the detection and differentiation of meat animal species. A total of sixty-four meat samples (10 samples of each like beef, buffen, chevon, and mutton; twenty-four samples of pork) were analyzed for these purposes. PCR-RFLP of 12S rRNA gene with four restriction enzymes was performed on individual meat samples as well as mixture of different meat. Species specific primers as well as sequencing of DNA were also used to detect and verify the RFLP results. PCR amplification yielded a 456bp fragments from 100% samples. AluI digested beef DNA into 359 and 97bp, chevon and mutton DNA into 246 and 210bp fragments and pork DNA into 290 and 166bp fragments. However, it cannot digest buffen DNA. On the other hand HhaI digested only buffen DNA into 247 and 209bp fragments but not others. ApoI restricts only mutton DNA and yielded 329 and 127bp fragments but not others. Nevertheless, BspTI yielded 323 and 133bp fragments only from chevon. Besides, mixed samples (1:1) of beef-buffen and chevon-mutton can be differentiated by AluI & HhaI and BspTI & ApoI, respectively. Chord analysis based on our sequence and respective sequences of studied animals from GenBank indicated that the cutting sites are conserved in these species of animals. Phylogenetically each of the species was clustered separately. This technique may be useful for meat animal species detection and differentiation either from individual meat and mixed meat samples.

Titanium dioxide (TiO2) nanoparticles have a high surface-to-mass ratio and rapidly aggregate in water causing great difficulties for toxicity test exposed to aquatic organisms or other cell lines. This study uses a cell viability kit for routine toxicity test of TiO2 as well as other nanoparticles which accumulate in the aquatic environment. Tetrahymena immediately endocytoses TiO2 nanoparticles and stores them in food vacuoles until the particles undergo exocytosis as larger aggregates. However, during the process of endocytosis and exocytosis, TiO2 particles interfere with cell growth and consequently induce acute toxicity. It exerted high cell growth inhibition at 20 h incubation and induces significant cytotoxic effects. Surprisingly, the effect of TiO2 decreases at 40 h incubation, due to the recovery of cell growth and reduction of the cytotoxicity of the particles.

Antibiotic resistance has become a major clinical and public health problem within
the lifetime of the peoples. The current worldwide increase in resistant bacteria and
simultaneously, the downward trend in the development of new antibiotics have serious
implications. This study isolated and characterized different antibiotic resistance bacteria
present in the hospital effluents of Kushtia district in Bangladesh using selective growth
medium in presence of amoxicillin, tetracycline and penicillin at different concentration.
Salmonella spp, Escherichia coli and Shigella were found to be resistant to these antibiotics. It
also finds that amoxicillin is more resistant to the microorganisms as compared to other two
antibiotics. This study also showed that the gram-negative acquired resistant to antibiotics
rather than gram-positive bacteria in the hospital effluents. Therefore a high level of antibiotic
resistance bacteria is present in the hospital effluents which can be a big health hazard to the
human beings

The study has demonstrated that anticancer drug 5-fluorouracil causes acute toxicity and interferes with the growth of green microalgae, Scenedesmus vacuolatus. It accumulates in microalgae biomass with bioaccumulation factor of 1.84 × 10⁴ and further integrates into the DNA and RNA of microalgae. In addition, the labelled microalgae genome is transferred into protozoan Tetrahymena pyriformis on feeding and is retained in the food vacuoles of predator organisms. This biotransfer of labelled 5-fluorouracil via genomic material was evaluated using radioactivity in Tetrahymena cell pellets though radioactivity did not detect anticancer drug in the genome of the predator organism.

This review summarizes the application of Tetrahymena spp. in ecotoxicology, in order to promote a more integrated, multi-level
ecotoxicological assessment approach regarding the effects of chemical stressors on several biological levels (from molecule to ecosys-
tem). Such a multi-level testing approach in one species facilitates the establishment of missing causal relationships between biochemical
responses and ecological effects. The review illustrates that Tetrahymena spp. represent excellent ecotoxicological test species due to their
important role in the microbial foodweb, wide distribution and abundance, sequenced genome in T. thermophila, large background know-
ledge and scientific publications in cellular biology, ecology and ecotoxicology. Several bioassays have already been developed on differ-
ent biological organisation levels, such as enzyme assays (biochemical level), behavioral tests (individual level), population growth tests
(population level) and microcosms (community level). Moreover, specific mode-of-action based assays are available (e.g. genotoxicity), or
are in development (e.g. endocrine disruption and neurotoxicity). Tetrahymena spp. combine traits of (1) a single cell, thus might replace
or complement specific cell-line testing approaches, with traits of (2) a whole organism and population, thus allowing to study complete
metabolic pathways and its consequences on population growth and genetic adaptation. Assays involving Tetrahymena spp. might easily be
adapted for a rapid multi-level in situ or ex situ toxicity biosensor test system for ecologically relevant risk assessment

Background, aim, and scope

As possible precursors of PFOA, fluorotelomer alcohols are a class of highly fluorinated and volatile compounds. Although they are widespread in the environment, little toxicity data is available. The present study focused on testing the population growth impairment potential of FTOH. Moreover, certain efforts were made to find the possible effect mechanism of these compounds.

Materials and methods

The growth inhibition test was made both in an open system (96-well microplates) and in a closed system (closed flasks). In addition, cells were stained with acridine orange and observed under fluorescence microscopy at 488 nm. Furthermore, direct membrane damage was checked by measuring LDH leakage.

Results

For 8:2 FTOH and 10:2 FTOH, no growth inhibition was found in either of the systems. In contrast, 4:2 FTOH interfered with population growth in the closed system (EC₅₀ = 276.1 mg/L), whereas, 6:2 FTOH had an influence on population growth both in the closed system (EC₅₀ = 64.3 mg/L) and in the open system. Macronucleus destruction was observed with 6:2 FTOH. No direct membrane damage was detectable.

Discussion

With a closed system, 4:2 and 6:2 FTOH were found to be capable of impairing population growth. However, this potential was to a certain extent underestimated. With the help of the air–water distribution coefficient, the real EC₅₀ was estimated within the interval [203.2, 276.1] mg/L and [14.7, 64.3] mg/L for 4:2 and 6:2 FTOH, respectively. Some evidence, such as the absence of direct membrane or macronucleus damage, indicate that certain FTOH could likely cause apoptosis. But the exact effect mechanism could not be determined on the basis of the present results.

A 96-well plate culture methodology for the unicellular eukaryote Tetrahymena pyriformis, strain GL was used for the determination of toxicity and metabolism of catecholamines. Catecholamines exhibited moderate acute toxicity to Tetrahymena cells where dopamine and L-DOPA showed higher toxic potential at EC(10) (0.39 ppm and 0.63 ppm, respectively) and EC(20) (1.1 ppm and 1.0 ppm respectively) after 48 h exposure. All tested catecholamines were highly degradable in the PPY-medium due to the oxidizing environment during incubation. Also the catecholamines were naturally synthesized and released by Tetrahymena cells into the culture medium and increasingly accumulated with time where noradrenalin exhibited the highest degree of accumulation. However, the exogenous exposure of catecholamines to the cells caused the depletion of natural noradrenalin synthesis even with the addition of very low physiological concentration (0.12 ppm). Dopamine caused the higher effect on inhibiting noradrenalin synthesis. Treatment with a higher concentration (8.0 ppm) of dopamine in 96-well plates caused strong excitation of the cells and ascertained a new metabolite in vivo while the other representative catecholamines were not responsible for the production of this metabolite. This dopamine metabolite is relatively non-polar as compared to noradrenalin, adrenaline and dopamine and eluting later through the reverse phase C-18 column.

Adolescence (to grow into adulthood “between ages 10–19 years”) is the most important periods of human life. It is a transitional stage of physical and psychological human development that generally occurs during the period from puberty to legal adulthood. Adolescence is a time of moving from the immaturity of childhood into the maturity of adulthood as composed of a set of transitions such as biological, cognitive, social, and emotional that reveal gradually and that touch upon many aspects of the individual’s behavior, development, and relationships. Empowerment is the expansion of freedom of choice and action. It means increasing one’s authority and control over the resources and decisions that affect one’s life. Social inclusion, autonomy, visibility, mobility, agency, and self-efficacy are the vital concepts associated with the concept of empowerment. In...

The present study was designed to compare the chemical and phytochemical compositions of Momordica charantia, Azadira chtaindica, Trigonella foenum-graecum and Phyllanthus emblica and subsequently, antidiabetic activities of T. foenum-graecum and a combination of polyherbal extract of T. foenum-graecum and M. charantia were evaluated on alloxan induced diabetic mice. The proximate and phytochemical compositions of the plants were quantitatively determined using standard methods. In order to evaluate antidiabetic activity, normal and alloxan induced diabetic mice were orally administered 0.5 mL aqueous extract of T. foenum-graecumand combination of T. foenum-graecum – M. charantia once per day for 7 days. These two plants were selected for antidiabetic activity based on their high phytochemical contents. A near normal blood glucose value of 98.5 ± 0.2 mg / 100mL and 97.02 ± 0.55 mg / 100 mL was observed in the 7^th and 5^th day experimental animals after administration of T. foenum-graecum and T. foenum-graecum – M. charantia, respectively and remained at the same level even after further oral administration. Consequently, it is evident that compared with single extract of T. foenum-graecum, the combined polyherbal extract of T. foenum-graecum – M. charantia promptly lowered blood glucose and maintained a relatively steady level over the study period. However, there was no change in blood glucose levels of control animals subsequent to administration of either extracts of T. foenum-graecum or T. foenum-graecum – M. charantia