Investigation of heavy metal contents in Cow milk samples from area of Dhaka, Bangladesh

Background: Cow milk is considered as one of the responsible food sources contaminated with heavy metals. The objectives of the study were to assess the content of selected metals in cow milk and its associated human health risks in the food chain of Bangladesh. A total of 90 cow milk samples of Branded, Dairy and Domestically produced milk were collected randomly from different sources of Savar Upazila in Dhaka area. Cadmium (Cd), chromium (Cr), lead (Pb), manganese (Mn), copper (Cu) and iron (Fe) contents in collected milk samples were determined using Flame Atomic Absorption Spectrometry (FAAS). To ensure quality control, one of the best quality control parameters i.e. recovery test; from eight various sample digestion methods were used. The Hazard Quotient (HQ) and Carcinogenic Risk (CR) values were also calculated. Results: From the results, it was found that, the orders of heavy metal content in brand, dairy and domestic cow milk were Cr > Fe > Cu>Mn > Cd > Pb, Cr > Fe > Mn > Cu > Cd > Pb and Fe > Cr > Mn > Cu > Cd > Pb, respectively. Among the six metals, only Cr showed to exceed the highest Estimated Daily Intake (EDI) rate (for brand cow milk: 0.413 mg/day, dairy farm cow milk: 0.243 mg/day, domestic cow milk: 0. 352 mg/day),and the comparison percentages of calculated values per permeable values were as follows; 206.5 % for brand cow milk,121.5 % for dairy farm cow milk and 176.0 % for domestic cow milk. Hazard Quotients (HQ) values and Carcinogenic Risk (CR) values were found within the acceptable level. Conclusion: Although, the metal content in sampled cow milks were within the safe limit, the potential human health risks cannot be neglected for the regular/long time consumption of heavy metal contained cow milk

Altered Response to Total Body Irradiation of C57BL/6-Tg (CAG-EGFP) Mice

Application of green fluorescent protein (GFP) in a variety of biosystems as a unique bioindicator or biomarker has revolutionized biological research and made groundbreaking achievements, while increasing evidence has shown alterations in biological properties and physiological functions of the cells and animals overexpressing transgenic GFP. In this work, response to total body irradiation (TBI) was comparatively studied in GFP transgenic C57BL/6-Tg (CAG-EGFP) mice and C57BL/6 N wild type mice. It was demonstrated that GFP transgenic mice were more sensitive to radiation-induced bone marrow death, and no adaptive response could be induced. In the nucleated bone marrow cells of GFP transgenic mice exposed to a middle dose, there was a significant increase in both the percentage of cells expressing pro-apoptotic gene Bax and apoptotic cell death. While in wild type cells, lower expression of pro-apoptotic gene Bax and higher expression of anti-apoptotic gene Bcl-2, and significant lower induction of apoptosis were observed compared to GFP transgenic cells. Results suggest that presence of GFP could alter response to TBI at whole body, cellular and molecular levels in mice. These findings indicate that there could be a major influence on the interpretation of the results obtained in GFP transgenic mice

Reduced High-Dose Radiation-Induced Residual Genotoxic Damage by Induction of Radioadaptive Response and Prophylactic Mild Dietary Restriction in Mice

Radioadaptive response (RAR) describes a phenomenon in a variety of in vitro and in vivo systems that a low-dose of priming ionizing radiation (IR) reduces detrimental effects of a subsequent challenge IR at higher doses. Among in vivo investigations, studies using the mouse RAR model (Yonezawa Effect) showed that RAR could significantly extenuate high-dose IR-induced detrimental effects such as decrease of hematopoietic stem cells and progenitor cells, acute radiation hematopoietic syndrome, genotoxicity and genomic instability. Meanwhile, it has been demonstrated that diet intervention has a great impact on health, and dietary restriction shows beneficial effects on numerous diseases in animal models. In this work, by using the mouse RAR model and mild dietary restriction (MDR), we confirmed that combination of RAR and MDR could more efficiently reduce radiogenotoxic damage without significant change of the RAR phenotype. These findings suggested that MDR may share some common pathways with RAR to activate mechanisms consequently resulting in suppression of genotoxicity. As MDR could also increase resistance to chemotherapy and radiotherapy in normal cells, we propose that combination of MDR, RAR, and other cancer treatments (i.e., chemotherapy and radiotherapy) represent a potential strategy to increase the treatment efficacy and prevent IR risk in humans

Citrulline, a potential biomarker of radiation-induced small intestine damage

Radiation damage assessment of the small intestine is important in nuclear accidents or routine radiotherapy of abdominal tumors. This article reviews the clinical symptoms and molecular mechanisms of radiation-induced small intestinal damage and summarizes recent research on biomarkers of such damage. Citrulline is the most promising biomarker for the evaluation of radiation-induced small intestinal damage caused by radiotherapy and nuclear accidents. This article also summarizes the factors influencing plasma citrulline measurement investigated in the latest research, as well as new findings on the concentration of citrulline in saliva and urine after different types of radiation.キーワードBiomarker, small intestine damage, citrulline, radiatio

Toxicity risks associated with heavy metals to fish species in the Transboundary River – Linked Ramsar Conservation Site of Tanguar Haor, Bangladesh

The presence of trace metals in aquatic ecosystems can have detrimental effects on fish survival. The Tanguar haor, a Ramsar conservation wetland, receives sediment and water from multiple transboundary rivers. However, there have been limited studies on the metal concentrations in fish species in this sediment-rich wetland. This study aimed to analyze the concentrations of iron (Fe), manganese (Mn), chromium (Cr), copper (Cu), zinc (Zn), cadmium (Cd), and lead (Pb) in water, sediment, and fish tissues. Higher concentrations of Cd and Pb were found in the water and sediment. All these metals were detected in eight fish species, including benthic and pelagic species. Among them, Systomus sarana, a pelagic fish that also consumes benthic organisms, exhibited a higher metal pollution index than other fish, particularly benthic species. The release of higher metal concentrations from sediment into the water has the potential to impact the accumulation of metals in fish. Synopsis: This study on metal concentrations in fish species will aid policymaking on ecotoxicology research for transboundary river-connected wetlands

Microbial decontamination of gamma irradiated black tea and determination of major minerals in black tea, fresh tea leaves and tea garden soil

The purpose of this research was to establish an effective dose of gamma irradiation to eliminate any possible bacterial contamination as well as assess the levels of essential major elements [sodium (Na), potassium (K), calcium (Ca), magnesium (Mg) and iron (Fe)] present in black tea. The samples were compared to fresh tea leaves and soil from the tea gardens of two distinct tea cultivating regions (Sylhet and Moulvibazar) in Bangladesh. Maximum coliform bacterial contaminants (4.0 × 10 cfu/g) were completely eliminated following an irradiation dose of 2.5 kGy, whereas a viable bacterial load of 9.0 × 10 cfu/g was completely eliminated at 5.0 kGy. Major elements were present at higher concentrations in black tea samples originating from Sylhet compared to those from Moulvibazar. Among the analyzed elements, only Na and Fe were present at higher concentrations in the fresh tea leaves from Sylhet, whereas K, Ca and Mg were observed at higher concentrations in the tea leaves from Moulvibazar. The amount of each mineral in the black tea is acceptable for daily intake and is safe for consumption. It is concluded that black tea from Bangladesh is a rich source of minerals and could be free of microbial contamination after receiving 5.0 kGy of gamma radiation

Altered Response to Total Body Irradiation of C57BL/6-Tg (CAG-EGFP) Mice

Application of green fluorescent protein (GFP) in a variety of biosystems as a unique bioindicator or biomarker has revolutionized biological research and made groundbreaking achievements, while increasing evidence has shown alterations in biological properties and physiological functions of the cells and animals overexpressing transgenic GFP. In this work, response to total body irradiation (TBI) was comparatively studied in GFP transgenic C57BL/6-Tg (CAG-EGFP) mice and C57BL/6 N wild type mice. It was demonstrated that GFP transgenic mice were more sensitive to radiation-induced bone marrow death, and no adaptive response could be induced. In the nucleated bone marrow cells of GFP transgenic mice exposed to a middle dose, there was a significant increase in both the percentage of cells expressing pro-apoptotic gene Bax and apoptotic cell death. While in wild type cells, lower expression of pro-apoptotic gene Bax and higher expression of anti-apoptotic gene Bcl-2, and significant lower induction of apoptosis were observed compared to GFP transgenic cells. Results suggest that presence of GFP could alter response to TBI at whole body, cellular and molecular levels in mice. These findings indicate that there could be a major influence on the interpretation of the results obtained in GFP transgenic mice

Water and bottom sediments quality of brackish water shrimp farms in Kaliganj Upazila, Satkhira, Bangladesh

Shrimp culture plays a central part in the fisheries sector of Bangladesh that leads to a significant change in the structure and composition of frozen food export sector. An investigation was carried out to determine physiochemical parameters, nutrients content, bacterial contamination and metal content in shrimp “Gher” (Farms) water and sediments. Physicochemical parameters were analyzed in situ by portable meters. Ammonia, phosphate, bacterial counts, and metals contents were analyzed by Nesslerization, colorimetric and standard microbiological methods and Atomic Absorption Spectrophotometery (AAS), respectively. Except Dissolve oxygen and temperature all other physiochemical parameters were unsuitable for shrimp culture. The concentration of ammonia was 0.384 to 1.5 mg L-1 and the concentration of phosphate ranged from 0.02 to 0.818 mg L-1. In bacteriological analysis, highest levels of coliform were found in the tested samples and total colifom count reached up to 2.04x103 cfu mL-1. Among the tested metals, Cr was highest in water and sediment samples. Concentration of Cr ranged from 0.150 to 0.807 mg L-1 and 1.957 to 3.436 mg kg-1 in water and sediment samples, respectively. A significant difference was observed for the concentration of metals in sediment and water samples. The high concentration of nutrients and metals in shrimp “Gher” water and sediment as well as the presence of pathogenic bacteria in the “Gher” and river water indicated unhygienic environment and the sources of contamination of shrimp “Gher”

Reduced high-dose radiation-induced residual genotoxic damage by induction of radioadaptive response and prophylactic mild dietary restriction in mice.

Radioadaptive response (RAR) describes a phenomenon in a variety of in vitro and in vivo systems that a low-dose of priming ionizing radiation (IR) reduces detrimental effects of a subsequent challenge IR at higher doses. Among in vivo investigations, studies using the mouse RAR model (Yonezawa Effect) showed that RAR could significantly extenuate high-dose IR-induced detrimental effects such as decrease of hematopoietic stem cells and progenitor cells, acute radiation hematopoietic syndrome, genotoxicity and genomic instability. Meanwhile, it has been demonstrated that diet intervention has a great impact on health, anddietary restriction shows beneficial effects on numerous diseases in animal models. In this work, by using the mouse RAR model and mild dietary restriction (MDR), we confirmed that combination of RAR and MDR could more efficiently reduce radiogenotoxic damage without significant change of the RAR phenotype. These findings suggested that MDR may share some common pathways with RAR to activate mechanisms consequently resulting in suppression of genotoxicity. As MDR could also increase resistance to chemotherapy and radiotherapy in normal cells, we propose that combination of MDR, RAR, and other cancer treatments (i.e., chemotherapy and radiotherapy) represent a potential strategy to increase the treatment efficacy and prevent IR risk in humans