Daily dietary intakes of zinc,copper, lead,and cadmium as determined by duplicate portion sampling combined with either instrumental analysis or the use of food composition tables,Shiraz, Iran

Estimation of essential and toxic element intakes is crucial to evaluate the risks of deficiency or toxicity. The purpose of this study was to investigate and also to compare the dietary intakes of zinc (Zn) and copper (Cu) by adults living in Shiraz, Iran, determined by two procedures: duplicate portion sampling of 21 hospital meals combined with either instrumental analysis (voltammetric measurement) or the use of food composition tables (FCTs). The level of exposure to lead (Pb) and cadmium (Cd) was evaluated as well. The daily Zn intakes of both methods were not significantly different and were higher than the RDA values except the value measured by the instrumental analysis which was lower than the RDA established for a male adult. Daily intake of Cu determined by instrumental analysis was significantly lower and closer to RDA for adults compared with the value estimated by FCTs. The dietary intakes of Pb and Cd were 313 and 61 % of the respective provisional tolerable weekly intakes (PTWIs), respectively. The accuracy of two methods used for estimation of Zn intake was similar. In the case of Cu, the use of FCTs, in which the influence of environmental conditions and dietary habits of meal preparation is not taken into account, overestimated dietary intake. The risk of zinc deficiency was found in adult males. Moreover, the estimated intake of Pb, but not Cd, could be a cause of concern for Shiraz population. Thus, conducting regular periodic studies to assess the dietary intake of mentioned elements are recommended.     

Salinity modulates biochemical and histopathological changes caused by silver nanoparticles in juvenile Persian sturgeon (Acipenser persicus)

Environmental Science and Pollution Research - The objective of this study was to evaluate the effect of salinity on the acute and sub-chronic toxicity of silver nanoparticles (AgNPs) in Persian...     

Risk assessment for hazardous lubricants in machining industry

Knowing that over two-thirds of lubricant disposals return to the environment with no purification process, adequate strategies are demanded to reduce their risks. For this reason, the main focus of the present study is to describe an environment-friendly approach. In the first part, two widely used lubricants (mineral-based and vegetable-based) were introduced, and the reasons for their hazards were investigated. The composition of mineral-based lubricant was characterized by x-ray fluorescence elemental analysis. The result showed the presence of phosphorus, chlorine, and zinc dialkyl dithiophosphate in its composition that many scholars considered them to be the leading risk factor in the chemical composition of mineral-based lubricants. It has been focused on the potential risks of vegetable-based lubricants, which many researchers have identified as a safe lubricant. The Pseudomonas microbe was cultivated in the vegetable-based sample, and the result showed that although vegetable-based lubricants are compatible with humans, bacteria colony can quickly grow there without making any apparent changes that lead to harm to operators in a mysterious way. In the present work, the hypothesis of the safety of unreinforced vegetable-based lubricants has been rejected, and a new window on the environmental issues of vegetable-based lubricants has been presented. In the final, to eliminate environment-human risks and to reduce consumption of lubricant and natural resources to green manufacturing, a comprehensive study on the possibility of completely removing lubricant was performed. The results showed that the machining without lubricant could be replaced with the traditional method.

     

Nanoparticles Addition in Coir‐Basalt‐Innegra Fibers Reinforced Bio-synthetic Epoxy Composites

Journal of Polymers and the Environment - In the present investigation, the influence of coir micro-particles and titanium carbide (TiC) nanofillers on mechanical characteristics and thermal...     

Predominance of clade D <Emphasis Type="Italic">Symbiodinium</Emphasis> in shallow-water reef-building corals off Kish and Larak Islands (Persian Gulf,Iran)

Scleractinian coral species harbour communities of photosynthetic taxa of the genus Symbiodinium. As many as eight genetic clades (A, B, C, D, E, F, G and H) of Symbiodinium have been discovered using molecular biology. These clades may differ from each other in their physiology, and thus influence the ecological distribution and resilience of their host corals to environmental stresses. Corals of the Persian Gulf are normally subject to extreme environmental conditions including high salinity and seasonal variation in temperature. This study is the first to use molecular techniques to identify the Symbiodinium of the Iranian coral reefs to the level of phylogenetic clades. Samples of eight coral species were collected at two different depths from the eastern part of Kish Island in the northern Persian Gulf, and Larak Island in the Strait of Hormuz. Partial 28S nuclear ribosomal (nr) DNA of Symbiodinium (D1/D2 domains) were amplified by polymerase chain reaction (PCR). PCR products were analyzed using single stranded conformational polymorphism and phylogenetic analyses of the LSU DNA sequences from a subset of the samples. The results showed that Symbiodinium populations were generally uniform among and within the populations of eight coral species studied, and there are at least two clades of Symbiodinium from Kish and Larak islands. Clade D was detected from eight of the coral species while clade C was found in two of species only (one species hosted two clades simultaneously). The dominance of clade D might be explained by high temperatures or the extreme temperature variation, typical of the Persian Gulf. Publication of this article was held up owing to technical problems. The publisher apologizes sincerely for this lengthy delay.     

Use of chemical coagulants to control fouling potential for wastewater membrane bioreactor processes.

Chemical coagulation with ferric chloride, alum, and an organic polymer were used to control the fouling potential of mixed liquors for submerged membrane bioreactor (MBR) processes in treating municipal wastewater. Their filterability was evaluated using a submerged hollow fiber ultrafiltration apparatus operated in constant permeate flux mode. The collected transmembrane pressures over filtration time were used to calculate the membrane fouling rates. The results showed that coagulation pretreatment can reduce fouling rates when MBRs were operated above the critical flux. Even though coagulation with the organic polymer formed larger mixed liquor suspended solids particles and had shorter time-to-filtration than those with ferric chloride and alum, the filterability for membrane filtration were similar, indicating that the membrane fouling in MBR systems was mainly controlled by the concentration of smaller colloidal particles.