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Fluoride contents in tea and soil from tea plantations and the release of fluoride into tea liquor during infusion
1999
Fung, K.F. | Zhang, Z.Q. | Wong, J.W.C. | Wong, M.H. (Institute for Natural Resources and Waste Management, and Department of Biology, Hong Kong Baptist University, Kowloon Tong, Hong Kong (China))
Study of controlled migration of cadmium and lead into foods from plastic utensils for children
2022
Pereira, Elizeu Chiodi | Leroux, Isabelle Nogueira | Luz, Maciel Santos | Batista, Bruno Lemos | Olympio, Kelly Polido Kaneshiro
Lead (Pb) is a highly neurotoxic chemical element known for reducing intelligence quotient (IQ) and promoting antisocial behavior in children and adolescents, while cadmium (Cd) is a carcinogenic bioaccumulative element. Both these metals are included in the priority pollutant list of the United States Environmental Protection Agency and in the WHO List of Chemicals of Major Public Health Concern, where contaminated foods and beverages are the most common pathways of exposure. The objective of this study was to determine total Cd and Pb levels in colored plastic utensils (cups, mugs, bowls, feeding bottles, and plates) for use by children and to measure the specific migration of these elements into beverages and foods. Total contaminant levels were determined using a handheld X-ray fluorescence analyzer. Specific migration tests were conducted using the simulant solutions acetic acid 3% (m/v) and water. Migration levels were determined by ICP-MS. Specific migration tests for Pb were also performed on commercially available samples (cola soft drink, orange juice, vinegar, and milk), with levels determined by graphite-furnace atomic absorption spectrometry (GF-AAS). A total of 674 utensils were analyzed in loco at major commercial centers in Greater São Paulo, of which 87 were purchased for containing Cd and Pb concentrations above permitted limits. Mean concentrations of the metals detected in the purchased utensils were 1110 ppm for Pb and 338 ppm for Cd. For specific migration assays, Pb levels were 187, 13, and 380 times above the permitted limit (0.01 mg.kg -1) for acetic acid, water, and orange juice, respectively. Cd levels were 50 and 2.4 times above the maximum permitted limit (0.005 mg.kg -1) for acetic acid and water, respectively. The districts where the utensils were purchased were grouped according to their social vulnerability index and compared using ANOVA. Pb levels were different between low and medium/high social vulnerability groups (p = 0.006). The findings corroborate the initial hypothesis that these utensils constitute a major source of exposure to PTEs such as Cd and Pb, pointing to the need for stricter regulation and inspection by the Brazilian regulatory agencies.
Показать больше [+] Меньше [-]Health risk assessment of endocrine disruptor bisphenol A leaching from plastic bottles of milk and soft drinks
2021
Farooq, Muhammad Umar | Jalees, Muhammad Irfan | Qurat-ul-Ain, | Hussain, Ghulam | Anis, Mehwish | Islam, Ummara
Bisphenol A (BPA) is of major concern to public health due to its toxic potential and xenoestrogenic endocrine-disrupting effect. One of the major sources of BPA comes from the plastic bottles used to pack milk and soft drinks. The purpose of the present study was to assess and compare the risk associated with BPA transfer from plastic bottles to milk and soft drinks being stored in summer and winter conditions. A sensitive and reliable method of solid phase extraction cartridge packed with multi-walled carbon nanotubes (MWCNTs) was employed. In milk samples (supplied in plastic bottles) of winter season, BPA levels were 0.17–0.32 mg/ kg. In milk samples of summer season, BPA levels were 0.77–1.59 mg/ kg. In soft drink samples of winter, BPA levels were between 0.14 and 0.3 mg/kg. While in 4-month-aged summer soft drink samples, BPA levels were 0.7–1.02 mg/kg of food. The daily exposure dose (DED) of BPA in milk samples of winter season was 1.42–2.67 μg/kg which was below the standard tolerable daily intake (TDI) of 50 μg of BPA/kg of body weight as per USEPA. The DED of BPA in milk samples of summer season was 5.58–10 μg/kg of body weight which was also less than TDI. For soft drink samples, BPA from winter samples was ranged from 1.17 to 1.67 μg/kg of body weight while for summer 4-month-aged samples was 2.5–7.08 μg/kg of body weight. Both types of samples were still less than TDI of BPA.
Показать больше [+] Меньше [-]Performance of metal-organic framework as an excellent sorbent for highly efficient and sensitive trace determination of anthracene in water and food samples
2020
Khani, Rouhollah | Ghalibafan, Maryam | Farrokhi, Alireza
Polycyclic aromatic hydrocarbons are a class of highly toxic and unremitting organic pollutants that are widely distributed in the natural environment. In this work, a metal-organic framework (MOF) designated as HKUST-1 [Cu₃(BTC)₂] was synthesized, characterized, and applied as a solid-phase extraction sorbent for the determination of a trace polycyclic aromatic hydrocarbon, anthracene (Ant) as model compound, in various real samples by spectrofluorimetry. The synthesized MOF exhibited large surface areas and high extraction ability, making it excellent candidate as sorbent for enrichment of trace anthracene. The effects of influential parameters on the performance of the dispersive micro-solid-phase extraction (Dμ-SPE) process, such as the initial anthracene concentration, pH, sorbent dosage, and shaking time, were investigated and optimized by the experiment design method. Under the optimized experimental conditions, good linearity in the range of 3–85 ng mL⁻¹ with correlation coefficient 0.997 and good sensitivity with low detection limit 0.5 ng mL⁻¹ for Ant was achieved. The method has been validated in the analysis of real tap water, soft drink, and vegetable juice samples with recoveries in the range of 86.33–103.00% and relative standard deviations in the range of 1.94–3.77%. The as-prepared HKUST-1 was used for at least four times without any obvious decline of extraction capability. The results of this study show the great potential of MOFs as sorbents in Dμ-SPE procedures for the separation and determination of trace Ant in complicated matrices.
Показать больше [+] Меньше [-]Pollution and energy reduction strategy in soft drink industries
2018
Muhammad, Nisar | Nafees, Mohammad | Hussain, Rahib | Khan, Muhammad Haya | Jehan, Shah | Ullah, Ubaid
The present study was conducted on soft drink industry with the objective to reduce wastewater pollution through end-of-pipe treatment and controlling energy loss through steam pipeline insulation approach. For this purpose, the main operation and manufacturing steps were examined. Wastewater was analyzed for 10 physicochemical parameters. Among these parameters, total dissolved solids (TDS), total suspended solids (TSS) and chemical oxygen demand (COD) were above their permissible level of Pakistan national environmental quality standards (Pak NEQS). For wastewater treatment, sedimentation, flocculation, coagulation and adsorption were tested. The active study reduces the pollution load up to 48%. After treatment, all the parameters were below the Pak NEQS level. To reduce the energy loss and economic benefits, the steam pipeline system was galvanized using glass wool, sheet and paper. Through galvanizing, 91.4% of energy was recovered and reduced an extra cost of 91.5%. The net saving of energy and cost are 312 GJ and114098 Rs/year, respectively. The study recommends end off pipe treatment and insulation of bare pipeline system for soft drink industries.
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