Examinando por Autor "Churango Valdez, Javier"

Mostrando 1 - 6 de 6

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Determinación cuantitativa de arsénico, cobre, níquel y plomo en margarinas y mantequillas expendidas en el mercado de Caquetá – San Martin de Porres – periodo de Junio–Octubre 2015
(Universidad Privada Norbert Wiener, 2015) Altamirano Verastegui, Luis Antonio; Cruz Quispe, Edwin; Churango Valdez, Javier
Margarine and butter are widely consumed products, being among the most commonly used cooking ingredients alongside oil. Investigating their quality is of great importance from both health and commercial perspectives. Heavy metals pose a serious risk as they tend to bioaccumulate in biological organisms, increasing their concentration and potentially causing harmful effects on internal organs, the nervous system, kidneys, liver, and lungs. For this reason, a study was conducted to quantitatively determine the levels of arsenic, copper, nickel, and lead in margarines and butters sold at the Caquetá market in San Martín de Porres during the period June–October 2015, using atomic absorption spectrophotometry. Seventeen samples of margarines and butters were collected for analysis. The results showed that the average concentrations of arsenic, copper, nickel, and lead were: As 0.07 mg/kg, Cu 0.09 mg/kg, Ni 0.28 mg/kg, and Pb 0.11 mg/kg. These results were compared against the Codex Alimentarius, the Ecuadorian Technical Standard, and the Venezuelan Technical Standard.
Acceso abierto
Determinación cuantitativa de cadmio, plomo y cobre en hígado de ganado bovino expendidos en mercados: Central, 03 de Febrero y Camal de Yerbateros durante setiembre del 2014
(Universidad Privada Norbert Wiener, 2015) Cristobal Palomares, Jhovani Walter; Cruz Orihuela, Ruth Rosalyn; Churango Valdez, Javier
The objective of this study was to quantitatively determine the concentration of cadmium, lead, and copper in bovine liver sold at the Central Market, 03 de Febrero, and the Yerbateros Slaughterhouse during September 2014. The method used for the quantification of these metals was Atomic Absorption Spectrophotometry with a graphite furnace. The cadmium levels found in the twenty-five liver samples showed an average of 9.59 mg Cd/kg liver, with a minimum value of 5.89 mg/kg and a maximum value of 14.11 mg/kg. Lead levels in the samples showed an average of 52.26 mg Pb/kg liver, with a minimum of 28.34 mg/kg and a maximum of 75.85 mg/kg. Finally, copper levels in the samples showed an average of 1.70 mg Cu/kg liver, with a minimum of 0.78 mg/kg and a maximum of 3.09 mg/kg. The results indicate that the bovine liver samples exceed the established cadmium, lead, and copper limits according to the Official Mexican Standard and European Union regulations. Therefore, it is concluded that the liver samples contain Cd, Pb, and Cu above the permitted levels according to international standards, posing a potential health risk for consumers.
Acceso abierto
Determinación de liberación cuantitativa de plomo y cadmio en utensilios cerámicos (platos tendidos y hondos menor a un litro) comercializados en Lima Metropolitana en el período mayo–octubre 2014
(Universidad Privada Norbert Wiener, 2015) Meza Vega, Candy Maruja; Sánchez Campos, Jobita; Churango Valdez, Javier
Consumers are generally unaware of the toxicity of metals used in the production or decoration of ceramic ware, and even less so of the release of lead and cadmium that occurs through continuous use of ceramic plates in contact with food. Due to this issue, the present study was conducted on the “Quantitative determination of lead and cadmium release in ceramic utensils (flat and deep plates under one liter) commercialized in Metropolitan Lima during the period May–October 2014.” A total of 10 samples of deep plates and 10 samples of flat plates were analyzed. For lead in flat plates, the minimum concentration found was 1.02 mg/dm², the maximum 2.05 mg/dm², with an average release of 1.53 mg/dm². In deep plates, the minimum concentration was 2.55 mg/L, the maximum 9.74 mg/L, with an average lead release of 4.48 mg/L. For cadmium in flat plates, the minimum concentration was 0.10 mg/dm², the maximum 0.29 mg/dm², with an average release of 0.17 mg/dm². In deep plates, the minimum concentration was 0.12 mg/L, the maximum 0.71 mg/L, with an average release of 0.29 mg/L. Lead and cadmium levels were determined using the atomic absorption spectrophotometric method.
Acceso abierto
Determinación de plomo y cadmio en apium graveolens (apio) y allium ampeloprasum L.var. porrum (poro) expendidos en el mercado central Santa Anita durante el período de agosto 2014 a febrero 2015
(Universidad Privada Norbert Wiener, 2015) Guevara Santos, Nelly; Peralta Najarro, Nemia; Churango Valdez, Javier
The present research was conducted to evaluate the concentration of lead and cadmium in Apium graveolens (celery) and Allium ampeloprasum L. var. porrum (leek) sold at the Central Santa Anita market during the period August 2014 to February 2015. The concentration of heavy metals was determined using the Atomic Absorption Spectrophotometry method. In celery samples, lead levels averaged 0.20 ppm, with a minimum of 0.13 ppm and a maximum of 0.33 ppm, while cadmium levels averaged 0.23 ppm, with a minimum of 0.15 ppm and a maximum of 0.59 ppm. In leek samples, lead levels averaged 0.10 ppm, with a minimum of 0.05 ppm and a maximum of 0.18 ppm, whereas cadmium levels averaged 0.38 ppm, with a minimum of 0.18 ppm and a maximum of 0.59 ppm. The results indicate that both Apium graveolens (celery) and Allium ampeloprasum L. var. porrum (leek) exceeded the maximum limits established by the Codex Alimentarius for lead and cadmium. Therefore, it can be concluded that these vegetables contain high levels of heavy metals, representing a potential health risk for consumers.
Acceso abierto
Determinación de plomo, cadmio y arsénico en hígados de pollo expendidos en el mercado Caquetá – San Martín de Porres período de marzo–julio 2015
(Universidad Privada Norbert Wiener, 2015) Espinoza Valdiviezo, Magali Karina; Suarez Zulueta, Sandra; Churango Valdez, Javier
The objective of this study was to quantitatively determine the levels of lead, cadmium, and arsenic in chicken liver sold by poultry vendors at the Caquetá Market during the period from March to July 2015. Samples were collected from 30 poultry vendors, taking one liver sample per vendor, and analyzed using Atomic Absorption Spectrophotometry with a graphite furnace for lead and cadmium. Arsenic was analyzed using Atomic Absorption Spectrophotometry with hydride generation. The results showed that the average lead concentration was 0.4326 mg/kg, below the limits established by Mercosur, the European Union, and the Codex Alimentarius; however, lead concentrations in 7 out of 30 samples (23%) exceeded the established limit. The average cadmium concentration was 0.4403 mg/kg, also below the limits established by Mercosur, the European Union, and the Codex Alimentarius; nevertheless, cadmium concentrations in 10 out of 30 samples (33%) exceeded the established limit. The average arsenic concentration was 0.858 mg/kg, above the limit established by Mercosur, with 7 out of 30 samples (23%) exceeding the limit. In conclusion, the analyzed samples contain heavy metals, posing a potential risk to consumers and representing a threat to public health.
Acceso abierto
Determinación de plomo, cadmio y manganeso en sedimentos de hojas de Sauce "Salix alba" en las avenidas Abancay y Tacna, Lima – Noviembre 2014–enero 2015
(Universidad Privada Norbert Wiener, 2015) Cajas Regal, Diana Rebeca; Evangelista Doria, Luisa Celina; Churango Valdez, Javier
The concentration of lead, cadmium, and manganese was determined in leaf sediments of Salix alba (willow) collected from Tacna and Abancay avenues between November 2014 and January 2015. A total of 86 samples were analyzed, 44 from Abancay Avenue and 42 from Tacna Avenue, using flame atomic absorption spectrophotometry. The results for lead and cadmium were compared with the Environmental Quality Standards for soils (ECAS 2013) in Peru and with U.S. EPA standards (USEPA 2002). Manganese levels were compared with the reference values of the Agency for Toxic Substances and Disease Registry (ATSDR 2012). Findings showed that 95% of samples from Abancay Avenue and 100% from Tacna Avenue exceeded the Peruvian permissible limits for lead in residential/park soils. For cadmium, 100% of Abancay samples were above the standard. Compared with U.S. EPA human health risk levels, 18% of Abancay and 10% of Tacna samples exceeded the limits. No manganese sample surpassed the values established by ATSDR. It is therefore recommended to continue urban tree-cleaning programs, as they help reduce environmental contamination by heavy metals.