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1

Evaluation of the Distribution of Heavy Metals and Arsenic in Inland Wetlands (Peru) Using Multivariate Statistical Methods

100%

Custodio M. , Peñaloza R.

Ecological Engineering & Environmental Technology

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2021

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tom Vol. 22, iss. 3

104--111

EN

Heavy metals in the environment circulate among the different compartments and can accumulate, convert into organic complexes and biomagnify in the food chain. The objective of this study was to evaluate the distribution of heavy metals and arsenic in inland wetlands using multivariate statistical methods. Samples of water, sediment and aquatic vegetation were collected at 48 sampling sites established in the Paca and Tragadero lagoon wetlands. The determination of heavy metals and arsenic was carried out using the flame atomic absorption spectrophotometry method. The decreasing order of heavy metal and arsenic concentration in sediment was Fe>Zn>Pb>As, in water it was Zn>Fe>Pb>As and in S. californicus it was Zn>Fe>Pb>As. Redundancy analysis (RDA) indicated that there are significant differences in heavy metal and arsenic concentrations in sediment between ponds and between sampling sites. Generalized linear model (GLM) analysis on vegetables indicated that the concentrations of heavy metals and arsenic in the vegetable increase as a function of their concentration in sediment.

2

Evaluation of Surface Sediment Quality in Rivers with Fish Farming Potential (Peru) Using Indicators of Contamination, Accumulation and Ecological Risk of Heavy Metals and Arsenic

70%

Custodio M. , Fow A. , Peñaloza R. , Chanamé F. , Cano D.

Journal of Ecological Engineering

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2021

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tom Vol. 22, nr 5

78--87

EN

Surface sediment quality of potential rivers in Peru was evaluated using indicators of contamination, accumulation and ecological risk of heavy metals and As. Surface sediment samples were collected at 54 sampling sites in the Tishgo and Chia rivers during 2018. The determination of Cu, Pb, Zn and As was performed by flame atomic absorption spectrophotometry. The results revealed the decreasing order of the mean concentrations of heavy metals and As in the Chia River of Zn > Cu > As > Pb and Tishgo of Zn > Pb > As > Cu. The PLI for the Tishgo River were greater than one (PLI > 1) denoting the deterioration it has been experiencing. In the Chia River, 60% of the sampling sites indicated no appreciable contamination by these elements (PLI < 1). The Igeo values of As in both rivers showed a state of contamination, from moderately to severely contaminated. In the Tishgo River the potential ecological risk varied from low to moderate and in the Chia River from low to considerable. Finally, this study reveals the applicability of the evaluation indexes of contamination, accumulation and potential ecological risk of toxic metals so that special control measures can be adopted.

3

Variability of the Water Quality Characterizing High Andean Lagoons for Tourist Use Evaluated Through Multivariate Statistical Methods, Junín, Peru

70%

Custodio M. , Miranda G. , Peñaloza R. , De la Cruz H. , Chanmé F.

Journal of Ecological Engineering

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2019

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tom Vol. 20, nr 8

1--11

EN

The spatial-temporal variability characterizing the water quality of high Andean lagoons for tourist use was evaluated using multivariate statistical methods during 2017 and 2018. The water samples were collected from 14 sampling sites, with three replicates each. The water quality indicators determined were: pH, temperature, DO, COD, BOD5, P, N, Fe, Cu, Cr, Cd, Pb, Zn and chlorophyll-a. The flat cluster analysis (k R cluster) according to Ward’s algorithm showed six significantly differentiated groups (α=0.01). In turn, the real similarity profile (SIMPROF) moves markedly away from the obtained low permutation with a large excess of Euclidean similarity with a Pi value of 0.627. The PCA showed that the first two components recommended by the sedimentation analysis (Scree test) indicated 61.52% of the total variation of the observations. According to the Spearman range correlation selection criterion, the variables that best interpret the sample distributions are COD, DTS, P, Cd and Zn with a correlation of 0.893, the DTS being the most important variable with a correlation value of 0.795. The PERMANOVA analysis according to the flat cluster factor indicated that at least one of the groups is different from the others in relation to the levels of physicochemical characteristics studied. Therefore, all the configured groups are statistically different, demonstrating that each lagoon is different in relation to its physicochemical indicators, according to the season in which it is found.

4

Heavy Metals and Arsenic in Water, Sediment and the Muscle of Oncorhynchus Mykiss from the Tishgo River in the Central Andes of Peru

70%

Condor A. , Custodio M. , Chanamé F. , Cuadrado W. , Peñaloza R.

Journal of Ecological Engineering

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2021

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tom Vol. 22, nr 4

156--166

EN

The concentration of Cu, Pb, Zn and As in water, sediment and muscle of Oncorhynchus mykiss from the Tishgo river in the central Andes of Peru were analyzed. The water, sediment and fish samples were collected from 36 sites in three sampling sectors. The analytical determination was performed by flame atomic absorption spectrophotometry. The mean Pb concentrations in the water from the three sampling sectors showed significant differences (p < 0.05) which exceeded the values of the Peruvian standard and the WHO. The mean concentrations of Cu, Pb and As in sediment did not present significant differences (p > 0.05) in the three sectors evaluated. The redundancy analysis (RDA) revealed that the concentrations of As and Pb in water, and Cu, As and Zn in sediment significantly influence the concentration of these elements in the O. mykiss muscle. The mean concentrations of Cu, Pb, Zn and As in the O. mykiss muscle were lower than those established by international regulations. Therefore, the concentrations of heavy metals and As recorded in this study do not represent a threat to the consumption of O. mykiss from the Tishgo river.

5

Heavy Metals and Arsenic in Soil and Cereal Grains and Potential Human Risk in the Central Region of Peru

70%

Custodio M. , Peñaloza R. , Orellana E. , Aguilar-Cáceres M. A. , Maldonado-Oré E. M.

Journal of Ecological Engineering

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2021

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tom Vol. 22, nr 1

206--220

EN

The objective of this study was to analyze the content of heavy metals and arsenic in soil and cereal grains as well as to evaluate the possible human risk in the central region of Peru. The soil samples of corn and barley grains were collected from seven agricultural zones and the concentrations of Cu, Fe, Pb, Zn and As were determined with the method of atomic absorption flame spectrophotometry. PERMANOVA showed that the effect of the type of crop and the sampling zone significantly influence the concentrations of heavy metals and As in soil and corn and barley grains (p < 0.05). PCA for heavy metals and As in soil and grain samples of the cereals studied showed that the first two main components represented 81.03% and 94.77% of the total variance, respectively. Hazard Quotient (HQ) for ingestion was the most significant. The HQ values of Pb and As in crop soils indicated that detrimental health effects are unlikely (HQ < 1). The soil hazard index (HI) values of both crops did not exceed the threshold value of 1 (HI < 1). The carcinogenic risk level (CR) of As from ingestion of corn and barley crop soils contaminated by As was higher in children than in farmers and adults. The bioconcentration factor (BCF) of As was higher in barley grains than in corn grains. The THQ of As exceeded the target value of 1 in 100% of the barley and corn sampling sites. The RC of As in grains exceeded the acceptable risk level of 10–6 in all sampling zones.

6

Treatment of Hospital Wastewater Using Activated Sludge with Extended Aeration

61%

Custodio M. , Cuadrado-Campó W. , Peñaloza R. , Vicuña-Orihuela C. , Torres-Gutiérrez E. , Orellana E.

Journal of Ecological Engineering

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2022

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tom Vol. 23, nr 11

24--32

EN

Hospital wastewater is of a complex nature and is generally discharged into urban sewage systems. This study evaluated the removal efficiency of organic and biological contaminants from a hospital wastewater treatment plant using extended aeration activated sludge. The study was conducted at a treatment plant scale, with 14 hours of feed. The plant consists of a pre-filter, a collector and crumbler tank, a homogenization tank, two biological reactors of 80 000 liters capacity each, two settlers and a contact disinfection chamber. Three flow rates of 3 L/s, 4 L/s and 5 L/s were tested in each biological reactor, with application of three concentrations of residual chlorine with sodium hypochlorite to the effluent of the settling tanks (0.3 ppm, 0.4 ppm and 0.5 ppm). The removal efficiency of suspended solids varied according to flow rate. The reactor with a flow rate of 3 L/s and 0.5 ppm of residual chlorine achieved the highest removal of suspended solids (91.95%), biological oxygen demand (97.52%) and fecal coliforms (99.99%). Finally, the quality of the hospital wastewater is within the limits of the national and international environmental quality thresholds.

7

Heavy Metal Accumulation in Sediment and Removal Efficiency in the Stabilization Ponds with the Hydrocotyle ranunculoides Filter

61%

Custodio M. , Orellana-Mendoza E. , Peñaloza R. , De la Cruz-Solano H. , Bulege-Gutiérrez W. , Quispe-Mendoza R.

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2020

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tom Vol. 21, nr 5

72--79

EN

The heavy metal accumulation in the sediment and removal efficiency in stabilization ponds with Hydrocotyle ranunculoides filter were evaluated. Sediment and water were sampled in June, July and August 2018. The sediment sampling for each lagoon was conducted at three sites forming a composite sample. The water samples were collected in the tributary and effluent pipelines to determine the heavy metal concentration and removal efficiency by Hydrocotyle ranunculoides. The determination of heavy metals was performed with the method of atomic flame absorption spectrophotometry. The mean concentration of heavy metals in the sediment, in a descending order, was: Fe > Zn > Pb > Cu > Cd. The concentrations of these metals ranged from 998.0 to 1365.02, from 488.01 to 600.30, from 88.23 to 95.01, from 1.47 to 1.53 and from 0.01 to 0.13 mg/Kg, respectively. In the four stabilization ponds, the pollution factor values for Cd, Cu and Fe qualified as low pollution factor. While for Zn and Pb, they qualified as moderate pollution factors. The heavy metal removal rates from the water varied by metal.