Toxic Elements in Soil and Rice in Ecuador
Abstract
:1. Introduction
2. Materials and Methods
2.1. Sampling and Sample Preparation
2.2. Physicochemical Characteristics and Soil Texture
2.3. Total Metal(oids) Content in Soils
2.4. Metal Bioavailability in Soils
2.5. Sequential Extraction of Metal(oids)
2.6. Total Metal Content in Rice Plants and Grain
2.7. Statistical Analysis
3. Results and Discussion
3.1. Soil Composition and Properties
3.2. Total and Partitioning of Toxic Elements
3.3. Toxic Elements Uptake by Rice Plants
4. Conclusions
Supplementary Materials
Author Contributions
Funding
Institutional Review Board Statement
Informed Consent Statement
Data Availability Statement
Conflicts of Interest
References
- Kögel-Knabner, I.; Amelung, W.; Cao, Z.; Fiedler, S.; Frenzel, P.; Jahn, R.; Kalbitz, K.; Kölbl, A.; Schloter, M. Biogeochemistry of paddy soils. Geoderma 2010, 157, 1–14. [Google Scholar] [CrossRef]
- Cheajesadagul, P.; Shiowatana, J.; Siripinyanond, A.; Szpunar, J. Chapter 24—Rice. In Food Protected Designation of Origin; de la Guardia, M., Gonzálvez, A.B.T.-C.A.C., Eds.; Elsevier: Amsterdam, The Netherlands, 2013; pp. 623–655. [Google Scholar]
- FAOSTAT. Faostat: Food Balance Sheets; Food and Agriculture Organization of the United Nations: Rome, Italy, 2018; Available online: https://faostat.fao.org/beta/en/#data/FBS (accessed on 1 January 2021).
- FAO. Soil Pollution: A Hidden Reality—Main Report; Food and Agriculture Organization of the United Nations: Rome, Italy; Global Soil Partnership Food and Agriculture Organization: Rome, Italy, 2018. [Google Scholar]
- Tian, K.; Huang, B.; Xing, Z.; Hu, W. Geochemical baseline establishment and ecological risk evaluation of heavy metals in greenhouse soils from Dongtai. China. Ecol. Indic. 2017, 72, 510–520. [Google Scholar] [CrossRef]
- Chen, Y.; Huang, B.; Hu, W.; Weindorf, D.C.; Liu, X.; Niedermann, S. Assessing the risks of trace elements in environmental materials under selected greenhouse vegetable production systems of China. Sci. Total Environ. 2014, 470–471, 1140–1150. [Google Scholar] [CrossRef]
- Kwon, J.C.; Nejad, Z.D.; Jung, M.C. Arsenic and heavy metals in paddy soil and polished rice contaminated by mining activities in Korea. CATENA 2017, 148, 92–100. [Google Scholar] [CrossRef]
- Sarwar, N.; Imran, M.; Shaheen, M.R.; Ishaque, W.; Kamran, M.A.; Matloob, A.; Rehim, A.; Hussain, S. Phytoremediation strategies for soils contaminated with heavy metals: Modifications and future perspectives. Chemosphere 2017, 171, 710–721. [Google Scholar] [CrossRef]
- Syu, C.; Huang, C.; Jiang, P.; Lee, C.; Lee, D. Arsenic accumulation and speciation in rice grains influenced by arsenic phytotoxicity and rice genotypes grown in arsenic-elevated paddy soils. J. Hazard. Mater. 2015, 286, 179–186. [Google Scholar] [CrossRef] [PubMed]
- Naseri, M.; Vazirzadeh, A.; Kazemi, R.; Zaheri, F. Concentration of some heavy metals in rice types available in Shiraz market and human health risk assessment. Food Chem. 2015, 175, 243–248. [Google Scholar] [CrossRef] [PubMed]
- Raber, G.; Stock, N.; Hanel, P.; Murko, M.; Navratilova, J.; Francesconi, K.A. An improved HPLC–ICPMS method for determining inorganic arsenic in food: Application to rice, wheat and tuna fish. Food Chem. 2012, 134, 524–532. [Google Scholar] [CrossRef]
- Signes-Pastor, A.J.; Carey, M.; Carbonell-Barrachina, A.A.; Moreno-Jiménez, E.; Green, A.J.; Meharg, A.A. Geographical variation in inorganic arsenic in paddy field samples and commercial rice from the Iberian Peninsula. Food Chem. 2016, 202, 356–363. [Google Scholar] [CrossRef] [Green Version]
- Zhang, J.; Li, H.; Zhou, Y.; Dou, L.; Cai, L.; Mo, L.; You, J. Bioavailability and soil-to-crop transfer of heavy metals in farmland soils: A case study in the Pearl River Delta, South China. Environ. Pollut. 2018, 235, 710–719. [Google Scholar] [CrossRef]
- Inaba, T.; Kobayashi, E.; Suwazono, Y.; Uetani, M.; Oishi, M.; Nakagawa, H.; Nogawa, K. Estimation of cumulative cadmium intake causing Itai–itai disease. Tox. Lett. 2005, 159, 192–201. [Google Scholar] [CrossRef]
- Rahman, M.A.; Rahman, I.M.M.; Hasegawa, H. Cooking: Effects on Dietary Exposure to Arsenic from Rice and Vegetables. In Encyclopedia of Environmental Health; Nriagu, J.O., Ed.; Elsevier: Burlington, VT, USA, 2011; pp. 248–255. [Google Scholar]
- Bundschuh, J.; Litter, M.I.; Parvez, F.; Román-Ross, G.; Nicolli, H.B.; Jean, J.; Liu, C.; López, D.; Armienta, M.A.; Guilherme, L.R.G.; et al. One century of arsenic exposure in Latin America: A review of history and occurrence from 14 countries. Sci. Total Environ. 2012, 429, 2–35. [Google Scholar] [CrossRef]
- Bundschuh, J.; Nath, B.; Bhattacharya, P.; Liu, C.; Armienta, M.A.; Moreno López, M.V.; Lopez, D.L.; Jean, J.; Cornejo, L.; Lauer Macedo, L.F.; et al. Arsenic in the human food chain: The Latin American perspective. Sci. Total Environ. 2012, 429, 92–106. [Google Scholar] [CrossRef]
- Cumbal, L.; Vallejo, P.; Rodriguez, B.; Lopez, D. Arsenic in geothermal sources at the north-central Andean region of Ecuador: Concentrations and mechanisms of mobility. Environ. Earth Sci. 2010, 61, 299–310. [Google Scholar] [CrossRef]
- De la Torre, E.; Guevara, A.; Muñoz, G.; Criollo, E. Estudio de Aguas Superficiales y Sedimentos de la Cuenca de Los Ríos Sucus; Unpublished Report for the Ecuadorian Congress; Tambo y Papallacta: Quito, Ecuador, 2004. [Google Scholar]
- Appleton, J.D.; Williams, T.M.; Orbea, H.; Carrasco, M. Fluvial Contamination Associated with Artisanal Gold Mining in the Ponce Enríquez, Portovelo-Zaruma and Nambija Areas, Ecuador. Water Air Soil Pollut. 2001, 131, 19–39. [Google Scholar] [CrossRef]
- Nunes, L.M.; Otero, X. Quantification of health risks in Ecuadorian population due to dietary ingestion of arsenic in rice. Environ. Sci. Pollut. Res. Int. 2017, 24, 27457–27468. [Google Scholar] [CrossRef] [PubMed]
- Pozo, W.; Sanfeliu, T.; Carrera, G. Metales pesados en humedales de arroz en la cuenca baja del río Guayas. MASKANA 2011, 2, 17–30. [Google Scholar] [CrossRef]
- Otero, X.L.; Ferreira, T.O.; Huerta-Díaz, M.A.; Partiti, C.S.M.; Souza, V.; Vidal-Torrado, P.; Macías, F. Geochemistry of iron and manganese in soils and sediments of a mangrove system, Island of Pai Matos (Cananeia—SP, Brazil). Geoderma 2009, 148, 318–335. [Google Scholar] [CrossRef]
- Meharg, A.A.; Rahman, M.M. Arsenic Contamination of Bangladesh Paddy Field Soils: Implications for Rice Contribution to Arsenic Consumption. Environ. Sci. Technol. 2003, 37, 229–234. [Google Scholar] [CrossRef]
- TULSMA. Texto Unificado de Legislación Secundaria: Libro VI. De la Calidad Ambiental. Anexo I. Norma de Calidad Ambiental y Descarga de Efluentes: Recurso Agua, Criterios de Remediación Para Suelos Agrícolas. Criterios Generales Para la Descarga de Efluentes; Presidencia de la República: Quito, Ecuador, 2015. [Google Scholar]
- Ewers, U. Standards, guidelines and legislative regulatory concerning metals and their compounds. In Metals and Their Compounds in the Environment; Merian, E., Ed.; VCH Publishers: Weinheim, Germany, 1991; pp. 707–711. [Google Scholar]
- Kabata-Pendias, A. Agricultural Problems Related to Excessive Trace Metal Contents of Soils. In Heavy Metals: Problems and Solutions; Förstner, U., Salomons, W., Mader, P., Eds.; Springer: Berlin/Heidelberg, Germany, 1995; pp. 3–18. [Google Scholar]
- Yamaguchi, N.; Ohkura, T.; Takahashi, Y.; Maejima, Y.; Arao, T. Arsenic Distribution and Speciation near Rice Roots Influenced by Iron Plaques and Redox Conditions of the Soil Matrix. Environ. Sci. Technol. 2014, 48, 1549–1556. [Google Scholar] [CrossRef]
- Otero, X.L.; Tierra, W.; Atiaga, O.; Guanoluisa, D.; Nunes, L.M.; Ferreira, T.O.; Ruales, J. Arsenic in rice agrosystems (water, soil and rice plants) in Guayas and Los Ríos provinces. Ecuador. Sci. Total Environ. 2016, 573, 778–787. [Google Scholar] [CrossRef] [Green Version]
- Yu, H.; Li, F.; Liu, C.; Huang, W.; Liu, T.; Yu, W. Chapter Five—Iron Redox Cycling Coupled to Transformation and Immobilization of Heavy Metals: Implications for Paddy Rice Safety in the Red Soil of South China. Adv. Agron. 2016, 137, 279–317. [Google Scholar]
- Du, J.; Yan, C.; Li, Z. Formation of iron plaque on mangrove Kandalar, Obovata (S.L.) root surfaces and its role in cadmium uptake and translocation. Mar. Pollut. Bull. 2013, 74, 105–109. [Google Scholar] [CrossRef] [PubMed]
- Zhao, K.; Liu, X.; Zhang, W.; Xu, J.; Wang, F. Spatial dependence and bioavailability of metal fractions in paddy fields on metal concentrations in rice grain at a regional scale. J. Soils Sediments 2011, 11, 1165. [Google Scholar] [CrossRef]
- Li, H.; Luo, N.; Li, Y.W.; Cai, Q.Y.; Li, H.Y.; Mo, C.H.; Wong, M.H. Cadmium in rice: Transport mechanisms, influencing factors, and minimizing measures. Environ. Poll. 2017, 224, 622–630. [Google Scholar] [CrossRef]
- Suriyagoda, L.D.B.; Dittert, K.; Lambers, H. Mechanism of arsenic uptake, translocation and plant resistance to accumulate arsenic in rice grains. Agric. Ecosyst. Environ. 2018, 253, 23–37. [Google Scholar] [CrossRef]
- Gu, J.; Zhou, H.; Tang, H.; Yang, W.; Zeng, M.; Liu, Z.; Peng, P.; Liao, B. Cadmium and arsenic accumulation during the rice growth period under in situ remediation. Ecotoxicol. Environ. Saf. 2019, 171, 451–459. [Google Scholar] [CrossRef]
- Van der Zee, C.; Slomp, C.P.; Rancourt, D.G.; de Lange, G.J.; Van Raaphorst, W. A Mössbauer spectroscopic study of the iron redox transition in eastern Mediterranean sediments. Geochim. Cosmochim. Acta 2004, 69, 441–453. [Google Scholar] [CrossRef]
- EU. Maximum Levels for Certain Contaminants in Food; European Commission Regulation (EC) No 1881/2006 of 19 December 2006; EU: Brussels, Belgium, 2006. [Google Scholar]
- Xu, B.; Wang, F.; Zhang, Q.; Lan, Q.; Liu, C.; Guo, X.; Cai, Q.; Chen, Y.; Wang, G.; Ding, J. Influence of iron plaque on the uptake and accumulation of chromium by rice (Oryza sativa L.) seedlings: Insights from hydroponic and soil cultivation. Ecotoxicol. Environ. Saf. 2018, 162, 51–58. [Google Scholar] [CrossRef]
- Chaney, R.L. Health risks associated with toxic metals in municipal sludge. In Sludge—Health Risks of Land Application; Bitton, G., Damron, B.L., Edds, G.T., Davidson, J.M., Eds.; Ann Arbor Science Publications: Ann Arbor, MI, USA, 1980; pp. 59–83. [Google Scholar]
- USEPA. Framework for Metals Risk Assessment; US Environmental Protection Agency: Washington, DC, USA, 2007.
- Zhang, Q.; Chen, H.; Xu, C.; Zhu, H.; Zhu, Q. Heavy metal uptake in rice is regulated by pH-dependent iron plaque formation and the expression of the metal transporter genes. Environ. Exp. Bot. 2019, 162, 392–398. [Google Scholar] [CrossRef]
- Baker, A.J.M. Accumulators and Excluders—Strategies in the Response of Plants to Heavy Metals. J. Plant Nutr. 1981, 3, 643–654. [Google Scholar] [CrossRef]
- Du, F.; Yang, Z.; Liu, P.; Wang, L. Accumulation, translocation, and assessment of heavy metals in the soil-rice systems near a mine-impacted region. Environ. Sci. Pollut. Res. 2018, 25, 32221–32230. [Google Scholar] [CrossRef]
- Gupta, D.K.; Chatterjee, S.; Datta, S.; Veer, V.; Walther, C. Role of phosphate fertilizers in heavy metal uptake and detoxification of toxic metals. Chemosphere 2014, 8, 134–144. [Google Scholar] [CrossRef]
- Ali, W.; Mao, K.; Zhang, H.; Junaid, M.X.N.; Rasool, A.; Feng, X.; Yang, Z. Comprehensive review of the basic chemical behaviours, sources, processes, and endpoints of trace element contamination in paddy soil-rice systems in rice-growing countries. J. Hazard. Mater. 2020, 397, 122720. [Google Scholar] [CrossRef]
- Gilbert, B.; Frenzel, P. Rice roots and CH4 oxidation: The activity of bacteria, their distribution and the microenvironment. Soil Biol. Biochem. 1998, 30, 1903–1916. [Google Scholar] [CrossRef]
- Taylor, G.J.; Crowder, A.A. Uptake and accumulation of copper, nickel, and iron by Typha latifolia grown in solution culture. Can. J. Bot. 1983, 61, 1825–1830. [Google Scholar] [CrossRef]
- Zhang, X.; Zhang, F.; Mao, D. Effect of iron plaque outside roots on nutrient uptake by rice (Oryza sativa L.). Zinc uptake by Fe-deficient rice. Plant Sci. 1998, 202, 33–39. [Google Scholar]
- Liu, Y.; Zhou, T.; Crowley, D.; Li, L.; Liu, D.; Zheng, J.; Yu, X.; Pan, G.; Hussain, Q.; Zhang, X.; et al. Decline in topsoil microbial quotient, fungal abundance and C utilization efficiency of rice paddies under heavy metal pollution across South China. PLoS ONE 2012, 7, e38858. [Google Scholar] [CrossRef] [PubMed] [Green Version]
- Ye, Z.; Baker, A.J.M.; Wong, M.; Willis, A.J. Zinc, lead and cadmium accumulation and tolerance in Typha latifolia as affected by iron plaque on the root surface. Aquat Bot. 1998, 61, 55–67. [Google Scholar] [CrossRef]
- Liu, H.J.; Zhang, J.L.; Zhang, F.S. Role of iron plaque in Cd uptake by and translocation within rice (Oryza sativa L.) seedlings grown in solution culture. Environ. Exp. Bot. 2007, 59, 314–320. [Google Scholar] [CrossRef]
- Hu, Y.; Huang, Y.Z.; Liu, Y.X. Influence of iron plaque on chromium accumulation and translocation in three rice (Oryza sativa L.) cultivars grown in solution culture. Chem. Ecol. 2014, 30, 29–38. [Google Scholar] [CrossRef]
- Cao, X.; Ma, L.Q.; Shiralipour, A. Effects of compost and phosphate amendments on arsenic mobility in soils and arsenic uptake by the hyperaccumulator, Pteris vittata L. Environ. Pollut. 2003, 126, 157–167. [Google Scholar] [CrossRef]
- Peralta-Videa, J.R.; Lopez, M.L.; Narayan, M.; Saupe, G.; Gardea-Torresdey, J. The biochemistry of environmental heavy metal uptake by plants: Implications for the food chain. Int. J. Biochem. Cell Biol. 2009, 41, 1665–1677. [Google Scholar] [CrossRef] [PubMed]
- Sharma, S.; Kaur, I.; Nagpal, A.K. Assessment of arsenic content in soil, rice grains and groundwater and associated health risks in human population from Ropar wetland, India, and its vicinity. Environ. Sci. Pollut. Res. 2017, 24, 18836–18848. [Google Scholar] [CrossRef]
- Samal, A.C.; Bhattacharya, P.; Biswas, P.; Maity, J.P.; Bundschuh, J.; Santra, S.C. Variety-specific arsenic accumulation in 44 different rice cultivars (O. sativa L.) and human health risks due to co-exposure of arsenic-contaminated rice and drinking water. J. Hazard. Mater. 2021, 407, 124804. [Google Scholar] [CrossRef]
- Singh, J.; Upadhyay, S.K.; Pathak, R.K.; Gupta, V. Accumulation of heavy metals in soil and paddy crop (Oryza sativa), irrigated with water of Ramgarh Lake, Gorakhpur, UP, India. Toxicol. Environ. Chem. 2011, 93, 462–473. [Google Scholar] [CrossRef]
- Tariq, S.R.; Rashid, N. Multivariate analysis of metal levels in paddy soil, rice plants, and rice grains: A case study from Shakargarh, Pakistan. J. Chem. 2013, 2013, 539251. [Google Scholar] [CrossRef]
- Luo, C.; Yang, R.; Wang, Y.; Li, J.; Zhang, G.; Li, X. Influence of agricultural practice on trace metals in soils and vegetation in the water conservation area along the East River (Dongjiang River), South China. Sci. Total Environ. 2012, 431, 26–32. [Google Scholar] [CrossRef] [PubMed]
- Cao, H.; Chen, J.; Zhang, J.; Zhang, H.; Qiao, L.; Men, Y. Heavy metals in rice and garden vegetables and their potential health risks to inhabitants in the vicinity of an industrial zone in Jiangsu, China. J. Environ. Sci. 2010, 22, 1792–1799. [Google Scholar] [CrossRef]
- Xie, W.J.; Che, L.; Zhou, G.Y.; Yang, L.N.; Hu, M.Y. The bioconcentration ability of heavy metal research for 50 kinds of rice under the same test conditions. Environ. Monit. Assess. 2016, 188, 675. [Google Scholar] [CrossRef] [Green Version]
- Hseu, Z.Y.; Lai, Y.J. Nickel accumulation in paddy rice on serpentine soils containing high geogenic nickel contents in Taiwan. Environ. Geochem. Health 2017, 39, 1325–1334. [Google Scholar] [CrossRef] [PubMed]
- Blaylock, M.J.; Huang, J.W. Phytoextraction of metals. In Phytoremediation of Toxic Metals: Using Plants to Clean Up the Environment; Raskin, I., Ensley, B.D., Eds.; John Wiley: New York, NY, USA, 2000; pp. 53–71. [Google Scholar]
- Liu, J.; Li, K.; Xu, J.; Zhang, Z.; Ma, T.; Lu, X.; Yang, J.; Zhu, Q. Lead toxicity, uptake, and translocation in different rice cultivars. Plant Sci. 2003, 165, 793–802. [Google Scholar] [CrossRef]
- de Oliveira, L.M.; Gress, J.; De, J.; Rathinasabapathi, B.; Marchi, G.; Chen, Y.; Ma, L.Q. Sulfate and chromate increased each other’s uptake and translocation in As-hyperaccumulator Pteris vittata. Chemosphere 2016, 147, 36–43. [Google Scholar] [CrossRef] [PubMed] [Green Version]
- Shukla, O.P.; Dubey, S.; Rai, U.N. Preferential Accumulation of Cadmium and Chromium: Toxicity in Bacopa monnieri L. under Mixed Metal Treatments. Bull. Environ. Contam. Toxicol. 2007, 78, 252–257. [Google Scholar] [CrossRef] [PubMed]
- Tang, L.; Deng, S.; Tan, D.; Long, J.; Lei, M. Heavy metal distribution, translocation, and human health risk assessment in the soil-rice system around Dongting Lake area, China. Environ. Sci. Pollut. Res. 2019, 26, 17655–17665. [Google Scholar] [CrossRef] [PubMed]
- Gardea-Torresdey, J.L.; Peralta-Videa, J.R.; Montes, M.; De La Rosa, G.; Corral-Diaz, B. Bioaccumulation of cadmium, chromium and copper by Convolvulus arvensis L.: Impact on plant growth and uptake of nutritional elements. Bioresour. Technol. 2004, 92, 229–235. [Google Scholar] [CrossRef] [PubMed]
- Ishimaru, Y.; Bashir, K.; Nishizawa, N.K. Zn uptake and translocation in rice plants. Rice 2011, 4, 21–27. [Google Scholar] [CrossRef] [Green Version]
- Safarzadeh, S.; Ronaghi, A.; Karimian, N. Effect of cadmium toxicity on micronutrient concentration, uptake and partitioning in seven rice cultivars. Arch. Agron. Soil Sci. 2013, 59, 231–245. [Google Scholar] [CrossRef]
- Khanam, R.; Kumar, A.; Nayak, A.K.; Shahid, M.; Tripathi, R.; Vijayakumar, S.; Bhaduri, D.; Kumar, U.; Mohanty, S.; Panneerselvam, P.; et al. Metal(loid)s (As, Hg, Se, Pb and Cd) in paddy soil: Bioavailability and potential risk to human health. Sci. Total Environ. 2020, 699, 134330. [Google Scholar] [CrossRef]
- Uraguchi, S.; Fujiwara, T. Cadmium transport and tolerance in rice: Perspectives for reducing grain cadmium accumulation. Rice 2012, 5, 1–8. [Google Scholar] [CrossRef] [Green Version]
- Cui, J.L.; Zhao, Y.P.; Lu, Y.J.; Chan, T.S.; Zhang, L.L.; Tsang, D.C.W.; Li, X.D. Distribution and speciation of copper in rice (Oryza sativa L.) from mining-impacted paddy soil: Implications for copper uptake mechanisms. Environ. Int. 2019, 126, 717–726. [Google Scholar] [CrossRef] [PubMed]
- Satpathy, D.; Reddy, M.V.; Dhal, S.P. Risk assessment of heavy metals contamination in paddy soil, plants, and grains (Oryza sativa L.) at the east coast of India. Biomed Res. Int. 2014, 2014, 545473. [Google Scholar] [CrossRef] [PubMed] [Green Version]
Sample | pH | Eh | TOC | Clay | Silt | Sand | TFe |
---|---|---|---|---|---|---|---|
mV | % | ||||||
Ecuador | |||||||
Coastal provinces | 6.4 ± 0.6 | 226 ± 93 | 1.9 ± 0.6 | 49 ± 16 | 24 ± 13 | 28 ± 20 | 4.2 ± 1.0 |
range | 3.6∓7.4 | 92∓485 | 0.7∓3.2 | 23∓88 | 3∓53 | 0.9∓64 | 2.4∓7.1 |
n | 53 | 55 | 61 | 23 | 23 | 23 | 83 |
Orellana province | 5.9 ± 0.1 | n.a. | 4.4 ± 1.4 | 17 ± 14 | 17 ± 8 | 67 ± 18 | 2.7 ± 0.7 |
range | 5.8∓6.0 | 2.1∓6.1 | 6∓37 | 6∓25 | 46∓89 | 1.8∓3.6 | |
n | 8 | 8 | 6 | 6 | 6 | 8 | |
Ecuador | 6.3 ± 0.6 | 226 ± 93 | 2.2 ± 1.1 | 42 ± 20 | 22 ± 12 | 35 ± 24 | 4.1 ± 1.1 |
range | 3.6∓7.4 | 92∓485 | 0.7∓6.1 | 6∓88 | 3∓53 | 0.9∓89 | 1.8∓7.1 |
n | 61 | 55 | 69 | 29 | 29 | 29 | 91 |
Province | Cr | Zn | Pb | Cd | Cu | As | Ni |
---|---|---|---|---|---|---|---|
Tables | Total | ||||||
Guayas (n = 62) | 59.7 ± 14.3 | 84.3 ± 21.2 | 12.0 ± 7.7 | 0.23 ± 0.14 | 51.1 ± 19.1 | 4.45 ± 2.42 | 31.6 ± 13.3 |
Los Ríos (n = 21) | 47.7 ± 32.9 | 110.6 ± 26.3 | 17.8 ± 9.3 | 0.34 ± 0.14 | 86.1 ± 40.6 | 6.78 ± 4.85 | 31.1 ± 13.6 |
El Oro (n = 10) | n.a. | n.a. | 9.7 ± 2.8 | 0.30 ± 0.10 | n.a. | 3.30 ± 1.07 | n.a. |
Coastal provinces (n = 93) | 56.7 ± 21.1 | 90.9 ± 25.2 | 13.1 ± 8.1 | 0.26 ± 0.14 | 60.0 ± 30.1 | 4.86 ± 3.21 | 31.5 ± 13.3 |
Orellana (n = 8) | 14.5 ± 4.4 | 60.8 ± 17.1 | 4.3 ± 2.0 | 0.32 ± 0.14 | 29.2 ± 6.8 | 1.07 ± 0.44 | 8.5 ± 1.9 |
Ecuador (n = 102) | 53.0 ± 23.5 | 88.3 ± 26.0 | 12.4 ± 8.2 | 0.27 ± 0.14 | 57.2 ± 30.1 | 4.56 ± 3.25 | 29.5 ± 14.30 |
Bioavailable | |||||||
Guayas | 0.25 ± 0.08 | 2.21 ± 1.55 | 2.06 ± 1.19 | 0.14 ± 0.09 | 7.10 ± 4.44 | 0.15 ± 0.10 | 1.93 ± 1.08 |
(n = 62) | 0.4% | 3% | 17% | 61% | 14% | 3% | 6% |
Los Ríos | 0.17 ± 0.08 | 1.60 ± 1.00 | 0.69 ± 0.73 | 0.08 ± 0.07 | 5.27 ± 6.21 | 0.06 ± 0.05 | 0.65 ± 0.75 |
(n = 21) | 0.4% | 2% | 4% | 24% | 6% | 1% | 2% |
El Oro | 0.77 ± 0.12 | 2.01 ± 0.40 | 1.55 ± 0.86 | 0.24 ± 0.06 | 3.04 ± 0.56 | 0.20 ± 0.03 | 2.33 ± 0.55 |
(n = 3) | n.a | n.a | 16% | 80% | n.a | 6% | n.a |
Coastal provinces | 0.25 ± 0.13 | 2.05 ± 1.42 | 1.70 ± 1.23 | 0.13 ± 0.09 | 6.50 ± 4.95 | 0.131 ± 0.095 | 1.62 ± 1.14 |
(n = 86) | 0.4% | 2% | 13% | 50% | 11% | 3% | 5% |
Orellana | 0.03 ± 0.01 | 3.02 ± 2.23 | 0.61 ± 0.30 | 0.25 ± 0.18 | 3.15 ± 1.30 | 0.012 ± 0.003 | 0.21 ± 0.04 |
(n = 3) | 0.2% | 5% | 14% | 78% | 11% | 1% | 3% |
Ecuador | 0.24 ± 0.14 | 2.08 ± 1.45 | 1.66 ± 1.23 | 0.13 ± 0.10 | 6.38 ± 4.90 | 0.127 ± 0.100 | 1.58 ± 1.15 |
(n = 89) | 0.5% | 2% | 13% | 48% | 11% | 3% | 5% |
Metal | Grain | Leaf | Stem | Whole | ||||||||
---|---|---|---|---|---|---|---|---|---|---|---|---|
Average | St. dev | N | Average | St. dev | N | Average | St. dev | N | Average | St. dev | N | |
As | 0.08 | 0.03 | 14 | 0.15 | 0.09 | 8 | 0.13 | 0.06 | 9 | 0.12 | 0.06 | 31 |
Cd | 0.07 | 0.17 | 14 | 0.02 | 0.02 | 8 | 0.03 | 0.05 | 9 | 0.04 | 0.12 | 31 |
Co | 0.17 | 0.26 | 14 | 0.78 | 0.85 | 8 | 0.61 | 0.59 | 9 | 0.45 | 0.60 | 31 |
Cr | 0.50 | 0.50 | 14 | 1.98 | 1.99 | 8 | 1.12 | 0.80 | 9 | 1.06 | 1.25 | 31 |
Cu | 3.76 | 1.30 | 14 | 4.23 | 1.66 | 8 | 3.98 | 4.43 | 9 | 3.95 | 2.58 | 31 |
Ni | 0.92 | 0.58 | 14 | 0.77 | 0.37 | 8 | 0.86 | 0.90 | 9 | 0.87 | 0.63 | 31 |
Pb | 0.19 | 0.20 | 14 | 0.12 | 0.05 | 8 | 0.07 | 0.04 | 9 | 0.14 | 0.14 | 31 |
Zn | 24.08 | 7.30 | 14 | 18.78 | 8.72 | 8 | 33.55 | 19.02 | 9 | 25.46 | 13.03 | 31 |
BCF on Melich. | As * | Cd * | Cr * | Cu * | Ni * | Pb * | Zn * |
---|---|---|---|---|---|---|---|
Stem | 1.6 ± 1.3 (8) | 0.27 ± 0.57 (9) | 5.3 ± 4.4 (8) | 0.61 ± 0.94 (9) | 0.56 ± 0.61 (9) | 0.03 ± 0.02 (9) | 18.7 ± 16.8 (9) |
Leaf | 1.7 ± 1.1 (8) | 0.13 ± 0.07 (8) | 8.0 ± 6.6 (8) | 0.58 ± 0.18 (8) | 0.49 ± 0.12 (8) | 0.05 ± 0.02 (8) | 9.2 ± 5.7 (8) |
Grain | 0.76 ± 0.44 (11) | 0.18 ± 0.10 (11) | 2.21 ± 2.35 (13) | 0.55 ± 0.34 (13) | 0.54 ± 0.45 (13) | 0.08 ± 0.08 (13) | 10.5 ± 8.3 (13) |
Plant | 1.31 ± 1.00 (min = 0.12; max = 4.64) | 0.20 ± 0.30 (min = 0.05; max = 1.64) | 4.52 ± 4.93 (min = 0.46; max = 22.0) | 0.59 ± 0.55 (min = 0.17; max = 3.10) | 0.54 ± 0.44 (min = 0.12; max = 2.14) | 0.06 ± 0.06 (min = 0.01; max = 0.27) | 12.78 ± 11.59 (min = 2.44; max = 55.8) |
BCF on total | |||||||
Stem | 0.04 ± 0.03 | 0.31 ± 0.32 | 0.04 ± 0.03 | 0.09 ± 0.11 | 0.05 ± 0.04 | 0.01 ± 0.01 | 0.37 ± 0.27 |
Leaf | 0.05 ± 0.06 | 0.09 ± 0.12 | 0.09 ± 0.09 | 0.12 ± 0.11 | 0.07 ± 0.07 | 0.02 ± 0.01 | 0.23 ± 0.09 |
Grain | 0.03 ± 0.03 | 0.18 ± 0.12 | 0.06 ± 0.04 | 0.07 ± 0.05 | 0.05 ± 0.04 | 0.03 ± 0.01 | 0.29 ± 0.15 |
Plant | 0.04 ± 0.04 (min ≤ 0.01; max = 0.20) | 0.23 ± 0.22 (min = 0.01; max = 1.23) | 0.05 ± 0.07 (min < 0.01; max = 0.31) | 0.09 ± 0.09 (min = 0.10; max = 0.52) | 0.06 ± 0.05 (min < 0.01; max = 0.26) | 0.02 ± 0.02 (min < 0.01; max = 0.10) | 0.30 ± 0.19 (min < 0.09; max = 1.18) |
Singh et al. [57] | 0.011 | 0.012 | - | 0.002 | - | 0.028 | - |
Tariq and Rashid [58] | - | 0.024 | 0.185 | - | 0.539 | 0.043 | - |
Luo et al. [59] | - | 0.001 | 0.059 | 0.012 | 0.004 | 0.001 | - |
Cao et al. [60] | - | - | - | - | - | 0.002 | |
Du et al. [43] | 7.26 ± 4.86 | 5.35 ± 3.89 | 0.285 ± 0.156 | 0.457 ± 0.179 | 0.234 ± 0.134 | 0.516 ± 0.308 | 0.504 ± 0.162 |
Xie et al. [61] | 0.056 ± 0.0046 | 0.459 ± 0.010 | 0.015 ± 0.0005 | 0.090 ± 0.0057 | - | 0.012 ± 0.0004 | - |
Li et al. [33] | 0.042 | 0.171 | 0.688 | 0.287 | - | 0.029 | 0.107 |
Hseu et al. [62]–on bioavailable fraction | Ni-grain = 2.92 × Ni-soil 0.08 ** |
Publisher’s Note: MDPI stays neutral with regard to jurisdictional claims in published maps and institutional affiliations. |
© 2021 by the authors. Licensee MDPI, Basel, Switzerland. This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution (CC BY) license (https://creativecommons.org/licenses/by/4.0/).
Share and Cite
Atiaga, O.; Ruales, J.; Nunes, L.M.; Otero, X.L. Toxic Elements in Soil and Rice in Ecuador. Agronomy 2021, 11, 1594. https://doi.org/10.3390/agronomy11081594
Atiaga O, Ruales J, Nunes LM, Otero XL. Toxic Elements in Soil and Rice in Ecuador. Agronomy. 2021; 11(8):1594. https://doi.org/10.3390/agronomy11081594
Chicago/Turabian StyleAtiaga, Oliva, Jenny Ruales, Luís Miguel Nunes, and Xosé Luis Otero. 2021. "Toxic Elements in Soil and Rice in Ecuador" Agronomy 11, no. 8: 1594. https://doi.org/10.3390/agronomy11081594