
THE PROJECT REMOVAS
Removing Arsenic from rice with microalgae
Rice is the main staple food source for billions of people worldwide, and As tends to accumulate in higher concentrations in this grain crop, more than in other grain crops, increasing the human health risk. Arsenic is one of the main toxic element found in the environment, as a result of natural geogenic and anthropic sources. Because its potential risk to the ecosystem and to human health the United States Environmental Protection Agency (USEPA) classifies inorganic As as a group A carcinogen and the Agency for Toxic Substances and Disease Registry (ATSDR) ranked As as number one in its 2019 Substance Priority List. High As concentrations in rice grain is a consequence of As bioavailability in soil and speciation under conditions in which rice is cultivated and own intrinsic ecophysiological behaviour of this species. This can be a result from soil reducing conditions by flooding as it from the use of irrigation waters with high As levels. Therefore, it is a major research goal to issue sustainable production strategies that create conditions for a decrease uptake of As in paddy fields and consequently decrease As accumulation in the rice grain. The growth of algae in rice fields has been considered a natural fertilization process, as decomposition of algae adds nitrogen and other nutrients to the paddy soil. Moreover, microalgae produce oxygen during its phototrophic growth, which could create conditions that allows shifts in the paddy water redox potential and pH, thus promoting oxidation of As(III) to As(V) and further methylation, decreasing the bioavailability of As for uptake. The purpose of this project is to explore the possibility of integrating microalgae cultures into the rice paddy fields farming system towards decreasing the bioavailability of As for uptake, without compromising rice yields and the agroecosystem. Moreover, the project will also explore the use of paddy fields microalgae as potential secondary sources of income for rice producers (e.g. production of bioenergy) and creating new differentiated products to the rice miller’s portfolio. The holistic value chain approach of this proposal, is in line with the new European Green Deal policy framework linked with the UN 17 Sustainable Development Goals for 2030, to promote a resource-efficient and competitive economy while guarantying the health and well-being of citizens from environment-related risks and impacts, covering the “farm to fork” food value chain.
OBJECTIVES AND THEMATIC LINES ADDRESSED
The objective is to evaluate the influence that microalgae produces in rice paddy redox conditions, to decrease the level of As in rice grains, and follow up the food value chain, finding an added value for the microalgae biomass and diversify the rice millers portfolio. Thematic line: Tropical Agriculture & Agri-Food Value Chains addressing the topic “Tropical agro-food systems”. The idea can be easily implemented on tropics as well as in Portugal. An agro-food system combining a microalgae and a food crop for a synergism on As uptake will be fundamental on tropical countries, struggling with high levels of As in irrigation water, such as Bangladesh, but it will also be useful in Iberian peninsula where some regions produce rice with As levels too close to the limits set up by EU legislation. The idea came out from a previous study dealing with microalgae and other studies about As behaviour in soil-rice system in different paddy soils from Portugal and Spain. LEAF is the right place to implement such a knowledge cross-cutting project, since it gathers scientific experts with large experience working with these issues, from all the LEAF research groups.

THE REMOVAS TEAM
PATRICIA E. D. VIDIGAL
PI
Abiotic Stress; Antioxidative system; Soil rehabilitation; Crop Production

ISABEL MARIA NUNES DE SOUSA
Co-PI
Food Rheology; Sustainable Functional Foods product development

ANTÓNIO GUERREIRO DE BRITO
resource recovery and biofilms - bioenergy, phosphorus, environmental engineering, water management and planning
agbrito@isa.ulisboa.pt
https://orcid.org/0000-0003-1356-3

CRISTIANE OTTONI
Biotechnology, Fungi, Nanotechnology, Microbial Fuel Cell, Enzymes, Trametes versicolor, Wastewater treatment
cristiane.ottoni@unesp.br
https://orcid.org/0000-0003-4069-509X

DAVID FANGUEIRO
Animal manure treatment, Agronomic valorization, Environmetal impact, Gaseous emissions

EMÍLIA SILVA
pesticides, aquatic ecotoxicology, environmental contamination, environmental risk assessment
emiliasilva@isa.ulisboa.pt
https://orcid.org/0000-0002-7498-8926

ERIKA S. SANTOS
Environmental rehabilitation, Biogeochemistry, Technosols, Phytostabilisation/Phytoremediation, Soil-plant system, Contaminated/degraded areas
erikasantos@isa.ulisboa.pt
https://orcid.org/0000-0002-3664-839X

MARIA DA GLORIA ESQUIVEL
Photobioreactors; Nannochloropsis; Chlorella Sorokiniana; Ectothermy; Heat Tolerance; Acclimatization
gesquivel@isa.ulisboa.pt
https://orcid.org/0000-0003-1772-0015

Mª JOSÉ CEREJEIRA
pesticides, aquatic ecotoxicology, environmental contamination, environmental risk assessment

Mª LUÍSA LOURO MARTINS
edible plants biochemistry, bioactive compound, chemical contaminants, abiotic stress, antiox
luisalouro@isa.ulisboa.pt
https://orcid.org/0000-0002-9486-6053

Mª MANUELA ABREU
Phytoremediation, mines, metals, trace elements
manuelaabreu@isa.ulisboa.pt
https://orcid.org/0000-0002-6650-1161

MIGUEL MOURATO
Heavy metals, oxidative stress, antioxidative enzymes
mmourato@isa.ulisboa.pt
https://orcid.org/0000-0003-4843-1064

SERRA PAIXÃO
PhD Student
Serra is an aquaculture engineer. She holds a master`s degree in water quality & chemistry as well as an MBA in international marketing & foreign trade. After working for several years as an engineer with a focus on RAS design and environmentally sustainable aquaculture practices, she started to pursue a career in marketing within Ireland, Netherlands and Portugal. She is currently working as a Project Manager at a non-for-profit business association in off-grid solar sector and is a Ph.D. student at the Instituto Superior de Agronomia, University of Lisbon - LEAF Research Center.

PROJECT OUTPUTS

FUNDING AND OUR RESEARCH CENTER
https://www.isa.ulisboa.pt/en/leaf/presentation
Funded by national funds through FCT in the scope of the project LEAF Research Unit Ref. UIDB/04129/2020
