Heavy metal contamination in agricultural areas in Tocantins state

Authors

• Michele Ribeiro Ramos Professora Universidade Estadual do Tocantins
• Mônica Ferreira De Abreu Pesquisadora Instituto Agronômico de Campinas
• João Vitor De Medeiros Guizzo Graduando Universidade Estadual do Tocantins
• Divonzil Gonçalves Cordeiro Pesquisador na Embrapa Pesca e Aquicultura e Sistema de produção
• Phillipe Farias Ferreira Professor Instituto Federal do Tocantins - IFTO

DOI:

https://doi.org/10.17058/tecnolog.v24i2.14845

Keywords:

CONAMA 420, Referência de qualidade, Impacto ambiental, Legislação.

Abstract

The present work consisted in the collection of soils samples for the analysis and description of heavy metals values in agricultural areas of some municipalities in the state of Tocantins. The purpose is to make comparisons with the Reference Values established for the states of São Paulo (SP) and Minas Gerais (MG), once, there is no reference values do exist for the state of Tocantins. Soil samples were collected from 27 agricultural areas, and submitted to the EPA3051 digestion method, proposed by the Environmental Protection Agency (EPA). The soils samples showed different levels of heavy metal concentration, with arsenic (As), mercury (Hg) and selenium (Se) being more constant. There has been no levels of heavy metals close to the Agricultural Research Values, only a few elements exceeded the limit of Prevention Values and the Quality Reference Values (QRV) proposed for the states of SP, as well as for the QRV established for the areas in the state of MG. These concentrations, however, pose no risk for soils contamination.