In present times, the Brazil is in the middle of the largest pesticide consumers worldwide, which demands proper control of environmental contamination. This study evaluated herbicides, acaricide, insecticides and fungicides in water and sediment carried-out from Lageado Tacongava hydrographic basin, Rio Grande do Sul, Brazil. For analysis, a QuEChERS (Quick, Easy, Cheap, Effective, Rugged and Safe), and/or SPE (Solid-Phase Extraction) using HPLC (High Performance Liquid Chromatography) with MS (Mass Detector) was optimized. As result, the Linearity R2 > 0.99; Recuperation between 78 a 117%; and RSD < 20% for the 70 compounds simultaneously analyzed. The Acetamiprid, Azoxystrobin, Bendiocarb, Fenamidone, metribuzin, Pendimethalin, pyridaben, Thiophanate-methyl and Truflumizole found in water, and Acetamiprid, Azoxystrobin, Bendiocarb, boscalid and thiophanate-methyl in sediment, at concentrations from 0.1 µg kg-1 to 39.6 µg kg-1. Standard of pesticide residues in water and sediment studies are needed to evaluate such contamination. Regional samplings standard, as was done here, will be useful in a future water resources contamination mapping.

O objetivo deste trabalho foi avaliar a eficiência de dois planos de amostragem para análise de fumonisinas (B1+B2) em 11 lotes de milho. Empregaram-se o plano de amostragem manual em grãos inteiros, através do calador graneleiro e o plano de Amostragem Automático em Fluxo Contínuo em grãos moídos (AAFC). Para a comparação dos dois planos de amostragem, foram utilizadas duas medidas de dispersão: a variância e o coeficiente de variação. Em cada plano de amostragem, foram determinadas as variâncias associadas às três etapas do procedimento de detecção das fumonisinas (amostragem, preparação da amostra e análise) e os coeficientes de variação total. A correlação entre as médias de concentrações de fumonisinas e as variâncias de cada etapa do procedimento de detecção foi avaliada para cada plano amostral através da análise de regressão. Na AAFC de milho moído para análise de fumonisinas, obtiveram-se resultados inferiores (P<0,01) de variância na etapa de amostragem (0,0226mg kg-1)², assim como no coeficiente de variação total (6,37%), quando comparados com a variância da amostragem manual (0,0685mg kg-1)² e coeficiente de variação total do plano de amostragem manual em grãos inteiros (8,94%), apresentando, portanto, maior eficiência na detecção de fumonisinas em milho.

The aim of this research was to evaluate the efficiency of two sampling plans for fumonisins (B1+B2) analysis in 11 lots of maize. For sample collection the two systems used were a manual system in whole grains, using sampling spear, and an automatic system in milled grains, using the continuous flow sampling system (CFSS). For comparison purpose, two dispersion measurements were used: variance and coefficient of variation. For each sampling plan the variance associated to the three steps of fumonisins quantification (sampling, sample preparation, and analysis), and the total coefficient of variation were determined. The correlation between the average fumonisins concentration and the variances for each phase of the detection procedure was evaluated for each sampling plan using analysis of regression. At the automatic sampling plan in milled grains for fumonisins analysis in maize both sampling variance (0.0226mg kg-1)² and total coefficient of variation (6.37%) were lower (P<0.01) than in the manual sampling plan in whole grains whit (0.0685mg kg-1)² of variance and 8.94% of coefficient of variation, showing so better efficiency for fumonisin detection on maize.