Effects of herbicide spraying period and volume on the safety of tractor drivers spraying herbicides on sugarcane (Saccharum spp.) crop

摘要

This work aimed to evaluate the effects of herbicide application period and volume on the safety of tractor drivers applying herbicide on sugar cane crops using a boom sprayer set and the efficiency of individual protective equipment (IPE), and of a cabin coupled to the tractor. Dermal exposure under thirteen working conditions was evaluated and statistically analyzed in a randomized complete design and a 3 x 2 x 2 + 1 factorial scheme. Factor A constituted the exposure conditions: 1) potential dermal exposure (PDE) – without safety measures; 2) tractor cabin exposure (Cabin) and 3) exposure with clothes on. Factor B constituted volume applications: 1) 200 L ha-1 and 2) 100 L ha-1 and factor C constituted the periods of application: 1) day and 2) night. As control, the tractor driver's PDE was evaluated by applying 300 L ha-1 during the day. Dermal exposure (DE) to the herbicides utilized under these working conditions was calculated by substituted data of the SEs evaluated to the cation Cu+2 added to the mixture, as a tracer. The sprayer was a PJ 600 model, with 12 m long bar and 24 Teejet TT 110 04 or TT 110 02 nozzles. The thirteen working conditions evaluated were classified as safe to the tractor driver applying the herbicides glyphosate (48% ia), MSMA (48%), diuron (46.8%) + hexazinone (13.2%), clomazone (50%), sulfentrazone (50%), ametryne (50%), diuron (50%), isoxaflutole (75%), metribuzin (48%), 2,4 D (80.6%), ametryne (30%) + clomazone (20%), ametryne (73.25%) + trifloxysulfuron (1.85%), tebuthiuron (80 %) and as not safe, applying the atrazine herbicide (50%) during the day, and 100 L ha-1. Night applications and reduced application volumes provided safer work conditions , except for atrazine. IPE efficiency for the 300 L ha-1 applications was around 69.5% and 89.3% and 76.4% to 83.3% for the tractor cabin, compared to the reduced volumes of 100 and 200 L ha-1 .