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Wearing appropriate personal protective equipment during the application of pesticides is one method of reducing dermal exposure to pesticides. Thus, the aim of this research is to develop personal protective clothing (PPC) coated with gum rosin and investigate the efficiency of its level of protection against chlorpyrifos and cypermethrin. Comparison of the protection efficiency of each PPC with Tychem® C coveralls was also investigated. Five commercially available cotton fabrics were chosen for tailoring the PPC, and then, the PPC was coated with a gum rosin finish to provide water repellence. The efficiency of the level of protection of the gum rosin-coated PPC against insecticides was tested in a laboratory (closed chamber). The remarkable findings were that the % protection efficiencies for all the PPC, with the exception of one, were not significantly different to those for Tychem® C coveralls. The protection efficiencies ranged from 99.85% to 99.97% against chlorpyrifos and 99.11% to 99.89% against cypermethrin. Therefore, our results suggest that gum rosin-coated clothing provided satisfactory levels of protection against insecticides and could be considered as suitable protective clothing for pesticide applicators. Choice of an appropriate fabric for coating with gum rosin also needs to be considered. A further study in field conditions is warranted to confirm the protection efficiency in a working environment.

Microstructure and phase development during the thermal decomposition of sol–gel precursor coatings of PbZr0.53Ti0.47O3 on platinized silicon substrates have been investigated for a triol sol–gel route. The single‐layer, 0.4 μm PZT films were heated from below the substrate, over the temperature range 350–600°C, using a calibrated hot plate. The first crystalline phase to appear was a PbPt3 intermetallic phase at the Pt/PZT interface. Although perovskite PZT formed at ca. 500°C, heating at higher temperatures, for example 550°C for 30 min, was required to develop ferroelectric hysteresis loops. However, the rather low value of remanent polarization, Pr= 11 μC·cm−2, was consistent with incomplete crystallization at 550°C. The values of remanent polarization increased with increasing processing temperatures, reaching 21 μC·cm−2 for samples heated at 600°C, with a corresponding Ec value of 57 kV·cm−1. Distinctive spherical precipitates up to ca. 50 nm in size have been identified by TEM in the lower portions of otherwise amorphous coatings, after heating at around 350–400°C. Although their precise composition could not be identified, they were mostly Pb‐rich, and it is speculated that they form due to reduction of some of the lead(II) acetate starting reagent, to atomic Pb during the early stages of thermal decomposition of the organic components of the gel; it is possible that subsequent reactions occur to form lead oxides or carbonates. High levels of porosity were present in many of the fully crystallized films. The possible reasons for this are discussed.

Farmers are at a high risk of inhalation exposure when handling pesticides. Thai farmers usually protect themselves against pesticide exposure by wearing commercial respiratory protective equipment (RPE) available from rural community markets. However, scientific data regarding the pesticide filtration efficiency of RPE commonly worn by farmers is limited. Thus, this study aimed to investigate the efficiency of insecticide filtration of various RPE commonly worn by farmers in Thailand. The half facepiece respirator was used as a control to compare the results with other RPE. Ten types of RPE were selected for testing. The filtration efficiency of each RPE against insecticides was tested in a laboratory. The remarkable findings were that a surgical mask demonstrated the least filtration efficiency of all tested insecticides, with a range of 25.7–61.5%. The RPE available in rural markets of Thailand had a filtration efficiency within a range of 64.9–95.4%, whereas a half facepiece respirator was the most efficient in filtering insecticides, with a range of 96.5–98.9%. Therefore, our results suggest that the RPE most frequently worn by farmers may not provide adequate protection when compared with the respirator. However, considerations around RPE use in low-and middle-income countries and tropical climate conditions should be based on pesticide toxicity and practical use, ensuring balance between the risks from pesticide exposure and acceptance of PPE use.