Alan P. Nielsen

A Test Method for the Evaluation of Protective Glove Materials Used in Agricultural Pesticide Operations

The ASTM Standard Test Method for Resistance of Protective Clothing Materials to Permeation by Liquids and Gases (F 739-85) and the recommended permeation cell have been modified to permit the testing of protective clothing materials for permeation by the low volatility, low water solubility active ingredients present in many pesticide formulations. The modification makes use of solid collection medium, a thin (0.02-in. thick) sheet of silicone rubber, to collect permeants. Those compounds permeating the protective material can then be desorbed into an appropriate solvent and analyzed using conventional methods and instruments. A series of permeation tests have been conducted using samples of 10 common, commercially available protective glove materials and the modified cell. Permeation of the active ingredient as well as carrier solvent components of several concentrated pesticide formulations containing low volatility, low water solubility active ingredients and aromatic hydrocarbon carrier solvents has been monitored. The relative breakthrough and the total mass of material permeating the glove materials appears to be strongly related to the concentration of the aromatic carrier solvent present in the formulations studied to date. The collection method was found to be less useful for monitoring the permeation of active ingredients, which have reasonably high water solubilities. The results obtained by using this method with samples of protective glove materials challenged by several concentrated pesticide formulations are described. For these formulations containing xylene boiling range aromatic solvents, gloves made of nitrile rubber, butyl rubber, and Silver Shield were most resistant to permeation; natural rubber and polyethylene glove materials were least resistant.

PERMEATION RESISTANCE OF GLOVE MATERIALS TO AGRICULTURAL PESTICIDES

The toxicities of many agricultural pesticides require that hand protection be used by persons who mix, load, and apply these products, as specified on the label and material safety data sheet. Selection of gloves for formulations that contain organic solvents is particularly problematic because a solvent that permeates the glove can carry with it the active ingredient of the pesticide formulation. With a test method that measures the simultaneous permeation of the carrier solvent(s) and active ingredient(s), in particular those active ingredients that have low solubility in water and low volatility, over 100 permeation tests (in triplicate) with approximately 20 pesticide formulations were conducted with 13 different glove materials. These results are summarized and generalizations are presented within the perspective of the large base of permeation data for neat chemicals and another large permeation study with pesticides. Key among the findings is that the carrier solvent generally permeates first and at a much higher rate than the active ingredient. Furthermore, the permeation behavior of formulations containing solvents generally mirrored that of neat carrier solvents alone. Thus, insight into the selection of the most appropriate glove material for a given pesticide formulation can be gained from permeation data for neat chemicals. For the types of solvents that may be present in pesticide formulations, preferred materials include nitrile rubber, butyl rubber, and plastic film laminates. Natural rubber and polyvinyl chloride materials generally are not recommended.

The United States Environmental Protection Agency, Health Canada, and National Agricultural Chemicals Association Pesticide Handlers Exposure Database

Abstract The Pesticide Handlers Exposure Database has been developed to provide generic pesticide worker (i.e., applicator) exposure estimates. The dermal and inhalation exposure estimates generated by the system are based on actual field monitoring data, which are reported genetically (i.e., not chemical specific). The Pesticide Handlers Exposure Database provides a much larger number of observations than are available from a single exposure study when conducting exposure and risk assessments. The exposure data in the system have been reviewed for scientific integrity and are graded based on analytical quality assurance. The U.S. Environmental Protection Agency is currently using the Pesticide Handlers Exposure Database for the pesticide registration/reregistration process. The major limitation of the system is the insufficient amount of data. To increase the utility of the database, the Pesticide Handlers Exposure Database Task Force is currently updating the system with an additional 50 exposure studie...

Protective clothing and the agricultural worker

The purpose of this paper is to provide an overview of the role of protective clothing in hazard reduction for pesticide applicators and mixer/loaders. Research and other activities of the Office of Pesticide Programs, U.S. Environmental Protection Agency, relating to worker exposure and protective clothing are discussed, including field and laboratory studies. The goal of the program, to identify personal protective equipment that will be effective from performance and worker acceptability standpoints, is also discussed.

The Pesticide Handlers Exposure Database (PHED): Regulatory Overview

The Pesticide Handlers Exposure Database (PHED) has been developed by the PHED Task Force in response to a NACA committee proposal that was originally presented at a 1984 American Chemical Society meeting (Hackathorn and Eberhart 1985) and further discussed in Eberhart et al., (1988). The proposal was to develop a publicly available generic database for estimating applicator exposure. The Task Force consists of representatives from Health Canada, the U.S. Environmental Protection Agency (U.S. EPA), and the National Agricultural Chemicals Association (NACA). PHED contains exposure and related data for a large number of workers engaged in mixing/loading and applying pesticide.