Samples field workers

In addition, the use of field fortification samples measures the carefulness factor of the Field Scientist during the field research and allows a Study Director/Manager or distant observer to obtain a quality control estimate on the field portion of the study. For this reason, the field fortification samples are usually meant to be different from laboratory procedural fortifications and are meant to be prepared under field conditions, which are considerably more rigorous than are controlled laboratory conditions. For example, environmental factors such as heat, humidity, wind, human stress, and other human factors such as fatigue to the Field Scientist are an integral part of any field worker exposure/re-entry study. Field fortifications made to matrices under these conditions will test and readily demonstrate the ability of the Field Scientist to perform such a difficult study under trying circumstances. 

Low levels of 3,5,6-TCP were also observed in pre-exposure urine from most of the field workers. These 3,5,6-TCP levels were subtracted from urine field recovery samples and were used to correct levels of 3,5,6-TCP found in the post-exposure urine samples from these same workers. This procedure was necessary to calculate the amount of 3,5,6-TCP in the urine that was attributable to the exposure period. 

The industry task forces (ARTF, ORETF, and others) are generating model protocols, efficient and accurate methods of sample collection, and analytical methods of appropriate detectability for use in field-worker exposure studies. Subsequently, the task forces are conducting field studies that will generate data for inclusion in several generic databases. It is understood that the databases will be the property of the member companies who have financed the work of the task forces. It is hoped, however, that the task forces will see fit to publish their protocols, methods, study designs, and other useful information in a volume like this one so that other scientists working in this discipline may access the information. 

Before beginning the analysis of FMs at low concentrations, the laboratory should analyze several laboratory blank samples to assess the degree to which the laboratory is contaminated. With every set of samples analyzed, the laboratory should also analyze a laboratory and field blank sample. Laboratory workers should be advised to be aware of their personal use of fragrance-enhanced consumer products and the potential for laboratory contamination. 

Twenty-five children selected at random received aerosol treatment with RP 6000 vitamin A units per 2 weeks over 3 months being provided. Twenty-five further children served as controls receiving a placebo also aerosol delivered. The aerosol was administered through the mouth during breath inhalation with an adapter. No adverse effects or reactions were observed during inhalation and the children complied well with the treatment. Trained field workers performed the inhalation trials and blood sampling. In the study and control group. Heparin blood samples were collected before and at completion of the study for measurements of vitamin A, RBP, and TTR concentrations. 

In a letter to Nature, Dr. L. Scott Mills, director of the laboratory that analyzed the samples, stated that the protocol used for the lynx survey had been validated with appropriate controls in two labs. His testing protocol had been peer reviewed and published. He said, For a field worker to arbitrarily decide to test the lab by labeling a hair from elsewhere as if it were a field-collected sample corrupts the integrity of the data and does not constitute a blind control. 7... 

Peoples, A. Love, R. Cholinesterase activity in blood samples collected from field workers and nonfield workers in California. Toxicology and Applied Pharmacology, 1978, 45,... 

Dialifor. The organophosphate pesticide, dialifor, is registered for use in control of insects on such crops as grapes and citrus. Significant exposure to this toxic compound is feasible for pesticide formulators, and applicators, and for field workers who harvest the crops. We have applied reverse phase HPLC for analysis of this compound on wipe (filter) samples taken in the field. For this analysis, the following conditions and parameters are employed ... 

Air sampling for occupational exposure to pesticides normally consists of measurement of pesticide concentrations in the worker s breathing zone, with a portable air-sampling pump and a sampling train which includes some type of collection device. The latter device, or sampling media, selected are based on the physical and chemical properties of the compound to be measured. Field workers may be exposed to chemical vapors, solid particulates or water-based aerosols. Examples of sampling media include membrane filters, sorbent tubes, polyurethane foam and charcoal. A discussion of pesticide exposure provides a useful review of methods for respiratory exposure measurement (Nigg etal, 1990). 

The electrolytes Na", and Cl are second only to glucose in being the most frequently run hospital tests. Many clinical chemistry analyzers now contain an ISE module for electrolyte analysis. Most commonly the module will consist of a Na -glass electrode, a valinomycin/PVC electrode, a Ag/AgCl pellet or a quaternary ammonium ion/PVC electrode and a reference electrode. A selective electrode for the bicarbonate ion continues to elude workers in the field. An indirect measurement of HCOf must be made. The sample is usually reacted with acid to evolve carbon dioxide gas which is measured with a traditional Severinghaus type CO2 electrode. Alternatively, the sample is treated with base to convert HCO to CO3 and a carbonate ion-selective electrode is used In this manner, the complete primary electrolyte profile is obtained electrochemically. 

The purpose of this article is to present a detailed description of the current field methods for collection of samples while measuring exposure of pesticides to farm workers. These current field methods encompass detailed descriptions of the methods for measuring respiratory and also dermal exposure for workers who handle the pesticide products directly (mixer-loaders and applicators) and for re-entry workers who are exposed to pesticide dislodgeable residues when re-entering treated crops. 

The field laboratory set up by the field research group is a key element to completing successful worker exposure/re-entry research. The field laboratory may be set up in close proximity to the treated field, but should be located at a reasonable distance from the treated area to avoid cross-contamination of field samples and field controls. 

Portable weather stations are useful to have available at the field laboratory for acquiring weather data during the course of the worker exposure/re-entry study. There are a variety of portable weather stations available from a variety of suppliers. Weather data to be collected are rainfall, wind direction, wind speed, air temperature, and relative humidity. These electronic weather stations will record the necessary weather parameters on a routine basis. The data are stored and can be transferred to a laptop computer or disk as desired by the Field Scientist. Such portable electronic weather stations are useful during the course of the dislodgeable residue portion of a worker re-entry study when dislodgeable residue samples are taken from remote test sites over the course of a 30-day period. 

The test substance may be acquired in a number of ways. One common method is to purchase the product from a chemical dealer. This method of acquiring the test substance for a worker exposure or re-entry study allows one to proceed rapidly with the execution of the field portion of the study without the serious delays encountered while waiting for a test substance to be manufactured, assayed, and shipped to the site. Although having a test substance formulation which has been assayed under GLP standards and for which a certificate of analysis has been shipped to the test site is desirable, there are several instances when this is not practical. For example, one may encounter a worker exposure study where the pesticide to be evaluated is sold only in mini-bulk or even large bulk quantities holding as much as 2000 gal. In this case, duplicate 5-10-g or 5-10-mL retainer samples should be taken from the bulk or mini-bulk tanks for assay after the worker exposure study is in progress. 

Field fortification of worker exposure matrix samples (a) Purpose for having field fortification samples... 

Field fortification (commonly referred to as field spiking) is the procedure used to prepare study sample matrices to which have been added a known amount of the active ingredient of the test product. The purpose for having field fortification samples available in a worker exposure study is to provide some idea of what happens to the test chemical under the exact environmental field conditions which the worker experiences and to determine the field storage stability of the test substance on or in the field matrix materials. Field fortifications do not serve the purpose of making precise decisions about the chemical, which can better be tested in a controlled laboratory environment. The researcher should not assume that a field fortification sample by its nature provides 100% recovery of the active ingredient at all times. For example, a field fortification sample by its very nature may be prone to cross-contamination of the sample from environmental contaminants expected or not expected to be present at the field site. 

Such field-fortified matrix samples are absolutely necessary as a part of any worker exposure or re-entry study in order for the behavior of the active ingredient to be... 

The collection of air samples using air tubes and/or filters is of value during the course of the field research when performing SDDBM studies. The air tube/air filter data can be used to estimate the portion of the total body burden, which originates from respiratory exposure to the active ingredient. Of course, if an organic vapor respirator is used by the worker as a matter of course, the respiratory exposure component should be backed out of the final exposure calculation. 

During refueling, the respective concentrations were 1.64, 1.33, 0.78, 0.19, and 6.34 mBq/m3 (44.3, 35.9, 21,5.1, and 171 fCi/m3). The derived air concentration recommended by the ICRP for occupational exposure is 80.0 mBq/m3 (2,200 fCi/m3). In 1997, the French radiation protection office conducted monitoring (24-hour urine analysis/whole body activity measurements) of workers in the non-nuclear energy field (i.e., nuclear medicine, research laboratories, and non-nuclear industries) to ascertain the occupational intake of radionuclides (De Vathaire et al. 1998). 241Am was not detected in samples from any of the 37 workers who worked with the isotope. 

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