Neck exposure

In the past, 4 x 4 in cotton patches (gauze or cellulose) have been used to estimate face and neck exposure. The patches are designed and manufactured as described above and are pinned or attached with Velcro to the back and front of a hat or protective headgear of the worker. When the exposure period is complete, the patches are removed, and... 

Use of hand washes, face wipes, or head patches to measure hand, face, and neck exposure... 

The personal samples on the chest and back allow an estimate of pesticide exposure based on the standard technique of extrapolating from patch to total body region. The standard method only considers unprotected regions of the body to be exposed. In this case, only the head and neck of the workers are unprotected, and in four of six cases face shields were worn. Thus, beyond a comparison of head and neck exposure for workers 1 and 2, it is not clear how the patch technique could be applied in this study. Later in this paper the patch data will be employed to make this comparison. These... 

As methods of exposure estimation, neither the fluorescent tracer technique nor the patch technique have been validated. Nevertheless, it would be encouraging if a comparison of estimates by the two methods yielded roughly equivalent results. The only body region which can be reasonably compared is the head, as the patch method assumes no clothing penetration, and no hand wash was conducted in this study. Furthermore, four of the six workers must be excluded, as they wore face shields. Thus, the only comparison available is the head and neck exposure of workers 1 and 2. These data are presented in Table IX. Following the protocol outlined by Durham and Wolfe ( ) and Davis ( ), the amount of diazinon recovered from the dermal monitor on the chests of the two workers is employed to calculate exposure to the face and front of neck. A similar patch on the back allows calculation of exposure to the back of the neck. 

The composition of the outer pad was consistent with most commercially available coveralls. As in the case of the head, face, and neck exposures, values were extrapolated to estimate exposures of the total surface area. 

The toxicity of chloronaphthalenes requires that special attention and caution be used during their manufacture and use acne is the most common result of excessive skin exposure to them and the most frequendy affected areas are the face and neck (16). Liver damage has occurred in workers who have been exposed repeatedly to vapors, particulady to those of penta- and hexachloronaphthalene [1335-87-1] (17,18). Uses for the chlorinated naphthalenes include solvents, gauge and instmment duids, capacitor impregnants, components in electric insulating compounds, and electroplating stop-off compounds. 

The apparatus consists of a 1-1. three-necked flask equipped with a condenser, a dropping funnel, and a stirrer terminating in a stiff, crescent-shaped Teflon polytetrafluoroethylene paddle. The stirrer motor must have good torque (Note 1). The assembled apparatus, which is protected from moisture by means of drying tubes in the condenser and funnel, is preferably predried. About 216-224 g. (1.62-1.68 moles) of powdered anhydrous aluminum chloride is added to the apparatus with as little exposure to the moisture of the air as possible (Note 2). While... 

Industrial environments expose individuals to a plethora of airborne chemical compounds in the form of vapors, aerosols, or biphasic mixtures of both. These atmospheric contaminants primarily interface with two body surfaces the respiratory tract and the skin. Between these two routes of systemic exposure to airborne chemicals (inhalation and transdermal absorption) the respiratory tract has the larger surface area and a much greater percentage of this surface exposed to the ambient environment. Or dinary work clothing generally restricts skin exposures to the arms, neck, and head, and special protective clothing ensembles further limit or totally eliminate skin exposures, but breathing exposes much of the airway to contaminants. 

If the substance is unaffected by exposure to the air, it may be weighed on a watch glass, or in a disposable plastic container. The weighing funnel (Fig. 3.8) is very useful, particularly when the solid is to be transferred to a flask having weighed the solid into the scoop-shaped end which is flattened so that it will stand on the balance pan, the narrow end is inserted into the neck of the flask and the solid washed into the flask with a stream of water from a wash bottle. 

Many of the non-aqueous solvents used must be protected from exposure to the air, and titrations with such materials must be conducted in a closed vessel such as a three- or four-necked flask. It must also be noted that organic solvents have much greater coefficients of thermal expansion than has water, and every effort must therefore be made to ensure that all solutions are kept as nearly as possible at constant temperature. 

CEA involves exposure of the carotid bifurcation in the neck to a point along the internal carotid artery (ICA) beyond which the atherosclerotic plaque terminates. 

Patches are placed on the test subject at designated locations. According to Durham and Wolfe, one patch should be placed on the top of each shoulder one on the upper chest near the jugular notch one on the back of the neck at the edge of the collar one on each upper front leg (thigh area) one on each lower front leg (just below the knees) and one on the back of each forearm. Patches may also be placed on the front and back of a hat or cap to measure exposure to the face and neck area. When collecting the patch samples, one may prefer to combine the two shoulder patches as one sample both lower arm forearm samples as one sample both lower front leg samples as one sample and both upper front leg samples as one sample, in order to examine the entire area of the body that the two patches represent. 

Head, neck, and hand exposures were measured using methods outlined in the literature.4 Head patches were used to estimate dermal exposure to the neck and face of the worker. Handwashes were conducted using a 0.008% DSS solution and collected in 2-L Pyrex bowls. The handwash was repeated with distilled water, and the two handwash solutions were combined. The pooled handwash was then partitioned with ethyl acetate to remove the chlorpyrifos from the aqueous phase. An aliquot of the ethyl acetate was shipped to the analytical laboratory for analysis of chlorpyrifos. 

Add to this value the micrograms chlorpyrifos found in the handwash and head patches (corrected for surface area of the head and neck). This sum in terms of ug/kg body weight per day represents the total dermal exposure (TDE). 

The total unprotected dermal exposure (TUDX) is the sum of the exposure on coveralls, socks, hands, gloves, hat, face, and neck. This represents the maximum potential exposure of the operator, and this value and provides... 

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