Volar forearm

Dermal Effects. w-Hexane was 1 of 11 solvents tested for dermal toxicity in a male volunteer (Wahlberg 1984). Analytical grade -hcxanc (1.5 mL test area, 3.1 cm2) within a glass ring was applied to the volar forearm of the volunteer and left on the skin for 5 minutes. Blood flow values (expressed as a relative, dimensionless value) after dermal application of 1.5 mL of neat -hexane appeared to increase... 

Creams containing 3% urea (n = 23) or 10% urea (n = 24) were applied to one of the volar forearms on individuals with some evidence of dry skin for three weeks.38 Both creams improved the skin with respect to dryness characteristics, as evaluated by a dermatologist, measurements of electrical capacitance and conductance, and tape assessments of scaling. Both creams were considered equally effective.38... 

FIGURE 32.5 Amplitude/mean measurements for interventions. The application of glycerin and the PVDC occlusion increased the amplitude/mean of the volar forearm. Also, the addition of glycerin raised the amplitude/mean significantly more than the PVDC occlusion. Petrolatum significantly decreased the amplitude/mean and this is a quantitative evidence of petrolatum s greasiness (P <. 001). Reproduced from Sivamani et al.24... 

The friction coefficient varies with anatomical site Cua et al.8,22 found that friction coefficients varied from 0.12 on the abdomen to 0.34 on the forehead. Eisner etal.11 measured the vulvar friction coefficient at 0.66, whereas the forearm friction coefficient was 0.48. Sivamani et al.24 found that the proximal volar forearm had a higher friction coefficient than the distal volar forearm. Manuskiatti et al.23 studied skin roughness and found significant differences in skin roughness at various anatomical sites. Differences in environmental influences (i.e., sun exposure) and hydration may account for this. Eisner et al.11 showed that the more-hydrated vulvar skin had a 35% higher friction coefficient than the forearm, and this is in agreement with hydration studies that contend that skin has an increased friction coefficient under increased hydration. 

FIGURE 32.6 Age related comparisons of friction and electrical impedance. No significant differences were apparent between old and young skin on the volar forearm. Within each category, the proximal right arm friction and electrical impedance measurements were different from the distal right arm (P <. 001). Reproduced from Sivamani et al24... 

FIGURE 32.7 Coefficient of friction across ethnicity. Data represents increase in friction when compared to untreated skin of the volar forearm. No significant differences were found between the different ethnic groups. Petrolatum and glycerin increased the friction coefficient significantly more than PVDC occlusion (P <. 01). The increase in the friction coefficient due to petrolatum was not significantly different from the effect of glycerin. Reproduced from Sivamani et al.24... 

FIGURE 37.4 SLS irritation and moisturizer treatment, (a) No significant differences in skin color (a-values) were detectable with the Chromameter. (b) The same sites as in (a) scanned with the laser Doppler imager showed marked reduction of erythema. Volar forearms were treated with a water-in-oil emulsion twice daily for four weeks. Statistical significance was determined using the paired r-test ( p >. 05, p <. 01). 

The volar forearm is a fairly sensitive area of the body as it does not receive a great deal of exposure to the sun. Up to three different products can be tested on each arm and are applied up to six times per day for three consecutive weeks, with the sites assessed at regular intervals by trained skin assessors. 

Volar forearm, dorsal hand and finger sites showed lower site-dependent baseline flux, but did vasodilate. Anaesthetic effect 3.6min for scrotum vs. 1 hr + for abdomen... 

Figure 10.2 Cumulative evaporation of fragrance ingredients described from a human volar forearm (Vuilleumier et al., 1995), extrapolated to infinite time (Kasting and Saiyasombati, 2001). The value of k in Equation 10.7 was calculated as k = 1.5/9.1 = 0.165 (Table 1, Vector B).

In skin testing, the central area of die volar forearm is very popular, mainly because of ease of access. It is also considered very homogeneous and stable, compared with other areas of the human body, and in extrapolation of this belief there have been studies without randomization of test sites within the volar forearm region. In search of suitable... 

FIGURE 37.13 Activity of CN, antioxidant and immunomodulant compounds on lipid peroxides found on volar forearm of women affected by dry skin. 

Right volar forearm Phase 1 (PI) and Phase 2 (P2) Antecubital fossa Outwards a H2O occl. b Empty control c 0.5% SDS occl. d 1% SDS occl. e 2% SDS occl. Wrist... 

However, daily open treatments with solvents (neat) for 10-18 days on human volar forearms did not cause any increase in skin-fold thickness (Wahiberg 1993). A transient erythema immediately after the administration of toluene was observed in a few cases. The absence of oedema-inducing effects in man compared with rabbits and guinea pigs is probably due to evaporation of solvents immediately after administration to man, while solvents partly adhered to the animals fur. 

Skin prick tesT Undiluted contrast media solution. For standard procedure, see Sect. 4.2.2 Volar forearm After 20 min and on days 2 and 3 Immediate reaction Wheal>3 mm after 20 min Delayed reaction Erythematous induration at site on day 2 or 3... 

When comparing several products on the volar forearm of volunteers, it is highly recommended to randomize products among sites, or when pair comparison have to be done, to apply the products on the same contralateral right and left sites. Indeed, differences between contralateral sites seem to be minimal unless externally induced [149]. 

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