Hydroxyisohexyl 3-cyclohexene carboxaldehyde- known as Lyral: quantitative aspects and risk assessment of an important fragrance allergen.

Hydroxyisohexyl 3-cyclohexene carboxaldehyde, also known as Lyral, is a fragrance ingredient identified as the cause of contact allergic reactions in 2-3% of eczema patients undergoing patch testing. Lyral has been included in the standard patch test series in many clinics due to its importance as an allergen. It has been used without restrictions in cosmetic products, until now. In the present study, the dose-response relationship of Lyral contact allergy was studied with doses relevant for normal exposure in cosmetic products. 18 eczema patients, who previously had given a positive patch test to Lyral 5% petrolatum, were included along with 7 control subjects. All cases were tested with a serial dilution of Lyral in ethanol 6% to 6 p.p.m and subjected to a 2-week, repeated open application test with a low dose of Lyral in ethanol. In the case of no reaction, this was followed by another 2 weeks of testing with a higher dose. The test was performed at the volar aspect of the forearm. In 16 of 18 cases (89%), a positive use test developed, 11 reacting to the low and 5 to the high concentration. None reacted to the vehicle control of ethanol applied to the contralateral arm. All controls were negative to both the test solutions of Lyral and the ethanol control. The difference between the test and the control group was statistically significant (Fisher's test, P < 0.001). It is concluded that Lyral at the current usage levels is inducing sensitization in the community. The same levels were shown to elicit allergic contact dermatitis in almost all sensitized individuals. A significant reduction in usage concentrations is recommended to prevent contact allergic reactions.

An assessment of dialysis-associated osteodystrophy in long-term peritoneal dialysis.

To assess the development of dialysis-associated osteodystrophy during intermittent peritoneal dialysis, a study was made of 50 patients with end-stage renal failure. The duration of dialysis therapy ranged from 6 to 37 months, during which the peritoneal dialysis index for creatinine fell from 5.7 to 2.9 ml/min. Serum calcium normalized from predialytic values below normal range. During the period of observation there were no significant changes in serum albumin, phosphate, magnesium, ionized calcium or parathyroid hormone levels. Osteodensitometry, performed on 26 patients, revealed no significant changes. Determination of serum total alkaline phosphatases (TALP) and fractioned alkaline phosphatases showed raised TALP values in 30% of the patients; in only 10% of these patients the increase was due to elevated liver isoenzymes. 6 patients had normal TALP but relatively raised bone isoenzyme values. There was a significant correlation between the bone fraction and TALP, and between the liver fraction and TALP, but none between the bone and liver fraction. Patients on intermittent peritoneal dialysis using a dialysis fluid with a relatively high calcium concentration (2.25 mmol/l) seem less prone to develop dialysis-associated osteodystrophy.

Cost benefit of patch testing with textile finish resins.

Eleven years experience of textile finish resin patch testing of suspected textile dermatitis patients revealed 15 cases of allergic textile dermatitis among 428 patients tested. Ten of the 15 patients had a relevant positive patch test to one or more of a limited series of textile finishes; 1 was negative and 4 were not tested with textile finishes. All 15 patients were formaldehyde sensitive. No unexpected, relevant, positive textile finish resin patch test was found. In this study a negative patch test to formaldehyde virtually excluded allergic contact dermatitis from textile finishes.