Gitte D. Nielsen

Nickel content of food and estimation of dietary intake

ZusammenfassungEs wird zusammenfassend über den Nickelgehalt von Lebensmitteln berichtet. Ein gründliches Wissen darüber ist von Bedeutung, da die Dermatologen der Ansicht sind, daß das Wiederauftreten von Handekzemen auf perorale Nickelaufnahme zurückgeführt werden kann. Das Überhandnehmen der Nickelallergie in der dänischen Bevölkerung ist bei Frauen 10% und bei Männern 2%. Die Nickelaufnahme durch die dänische Kost wird durchschnittlich auf 150 μg/Person/Tag geschätzt. Wurzelgemüse und anderes Gemüse, Mehl, Grütze und Brot tragen zum Nickelgehalt in der Kost relativ viel bei. Spezielle Lebensmittel, wie Kakao und Schokolade, Sojabohnen, Haferflocken, Nüsse und Mandeln, frische und getrocknete Hülsenfrüchte, haben hohe Nickelgehalte. Der Verzehr dieser Produkte in größeren Mengen kann die Nickelaufnahme bis zu 900 μg/Person/Tag oder mehr erhöhen. Dieses ist innerhalb des Bereiches von 600-5 600 μg Nickel, der das Handekzem provozieren kann, wenn es als einzelne Dosis als Nickelsulphat gegeben wird. Die Frage ist, ob Nickel in der Kost Handekzeme provozieren kann. Dieses kann nur und sollte auch durch Studien über Diäten mit wenig bzw. viel Nickel aufgeklärt werden.SummaryNickel contents of foods are reviewed. A thorough knowledge of nickel in food is of new relevance. Among dermatologists it is a general opinion that flare of hand eczema can occur after per oral nickel exposure. The prevalence of nickel allergy in the Danish population is 10% for women and 2% for men. Nickel intake from the Danish diet is estimated as 150 μg/person/day on average. Roots and vegetables, meal, grain and bread relatively supply the average diet with much nickel. Certain food items, e.g. cocoa and chocolate, soya beans, oatmeal, nuts and almonds, fresh and dried legumes, have very high nickel contents. Consumption of these items in larger amounts may increase the nickel intake to 900 μg/person/day or more. Within the range of 600-5,600 μg of nickel may provoke hand eczema, when given in single doses as nickel sulphate. An obvious question is thus whether nickel in the diet can cause flare of hand eczema. This should and can only be established by provocation studies with low-level nickel diets combined with a single food having a high nickel content.

Effects of Industrial Detergents on the Barrier Function of Human Skin

Abstract Detergents are involved in the causation of contact dermatitis and in promoting percutaneous absorption of toxic chemicals, but limited information is available to allow an assessment of their relative effects on the skin barrier function. The effect of detergents on skin permeability to water and nickel was examined in an in-vitro model using human skin. Twenty four of the most widely used detergents were studied. After a two-hour exposure to an aqueous detergent solution, penetration of labeled model compounds was followed for 66 hours. Interindividual variation was substantial, but 12 of the detergents caused statistically significant increases in the penetration of water, nickel, or both. Nonionic detergents were as likely as anionic detergents to have this effect. This study demonstrates that useful information may be obtained by a simple in-vitro method, and that such data may provide a basis for substitution efforts.

Effect of sodium lauryl sulfate (SLS) on in vitro percutaneous penetration of water, hydrocortisone and nickel

The dose‐ and time‐related effect of sodium lauryl sulfate (SLS) on in vitro percutaneous penetration was studied using 3 radiolabeled tracer compounds with different physicochemical properties: tritiated water, hydrocortisone and nickel. Human cadaver abdominal skin from caucasian women was used as membrane in static in vitro penetration cells. Simultaneous application of SLS together with 1 of the tracer compounds showed, after 48 h, a significant dose‐effect relationship between SLS concentration (0.25%, 2% and 10%) and penetration of tritiated water or nickel (p < 0.001, Spearman), whereas SLS had no significant effect on penetration of hydrocortisone. When 4% SLS was applied as pretreatment, a significant time‐effect relationship, after 48 h, was found between pretreatment time (0.5, 2 and 8 h) and penetration of tritiated water. A similar relationship was not found for penetration of nickel or hydrocortisone. Pretreatment of the skin with SLS for 2 h using 3 concentrations (0.25%, 4% and 10%) showed, after 48 h, a significant dose‐effect relationship between SLS treatment and penetration of tritiated water or nickel (p < 0.001, Spearman). Pretreatment had no effect on penetration of hydrocortisone. Pretreatment simulates a cleaning‐washing situation. The present in vitro skin penetration model, using human cadaver skin, described the dose‐effect and time‐effect relationships for SLS on the penetration profiles of 3 different compounds. The model may be extended to other compounds with suspected irritant/damaging effect on the skin barrier. It should be kept in mind that the model uses a dead skin membrane without the barrier repair mechanisms of live skin.

Colorimetric quantification of erythema in the guinea pig maximization test.

Reading of test reactions in the guinea pig maximization test (GPMT) is usually done by visual scoring, i.e., Magnusson & Kligmans (!)scale: O=no visible change, I =slight or discrete erythema, 2=rnoderate and confluent erythema, 3 =intense erythema and swelling. This adds to such ratings a subjective element, which is circumvented by including shamtreated control animals in any test to allow for blind reading of the responses. Wei! & Scala (2) concluded, in their study of intraand interlaboratory variability in irritation tests in rabbits, that a significant reason for variability was inter-individual variation in visual scoring and rating. Visible erythema and palpable edema are the main characteristics of the contact allergy test reactions used for scoring in guinea pig tests. Attempts have been made to quantify contact allergy reactions by using laser Doppler flowrnetry and skin fold thickness readings as a measure of erythema and edema, respectively (3). Though the visual judgment of a trained observer seems fast and reliable, new objective reading methods that have been developed, deserve to be evaluated. Colorimetric measurement was useful as an objective method of evaluating erythema in an irritancy test with sodium Iaury! sulphate (SLS) (4). This report compares visual readings with quantification of changes in erythema in challenge patch test reactions in the GPMT.

Dose response relationship in the guinea pig maximization test with nickel sulphate

Carbamazepine (CBZ, Tegretol®) is a widely used anti-epileptic drug, which is usually well-tolerated. However, skin reactions are reported in 3-30% of CBZ-users. The relative frequency of allergic skin reactions is unclear. Oxcarbazepine (OCB, TrileptaJ®), a ketoanalogue of CBZ, is a possible alternative for patients allergic to CBZ. 25 patients with a history of previous skin reactions to CBZ were enrolled in the study. 10 patients receiving CBZ without any signs of reactive skin eruptions served as controls. Patch tests and lymphocyte proliferation assays (LP A) were performed using CBZ, OCB and their metabolites CBZ-10, 11-epoxide, monohydroxycarbazepine and 10, 11-dihydroxy-CBZ. Additional patch tests were performed with ground CBZ and OCB tablets. In vitro lymphocyte proliferation showed positive results in 8 cases, whereas patch tests were positive in 6. In 4 patients, both LP A and patch tests were positive. In our opinion, these data indicate that the LPA is a valuable additional tool in diagnosing CBZ-allergy. The predictive value and possible implications for clinical practice will be discussed.