|
| Forside | | Indhold | | Forrige | | Næste |
Systemisk kontakteksem over for nikkel ved oral eksponering
Summary and conclusions
Systemic contact dermatitis can be elicited in nickel-sensitized individuals by oral intake of nickel under experimental conditions. The crucial point in the interpretation of such experiments has been the
relevance of the experimental results to normal oral intake of nickel from drinking water and diet.
In the current investigation an adjusted dose-response meta-analysis of the experimental results in the available published literature was performed. The aim was to provide the best possible estimation of
doses of nickel that may cause systemic reactions, as a basis for decision making e.g. in relation to the establishment of limit values for drinking water.
An extensive literature search was made in MEDLINE, EMBASE and BIOSIS, and 17 scientific papers concerning experimental oral nickel exposure and systemic contact dermatitis were identified. The
studies were not directly comparable, and for this reason the statistical analysis was performed in a step-wise procedure. In the resulting analysis nine studies were included, which from a statistical point of
view were comparable, concerned a single oral exposure dose and included a negative placebo control. These nine studies included 171 patients and could be divided into further three groups: A
homogenous middle group of five studies, and two groups of two studies each with a higher and lower response frequency, which could be described by dose-response curves shifted in parallel. Based on
these dose-response curves, an estimation was made concerning the doses, which theoretically would give response in 50% of the exposed (ED50), 25% (ED25), 10% (ED10), 5% (ED5) and 1% (ED1)
of the exposed nickel sensitized eczema patients.
Overview of estimated doses for (ED50) and lower responses
| Ni-doses |
Study 2+3+4+8+10 |
Study 1+11 |
Study 9+14 |
| (mg) |
Estimat
e |
95 % limits |
Estimat
e |
95 % limits |
Estimat
e |
95 % limits |
| ED50 |
2.00 |
1.47-2.35 |
3.06 |
2.15-4.30 |
1.27 |
0.77-1.72 |
| ED25 |
1.32 |
0.68-1.69 |
2.01 |
1.13-2.74 |
0.83 |
0.37-1.19 |
| ED10 |
0.87 |
0.31-1.26 |
1.33 |
0.53-1.94 |
0.55 |
0.17-0.86 |
| ED5 |
0.65 |
0.18-1.04 |
1.00 |
0.31-1.57 |
0.41 |
0.10-0.70 |
| ED2 |
0.45 |
0.09-0.81 |
0.70 |
0.16-1.21 |
0.29 |
0.05-0.54 |
| ED1 |
0.35 |
0.05-0.67 |
0.53 |
0.09-1.00 |
0.22 |
0.03-0.45 |
The results from the two most sensitive groups of nickel-allergic eczema patients show that 1% of these sensitive individuals may react with a systemic contact eczema at exposures to 0.22 to 0.35 mg nickel
in addition to their normal diet. It is roughly estimated that this will concern about 20 new cases of nickel-sensitive eczema patients per year seen by dermatologists in Denmark. The real frequency may be
higher, as not everybody with a problem will see a dermatologist. On the other hand, it is expected that this estimate will cover most of the severe cases.
| Forside | | Indhold | | Forrige | | Næste | | Top |
Version 1.0 Juni 2005, © Miljøstyrelsen.
|