imagem top



CHULC LOGOlogo HDElogo anuario


Inês Salva1,2, João Carmo3, Luís Pereira-da-Silva1,4, Mauro Guerra3, José Paulo Santos3, João Goyri O’Neill2

1 - NICU, Hospital Dona Estefânia, Centro Hospitalar de Lisboa Central;
2 - Anatomy Department, NOVA Medical School, Universidade NOVA de Lisboa;
3 - Physics Department, Faculty of Science and Technology, Universidade NOVA de Lisboa;
4 - Woman, Children and Adolescent's Medicine Teaching and Research Area, NOVA Medical School, Universidade NOVA de Lisboa; Lisbon, Portugal

- 1st International Caparica Conference on Pollutant Toxic Ions and Mollecules. Caparica, 02/11/2015 (Poster)

Purpose: Determination of the trace element profiling of the hair in the neonate according to gestational age. 
Experimental description: Trace element profiling using energy dispersion X-ray fluorescence technique in a sample of 80 neonates divided in groups according to gestational age.
Results: The composition of the studied elements in the analysed hairs between the control and the samples is the amount of aluminium. It was also verified that along each hair the concentration of most remains the same, i.e. their composition is about the same from root to tip. Regarding the analysed elements, sulphur has the highest relative concentration, ranging from 86-90%, followed by chlorine with 5-7% and calcium with 1-3%. The relative concentration of the remained studied elements is below 1% each. Furthermore, as the gestational age increases from group to group, the values of aluminium, iron, copper and zinc decrease land those of sulphur and phosphorus increase. On the other hand, chlorine, calcium and silicon, don’t present apparent tendency for different gestational ages.
In terms of the total amount of trace elements, it was recorded for full-term, late preterm, very preterm and extreme preterm, the respective values of 20100±2200, 15300±1800, 12700±1500 and 9600±1400 mg/kg. The verified differences have weak evidence of significance. This can be attributed to the low volume of the samples and to other factors that may also contribute to the absorption of nutrients by the fetus besides the gestational age. Besides the differences verified between groups there was a substantial gap between them and the values obtained for the standard and adult sample, respectively, 64200±2700 and 49100±2600 mg/kg. These differences are very likely due to, again, the low volume of the samples and the heterogeneity of the hairs themselves. Finally, it’s interesting to note that in some of the samples it was possible to observe the presence of iodine, signalling, most likely, some type of contamination at the time of labour.
Conclusions: The goal of the study was reached, as it was possible to analyse and differentiate the concentration of trace elements in different gestational age groups. During the study it was noticed that the data obtained is somewhat dependent on the volume analysed since the studied hairs were on the same scale as the focal spot of the spectrometer. As such, the obtained values are affected by a systematic uncertainty. One possible solution could be using tablets made out of the analysed samples. However, considering that the donors are neonates, most of which preterm, it’s highly doubtful that there would be enough hair samples in each donor to make a tablet and/or that the parents would give permission to remove such a considerable amount of their children’s hair.

Palavras Chave: hair, neonate, ultrastructure, trace element, X-ray fluorescence