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Study on the effects of nitrilotriproprionic acid and 4,5-dihydroxy-1,3-benzene disulphonate on the fractionation of beryllium in human serum using graphite furnace atomic absorption spectrometry.

Stephan CH, Fournier M, Brousseau P, Sauvé S - Chem Cent J (2008)

Bottom Line: Molecular studies have found a significant correlation between the electrostatic potential at the HLA-DP surface and disease susceptibility.On average, three quarters of the beryllium in serum were found in the HMW fraction.Of the two ligands tested, only Tiron was effective in mobilising beryllium under physiological conditions, thus increasing the Be content in the HMW fraction.

View Article: PubMed Central - HTML - PubMed

Affiliation: Department of Chemistry, Université de Montréal, Montréal, QC, Canada. chadi.stephan@umontreal.ca

ABSTRACT

Background: Occupational exposure to beryllium may cause Chronic Beryllium Disease (CBD), a lung disorder initiated by an electrostatic interaction with the MHC class II human leukocyte antigen (HLA). Molecular studies have found a significant correlation between the electrostatic potential at the HLA-DP surface and disease susceptibility. CBD can therefore be treated by chelation therapy. In this work, we studied the effect of two complexing agents, nitrilotriproprionic acid (NTP) and 4,5-dihydroxy-1,3-benzene disulphonate (Tiron), on the fractionation of beryllium in human serum analysed by graphite furnace atomic absorption spectrometry (GFAAS).

Results: We found the average serum beryllium concentration of fourteen non-exposed individuals to be 0.53 (+/- 0.14) microg l(-1), with 21 (+/- 3)% of the beryllium mass bound to the low molecular weight fraction (LMW), and 79 (+/- 3)% bound to the high molecular weight fraction (HMW). The addition of Tiron increased the beryllium mass in the HMW fraction, while NTP was not seen to have any influence on the fractionation of beryllium between the two fractions. NTP was, however, shown to complex 94.5% of the Be mass in the LMW fraction. The beryllium GFAAS detection limit, calculated as three times the standard deviation of 10 replicates of the lowest standard (0.05 microg L(-1)), was 6.0 (+/- 0.2) ng L(-1).

Conclusion: The concentration of beryllium or its fractionation in human serum was not affected by sex or smoking habit. On average, three quarters of the beryllium in serum were found in the HMW fraction. Of the two ligands tested, only Tiron was effective in mobilising beryllium under physiological conditions, thus increasing the Be content in the HMW fraction.

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Influence of NTP on the repartition of beryllium between the HMW and the LMW fractions in three non-spiked individuals. * Significant difference calculated by One-Way Anova, Fisher's LSD.
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Figure 7: Influence of NTP on the repartition of beryllium between the HMW and the LMW fractions in three non-spiked individuals. * Significant difference calculated by One-Way Anova, Fisher's LSD.

Mentions: NTP did not show any significant influence on the beryllium partitioning either in spiked or non-spiked samples (Figures 6 and 7). In spiked samples, the HMW average beryllium fractionation did not change significantly (One-Way Anova, Fisher's LSD, with P < 0.05) with increasing NTP concentration. We obtained a stable pattern that varied from 76 (± 4)% for the control to 77 (± 5)% at 10-3 M. Similar observations were observed in non-spiked samples. The HMW average beryllium content pattern varied from 77 (± 5)% for the control to 80 (± 4)% at 10-3 M. Under physiological serum conditions, NTP did not influence the MW distribution of Be between the HMW and LMW fractions, but showed a capacity to complex most of the beryllium in the LMW, as shown by the chemical speciation simulations (Figure 8). At a concentration of 10-7 M, NTP was shown to complex 94.5% of the Be in the LWM followed by 3.4% and 1.1% of the Be occurring as Be(OH)+ and BeCO3, respectively. These results support earlier findings which suggest that NTP would be an ideal complexing agent for Be [14].


Study on the effects of nitrilotriproprionic acid and 4,5-dihydroxy-1,3-benzene disulphonate on the fractionation of beryllium in human serum using graphite furnace atomic absorption spectrometry.

Stephan CH, Fournier M, Brousseau P, Sauvé S - Chem Cent J (2008)

Influence of NTP on the repartition of beryllium between the HMW and the LMW fractions in three non-spiked individuals. * Significant difference calculated by One-Way Anova, Fisher's LSD.
© Copyright Policy - open-access
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC2396160&req=5

Figure 7: Influence of NTP on the repartition of beryllium between the HMW and the LMW fractions in three non-spiked individuals. * Significant difference calculated by One-Way Anova, Fisher's LSD.
Mentions: NTP did not show any significant influence on the beryllium partitioning either in spiked or non-spiked samples (Figures 6 and 7). In spiked samples, the HMW average beryllium fractionation did not change significantly (One-Way Anova, Fisher's LSD, with P < 0.05) with increasing NTP concentration. We obtained a stable pattern that varied from 76 (± 4)% for the control to 77 (± 5)% at 10-3 M. Similar observations were observed in non-spiked samples. The HMW average beryllium content pattern varied from 77 (± 5)% for the control to 80 (± 4)% at 10-3 M. Under physiological serum conditions, NTP did not influence the MW distribution of Be between the HMW and LMW fractions, but showed a capacity to complex most of the beryllium in the LMW, as shown by the chemical speciation simulations (Figure 8). At a concentration of 10-7 M, NTP was shown to complex 94.5% of the Be in the LWM followed by 3.4% and 1.1% of the Be occurring as Be(OH)+ and BeCO3, respectively. These results support earlier findings which suggest that NTP would be an ideal complexing agent for Be [14].

Bottom Line: Molecular studies have found a significant correlation between the electrostatic potential at the HLA-DP surface and disease susceptibility.On average, three quarters of the beryllium in serum were found in the HMW fraction.Of the two ligands tested, only Tiron was effective in mobilising beryllium under physiological conditions, thus increasing the Be content in the HMW fraction.

View Article: PubMed Central - HTML - PubMed

Affiliation: Department of Chemistry, Université de Montréal, Montréal, QC, Canada. chadi.stephan@umontreal.ca

ABSTRACT

Background: Occupational exposure to beryllium may cause Chronic Beryllium Disease (CBD), a lung disorder initiated by an electrostatic interaction with the MHC class II human leukocyte antigen (HLA). Molecular studies have found a significant correlation between the electrostatic potential at the HLA-DP surface and disease susceptibility. CBD can therefore be treated by chelation therapy. In this work, we studied the effect of two complexing agents, nitrilotriproprionic acid (NTP) and 4,5-dihydroxy-1,3-benzene disulphonate (Tiron), on the fractionation of beryllium in human serum analysed by graphite furnace atomic absorption spectrometry (GFAAS).

Results: We found the average serum beryllium concentration of fourteen non-exposed individuals to be 0.53 (+/- 0.14) microg l(-1), with 21 (+/- 3)% of the beryllium mass bound to the low molecular weight fraction (LMW), and 79 (+/- 3)% bound to the high molecular weight fraction (HMW). The addition of Tiron increased the beryllium mass in the HMW fraction, while NTP was not seen to have any influence on the fractionation of beryllium between the two fractions. NTP was, however, shown to complex 94.5% of the Be mass in the LMW fraction. The beryllium GFAAS detection limit, calculated as three times the standard deviation of 10 replicates of the lowest standard (0.05 microg L(-1)), was 6.0 (+/- 0.2) ng L(-1).

Conclusion: The concentration of beryllium or its fractionation in human serum was not affected by sex or smoking habit. On average, three quarters of the beryllium in serum were found in the HMW fraction. Of the two ligands tested, only Tiron was effective in mobilising beryllium under physiological conditions, thus increasing the Be content in the HMW fraction.

No MeSH data available.


Related in: MedlinePlus