Evaluation of folate and vitamin B12 levels in lead exposed workers

Abstract

Objective: Lead (Pb) is a heavy metal and causes dysfunction in hematopoietic, cardiovascular, renal and hepatic systems. The aim of this study is to evaluate the effect of lead exposure on serum vitamin B12 and folate levels.

Methods: 944 patients who were referred to Ankara Occupational Disease Hospital between 2010 and 2014 for periodic examination and whose whole blood lead, serum vitamin B12 and folate levels were assessed are included in this study. 432 patients with whole blood lead levels over 10 μg/dL are defined as exposed group and 512 patients with lead levels below 10μg/dL are considered as control group. Vitamin B12 and folate levels were compared between two groups. Correlation analysis was also performed.

Results: In the lead exposed group the median folate level was 6.3 ng/mL (3.60-17.46) and median vitamin B12 level was 310 pg/mL (180-854) where as folate level was 6.8 (3.60-19.67) ng/mL and median vitamin B12 level was 324 pg/mL (190-833) in the control group. The difference between two groups was statistically significant (p value: <0.001 for folate and 0.015 for vitamin B12). Lead levels correlated negatively with folate levels (r=-0.105; p=0.001). There was no correlation between lead and vitamin B12 (r=-0.061, p=0.062).

Conclusion: This study demonstrated that serum folate and vitamin B12 concentrations were negatively associated with lead exposure. It may be important to keep sufficient levels of these micronutrients to prevent possible harmful effects of Pb exposure regarding hyperhomocysteinemia.

Key words: Lead exposure, vitamin B12, folate

Keywords

• Lead exposure, vitamin B12, folate

Kurşun maruziyeti olan işçilerde folat ve vitamin B12 seviyelerinin değerlendirilmesi

Abstract

Amaç: Kurşun ağır bir metal olup, hematopoetik sistem, kardiyovasküler sistem, renal ve hepatik sistemde disfonksiyona neden olur. Bu çalışmanın amacı kurşun maruziyetinin vitamin B12 ve folat seviyesine etkisinin araştırılmasıdır. Yöntemler: 2010-2014 yılları arasında Ankara Meslek Hastalıkları Hastanesine periyodik muayene amaçlı başvuran tam kan kurşun, serum vitamin B12 ve folat düzeylerine bakılmış 944 kişi çalışmaya dahil edildi. Kurşun seviyesi 10μg/dL’nin üzerinde çıkan 432 kişi kurşun maruz grup, 10μg/dL’nin altında çıkan 512 kişi ise kontrol grubu olarak kullanıldı. Vitamin B12 ve folat düzeyleri iki grup arasında karşılaştırıldı. Ayrıca korelasyon analizi yapıldı. Bulgular: Kurşun maruz grubun median folat seviyesi 6,3 ng/mL (3,60-17,46), median vitamin B12 seviyesi ise 310 pg/mL idi. Kontrol grubunun folat seviyesi 6,8 (3,60-19,67) ng/mL median vitamin B12 seviyesi ise 324 pg/mL idi (p değerleri; folat için <0,001, vitamin B12 için 0,015). Kurşun düzeyi folat seviyesi ile negatif bir korelasyon gösterirken (r=-0.105; p=0.001), kurşun ve vitamin B12 arasında herhangi bir korelasyon yoktu (r=0.061, p=0.062).Sonuç: Bu çalışma folat ve vitamin B12 konsantrasyonu ile kurşun maruziyeti arasında negatif bir ilişki olduğunu gösterdi. Bu durum hiperhomosisteinemi açısından kurşunun olası zararlı etkilerini önlemek için bu vitaminlerin yeterli miktarda alınması açısından önemli olabilir

Keywords

• Kurşun maruziyeti, vitamin B12, folat

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