The effects of air pollution on vitamin D status in healthy women: a cross sectional study.
BACKGROUND
Inadequate radiation or insufficient cutaneous absorption of UVB is one of the cardinal causes of vitamin D deficiency. The aim of this study is to determine whether air pollution and low ground level of ultra-violet B light (UVB; 290-315) can deteriorate the body vitamin D status in healthy women.


METHODS
In this cross sectional study 200, free-living, housewives, aged between 20 to 55 years, from Tehran (high polluted area) and Ghazvin (low polluted area) were included. The Tehranian women were selected randomly from participants of the Tehran Lipid and Glucose Study (TLGS) and the Ghazvinian females from patients who came to public health centers. Participants were excluded for disease and drugs which affect vitamin D status and also if they were pregnant or breast feeding. We measured the ground level of UVB using a Haze meter as a surrogate of air pollution. In order to calculate the adjusted mean difference of 25-OH-D, ANCOVA analysis was used. Moreover, Binary logistic regression model was developed to determine the odds of living in Tehran for having serum 25-OH-D less than 20 ng/ml.


RESULTS
The mean ± SD of serum 25-OH-D was significantly higher in Ghazvinian women ((18 ± 11 vs. 13 ± 7), P-value < 001). The prevalence of 25-OH-D less than 10 ng/ml, and 25-OH-D between 10 and 20 ng/ml were higher in Tehranian group (36% and 54% vs. 31% and 32% in respectively). Secondary hyperparathyroidism was also significantly higher in Tehranian women (47% vs. 32%). In ANCOVA analysis, after adjustment, the mean of 25-OH-D in the Ghazvinian group was still statistically significantly higher than Tehranians (13 vs. 17 ng/ml P-value = 0.04). In addition, in binary logistic model, the odd of living in Tehran for having serum 25-OH-D less than 20 ng/ml was 5.22 (95% confidence interval 2.2-12.2, P-value < 0.001).


CONCLUSIONS
We found that living in a polluted area plays a significant independent role in vitamin D deficiency and hence, residence can be one of the main reasons of vitamin D status of the women.
Hosseinpanah
Farhad
F
Obesity Research Center, Research Institute for Endocrine Sciences, Shahid Beheshti University of Medical Sciences, PO Box 193-4763, Tehran, Iran. fhospanah@endocrine.ac.ir
Pour
Sima Hashemi
SH
Heibatollahi
Motahare
M
Moghbel
Nilufar
N
Asefzade
Saeed
S
Azizi
Fereidoun
F
D000328:Adult; D000397:Air Pollution / Q000009:adverse effects*; D003430:Cross-Sectional Studies; D005260:Female; D006801:Humans; D007492:Iran; D008875:Middle Aged; D014807:Vitamin D / Q000097:blood*; D055815:Young Adult
D014807:Vitamin D
Arch Dis Child. 2002 Aug;87(2):111-3
12138058
Arch Biochem Biophys. 2007 Apr 15;460(2):213-7
17254541
BMC Public Health. 2006 May 19;6:135
16712731
J Clin Invest. 1985 Oct;76(4):1536-8
2997282
Evid Rep Technol Assess (Full Rep). 2007 Aug;(158):1-235
18088161
Semin Arthritis Rheum. 2009 Jun;38(6):444-51
18336870
J Clin Endocrinol Metab. 2008 Oct;93(10):3893-9
18628525
J Intern Med. 2000 Feb;247(2):260-8
10692090
Am J Clin Nutr. 1995 Mar;61(3 Suppl):638S-645S
7879731
J Endocrinol Invest. 2007 Sep;30(8):653-8
17923796
Lancet. 1998 Mar 14;351(9105):805-6
9519960
Public Health Nutr. 2004 Apr;7(2):327-35
15003141
Public Health Nutr. 2010 May;13(5):654-62
19807937
J Air Waste Manag Assoc. 2003 Feb;53(2):237-45
12617297