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Updated: Jun 4, 2026
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Telomere Length and Telomerase Activity; A Yin and Yang of Cell Senescence
Published on: May 22, 2013
N-nitrosamines are associated with shorter telomere length
Huiqi Li1, Bo A G Jönsson, Christian H Lindh
1Section of Occupational and Environmental Medicine, Lund University Hospital, SE-221 85 Lund, Sweden.
Scandinavian Journal of Work, Environment & Health
|February 16, 2011
Summary
Exposure to N-nitrosamines in the rubber industry may shorten telomeres, the protective caps on chromosomes. This study investigated DNA-damaging agents and telomere length in 157 Swedish workers.
Area of Science:
- Environmental Health
- Molecular Biology
- Occupational Medicine
Background:
- Telomeres are crucial for chromosomal integrity, and their abnormalities are linked to cancer.
- Individual telomere length is influenced by genetic and environmental factors.
- The rubber industry involves exposure to various DNA-damaging agents.
Purpose of the Study:
- To investigate the association between exposure to DNA-damaging agents and average telomere length in peripheral blood.
- To assess occupational exposure risks in the rubber industry.
Main Methods:
- A cross-sectional study of 157 workers in the Swedish rubber industry.
- Measurement of N-nitrosamines in air, polycyclic aromatic hydrocarbons (PAH) via 1-hydroxypyrene (1-HP) in urine, carbon disulfide (CS2) via 2-thiothiazolidine-4-carboxylic acid (TTCA) in urine, and toluidines in urine.
- Average telomere length in peripheral blood was determined using quantitative polymerase chain reaction (PCR).
Main Results:
- Increased exposure to N-nitrosamines was associated with reduced telomere length (p=0.016).
- Para-toluidine exposure and older age were also negatively correlated with telomere length (p=0.014 and p=0.001, respectively).
- No significant associations were found for other measured exposures, and smoking did not modify the effects.
Conclusions:
- N-nitrosamines exposure is a potential factor contributing to telomere shortening.
- Occupational exposure to specific chemicals may impact cellular aging markers like telomere length.
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