Blood levels of polycyclic aromatic hydrocarbons in children and their association with oxidative stress indices: an Indian perspective.
BACKGROUND
Polycyclic aromatic hydrocarbons (PAHs), some ubiquitous environmental contaminants are capable to cause oxidative stress, during its metabolism. It is believed that many diseases that have a common origin in oxidative stress begin in childhood. Considering oxidative stress evolved during PAHs metabolism as one main mechanism responsible for health hazards related to PAHs exposure in children, we biomonitored blood PAHs levels in connection with redox status among children of Lucknow (India).


METHODS
The study consisted of children (n = 50) who visited to the Pediatrics Department (KGMU) Lucknow for usual health check-up camp over the study period (August 2005-July 2006). Blood samples were drawn and levels of acenaphthylene, anthracene, phenanthrene, fluoranthene, naphthalene, pyrene, benzo(b)fluoranthene, benzo(k)fluoranthene and benzo(a)pyrene were determined by HPLC-FD/UV. Malondialdehyde (MDA), glutathione (GSH) levels, catalase (CAT) and superoxide dismutase (SOD) activity were also determined to evaluate redox status.


RESULTS
Significantly elevated carcinogenic blood PAHs levels (125.55 +/- 26.99ppb, p < 0.05) were found in rural children compared to children from urban region (23.96 +/- 13.46). Results revealed that remoteness between residence and highway/traffic, significantly influences the blood levels of carcinogenic PAHs. There were significant correlations between total PAHs and MDA (r = 0.82, p < 0.001), carcinogenic PAHs and SOD activity (r = 0.35, p < 0.01), Total PAHs and blood GSH level (r = - 0.49, p < 0.01) and carcinogenic PAHs and CAT activity (r = 0.42, p < 0.01). Blood MDA level was also found correlated with increasing body mass index (BMI) (r = 0.29, p < 0.05).


CONCLUSIONS
Our results showed blood PAHs levels in children significantly correlated with oxidative stress and altered antioxidant status. It supports our hypothesis that the children exposed to high PAHs level will suffer more to oxidative stress that may lead to possible health risks. Additional studies with large sample size are considered necessary to strengthen the database and also to explore the PAHs associated health risks in children.
D002274:Carcinogens, Environmental; D002374:Catalase / Q000097:blood / Q000187:drug effects; D002648:Child; D002675:Child, Preschool; D004781:Environmental Exposure / Q000032:analysis*; D004784:Environmental Monitoring; D004785:Environmental Pollutants / Q000097:blood* / Q000737:chemistry; D005978:Glutathione / Q000097:blood / Q000187:drug effects; D006801:Humans; D007194:India; D008315:Malondialdehyde / Q000097:blood; D018384:Oxidative Stress; D011084:Polycyclic Aromatic Hydrocarbons / Q000097:blood* / Q000737:chemistry; D012189:Retrospective Studies; D012424:Rural Population; D013482:Superoxide Dismutase / Q000097:blood / Q000187:drug effects; D014028:Tobacco Smoke Pollution; D014505:Urban Population; D001335:Vehicle Emissions
D002274:Carcinogens, Environmental; D004785:Environmental Pollutants; D011084:Polycyclic Aromatic Hydrocarbons; D014028:Tobacco Smoke Pollution; D001335:Vehicle Emissions; D008315:Malondialdehyde; D002374:Catalase; D013482:Superoxide Dismutase; D005978:Glutathione