Vipul K. Singh

Comparison of polycyclic aromatic hydrocarbon levels in placental tissues of Indian women with full- and preterm deliveries

Polycyclic aromatic hydrocarbons (PAHs) are ubiquitous environmental contaminants formed from combustion products of fossil fuels, cigarette smoking and in grilled/smoked foods. They are reported to alter trophoblast proliferation in placenta, in addition to disturbing its endocrine functions, which may be able to increase the risk of preterm delivery in pregnant women. The present study was planned to assess possible involvement of PAHs exposure of pregnant women (measured as placental PAHs concentrations) with preterm delivery cases among women of Lucknow city (India). We performed a case-control study and a total of 60 mothers (n=31 full term and n=29 preterm deliveries) were recruited at a local nursing home of Lucknow, for the period of August 2005-February 2006. Subsequent to parturition, placental tissues from each participant were immediately collected and kept at -20 degrees C until PAHs analyses. Placental tissue PAHs concentrations were determined by HPLC, using a fluorescence detector. Mean+/-SD placental level (61.91+/-12.43ppb) of benzo(b)fluoranthene, a carcinogenic PAH, was found significantly elevated (p<0.05) among women with preterm delivery when compared with the level (23.84+/-7.01) in women having full-term deliveries. In the same way, non-carcinogenic fluoranthene level (325.91+/-45.14ppb) was also detected to be higher in the preterm delivery group compared to 208.6+/-21.93ppb level from the full-term delivery group of women. Additionally naphthalene, acenaphthylene, phenanthrene, anthracene, benzo(a)pyrene and dibenzo(a,h)anthracene levels in placental tissue were also found to be higher in the preterm delivery group of women but the difference did not reach statistically significant levels. This foremost study from India with modest samples size and limited statistical power does not show a substantial involvement of PAHs with preterm delivery, but higher concentrations of placental PAHs detected among preterm delivery group of women could show some possible association with these environmental toxicants. Further study with large sample size, controlled for confounders and great statistical power, is reasonable to elucidate the association of PAHs exposure with preterm delivery of women in India.

Assessment of association of exposure to polycyclic aromatic hydrocarbons with bronchial asthma and oxidative stress in children: A case control study

Background: Polycyclic aromatic hydrocarbons (PAH) originate from the incomplete combustion of organic matter and ambient air pollution by these is increasing. There is also an increase in the global prevalence of asthma, for which environmental pollution has been recognized as one of the important factors. Exposure to pollutants and other allergens induces chronic airway inflammation by generation of reactive oxygen species, causing oxidative stress. Therefore, the objective of the present study was to assess association, if any, between exposure to PAH and asthma as well as oxidative stress in children. Method: In this hospital-based case control study, cases of bronchial asthma aged 1–14 years and healthy matched controls were included. Oxidative stress was measured by assessing the levels of enzymes catalase, superoxide dismutase, malondialdehyde (MDA), and reduced glutathione (GSH). Results: Forty-two cases and 20 controls were enrolled. Mean blood level of phenanthrene, a PAH, was 63.11 ppb ± 115.62 and 4.20 ppb ± 10.68 ppb in cases and controls, respectively (P = 0.02). Mean blood levels of GSH was significantly lower in cases and controls (27.39 μg/ml ± 11.09 versus 47.39 g/ml ± 13.83; P-value = 0.001). Likewise, mean blood level of MDA in nanomole/ml was significantly higher in asthma as compared with controls (12.85 ± 5.40 versus 8.19 ± 5.16; P-value = 0.002), suggestive of increased oxidative stress. Conclusions: Because elevated blood level of phenanthrene is associated with bronchial asthma as well as with oxidative stress, measures to reduce exposure to PAH may possibly lead to reduced incidence and severity of bronchial asthma.

Monitoring of plasma butyrylcholinesterase activity and hematological parameters in pesticide sprayers.

To evaluate the health impact of spraying organophosphorus insecticides (OPs), 34 male sprayers in the mango belt of Malihabad, a small town located 27 km from Lucknow in North India was selected. Plasma butyryl cholinesterase (PBChE) and complete blood count were assessed among sprayers after spraying pesticides and the findings obtained were compared with those determined in a reference group (n = 18). The most common symptoms observed were burning sensation in the eyes (8.82%), itching/skin irritation (23.52%) and chest symptoms (32.35%) in the exposed workers. Plasma butyrylcholinesterase (PBChE) was significantly decreased in workers. The results indicated significant decrease in the mean value of hemoglobin, hematocrit and platelets count; however, significantly higher count of leukocytes was also observed in the exposed group (sprayers) compared to that observed in the control group (P < 0.05). Monitoring of PBChE in pesticide sprayers could be useful to predict and prevent health hazards of OPs.

Face mask application as a tool to diminish the particulate matter mediated heavy metal exposure among citizens of Lucknow, India.

Traffic related fine particulate emissions, enriched in metal contents, are directly linked to respiratory disorders in human subjects. In view of the growing traffic related emissions in India, the present study was undertaken to estimate the heavy metal exposure among non-occupationally exposed two vehicle riders of Lucknow City and related health effects via application of face masks (FMs) fitted with cellulose nitrate filters and measuring the peak respiratory flow rate (PEFR). Carefully selected 200 volunteers (asymptomatic n=154 and symptomatic n=46) were advised to use FMs during their deriving time for 30 days and PEFR test was conducted on each subject at the beginning, i.e. 0 day, and at end of the study period, i.e. 30 days. On completion of the prescribed study period, filters from the used FMs were collected, acid leached and analyzed for Fe, Mn, Cu, Zn, Pb, Ni, Cr and Cd. Asymptomatic and symptomatic subject groups were further divided into two age groups of 15-40 years and 41-68. Pb, Cu and Cd were significantly higher in lower age group (15-40) of symptomatic group and Cr was in asymptomatic group. Negative associations were observed between metals viz. Pb (r=-0.39, p<0.001), Cd (r=-0.26, p<0.001), Fe (r=-0.37, p<0.001), Mn (r=-0.15, p<0.05) and the lung functioning. 30 days PEFR of all subjects were higher by nearly 10% than 0 day in all 200 samples irrespective of age and symptomatic nature of the subject. The improvement could also be due to metals and other organic species, not analyzed herein. Nevertheless the results indicate that FM usage has a role to play for immediate, if not ultimate, improvement in public health and need further studies.