Role of environmental pollutants in liver physiology: special references to peoples living in the oil drilling sites of Assam.

Tapan Dey,Moonmee Bharadwaz,Pranab Kumar Baruah,Jatin Kalita,Manoj Kalita,Balagopalan Unni,Kabita Gogoi,Thaneswar Bora,Dibyajyoti Ozah,Munmi Kalita

doi:10.1371/journal.pone.0123370

Abstract

The populations residing near polluted sites are more prone to various types of diseases. The important causes of air pollution are the suspended particulate matter, respirable suspended particulate matter, sulfur dioxide and nitrogen dioxide. As limited information is available enumerating the effect of these pollutants on liver physiology of the population living near the polluted sites; in the present study, we tried to investigate their effect on liver of the population residing near the oil drilling sites since birth. In this study, a randomly selected 105 subjects (46 subjects from oil drilling site and 61 subjects from control site) aged above 30 years were taken under consideration. The particulate matter as well as the gaseous pollutants, sulfur dioxide and nitrogen dioxide, were analyzed through a respirable dust sampler. The level of alkaline phosphatase, alanine transaminase and aspartate transaminase enzymes in serum were measured by spectrophotometer. The generalized regression model studies suggests a higher concentration of respirable suspended particulate matter, suspended particulate matter and nitrogen dioxide lowers the alkaline phosphatase level (p<0.0001) by 3.5 times (95% CI 3.1-3.9), 1.5 times (95% CI 1.4 - 1.6) and 12 times (95% CI 10.74 -13.804), respectively in the exposed group. The higher concentration of respirable suspended particulate matter and nitrogen dioxide in air was associated with increase in alanine transaminase level (p<0.0001) by 0.8 times (95% CI 0.589-1.049) and by 2.8 times (95% CI 2.067-3.681) respectively in the exposed group. The increase in nitrogen dioxide level was also associated with increase in aspartate transaminase level (p<0.0001) by 2.5 times (95% CI 1.862 – 3.313) in the exposed group as compared to control group. Thus, the study reveals that long-term exposure to the environmental pollutants may lead to liver abnormality or injury of populations living in polluted sites.

Highlights

Oil Spillage has always been a prominent reason for causing air pollution around the oil drilling sites
Air sample analysis was done throughout a year both in oil drilling sites and in the control sites for all the variables such as respirable suspended particulate matter, suspended particulate matter, SO2 and NO2
Both the alanine transaminase (ALT) and aspartate transaminase (AST) are released from damaged hepatocytes into the blood after hepatocellular injury or death leading to their higher concentration in blood [19]

Summary

Introduction

Oil Spillage has always been a prominent reason for causing air pollution around the oil drilling sites. Many epidemiological studies have suggested the environmental pollutants due to oil spillage play a major role in developing various kinds of respiratory problems such as chronic obstructive pulmonary disease (COPD), asthma and other related diseases [1]. Few epidemiological studies showed the impact of large marine oil spills affecting the health of cleanup operators [1, 4]. They studied the persistence of functional and biological respiratory health effects after 6 years of completion of the cleanup work and found no clear differences between highly exposed and moderately exposed cleanup workers [4]. It is reported that, the higher concentrations of sulphur dioxide (SO2) and nitrogen dioxide (NO2) pollutants were significantly related to symptoms of respiratory ailments in children [5]

Methods

Results

Conclusion