In many occupational settings, the ambient environment
is a sink of various contaminants that emerge from
point and nonpoint sources and causes direct exposure to
workers. Such exposures in petroleum-related occupations
usually result from routine transportation, distribution,
accidental spills, improper handling and use, and
leaching of petroleum hydrocarbons products; there are
also many other ways by which humans are exposed to
these chemicals [1]. Many of the aromatic organic
solvents, such as toluene, ethyl benzene, xylene, etc., are
common components of petroleum products, most of
which have already been confirmed as carcinogens, e.g.,
benzene [2e4]. Benzene is considered to be one of the
possible causes of morbidities among automobile
workshop mechanics as well as in automobile painters
[5]. Among many other environmental sources, benzene
mostly arises from fuel vapors and gasoline (range,
1.8e3.7%) and from solvents used for degreasing or as
diluents at work areas of automobile mechanics [6].
Most exposures to organic solvents occur during the
maintenance of various engine parts [7]. Such solvents,
after being absorbed into the intercellular fluid, may
enter main bloodstream and get distributed throughout
the body [8]. Benzene affects blood production by
affecting the bone marrow. In Korean industries, an
excessive risk of hematopoietic diseases because of
relatively high past exposure to benzene has been reported
[9]. Apart from direct occupational exposure,
nonoccupational population around chemical factories
and other occupational sites may also undergo indirect
exposure [10]. Thus, occupational exposure hematotoxicity
[11] and other blood disorders such as blood
cancer (leukemia), aplastic anemia, and dysplastic bone
marrow conditions are common results of exposure to
aromatics such as benzene [12], screening of which can
be done easily by complete blood counts.
Thousands of workers in Pakistan are routinely
exposed to such chemicals, but no such data are available
due to lack of proper reporting [13]. Even local
people who do not have any direct occupational exposure
to chemicals may get exposed to varying levels of
benzene from the ambient environment [14]. Exposure
studies are the most important steps toward identification
and prevention of multiple risks that vary with occupational categories and job responsibilities. Many
studies [15] have used demographic features such as
age, gender, body mass index (BMI), smoking status,
and consumption of certain types of contaminated food
in exposure assessments. It is necessary to keep these
features in focus while setting rules and regulations for
potential hazardous occupations, which can be helpful in
minimizing health risks. In developing countries such as
Pakistan, creating awareness among workers about
workplace chemicals and other related hazards should
also be given priority. There should be thorough hazard
assessments at a large scale to review occupational
safety conditions at the initial stage, and practical
measures should be taken to minimize them in future.
This study was planned to evaluate the effects of
continuous exposure to solvents, chemical contaminants,
and other confounding factors that may cause
functional changes in blood parameters. It may be
helpful in future for suggesting the most significant
priorities in the light of research outcomes, to minimize
workplace- and occupation-related health risks, and to
ensure safety to workers’ health.