Content uploaded by Ademola Adeyeye
Author content
All content in this area was uploaded by Ademola Adeyeye on Dec 11, 2021
Content may be subject to copyright.
Occupational Lead Exposure in Printing Presses: An Analytical Approach.
S.A. Oke, M.Sc.1*, T.E. Phillips1, A. Kolawole, M.Sc.2, C.E. Ofiabulu, M.Sc.2,
and D.A. Adeyeye, M.Sc.2
1Department of Mechanical Engineering, University of Lagos, Nigeria.
2Department of Industrial and Production Engineering, University of Ibadan, Nigeria.
*E-mail: sa_oke@yahoo.com
ABSTRACT
Lead absorption poses a great threat to the health
of workers in printing presses where commercial
publishing is done. A case example is the
commercial printing operations in Lagos, Nigeria.
Since regular exposure to lead dusts could result
in lead poisoning, complications that could cause
death of victims, monitoring and controlling lead
absorption of operators is essential for the
maintenance of workers’ health and for the
avoidance of the risk of incurring heavy losses
due to litigation. The purpose of this paper is to
model the process, rate, and quantity of lead
absorption in operators of printing presses.
Measurements of lead absorption are made and
compared to standards in individuals for control
purposes. Two approaches are used. The first
shows the risk of being poisoned by lead. The
second approach relates lead poisoning to the
rates of intake of lead into the body and its
elimination out of the body. This model viewed the
absorption of lead as a cycle and applied the
continuity equation to this cycle.
(Keywords: printing press, small enterprises, daily
intake, elimination rate, blood lead, lead, Pb, poisoning,
occupational health, Nigeria)
INTRODUCTION
In Nigeria, printing enterprises share similar
characteristics with those in other developing
countries in Africa, Asia, and the rest of the world.
Usually, many printing businesses occur on a
small-scale, are geographically scattered, and
located across major commercial cities. For
example, in Lagos Nigeria, a large concentration
of these small-scale printing businesses are
located in the areas of Somolu, Agege, and
Mushin which are short distances to the
concentration of multinationals and local
industries which have their headquarters in
Lagos. Such companies require printing services
for the production of several documents both for
daily transaction and non-frequent activities.
Some of these services include advertisement
and product packaging. Thus, printing is lucrative
business in many of these commercial nerve
centers of Nigeria. Unfortunately, a large number
of small/medium-scale enterprises (SMEs) still
engage in the traditional processing activities that
have long been identified as occupationally
hazardous. Of particular concern to the current
investigators is the improper usage and handling
of poisonous substances and materials such as
lead, which are used for printing purposes.
In these SMEs, operators usually inhale some of
these substances in quantities that may be
hazardous to human health. In other situations
individuals may swallow such substances
through food consumed in the printing
environment (Twyman, 1970). Despite the
seriousness of these problems, it appears that
little documentation exists on lead exposure
research, in particular, quantifying the amount of
lead absorbed into the body by operators in
printing presses. If such valuable information are
provided, occupational health inspectors would
be able to effectively monitor and control such
unattractive incidences. This work is motivated to
contribute to the current discourse on lead
absorption in printing presses. In particular, a
mathematical model is presented that would
guide in evaluating particular amount that are
consumed by the operator (Basmadjian, 1999;
Krishna-Murthy et al., 1988).
THE PRINTING PRESS AND LEAD
POISONING
Printing, the age-old process of producing texts
and images on paper using a printing press, is an
essential part of publishing that utilizes lead
The Pacific Journal of Science and Technology –263–
http://www.akamaiuniversity.us/PJST.htm Volume 9. Number 1. May-June 2008 (Spring)
which proved to be more suitable for printing than
clay, wooden, or bronze (Steinberg, 1996).
Printing is one of the line of businesses that have
traditionally had a high occupational exposure to
health hazards (Cherry et al., 2001). The lead
used for printing is made from an alloy of lead, tin,
and antimony. It is the lead contained in this alloy
that is of interest in this paper (Blaskette and
Boxal, 2001; Sinha et al., 1993; Murthy et al.,
1990; Krishna-Murthy and Sridhara Rama Rao,
1992).
The initiative of measuring the lead absorption in
operators, and relating lead poisoning to the rates
of intake of lead into the body and its elimination
out of the body is motivated by reactions from all
the stakeholders in printing services. Several
customers have shown concern for the risk that
the operator face by having direct contact with
lead plates without any protective devices. First,
lead is a highly toxic substance and poisonous
metal that can damage the nervous system and
cause blood and brain disorders. Long-term
exposure to lead or its salts can cause neuropathy
and colic-like abdominal pains. Lead has also
been linked with dementia and schizophrenia
(NHMRC, 2006). Second, most operators in
printing presses work around the lead plates all
day, and are exposed to lead dust from the plates
which they can take-in in several ways. This may
be through normal hand-to-mouth contact and
inhalation, where lead dusts find its way into the
nostrils and hence is taken into the body. Lead
poisoning could occur through eating lead chips.
The symptoms of lead poisoning include
neurological problems such as reduced
intelligence quotient (IQ), nausea, abdominal
pains, irritability, insomnia, excess lethargy or
hyperactivity, headaches, and in extreme cases,
seizure and coma. There are also associated
gastrointestinal problems such as constipation,
vomiting, poor appetite, weight loss, kidney
problems, and reproductive problems. Health
inspectors have shown concern and usually
instruct printing press owners not to keep an
operator on the job continuously. The reaction of
the investor often is fear of the liability that may be
incurred as a result of possible operator’s death or
critical illness. Thus, all these pointers are strong
indicators to the need to embark on the current
study.
A brief review of relevant literature is hereby
given. Cherry, et al. (2001) investigate
occupational exposure/infertility links in patients.
It was concluded that exposure to organic
solvents is common both at work and in
recreational pursuits and that efforts should be
made to identify the compounds hazardous to
male fertility, and if the risk is confirmed, to
regulate their use.
Rajah and Ahuja (1995, 1996) in two series of
studies investigated lead exposures in printing
press workers. In the first attempt, Rajah and
Ahuja (1995) evaluated the geneotoxicity of a
combination exposure of lead and smoking in
workers from the printing industry and also
examined the possible interactions between the
two agents. The study shows that lead-exposed
individuals had a significant increase in the
frequency of sister chromatid changes. Further,
double-exposure to smoking and lead inhibited
mitosis.
In a second study by Rajah and Ahuja (1996), the
authors evaluate the genotoxicity of a double-
exposure to alcohol and lead in subjects from the
printing industry, and the possible interaction
between the two agents. Alcohol consumers had
a significant increase in the frequency of sister
chromatid exchanges (SCEs) compared to the
controls. Though there was an increase in the
frequency of chromosome aberrations and SCEs
in individuals exposed to lead, it was not
significant. Statistical analysis did not reveal an
interaction between alcohol and lead in either
assay.
Murthy, et al. (1990) report a morbidity survey
relating to lead toxicity among workers engaged
in letter press printing work using techniques of
clinical examination of workers and estimation of
blood lead and urine lead in their blood and urine
samples. The results indicate higher blood and
urine lead levels recorded among study group as
compared to the age and experience matched
control group.
From the limited studies on lead absorption in
printing press workers, it seems that analytical
approaches in the measurement of blood lead
levels have not been explored, particularly in the
developing country, Nigeria. This is necessary
since without accurate and reproducible
measurements, it is difficult to monitor and
control the blood lead level in printing workers.
The need to close this important gap has
motivated the current study.
The Pacific Journal of Science and Technology –264–
http://www.akamaiuniversity.us/PJST.htm Volume 9. Number 1. May-June 2008 (Spring)
The above equation is a normal reaction where u
units of Ca+ combine with υ units of PR to
produce w units of combined CaPR. Now,
consider an abnormal reaction, where lead is
present in the blood. This lead has the tendency
to mimic calcium, and it reacts with the protein to
produce a slightly different compound. Assume
that this chemical reaction is as shown below:
The sections that follow are divided into:
methodology, discussion, and conclusion. The
methodology discusses two approaches utilized in
solving the blood level monitoring problem. These
approaches are consequently complemented with
case study illustrations that verify the application
of the developed formulae in the early parts of
Methodologies I and II. This approach of
methodology/case study is taken in order to
ensure an adequate flow of thoughts presented in
the work. The section on methodology is then
followed by discussion, which explains some
issues, and the implications of the approaches
presented in practice. The paper then closes with
concluding remarks.
2uCa+ + υPR + γPb2+ wCa2PbPR (3)
METHODOLOGY
This section shows how the study was
undertaken, the variables that were assessed,
and the evaluation techniques. Basically, two
techniques are employed in order to define the
solutions to the problems formulated. The first
technique, referred to as Methodology I,
investigates into production of enzymes from food
eaten. In the presence of lead, the lead substance
mimics the enzyme production process to produce
a different compound thus creating a problem
(Figure 1).
The second technique, termed Methodology II,
models the absorption process as a cycle in order
to determine the concentration of lead in the body
(Figure 2). These techniques are now discussed
in detail.
Methodology I: Production of enzymes
In order to illustrate this methodology, consider a
protein, say PR, which is responsible for the
production of an enzyme, EZ, which is necessary
for the division of brain cells. Now, assume that
this protein reacts normally with calcium (Ca) from
food eaten in the following reaction:
Ca Ca+2 + 2e- (1)
uCa+ + υPR wCaPR (2)
where u, υ and w are numeric constants.
The symbols u, υ and w are numerical constants.
However, lead (Pb) undergoes the ionic reaction
shown as:
Pb Pb2+ + 2e- (4)
Now, if the lead in Ca2PbPR reacts with oxygen
in the blood, it could form a strong oxidant, lead
oxide (PbO2), which is very toxic and affects the
nervous system. This is the pollutant that enters
the blood stream of the printing press operator.
The reaction that occurs is as follows:
wCa2PbPR + 2wO2- w(CaPR)2- + wPbO2 (5)
Now, if we assume that the original compound
formed by calcium (Ca) and protein, PR(CaPR),
as shown in Equation (2) undergoes a series of
complex chemical reactions to form enzyme, EZ,
with certain DNA characteristics (these complex
DNA characteristics are left to chemists and
biologists for further analysis), the presence of
lead in this compound alters these DNA
characteristics, hence leading to a totally different
and harmful enzyme.
From Equation (5), the compound Ca2PR2- is
anionic instead of the neutral compound, CaPR,
which is should have been originally.
From the foregoing, two possible causes of
poisoning have been established. These are: (i)
the toxic oxide, wPbO2, and (ii) the anion
w(Ca2PR)2-.
This shows that depending on the value of the
above constant, w, there will either be a large
number of lead oxide molecules and (Ca2PR)2-
ions in the brain. This value, w, will determine
the severity of the damage that will be done in
the brain. The value of w in turn depends on the
values of u, υ, and γ as shown in Equation (3)
i.e.:
2uCa+ + υPR + γPb2+ wCa2PbPR (3)
The Pacific Journal of Science and Technology –265–
http://www.akamaiuniversity.us/PJST.htm Volume 9. Number 1. May-June 2008 (Spring)
Contact through skin Contact through mouth
Absorbed by digestion
Absorbed into
the blood s
y
ste
m
Reaction with
p
rotein P
R
Calcium
Formation of CaPbPR
Formation of lead oxide
(
PbO
2
)
di
g
estion Formation of (Ca2PR)2- ion
digestion
Brain cells
Absorbed through
the skin digestion
Lead Dust
Figure 1: Movement of Lead through the Body, and the Reactions Between Lead and Other
Substances in the Body.
C
l
e
aran
ce
Elimination
(storage in dormant form in the
bones)
Injestion/
exposure to lead
Infusion
Figure 2: Cyclic Consideration of Lead Absorption Process in Operator.
The Pacific Journal of Science and Technology –266–
http://www.akamaiuniversity.us/PJST.htm Volume 9. Number 1. May-June 2008 (Spring)
From this Equation (3), it is observed that if the
value of u is larger than the value of γ, more
molecules of CaPR are formed than Ca2PbPR.
Also, depending on the ratio of u to γ, the CaPR
molecules could either nullify the effect of the
Ca2PbPR or their presence could be negligible as
compared to that of Ca2PbPR molecules.
It is important to verify the equations in a real life
case study in order to demonstrate the practical
application of the concept proposed here. Case
study 1 shown below is a good illustration of the
ideas presented above.
Case Study 1
Consider two young city and guide (C and G)
professionally-qualified operators – Mr. X and
Miss Y – who work for an organization named
Nigerian Printing Press (NPP). This small-scale
organization employs 10 workers and is located in
the business district of Somolu Local Government,
Somolu, Lagos. These operators work on two
different printing presses. On a certain day, they
are both exposed to the same amount of lead
dust. However, as a preventive measure to
inhaling lead, Miss Y was careful to wash her
hands before eating during her lunch break.
Unfortunately, Mr. X did not since no stringent
conditions or rules were in place in the
organization concerning personal hygiene of
workers during and after work.
Miss Y, also took a bath before going home that
evening at the enterprise’s bathroom, which is in
the same compound. It is observed that due to
precautions taken over time by Miss Y, the value
of γ in her blood lead was 2, While Mr. X was 6.
Now, assume that both Mr. X and Miss Y ate a
meal containing vegetables in the canteen. Mr. X,
being a fat man, ate a larger portion of the food
than Miss Y, and hence, the value of u in his meal
was 4 while that of Miss Y was 2.
With the above data, the equations developed
previously could be used to find out which of Mr. X
or miss Y is in greater danger of lead poisoning.
For Mr. X, u = 4, and γ = 6. These values could
be inserted into Equation (6), as shown below:
24 Ca+ + 2PR + 6Pb2+ wCa2PbPR (6)
Here, it is assumed that the value of υ in an
average person’s body protein is 2. However, by
balancing Equation (6) the following is obtained:
24Ca+ + 12PR + 12Pb 12(Ca2PbPR) (7)
It is obvious that from Equation (7), the value of w
is 12. This means that 12 molecules of PbO2 and
(Ca2PR)2- will be formed. Since for Mr. X, the
value of γ is larger than that of u, more molecules
of Ca2PbPR are formed than those of CaPR.
The ratio of u to γ is 4:6, (i.e. 2:3), implying that
Ca2PbPR molecules will nullify the effect of
CaPR in his blood.
For Miss Y, u = 2, γ = 2. Thus, Equation (3)
becomes:
2(2) Ca+ + 2PR + 2Pb2+ w Ca2PbPR (8)
Thus, by balancing Equation (8), the following are
obtained:
4Ca+ + 2PR + 2Pb2+ 2Ca2PbPR (9)
From equation (7), the value of w is just 2 as
compared with 12 of Mr. X. This implies that just
2 molecules of PbO2 and (Ca2PR)2- will be
formed in her blood. Her susceptibility to lead
poisoning is much lower than that of Mr. X. Also,
the ratio of u to γ in her blood is 2:2, which gives
1. Despite the fact that the value of w is very low,
this ratio is not attractive for a safe level of lead in
the blood. It gives a 50 to 50 chance of being in
danger or of being healthy.
Methodology II: Measurement and Cyclic
Consideration of Lead Absorption Process
In order to understand Methodology II, it is
necessary to first illustrate the movement of lead
through the body and the reactions that go on
between lead and other substances in the body.
A further understanding of Methodology II is
aided by considering a simplified cyclic
consideration of the lead absorption process.
Final information that would further aid
understanding of Methodology II is the definition
of a set of terms in measurement that guides the
measurement activity of Methodology II.
The Pacific Journal of Science and Technology –267–
http://www.akamaiuniversity.us/PJST.htm Volume 9. Number 1. May-June 2008 (Spring)
From the basic principles of inorganic chemistry,
it is known that the concentration of a substance
may change with time. So, the starting point in
the development of equations for Methodology II
is to plot a graph of concentration (C) of lead in
the body against time. This gives the graph in
Figure 3.
Definition of terms
The following are international standards of
measurement of lead in the body (Table 1):
Table 1: Definition of Terms.
From Figure 3, it is understandable that the
concentration of lead either in the environment or
body against time changes results in rate
measurement. Thus, mathematically, it could be
stated that:
1. Acceptable Daily Intake (ADI): ADI is a
measure of the amount of a specific
substance, usually in food or drink that
can be ingested without appreciable
health risk (WHO, 2006).
2. Blood Lead Level (BLL): One measure of
lead in the body is the blood lead level
measured in micrograms of lead per
deciliter of blood (µg/dL) (CDCP, 2006).
3. Ingestion: the process of taking in the
lead into the body.
4. Clearance: Here, it is assumed that the
blood has reached a near uniform level
that exposure has ceased.
5. Infusion: This is a continuous influx of the
lead.
6. Elimination: This is the assumption that
some of the lead leaves the body.
Rate of lead in – Rate of lead out
= Rate of change in lead content (10)
This means that the rate of absorption of lead
into the human body minus the rate at which lead
is lost from the body to the environment gives the
actual rate at which lead is retained in the body.
From the graph, it is observed that time changes
from 0 (origin) to t. Now, starting from time t = 0,
equation (10) can be interpreted thus:
C
t Time (hours)
Concentration (µg/dL)
Figure 3: Concentration of Lead in Blood versus Changes in Time.
The Pacific Journal of Science and Technology –268–
http://www.akamaiuniversity.us/PJST.htm Volume 9. Number 1. May-June 2008 (Spring)
Qdt
dc
V CVk - e= (11)
where Ke is the rate constant of elimination
V is the volume of distribution
K
eC is the rate of elimination
Q is the flow rate of lead in the body
By separating the variables, integrating them, and
obtaining the value of the elimination rate
constant, Ke, the following is obtained:
()
t2.303 logC
K- e
×
= (12)
Now, applying the flow rate concept to the lead
absorption process, it is noted that the flow rate is
the rate of change of the concentration. Thus, Q
= dt
dc is substituted in Equation (11) to yield:
dt
dc = vCVk- e; and Q = -KeC (13)
Equation (13) expresses the rate of passage of
lead into the blood through the walls of the blood
vessels. This process is diffusive.
Now, taking the body as an open thermodynamic
system and the blood as the working fluid,
applying the continuity equation (Alcock, 2001):
V
A
m
υ
=
& (14)
where
m
& is the mass flow rate of lead
υ is the velocity of lead in the blood
A is the area of the blood vessels
V is the volume of distribution of lead.
The rate equation in (10) could become:
, thus, Q K - m e=
&
Q
t2.303 logC
-
V
A=
×
υ
(15)
From Equation (15), it becomes clear that the flow
of lead in the body would depend on the mass
flow rate of lead and the rate of elimination of lead
from the body. However, the mass flow rate
would also depend on the velocity of blood, the
area of blood vessels, and the volume of lead
(i.e. the volume of the exposure to lead, namely if
a person works for x hours in a day, and is
exposed to y µg of lead per day).
However, the maximum level of blood lead is
10µg/dL of blood, according to the health
authorities. This implies that:
g/dL01
V
A
µ
υ
≤ (16)
Equation (16) gives the acceptable daily intake of
lead (ADI).
Case Study 2
This case illustrates a measurement activity in
which the blood lead level (BLL) of a particular
worker is measured and compared with the
standard set to determine if it is below standard
or not. The employee concerned works for the
Ibadan Printing Press, and is named Miss O.O.
Health workers from the World Health
Organization (WHO) paid a visit to the company,
and in a random selection, Miss O.O. was picked
along with 49 other employees so as to carry out
a survey on lead absorption and poisoning. On
this particular day, her blood samples were taken
over a 15-hour period and the following data was
obtained (Table 2).
Table 2: Blood Lead Level Measurement over a
15-hour Period.
Time (hours) C (µg/dL)
3 87.5
6 68.4
9 53.3
12 28.1
15 20.6
The table shows the subject’s blood lead
concentrations in intervals of 3 hours, starting
from 3rd hour to the 15th hour. In utilizing this
data, the analyst should recall Equation (12), and
substitute the values of C and t at a particular
point to obtain a value for Ke. Based on this, the
value of Ke and C are also substituted into
Equation (13). The value of Q obtained is now
substituted into Equation (15) in order to find out
The Pacific Journal of Science and Technology –269–
http://www.akamaiuniversity.us/PJST.htm Volume 9. Number 1. May-June 2008 (Spring)
the equivalent value of V
A
υ
. This particular value
of V
A
υ
is the measure that is compared against
standard to decide if the BLL is less than, equal
to, or greater than the set standard by the
monitoring agencies. As an illustrative example,
the values of BLL after 12 hours is utilized. First,
Equation (12) is recalled, and the value of Ke
calculated as:
()()
0.278
12 2.303 28.1 log
t2.303 logC
Ke=
×
=
×
=− .
Substituting the value of –Ke and C into Equation
(13) gives: Q = 0.278 x 28.1 = 7.81.
Now, by substituting the values of Q and –Ke into
Equation (15), the following is obtained:
V
A
υ
- 0.278 = 7.81,
which gives V
A
υ
= 7.81 + 0.278 = 8.088.
The value of 8.088µg obtained is then substituted
in Equation (16) in comparison with the value on
the right hand side of the expression. In this
particular example, substitution gives 8.088 <
10µg. This condition is satisfied as the calculated
value of 8.088µg is less than the standard of
10µg. It may therefore be concluded that at the
instant of measurement (i.e. 12 hours), Miss
O.O.’s Acceptable Daily Intake (ADI) has not been
exceeded and her blood lead level is below the
set standard. Hence, Miss O.O.’s condition is
acceptable to the health authorities. However, it
needs to be controlled.
DISCUSSION OF RESULTS
From Equation (3), it is obvious that the value of u
has to be higher than that of γ for one to have an
acceptable blood lead level. In the first case
study, running Mr. X’s data through the model
showed that he was at a risk of being poisoned by
lead. Miss Y. on the other hand was discovered
not to be as safe as it apparently seemed.
The second model was able to relate lead
poisoning to the rates of intake and elimination of
lead into and out of the body. This model took the
absorption of lead as a cycle and applied the
continuity equation to this cycle.
CONCLUSION
This paper addresses matters that relates to
organizational safety, health, and the
environment. Consequently, safety and health
professionals, governments, and all the
stakeholders in the printing business, should
favorably view this paper. The paper is an
attempt at addressing the lead absorption
problem that poses a great threat to the health of
workers in printing presses. In particular, the
paper models the process, rate, and quantity of
lead absorption in operators of printing presses.
The second part of the paper relates lead
poisoning to the rates of intake of lead into the
body and its elimination out of the body. These
efforts are to avoid associated lead poisoning
gastrointestinal problems such as weight loss,
kidney problems, and reproductive impairment.
The methodology employed shows how the study
was undertaken and assesses variables that
relate to acceptable daily intake, blood lead level,
and elimination rates. Basically, whichever way
the examination is approached, it still remains a
fact that lead absorption is a hazard to health and
needs to be curtailed.
This research has implications and
consequences for small-scale printing
enterprises. First, in view of the small size of the
printing organizations studied, adequate care
must be taken to guard against direct contact or
exposure of operators to lead. As such, lead
plates must be handled with gloves, and the
environment well ventilated. Management must
ensure strict adherence to this instruction with
adequate penalties imposed on defaulters.
Continuous training and enlightenment on lead-
handling techniques should be carried out. The
management should be aware that the liability
cost incurred for an operator whose health is
failing as a result of lead poisoning is higher than
the preventive cost incurred on enlightenment
and house cleansing/environmental activities.
Since it is unlawful to retain an operator on the
job that exposes him to lead for a long time, skill
transfer programs should be utilized for job
continuity in the printing organization. It should
be noted that regular medical checks to observe
the possible level of lead in the blood and the
application of the models developed here are
essential.
The Pacific Journal of Science and Technology –270–
http://www.akamaiuniversity.us/PJST.htm Volume 9. Number 1. May-June 2008 (Spring)
REFERENCES
1. Alcock, C.B. 2001. Thermochemical Processes:
Principles and Modes. Butterworth – Heinemann:
London, UK.
2. Basmadjian, D. 1999. The Art of Modelling in
Science and Engineering. Chapman & Hall/CRC:
New York, NY. 314 – 324.
3. Blaskette, D.R. and Boxal, D. 2001 Lead and its
Alloys. Ellis Horwood: London, UK. 120 – 159.
4. Centers for Disease Control and Prevention
(CDCP). 2006. http://www.cdc.gov/. Accessed
22/12/06.
5. Cherry, N., Labrèche, F., Collins, J., and Tulandi,
T. 2001. “Occupational Exposure to Solvents and
Male Infertility. Occupational Environment and
Medicine. 58:635-640.
6. Krishna-Murthy, V., Keshavamurthy, S.R.,
Ramachandran, C.R., and Rajmohan, H.R. 1988.
“An Enquiry into Lead Absorption in a Battery
Manufacturing unit at Bangalore, India”. Journal of
Industrial Medicine. 34(4):145-149.
7. Krishna-Murthy V., Sridhara-Rama-Rao B.S., 1992,
Blood lead concentration of traffic personnel in the
city of Bangalore, India, Asian Environment, Vol.14,
No. II, pp. 3-13.
8. Murthy, V.K., Murthy, D.P.H., Chandrashekhar,
B.G., Rajan, B.K., and Rajmohan, H.R. 1990.
“Survey of Lead Exposure Among Printing Press
Workers in Banglore, India”. Journal of Industrial
Medicine. 36(1):32-51.
9. National Health and Medical Research Council
(NHMRC). 2006. http://www.nhmrc.gov.au/.
Accessed 22/12/06.
10. Rajah, T.T. and Ahuja, Y.R. 1996. “In Vivo
Genotoxicity of Alcohol Consumption and Lead
Exposure in Printing Press Workers”. Alcohol.
13(1):65-68.
11. Rajah, T.T. and Ahuja, Y.R. 1995. “In Vivo
Genotoxic Effects of Smoking and Occupational
Lead Exposure in Printing Press Workers”.
Toxicology Letters. 76(1):71-75.
12. Sinha, S.P., Shelly, V.S., Meenakshi, S.S.,
and Srivastava, M.M. 1993. “Neurotoxic Effects of
Lead Exposure Among Printing Press Workers”.
Bulletin of Environmental Contamination and
Toxicology. 51(4):490 – 493.
13. Steinberg, S.H. 1996. 500 Years of Printing. Oak
Knoll Press: London, UK.
14. Twyman, M. 1970. The British Library Guide to
Printing: History and Techniques. Butterworth-
Heinemann: London, UK. 171 – 181.
15. World Health Organization (WHO). 2006.
Guidelines for Food Quality Control, Vol. 1.
http://www.inchem.org/documents/jecfa/jecmono/v
06je31.htm. Accessed 22/12/06.
ABOUT THE AUTHORS
S.A. Oke graduated in Industrial Engineering
from the University of Ibadan, Nigeria with a
Bachelor and Master's degrees in 1989 and
1992, respectively. He worked for the IDM
Services Limited as a consultant. Mr. Oke
lectures in the Department of Mechanical
Engineering, University of Lagos . He has
reviewed papers for several international
journals.
T.E. Philips is an Undergraduate student in
Mechanical Engineering, University of Lagos.
Occupational hygiene is one of her interests.
A. Kolawole earned a B.Sc. and M.Sc. in
Industrial Engineering, University of Ibadan. He is
currently a Doctoral candidate in Industrial
Engineering. His research interests include
occupational hygiene and ergonomics, among
others.
C.E. Ofiabulu has a B.Eng. (Oweri) and M.Sc.
(Ibadan), and currently is a Ph.D. candidate in
Industrial Engineering, University of Ibadan. He
teaches in the department as well.
D.A. Adeyeye has a B.Sc. (Ife) and M.Sc.
(Ibadan). He is currently a Ph.D. student of the
Department of Industrial Engineering, University
of Ibadan. Adeyeye teaches in the same
department.
SUGGESTED CITATION
Oke, S.A., T.E. Phillips, A. Kolawole, C.E.
Ofibulu, and D.A. Adeyeye. 2008. “Occupational
Lead Exposure in Printing Presses: An Analytical
Approach”. Pacific Journal of Science and
Technology. 9(1):263-271.
Pacific Journal of Science and Technology
The Pacific Journal of Science and Technology –271–
http://www.akamaiuniversity.us/PJST.htm Volume 9. Number 1. May-June 2008 (Spring)
