in Iron Foundries and Automobile Workshops at Khartoum City-Sudan RIYADH ABD ALSALAM ALI ...

210 Pages·2012·5.18 MB·English

ASSESSMENT OF EXPOSURE TO OCCUPATIONAL AND NON-
OCCUPATIONAL POLLUTION WITH SOME HEAVY METALS
in Iron Foundries and Automobile Workshops at Khartoum City-Sudan

By
RIYADH ABD ALSALAM ALI AMEER

B. Sc. Hons (Env. Science & Natural Resources) University of Gezira 1998 
M. Sc. (Env. Science) University of Khartoum 2005 

A Thesis Submitted for The Degree of Doctor of Philosophy (Ph.D.)
in Environmental Science
To
Graduate College
University Of Khartoum

Supervisor
Professor. Muna Mahjoub Mohamed

2011
In The Name of Allah
DEDICATION

To my Teachers;

To my large Family;

To my wife and children,

Sam & Sama
ACKNOWLEDGEMENTS
I am very much thankful and highly obliged to my supervisor, Professor. Muna Mahjoub
Mohamed, for her advises guidance and intellectual supervision. She made it possible to
accomplish this study.
I owe many thanks to Engineer. Sitt Nour Hassan Mohammed (Head of Industrial Hygiene
Department, Federal Occupational Health Administration, Khartoum), for her great help,
continuous guidance, technical support, and permission to use the occupational health
laboratory for preparation of samples and providing measuring tools at the research field.
She has shown an incredible amount of patience with me during this long process especially,
in coordination with the appropriate laboratories for samples analysis.
I sincerely thank Dr. Adam Alshamiri (Associate Professor, Taiz University, Yemen), who
has been a mentor to me since many years ago and helped me to access online scientific
papers from many famous journals. Thanks are also extended to the environmental and
constructional laboratory staff, especially Mrs. Solafa, Selma and inass; and also my
thanks to Mr. Ismail of National Health Laboratories for their assistance in analyzing
samples. Also wish to express my thanks to Mr. Mohamed Sam and Mr. Said qaid for their
assistance in collecting samples.
My thanks to the workers and administrative staff of Khartoum central foundry and of the
auto-workshops, for their hospitable reception and cooperation during this work.

  II
ABSTRACT
Iron foundries and automobile workshops can expose workers to
moderate or low concentrations of heavy metals (as Pb, Cd, Cr, Mn, Cu,
and Fe). These metals can also be released into the environment
surrounding the industrial plants and affect the general population living
near them. The study mainly aimed to determine whether exposure to
heavy metals studied were higher in the occupationally exposed workers
at the Khartoum central foundry and the auto-workshops (located at the
old industrial area, south of Khartoum centre, ≈3 Km) than in subjects not
exposed to occupational working environment and living near industrial
area (Alremila district)
A total of 30 workers at the Khartoum central foundry (workers group A)
and 34 workers at the auto-workshops (workers group B) with possible
exposure to heavy metals ; and two subject groups (general population)
consisting of 14 subjects living near the industrial area (subjects group
C), and 20 subjects living at about 3 Km away (subjects group D), were
examined. A questionnaire was administered to obtain information on
personal, life habits (smoking, tobacco chewing, alcohol), and work
characteristics; types of risks exposed to; use of safety precautions; and
health complaints. The four groups were matched for age and
socioeconomic status. The metals concentrations were studied in air and
fingernail. Lung function was also examined.
The results showed that metals Pb, Cr, Mn contents in nails was
significantly higher (p<0.05) in occupationally exposed workers (W.G)
than the non-occupationally exposed subjects (S.G). Similar FN-Cd levels
were observed in both of W.G and S.G. However, FN-Cd of S.G-C was
significantly higher (p<0.05) as compared with S.G-D or even W.G-B.
  III
Conversely, concentrations of FN-Cu and FN-Fe were lower in the
workers than in the subjects (p<0.05, p>0.05 respectively).
Mean nail Pb and Cd levels in the worker and subject groups were higher
than the normal range. Whereas the mean nail level of the remaining
metals (Mn, Cr, Cu and Fe) were within the normal range in all studied
groups except Cu level which was lower from the normal range in the
workers. There was high prevalence of ill health complaints or symptoms
among the workers especially in W.G-A. The complaints included pain
muscles and joints chronic headache, dizziness, cough, chest pain, poor
co-ordination, depression, insomnia, and skin irritation. Air samples
obtained from the workplace environment were high for some Pb, Cd and
sometimes exceeded the environmental threshold limits.
Lung symptoms showed moderate and severe restrictive/or obstructive
abnormality which was highest in W.G-A (20%), followed by W.G-B
(10%), without similar cases detected in subject groups. However, the
latter groups had more cases of mild restrictive abnormalities while about
9% of S.G-D showed mild obstructive abnormalities. It was revealed that
the recommended precautionary procedures concerning working in metal-
polluted environment were not applied or made available. It is concluded
that workers were exposed to high level of heavy metals especially the
toxic metals Pb and Cd and lack the recommended precautionary
procedures which made their health and safety at high risk as reflected by
metal toxicity or other occupational illnesses.

  IV
ﺔﺣوﺮﻃﻷا ﺔﺻﻼﺧ
تﺎﻳﻮﺘﺴﻣ ﻰﻟإ تﺎﺒآﺮﻤﻟا حﻼﺻإ شرو لﺎﻤﻋو ﺐﻠﺼﻟاو ﺪﻳﺪﺤﻟا ﻚﺑﺎﺴﻣ ﻲﻓ لﺎﻤﻌﻟا ضﺮﻌﺘﻳ
ﺞﺘﻨﺗُ ﺎﻣ ةدﺎﻋ ندﺎﻌﻤﻟا ﻩﺬه ، ( Fe و Cu ،Mn ،Cr ،Cd ،Pb ﻞﺜﻣ) ﺔﻠﻴﻘﺜﻟا ندﺎﻌﻤﻟا ﻦﻣ ﺔﻄﺳﻮﺘﻣ
؛ةروﺎﺠﻤﻟا ﻦآﺎﻣﻷاو ﺔﻴﻠﺧاﺪﻟا ﺔﺌﻴﺒﻟا ﻲﻓ ﺎهرﺎﺸﺘﻧا ﻢﺘﻳ ﺎﻣ ﺎًﺒﻟﺎﻏ ﻲﺘﻟاو ﺔﻴﻋﺎﻨﺼﻟا تﺂﺸﻨﻤﻠﻟ تﺎﻔﻠﺨﻤآ
ﻢآاﺮﺗ نﺈﻓ ﻪﻴﻠﻋو .ثﻮﻠﺘﻟا ﺮﻃﺎﺨﻤﻟ ﻲﻠﺤﻤﻟا ﻊﻤﺘﺠﻤﻟاو ﻊﻧﺎﺼﻤﻟا ﻞﺧاد ﻦﻴﻠﻣﺎﻌﻟا ضﺮﻌﻳ ﺎﻤﻣ
نأ ﻦﻜﻤﻳ (Cd، Pb ﻞﺜﻣ) ﺔﻣﺎﺴﻟا ﺎًﺻﻮﺼﺧ نﺎﺴﻧﻹا ﻢﺴﺟ ﻲﻓ ندﺎﻌﻤﻟا ﻩﺬه ﻦﻣ ﺔﻴﻟﺎﻋ تﺎﻳﻮﺘﺴﻣ
ﻰﻟإ سﺎﺳﻷا ﻲﻓ ﺔﺳارﺪﻟا ﺖﻓﺪه . ﺪﻴﻌﺒﻟا ىﺪﻤﻟا ﻰﻠﻋ ﺺﺧﻷﺎﺑو ةﺮﻄﺧ ﺔﻴﺤﺻ تاﺮﻴﺛﺄﺗ ﻰﻟإ يدﺆﻳ
حﻼﺻإ شرو اﺬآو يﺰآﺮﻤﻟا مﻮﻃﺮﺨﻟا ﻚﺒﺴﻣ ﻲﻓ ﻦﻴﻠﻣﺎﻌﻟا ﻲﺘﻋﻮﻤﺠﻣ ﺖﻧﺎآ اذإ ﺎﻤﻴﻓ ﺪﻳﺪﺤﺗ
ﺔﺿﺮﻋ ﺮﺜآأ (ﻢآ3≈مﻮﻃﺮﺨﻟا ﺔﻨﻳﺪﻣ ﺰآﺮﻣ بﻮﻨﺟ ﺔﻤﻳﺪﻘﻟا ﺔﻴﻋﺎﻨﺼﻟا ﺔﻘﻄﻨﻤﻟا ﻲﻓ) تﺎﺒآﺮﻤﻟا
ﺔﻴﻋﺎﻨﺼﻟا ﺔﻘﻄﻨﻤﻟا ﻦﻣ بﺮﻘﻟﺎﺑ ﻦﻴﻨآﺎﺴﻟاو ﺎًﻴﻨﻬﻣ ﻦﻴﺿﺮﻌﻤﻟا ﺮﻴﻏ ﻦﻴﻨﻃاﻮﻤﻟا ﻦﻣ ﺔﻠﻴﻘﺜﻟا ندﺎﻌﻤﻠﻟ
ﻦﻣ ﺪﻌﺑأ ﺔﻓﺎﺴﻣ ﻰﻠﻋ ﻦﻴﻨآﺎﺴﻟا ﻦﻣ ﺔﺿﺮﻋ ﺮﺜآأ ﻢهروﺪﺑ ءﻻﺆه نﺎآ ﺎﻣ اذإ و ،(ﺔﻠﻴﻣﺮﻟا ﻲﺣ)
.(ﻲﺑﺮﻌﻟا قﻮﺴﻟا ﻲﺣ ،مﻮﻃﺮﺨﻟا ﺔﻨﻳﺪﻣ ﺰآﺮﻣ ﻲﻓ) ﺔﻴﻋﺎﻨﺼﻟا ﺔﻘﻄﻨﻤﻟا
و ﺔﻔﻠﺘﺨﻤﻟا ﻞﻤﻌﻟا تﺎﺌﻴﺑ ﻲﻓ ندﺎﻌﻤﻠﻟ ﻲﻨﻬﻤﻟا ضﺮﻌﺘﻟا فوﺮﻇ ﻰﻠﻋ ﺮﺒآأ ﻞﻜﺸﺑ ﺔﺳارﺪﻟا تﺰآر
أ لﺎﻤﻌﻟا ﺔﻋﻮﻤﺠﻣ) يﺰآﺮﻤﻟا مﻮﻃﺮﺨﻟا ﻚﺒﺴﻣ ﻦﻣ ﻼً ﻣﺎﻋ 30 ﺖﻠﻤﺷو ،ﺔﺒﺣﺎﺼﻤﻟا ﺔﻴﺤﺼﻟا ﻞآﺎﺸﻤﻟا
(W.G-B، ب لﺎﻤﻌﻟا ﺔﻋﻮﻤﺠﻣ) تﺎﺒآﺮﻤﻟا حﻼﺻإ شرو لﺎﻤﻋ ﻦﻣ ﻞﻣﺎﻋ 34 و ،(W.G-A،
ﻰﻟإ ﺔﻓﺎﺿﻹﺎﺑ ،ﻢﻬﻠﻤﻋ تﺎﺌﻴﺑ ﻲﻓ ﺔﻠﻴﻘﺜﻟا ندﺎﻌﻤﻠﻟ اﻮﺿﺮﻌﺗ ﺪﻗ اﻮﻧﻮﻜﻳ نإ ﻞﻤﺘﺤﻤﻟا ﻦﻣ ﻦﻳﺬﻟا
،ﻲﺌﻴﺒﻟا ثﻮﻠﺘﻠﻟ ﻢﻬﺿﺮﻌﺗ ﺔﻴﻟﺎﻤﺘﺣﻻ ﺔﻠﻴﻘﺜﻟا نﺎﻌﻤﻠﻟ ﺎًﻴﻨﻬﻣ ﻦﻴﺿﺮﻌﻤﻟا ﺮﻴﻏ ﻦﻴﻨﻃاﻮﻤﻟا ﻦﻣ ﻦﻴﺘﻋﻮﻤﺠﻣ
ﺔﻘﻄﻨﻤﻟا نﺎﻜﺳ ﻦﻣ ﺺﺨﺷ12ﻦﻣ نﻮﻜﺘﺗ (S.G-C،ج ﻦﻴﻨﻃاﻮﻤﻟا ﺔﻋﻮﻤﺠﻣ) ﻰﻟوﻷا ﺔﻋﻮﻤﺠﻤﻟا
نﻮﻜﺘﺗ (S.G-D، د ﻦﻴﻨﻃاﻮﻤﻟا ﺔﻋﻮﻤﺠﻣ ) ﺔﻴﻧﺎﺜﻟا ﺔﻋﻮﻤﺠﻤﻟا ﺎﻤﻨﻴﺑ ،ﺔﻴﻋﺎﻨﺼﻟا ﺔﻘﻄﻨﻤﻟا ﻦﻣ ﺔﺒﻳﺮﻘﻟا
.ﺔﻴﻋﺎﻨﺼﻟا ﺔﻘﻄﻨﻤﻟا ﻦﻣ ﺎًﺒﻳﺮﻘﺗ ﻢآ 3 ﺪﻌﺑ ﻰﻠﻋ ﻦﻴﻨآﺎﺴﻟا ﻦﻣ ﺺﺨﺷ 20 ﻦﻣ
ﻊﻤﺠﻟ ﺔﻤﻤﺼﻤﻟا ﺔﻧﺎﺒﺘﺳﻹا ﺔﺌﺒﻌﺗ و ،تﻼﺑﺎﻘﻤﻟا ،تﺎﻈﺣﻼﻤﻟا ﻦﻳوﺪﺗ لﻼﺧ ﻦﻣ تﺎﻧﺎﻴﺒﻟا ﺖﻌﻤﺟُ
ﺔﻌﻴﺒﻃ ، (لﻮﺤﻜﻟا و كﺎﺒﻤﺘﻟا ماﺪﺨﺘﺳا ،ﻦﻴﺧﺪﺘﻟا) ﻲﻣﻮﻴﻟا ﻲﺗﺎﻴﺤﻟا ﻂﻤﻨﻟا، ﺔﻴﺼﺨﺸﻟا تﺎﻣﻮﻠﻌﻤﻟا
تﺮﻴﺘﺧاو ،ﺔﻴﺿﺮﻤﻟا يوﺎﻜﺸﻟا و ﺔﻣﻼﺴﻟا تاﺪﻌﻣ ماﺪﺨﺘﺳا ،ﺔﻠﻤﺘﺤﻤﻟا ﺔﻴﻨﻬﻤﻟا ﺮﻃﺎﺨﻤﻟا ،ﻞﻤﻌﻟا
.ﺔﻴﺸﻴﻌﻤﻟا ﺔﻟﺎﺤﻟا و ﺮﻤﻌﻟا ﺚﻴﺣ ﻦﻣ ﺔﻠﺛﺎﻤﺘﻣ نﻮﻜﺘﻟ ﻊﺑرﻷا ﺔﺳارﺪﻟا تﺎﻋﻮﻤﺠﻣ
لﺎﻤﻌﻟا ﺮﻓﺎﻇأ ﻲﻓ ( Mn، Cr، Pb) ندﺎﻌﻤﻟا تﺎﻳﻮﺘﺤﻣ نأ ﻰﻟإ مﺎﻋ ﻞﻜﺸﺑ ﺔﺳارﺪﻟا ﻩﺬه ترﺎﺷأ
ﺔﻴﺋﺎﺼﺣإ ﺔﻟﻻد دﻮﺟو ﻊﻣ (S.G) ﺎًﻴﻨﻬﻣ ﻦﻴﺿﺮﻌﻤﻟا ﺮﻴﻏ ﻦﻣ ﺮﺒآا ﺖﻧﺎآ (W.G) ﺎًﻴﻨﻬﻣ ﻦﻴﺿﺮﻌﻤﻟا
؛ﺔﻬﺑﺎﺸﺘﻣ ﺖﻧﺎآ S.G و W.G ﻦﻴﺘﻋﻮﻤﺠﻤﻟا ﻼآ ﻲﻓ FN-Cd تﺎﻳﻮﺘﺴﻣ نأ ﻆﺣﻮﻟ ؛ (p<0.05)
  V
ﺲﻜﻌﻟا ﻰﻠﻋو ،W.G-B ﻰﺘﺣ وأ S.G-D ﻦﻣ ﻰﻠﻋأ ﺖﻧﺎآ S.G-C ﻲﻓ FN-Cd نﺈﻓ ﻚﻟذ ﻊﻣو
و p<0.05) لﺎﻤﻌﻟا ﺮﻴﻐﺑ ﺔﻧرﺎﻘﻣ لﺎﻤﻌﻟا ﺮﻓﺎﻇأ ﻲﻓ ﻞﻗأ Fe و Cu ﺰﻴآﺮﺗ تﺪﺟو ﻚﻟذ ﻦﻣ
ﻰﻠﻋأ ﻦﻴﻨﻃاﻮﻤﻟا و لﺎﻤﻌﻟا ﺮﻓﺎﻇأ تﺎﻨﻴﻋ ﻲﻓ Cd و Pb ﺰﻴآﺮﺗ تﺎﻄﺳﻮﺘﻣ .(ﻲﻟاﻮﺘﻟا ﻰﻠﻋ p>0.05
(Cu و Fe، Cr، Mn) ﺔﻴﻘﺒﺘﻤﻟا ندﺎﻌﻤﻠﻟ ﺔﻴﻌﻴﺒﻄﻟا دوﺪﺤﻟا ﻲﻓ ﺖﻠﻇ ﺎﻤﻨﻴﺑ .ﺔﻴﻌﻴﺒﻄﻟا تﻻﺪﻌﻤﻟا ﻦﻣ
تﻻﺪﻌﻤﻟا ﻦﻋ لﺎﻤﻌﻟا ﺮﻓﺎﻇأ ﻲﻓ Cu ىﻮﺘﺴﻣ ضﺎﻔﺨﻧا ءﺎﻨﺜﺘﺳﺈﺑ ﺔﺳارﺪﻟا ﺖﺤﺗ تﺎﻋﻮﻤﺠﻤﻟا ﻞآ ﻲﻓ
ﻚﺒﺴﻣ ﻲﻓ ﺎًﺻﻮﺼﺧ لﺎﻤﻌﻟا طﺎﺳوأ ﻲﻓ ﺔﻴﺿﺮﻤﻟا ضاﺮﻋﻷاو يوﺎﻜﺸﻟا تﺮﺸﺘﻧا .ﺔﻴﻌﻴﺒﻄﻟا
ﻊﻗاﻮﻣ ﻦﻣ ةذﻮﺧﺄﻤﻟا ءاﻮﻬﻟا تﺎﻨﻴﻌﻟ ﺔﻴﺌﻴﺒﻟا تﺎﺳﺎﻴﻘﻟا تﺮﻬﻇأ. (W.G-A) يﺰآﺮﻤﻟا مﻮﻃﺮﺨﻟا
ﺎﻬﺑ حﻮﻤﺴﻤﻟا دوﺪﺤﻠﻟ ﺎًﻧﺎﻴﺣأ ﺎهزوﺎﺠﺗ ﻊﻣ (Pb & Cd ﻞﺜﻣ) ندﺎﻌﻤﻟا ﺾﻌﺑ ﺰﻴآﺮﺗ عﺎﻔﺗرا ﻞﻤﻌﻟا
.ﻊﻗاﻮﻤﻟا ﺾﻌﺑ ﻲﻓ
ﻰﻟإ ﺔﻄﺳﻮﺘﻤﻟا ﺔﺟرﺪﻟا ﻦﻣ ﺔﺋﺮﻟا ﻞآﺎﺸﻤﻟ ﺔﺒﺴﻧ ﻰﻠﻋأ نأ ﺔﺋﺮﻠﻟ ﺔﻴﺴﻔﻨﺘﻟا ﻒﺋﺎﻇﻮﻟا تﺎﺳﺎﻴﻗ تﺮﻬﻇأ
ﻢﻬﻴﻠﻳ (%20) ﻚﺒﺴﻤﻟا لﺎﻤﻋ طﺎﺳوأ ﻲﻓ ﺖﻠﺠﺳُ (يداﺪﺴﻧﻹا وأ يرﺎﺼﺤﻧﻹا عﻮﻨﻟا ﻦﻣ) ﺔﻤﻴﺴﺠﻟا
ﺖﻠﺠﺳُ ﻚﻟذ ﻊﻣو ؛ﻦﻴﻨﻃاﻮﻤﻟا ﻦﻴﺑ تﻻﺎﺤﻟا ﻩﺬه ﻞﺜﻣ ﻞﺠﺴﺗ ﻢﻟ ﺎﻤﻴﻓ ،(%10) تﺎﺒآﺮﻤﻟا شرو لﺎﻤﻋ
ﻲﻟاﻮﺣ ﻲﻟإ ﺔﻓﺎﺿﻹﺎﺑ ،مﺎﻋ ﻞﻜﺸﺑ ﻦﻴﻨﻃاﻮﻤﻟا ﻦﻴﺑ (ﺔﻳرﺎﺼﺤﻧﻹا ) ﺔﻔﻴﻔﺨﻟا ﺔﺟرﺪﻟا ﻦﻣ ةﺪﻳﺪﻋ تﻻﺎﺣ
ترﺎﺷأ .(S.G-D) ﺔﻨﻳﺪﻤﻟا ﺰآﺮﻣ ﻲﻓ ﻦﻴﻨﻃﺎﻘﻟا طﺎﺳوأ ﻲﻓ (ﺔﻳداﺪﺴﻧﻹا ) ﺔﻔﻴﻔﺨﻟا ﺔﺟرﺪﻟا ﻦﻣ %9
ﻲﻓ ﻞﻤﻌﻟا ﺪﻨﻋ ﺎًﻴﻤﻟﺎﻋ ﺎﻬﺑ ﻰﺻﻮﻤﻟا ﺔﻳزاﺮﺘﺣﻹا تاءاﺮﺟﻹا ﻒﻌﺿ وأ ﻖﻴﺒﻄﺗ مﺪﻋ ﻰﻟإ ﺔﺳارﺪﻟا
.ﺔﻠﻴﻘﺜﻟا ندﺎﻌﻤﻟﺎﺑ ﺔﺛﻮﻠﻤﻟا تﺎﺌﻴﺒﻟا
ﺺﺧﻷﺎﺑو ﺔﻠﻴﻘﺜﻟا ندﺎﻌﻤﻟا ﻦﻣ ﺔﻴﻟﺎﻋ تﺎﻳﻮﺘﺴﻤﻟ اﻮﺿﺮﻌﺗ ﺪﻗ لﺎﻤﻌﻟا نأ ﻲﻟإ ﺔﺳارﺪﻟا ﺖﺼﻠﺧ
ﻲﻓ ﻲﻨﻬﻤﻟا ضﺮﻌﺘﻠﻟ ﺔﺠﻴﺘﻨآ (ﻦﻴﻨﻃاﻮﻤﻟا ﺪﻨﻋ ﻞﻗأ ﺎﻬﺗﺎﻳﻮﺘﺴﻣ ﺖﻧﺎآ) (Pb & Cd) ﺔﻣﺎﺴﻟا ندﺎﻌﻤﻟا
بﻮﻠﻄﻤﻟا و ﺎًﻴﻤﻟﺎﻋ ﺎﻬﺑ ﻰﺻﻮﻤﻟا ضﺮﻌﺘﻟا ﺐﻨﺠﺘﻟ ﺔﻳزاﺮﺘﺣﻹا تاءاﺮﺟﻺﻟ رﺎﻘﺘﻓﻻا ﻊﻣ ﻞﻤﻌﻟا ﺔﺌﻴﺑ
لﻼﺧ ﻦﻣ ﺲﻜﻌﻧا ﺮﻴﺒآ ﺮﻄﺧ ﻲﻓ لﺎﻤﻌﻟا ﺔﻣﻼﺳ و ﺔﺤﺻ ﻞﻌﺟ اﺬهو ،فوﺮﻈﻟا ﻩﺬه ﻞﺜﻣ ﻲﻓ ﺎﻬﻘﻴﺒﻄﺗ
.ىﺮﺧﻷا ﺔﻴﻨﻬﻤﻟا ضاﺮﻣﻷا و ﻲﻧﺪﻌﻤﻟا ﻢﻤﺴﺘﻟا

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CONTENTS
TITLE  PAGE 

DEDICATION………………………………………………………………………….. I
ACNOWLEDGEMENTS………………………………………………………………. II
ABSTRACT……………………………………………………………………………… III
ARABIC ABSTRACT…………………………………………………………………… V
CONTENTS…………………………………………………………………………….. VII
ABBREVIATIONS………………………………………………………………………. X
LIST OF TABLES……………………………………………………………………….. XII
LIST OF FIGURES……………………………………………………………………… XIV

CHAPTER ONE
1
INTRODUCTION

CHAPTER TWO
10
LITERATURE REVIEW
2.1 Classification of Metals…………………………………………………………. 10
2.2 Heavy Metals……………………………………………………………………. 11
2.3 Uses of Heavy Metals…………………………………………………………… 12
2. 4 Pollution Sources with Heavy Metals…………………………………………. 13
2.4.1 Natural sources……………………………………………………………... 13
2.4.2 Anthropogenic sources…………………………………………………….. 14
2.5 Exposure to Heavy Metals………………………………………………………. 14
2.5.1 Environmental Exposure………………………………………………….. 16
2.5.2 Occupational Exposure …………………………………………………… 18
2.6 Physiological Routes of Exposure……………………………………………… 19
2.7 Toxicokinetics of Metals………………………………………………………... 22
2.7.1 Absorption and Distribution……………………………………………… 22
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2.7.2 Metabolism and Storage………………………………………………….. 23
2.7.3 Excretion…………..…………………………………………………….. 23
2.8 Exposure Effect to Metals………………………………………………………. 24
2.8.1 The mechanism of effect and toxicity……………………………………... 24
2.8.2 Specific Heavy Metals and their Risks…………………………………….. 30
2.9 Exposure Assessment to Heavy Metals………………………………………… 39
2.9.1 Environmental Monitoring……………………………………………….. 40
2.9.2 Biological Monitoring…………………………………………………….. 45
2.10 Analytical Techniques Used for Metals Analysis……………………………... 49
2.11 Media for Biological exposure Monitoring…………………………………… 50
2.11.1 Human Nails as Bio-indicators of Metal Exposure……………………… 51
2.11.2 Nails in Comparison to Other Commonly Used Biomonitors………… 54
2.11.3 Influencing Factors on Metal Concentrations in Nails ……………….. . 57
2.11.4 Relative Metal Levels in Nails and Other Samples……………………... 62
2.12 Lung Function Testing………………………………………………………… 63
2.13 Exposure Controls/Personal Protection……………………………………... 67
2.13.1 Elimination (elimination or abatement of the hazard)…………………. 69
2.13.2 Substitution and Process Modification ………………………………….. 69
2.13.3 Engineering Controls…………………………………………………….. 70
2.13.4 Administrative Controls…………………………………………………. 73
2.13.5 Personal Protective Equipment (PPE)………………………………….. 80

CHAPTER THREE
84
MATERIAL AND METHODS
3.1 Study Population (Subjects Examined)………………………………………… 84
3.2 Descriptions of Industries Chosen…………………………………………. …. 85
3.2.1 Khartoum Central Foundry……………………………………………….. 85
3.2.2 Automobile Body Repair Shops…………………………………………… 91
3.3 Primary and Observational Survey……………………………………………… 93
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3.4 Data Collection………………………………………………………………….. 94
3.5 Environmental Monitoring (Personal Exposure Monitoring)………………… 95
3.6 Biological Monitoring (Collection and Analysis of Nail Samples)…………… 96
3.7 Pulmonary Function Tests……………………………………………………… 98
3.8 Data Analysis…………………………………………………………………….. 100

CHAPTER FOUR
101
RESULTS
4.1 Population Characteristics……………………………………………………… 101
4.2 Awareness about the Hazards of Exposure to Heavy Metals…………………. 105
4.3 Health Conditions (Problems) ………………………………………………… 107
4.4 Job Conditions at Workplaces………………………………………………….. 109
4.5 Occupational Health and Safety Precautions in the Workplaces……………... 113
4.6 Metal Concentrations in Fingernail Samples ………………………………….. 120
4.7 Metal Concentrations in the Air of the Workplaces………………………….. 139
4.8 Lung Function Measurements………………………………………………….. 141

CHAPTER FIVE
DISCUSSION……………………………………………………………………….… 146
162
CONCLUSION………………………………………………………………..……
RECOMMENDATION…………………………………………………………… 163
REFERENCES……………………………………………………………………… 167
APPENDIX …………………………………………………………………….…… 189

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