Date of Award


Document Type


Degree Name

Master of Science (MS)


Environmental Science

First Advisor

Dr. Abdulbari Bener

Second Advisor

Prof. J. Nelson Norman

Third Advisor

Dr. Ahmad Ayoob Alqadal


Arabian Gulf countries, witnessed rapid development in many aspects of life. Although these

developments have improved the quality of life in the UAE, they have drawbacks that generated

health problems and environmental hazards. One of the consequences of rapid development is the

usage of large amounts of pesticides in agricultural production for the sake of increasing the yield of crops. However, the expanded use of these pesticides is known to result in acute respiratory symptoms and changes in body metabolism. To-date, no population-based study has been conducted to investigate the effects of pesticides on plasma amino acids and liver enzyme levels in farm workers in the UAE in order to compare that with the published international studies.

The aim of this study is to determine the effect of pesticides on farm workers, to assess

pesticide exposure, and to identify possible risk factors associated with pesticide conditions

which cause adverse health effects. Additionally, the effects of pesticides on plasma amino acid

levels as well as the level s of liver enzymes have investigated among farmers and

non-farmers in the UAE. The results were compared with other available published studies.

This study was based on a matched case-control study of the pesticide exposed and non- exposed

Subject selected from the Al-Ain and the Emirates of Dubai, Sharjah, Fujairah, which be reprehensive of the UAEU Population the study subject consisted 103 cases of 105-controls matched for age, sex and nationality. The study conducted during May through June of 1997.

The study was conducted into two parts, namely:

a: An epidemiological study: Case-Control study;

b: Laboratory analysis Plasma amino acids and serum liver enzymes for cases and control s.

The socio-demographic characteristics of farmers and non-farmers were similar among

the population surveyed. Most of the farmers were not certain about pesticide

exposures. Both groups, farmers and non-farmers were demographically similar with

regards to age groups, nationality and marital status. The majority of farmers (6 1 . 2%) were

Illiterate, which was the expected result. The majority of non-farmers were educated

with secondary or high school educational certificates. Most farm workers were not aware of

the type of pesticides they might have been exposed.

The exposure to pesticide usage among farmers and non-farmers was investigated.

The majority of farmers reported using boots as the main method of protection, but the

majority of them were not using masks and gloves during spraying. The majority of farmers

reported different clinical symptoms. It was observed that diarrhea and cough were most

common symptoms prevalent among farmers. Also, other symptoms, such as, nausea/vomiting, red/irritated eye /blurred vision, increased anxiety, dizziness, discomfort, chest wheezing and asthma.

We have investigated Plasma amino acid profiles famers and non-farmers. Most plasma amino acid shows higher values among famers and non famers .There were statistically very highly significant differences between two groups with respect to concentration of some amino acids in plasma as can be seen as follows: essential amino acids such as, Histidine, Threonine, Lysine and Tryptophan, and non­ essential amino acids, such as, Taurine, Serine, Glutamic acid, Arginine, Glycine, and Ornithine.

Liver function tests were performed on famers and non-famers. Similar values of Total

Protein, Albumin, Total Bilirubin in, Aspartate transferase, Alanine Transferase and Alkaline

Phosphatase were obtained from farmers and non-farmers. There were no any statistically

significant differences between fanners cases and non-fanners except for Lactate Dehydrogenase

in farmers (3 73 .20 ± 86.74 uIl, Mean ± S. D); versus in non-­ farmers (3 40. 72 ± 87.49 uIl,

Mean ± S. D), (p = 0. 01 0).

Many farm workers reported occupational exposure to pesticides. One type of exposure derives from the application of pesticides as 60% of farm workers reported being involved with spraying crops directly with pesticides or working immediately adjacent to rig, 70% of the subjects reported working in fields with an obvious chemical smell, and 60% of them reported mixing pesticides.

The realities of agricultural working context, the lack of legal protections and severe

Weaknesses in the existing laws, combined with the toxic pesticides that are ubiquitous in the

Farming environment, make agricultural work especially hazardous.

The public health task is clear. Not only must more resources and priorities be given to biological monitoring and epidemiological studies of farmers, but also support should be given to

the effort s of farmers and farm workers to make their workplace safer. Overall, we hope that

our data will be useful for the establishment of an occupational exposure limit to the pesticide in the future.