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Dr Beverley Wood, a Barbadian researcher, has undertaken studies to answer a question troubling fellow Bajans for decades - is their drinking water contaminated by agricultural pesticides?
Historically, the drinking water in this Eastern

Caribbean island comes from rainfall, which filters through the soil and is stored in the limestone aquifer from which it is pumped.
The tiny former British colony has boasted that this water is "pure" and "clean" because of a zoning system developed in the mid-20th century just before it became an independent nation.
Hydro-geological studies, in the 1960s created restriction zones around public water wells to prevent contaminants, mainly bacteria from sewage wells, getting into the water supply.
The areas were mainly under agriculture but the increasing use of agricultural chemicals has raised concerns of possible contamination by pesticides. The argument was if bacteria could filter through the soil in these areas to the aquifers, can’t pesticides too?
Dr Beverley Wood has shed some light on the impact of pesticide use on groundwater quality in her research "An assessment of Barbados’ groundwater for contamination by atrazine and its major dealkylated metabolites" - the first of its kind in Barbados - for her doctorate at the University of the West Indies (UWI) Cave Hill campus.
Dr Wood's survey identified the most commonly used pesticides in Barbados and the crops on which they were used. She decided on a study of the herbicide atrazine since it was used over large areas of sugar cane crop for a long period of time.
The study focused on groundwater in three catchments - St Michael, St Philip and the West Coast and the soils overlying these catchments in order to determine whether there were processes that could restrict and/or reduce the amount of pesticide that can reach groundwater.
The fieldwork involved taking samples of soil at different depths and over different periods of time after the pesticide was sprayed.
"I wanted to find out how the concentration of the applied pesticide varied over a period of time and under general environmental conditions that exist in Barbados," said Dr Wood.
"For example, in our warm dry climate one would expect rapid breakdown of the chemical and smaller quantities in the environment than what would be found in a temperate climate," she further added.
In another aspect of the research, the laboratory study examined how the characteristics of two Barbadian soil types in which sugar cane is cultivated could restrict the movement of pesticide to the groundwater.
"I found that the chemical readily breaks down under the Barbados environmental conditions," the former St Michael School and Barbados Community College student, explained.
"At the same time a characteristic of the soil is that it can bind the chemical to it but at the same time it can also release it, for example, after a heavy rainfall," she added.
Dr Wood’s analyses of groundwater samples from the three catchments showed just trace amounts of atrazine and its metabolites (break down chemicals) deethylatrazine and deisopropylatrazine, which supported the findings in the soil studies.
Due to the increasing use of agricultural chemicals in Barbados, her study has become a landmark work.
"When new pesticides are considered for importation into the island, atrazine can be used as a benchmark when assessing the potential impact of the use of these chemicals on groundwater quality," she explained.
Science, in general, is her passion and she can sit and talk all day about it without taking a breath. One of her areas of expertise is pesticides and water analyses, which she started as a laboratory technician at the Government Analytical Services in the early 1990s.
That laboratory also undertakes other chemical and microbiological analyses in water and in food.
Today, Dr Wood is director of the laboratory.
Beverley read for her Bachelor of Science degree in biochemistry and chemistry at the UWI St Augustine campus in Trinidad and Tobago. She later studied for her Master of Science in toxicology at the University of Surrey in England.
During her PhD research she also completed some courses in the advanced Diploma in Resource Management and Environmental Studies at CERMES, UWI Cave Hill campus.
The research also took her to the St Augustine campus as well as the National Hydrology Research Institute in Saskatoon, Saskatchewan, Canada.
She was conferred with her doctorate in October 2007.
"I understood from the outset that PhD research would be intensive and I was prepared for it but there were stumbling blocks along the way."
"There are not a lot of people studying similar subjects in the Caribbean that I could call on to discuss matters, neither was there much literature in the region on the subject."
"At the end of the day after I completed all the tests and the laboratory work, the most difficult part was writing the thesis."
"I know some people who finished their experiments, had all the data but threw in the towel because the writing was just too overwhelming."
"There were many times that I felt like giving up. Some days I was at home – feeling locked in like a prison - trying to write and could not get anything written but I could not have given up because so many persons along the way helped me that I felt that if I had given up, I would have disappointed them."
"There were many lessons I have learnt from this research experience that, if I had to do it again, I would do differently and if I had to supervise PhD students I would teach them about."
"It was good to provide some of the answers to the concerns with respect to the use of agricultural pesticides and groundwater contamination and to be able to provide planners and policy makers with some baseline information." She however noted that her study is just the beginning, and encouraged persons to use her work as a starting point for further study.
Among those whom she credits are God, her friends and family, colleagues, farmers and chemical distributors.
Beverley said she had to make a lot of sacrifices, but she believed it was all worth it.