Reducing pesticide levels in tea – The role of chemical ecology
Thursday, 7 May 2015 at 1:23:PM
Did you know that India is no longer the world’s biggest
producer of tea? It was actually overtaken about 10 years ago by China, who now
contribute about 36% to global tea production. So it will come as no surprise
that China takes its tea industry very seriously – as
I found out first-hand when I recently visited the Tea Research Institute, near
Hangzhou in Zhejiang Province.
The institute (see picture) has a long history, having been
founded in 1958. It’s quite a size too – there’s one big building over four
floors, and a number of smaller annexes, all surrounded by undulating fields of
The reason for my visit was to meet one of our TD-100 customers,
Professor Chen Zong-mao, ask him how his studies are going, and to discuss our
latest technologies for TD and TOF MS. Professor Chen has been a tea researcher
since the 1960s, and as Chairman of the International Tea Symposium is highly respected in this area.
Professor Chen told me that his team has recently been
looking at ways to reduce pesticide use in tea plantations, by studying how the
volatiles produced by plants mediate interactions with insects – an area known as
‘chemical ecology’. However, existing analytical protocols – including taking
‘bag’ samples directly into the column – simply weren’t up to the job. In
particular, he needed a much more sensitive way of detecting the very low
levels of VOCs present in the environment of tea plantations.
To solve this problem, a couple of years ago he bought one
of our TD-100 thermal desorbers to increase the sensitivity of his analyses. Professor
Chen told me that, since he began using the TD-100, he’s been able to detect chemicals
at levels as low as 1–2 ng/L, which has been a great help to him when studying
the chemical ecology of tea plants.
This is important because there is concern over pesticide residues in tea – and although the effects on human health are hotly debated, reducing pesticide use through approaches such as integrated pest management is of course beneficial for the environment more widely. Understanding
the role that tea volatiles play in plant–insect–predator interactions therefore
provides the sound scientific basis you need when developing more
environmentally friendly approaches to tea cultivation.
That’s enough writing for the moment. I’m off for a cup of tea!
Hannah Calder is Thermal Desorption Product Specialist at
Markes International, where she has been for 1½ years. Hannah studied Chemistry at
Cardiff University, and now uses her TD experience to help customers and
staff with technical enquiries, assisting with application work in Markes’
laboratory – and of course doing the tea rounds!