Environmental Engineering Reference
In-Depth Information
Of course, the diversity and timeline observed will vary from site to site, across seasons and
according to the species of the deceased animal as well as the density and behaviour of other scaven-
gers. This timeline can be fi ne tuned as our stakeholders and researchers on the ground collect data on
insects over time and in these distinct conditions. In addition, we are unsure of how this timeline may
be impacted if the carcass being fed on is contaminated with a pesticide such as carbofuran. Given that
the insects which feed at contaminated carcasses can themselves become exposed and secondarily
poison the organisms that feed upon them, the author has also developed an outline for sampling/
observing insects at carcasses for toxicological analyses (Martins 2010, available upon request).
3.8 Analytical, legal and regulatory mechanisms in Kenya
Joseph O. Lalah
1
and Peter O. Otieno
2
1
Department of Chemical Sciences and Technology, School of Applied Sciences
and Technology, Kenya Polytechnic University College, P.O. Box 52428-00200
City Square, Nairobi, Kenya
2
Institute of Ecological Chemistry, Helmholtz Zentrum München, Ingolstädter
Landstraße 1, D-85764 Neuherberg, Germany
3.8.1 Analytical methodology required and research capacity
available in Kenya
The range and types of analyses, analytical instruments and techniques that are used to detect car-
bofuran and its metabolites as well as their relative costs and the analytical background required to
conduct analyses and interpret results are described in Chapter 1. Unfortunately, the existing ana-
lytical capacity in Kenya is currently no match for the frequent pesticide-related incidents of mass
mortality reviewed in this chapter. The presence/absence of carbofuran within a sample recovered
from the fi eld tends to be established using TLC. Other bioassay techniques (e.g., the ELISA method
and cholinesterase assays, described briefl y in Chapters 1 and 2, respectively) have not really been
explored in Kenya. And, while bioassay techniques are more rapid and require less training/analyti-
cal background to conduct and interpret, they are also considerably less specifi c.
When circumstances permit, samples are analysed using 'high precision' instruments such as
HPLC and GC/MS. HPLC systems are available in a few universities (e.g., Maseno University),
where they have been used to quantitatively analyse carbofuran in various matrices including water,
plants, soil and animal tissue after careful solvent extraction procedures which usually consist of
liquid-liquid, Soxhlet extraction or solid phase extraction (SPE), followed by column clean-up with
Florisil or silica gel and concentration before injection into the instrument (e.g., Otieno et al. 2009).
Within the entire country, we know of only a limited number of GC/MS instruments (i.e., up to
ten) in a few universities. For example, there are two GC/MS at the Jomo Kenyatta University of
Agriculture and Technology (JKUAT), both refurbished instruments donated by a UK-based charity.
We are also aware of two at research institutions, one at KEPHIS and one at the International Centre
of Insect Physiology and Ecology (ICIPE). To provide some perspective, Kenya covers an area
that is about twice the size of the US State of Nevada (i.e., a little under 583 000 km
2
). By contrast,
we also know of individual institutions in developed nations (e.g., North America and the United
Kingdom) which house approximately the same number of GC/MS instruments as there are in the
whole of Kenya. The cost of sending samples outside of Kenya for analysis, even within Africa, is
generally considered to be logistically and fi nancially prohibitive.
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