Environmental Engineering Reference
In-Depth Information
letter, should be sealed with a tamper proof metal seal (to ensure the sample is not tampered with).
Bottles should be numbered, and the letter must follow a prescribed format, and provide the name and
a description of the samples written against each number. The recommendation is to send 600 to 800
grams of sample for chemical analyses (Kholkute 2003). One concern is that any carbofuran present
could go unnoticed if it were to undergo rapid breakdown due to metabolism (refer to Figure 1.9
in Chapter 1). Consequently, cooperation between individuals conducting the necropsy, and the
laboratory in which the samples are to be analysed, is essential to ensure the samples are processed
in good time.
4.8 Forensic facilities and analyses in India
Most samples collected in India are sent to forensic laboratories for analysis and determination of
poisoning. To ascertain the presence of carbofuran, the sample is extracted with chloroform or hex-
ane and subsequently analysed by thin layer chromatography (TLC, described in Chapter 1) using
a hexane-acetone or benzene-chloroform-ethyl acetate system. Titration is achieved using bromo-
cresol green as an indicator for quantifi cation. Carbofuran identifi cation in bait, stomach contents,
liver and kidney are considered confi rmative of poisoning. GC/MS is used to confi rm the presence
of a poison, once a sample tests positive by TLC.
Tewari and Ravikumar (2000) have described the history and development of forensic laborato-
ries in India. By 1990, most Indian States had their own State Forensic Laboratories (SFL) and there
were also Regional Forensic Laboratories (RFL) in major cities. Three Central Forensic Laboratories
(CFL) take care of research and development, and analyse cases from States/Union Territories that
do not have a forensic laboratory. The Central Forensic Laboratories have better facilities, and can
act in place of State Forensic Laboratories to solve complex investigations (Tewari and Ravikumar
2000). However, many Regional Forensic Laboratories themselves are located some distance from
certain Protected Areas where investigations regarding wildlife poisonings are carried out/required.
This creates diffi culty when submitting samples to the relevant laboratory, and only cases with clear
circumstantial evidence tend to be sent for poison confi rmation. The diffi culties posed by geographi-
cal distance, and a lack of transport infrastructure can unfortunately make toxicological analysis
'optional'. Consequently, cases of poisoning that do not offer suffi cient evidence on the ground
certainly go undiagnosed. The Wildlife Institute of India Forensic Laboratory (www.wii.gov.in),
and other laboratories in various educational institutions related to veterinary science (at the Indian
Veterinary Research Institute (IVRI; www.ivri.nic.in) in Bareilly, for example) also help investigate
wildlife crime.
Regional Forensic Laboratories have a predetermined list of OPC and carbamate compounds to
screen for, in addition to carbofuran:
1. Acephate
2. Anilofos
3. Chlorfenvinphos
4. Chlorpyrifos
5. Diazinon
6. Dichlorvos (DDVP)
7. Dimethoate
8. Edifenphos
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