Organochlorine Pesticides, Polychlorinated Biphenyls and Heavy Metals Residues in Myctophids off South West Coast of India

Abstract

Though myctophids are widely distributed in the
Indian oceanic waters and contribute to a large
proportion of the deep-sea fish biomass, the
information regarding the presence of lipophilic
chemical contaminants and heavy metals in these
lipid-rich lantern fishes are relatively scanty.
Analyses on the occurrence of heavy metals,
organochlorine (OCPs) and polychlorobiphenyls
(PCBs) in myctophids from Indian waters showed
presence of organochlorine pesticides in Diaphus
watasei, Diaphus luetkeni and Myctophum obtusirostre.
The prominent pesticides detected in the fish tissue
include endrin, dieldrin, heptachlor epoxide, α-BHC
and heptachlor. Dieldrin and heptachlor epoxide
were detected in M. obtusirostre while DDT isomers
in D. luetkeni. The total PCB levels followed the
order D. luetkeni> D. watasei>M. obtusirostre and 2,
2’, 3’, 4, 5 – pentachlorobiphenyl and 2, 3, 3’, 4’, 6-
pentachlorobiphenyl. Trace metals (Fe, Zn, Cu and
Mn) Composition is comparable with other fish
species reported and followed the order D. luetkeni>
M. obtusirostre> D. watasei. Results showed that
POPs and heavy metal levels in myctophid species
studied were much below the regulatory limits.