We investigated eight organochlorine pesticides (OCPs) in the rivers
of southern part of Okinawa Island, Japan, from July to September 2005. The
mean concentration for ΣBHC (α, β, γ, δ-BHC) in
four rivers was 25.67 ± 58 ngL
$^{-1}$
(mean ±
SD). The highest concentration of BHC detected in water samples was 49.10
ngL
$^{-1}$
. Other OCPs such as Aldrin, Dieldrin, Heptachlor
epoxide (Isomer B) and Methoxychlor were also detected in most water samples
with their mean concentrations of 6.96 ± 80, 4.33 ± 59.9, 3.16
± 55 and 2.01 ± 57.6 ngL
$^{-1}$
. Within the
monitoring period, the concentration of OCPs increases in July and August
(Aldrin, α-BHC and β-BHC). The possible sources of these OCPs might
be the effluents and dusts from residential areas and agricultural activities.
The levels of OCPs in rivers in southern part of Okinawa were generally below
the guideline values in Japan. This preliminary documentation of OCPs in river
waters from southern part of Okinawa Island revealed that the rivers are
lightly contaminated and suggesting more monitoring studies in order to protect
the health of aquatic systems and accompanied life.
