PENGARUH KONTAMINASI INSEKTISIDA PROFENOFOS TERHADAP FISIOLOGIS IKAN NILA MERAH (Oreochromis sp.) (Contamination Effect of Profenofos Insecticide on Physiology of Red Nila (Oreochromis sp.))

ABSTRAK Peningkatan jumlah penduduk memicu aktivitas manusia yang cenderung merusak lingkungan. Penggunaan insektisida organofosfat berlebih berdampak pada pencemaran lingkungan perairan dan organisme di dalamnya. Penelitian ini bertujuan untuk mengetahui pengaruh kontaminasi profenofos (insektisida organofosfat) terhadap fisiologis ikan nila merah. LC50-96.Profenofos ditentukan dengan bantuan perangkat lunak Analisis Probit. Aktivitas kolinesterase plasma darah dan jaringan otak diperiksa menggunakan kolinesterase kit (DiaSys) secara spektrofotometri. Laju konsumsi oksigen (LKO2) diukur menggunakan respirometer. Kadar hemoglobin diperiksa dengan metode oksihemoglobin, hematokrit diukur dengan metode mikro-hematokrit. Desain penelitian menggunakan rancangan acak lengkap, dianalisis secara statistik dengan Anova. Selanjutnya jika terdapat beda nyata dilanjutkan dengan uji LSD (Least Significant Difference) serta persamaan regresinya. Gejala kematian ikan serta kualitas fisik dan kimia air uji diperiksa setiap hari, kemudian dianalisis secara deskriptif. Toksisitas curacron pada LC50-96 nila merah sebesar 2,105 ppm. Semakin besar dosis menurunkan aktivitas kolinesterase secara nyata (P>0,05) pada plasma darah dan jaringan otak. LKO2 setelah 1 jam pendedahan mengalami peningkatan, namun setelah 24 jam hingga 96 jam mengalami penurunan (P>0,01; R2=0,98). Semakin besar dosis selama 96 jam secara nyata meningkatkan kadar Hb (P>0,05; R2=0,95) namun tidak beda nyata pada hematokrit (R2=0,66). Penggunaan insektisida ramah lingkungan dan monitoring secara terus menerus dapat mengurangi dampak insektisida pada lingkungan perairan dan organisme di dalamnya.   ABSTRACT The increasing of human population triggers on human activities which are tend to impact on environment. Excessive use of organophosphate insecticides impact on pollution of the aquatic environment and also the organisme therein. The objective of this research was to study the effects of profenofos (an organophosphate insecticide) to the physiology of red nila. Preliminary research was conducted to find out the Lethal Concentration (LC50-96) of profenofos which was determined by software “Probit analysis”. Cholinesterase activity of blood plasma and brain tissue was examined spectrofotometically using cholinesterase kit (DiaSys). Rate of oxygen consumption was measured by Johnson’s modified respirometer methode. Hemoglobin were measured by oxyhemoglobin and hematocrit by micro-hematocrit methods, respectively. This research used complete random design. Data were analyzed statistically using analysis of variance (ANOVA), continued with Least Significant Difference (LSD) and regression test. Lethal Concentration (LC50-96) of profenofos to red nila was 2.10 mg/L. The results indicated that increasing dosage reduced cholinesterase activity (P<0.05) in blood plasma and brain tissue. Oxygen consumption rate increased after 1-hour exposure, but decreased after 24 to 96 hours (P<0.01; R2=0.98). Increasing dosage of profenofos exposure for 96 hours followed with increasing of Hemoglobin level significantly (P<0.05; R2=0.95), but it was not significantly different in hematocrit (P>0.05; R2=0.66). The use of environmentally friendly insecticides and continually monitoring can reduce the impact of insecticides on the environment and organism therein.