| dc.description.abstract | Research was aimed to determine toxic concentration of oil drilling waste (cuttings), causing death of 50% (LC 50) population of shrimp post larvae of Penaeus monodon through bioassay. LC 50 describes toxicity of drilling waste that is utilized for consideration of the next waste handling, whether it is allowed or not to be directly discharged to the environment without prior treatment to decrease its toxicity. Drilling waste handling refers to Ministry of Energy and Mineral Decree No. 045/2006. Drilling waste (cuttings) was collected from Babelan, North Bekasi. P. monodon post larvae were taken from Hatchery in Tanjung Pasir, Tangerang. Software of EPA Probit Program Version 1.5. was applied for counting LC50. After 72 to 96 hours observation, most of the shrimp larve on all test media except controls began to die. Symptoms of shrimp larvae before death die was very weak movement and very weak in response to stimuli from the outside. Death was characterized by the presence of mucus and changes in body color. Based on the results obtained by probit analysis, LC 50 value of drilling waste against shrimp (P. monodon) in the exposure time of 24, 48, 72 and 96 hours were 154,333 ppm 139,862 ppm 107,169 ppm and 91,706 ppm, respectively. Drilling waste was not toxic because the value of LC 50 - 96 hours is still within the limits set by the government (≥ 30,000 ppm). Thus, drilling waste was allowed to be discharged to the environment without the necessity of prior treatment. | en |
