The Effects of PBDE‐99 on Lysosomal Membrane Stability in Coelomocytes of the Earthworm Lumbricus terrestris Using the Neutral Red Retention Test

Abstract

Flame retardants, such as polybrominated diphenyl ethers (PBDEs) have recently been found to have toxic side effects due to their bioaccumulative nature. Their widespread use on materials such as electronics, furniture, and plastics has led to contamination of natural environments and exposure to various living organisms, including humans. Lysosomal membrane stability is used as a biomarker of pollutant stressors and is measured using the Neurtral Red Retention test. Neutral Red Retention time measures the length of time it takes red dye to escape from the lysosome into the cytosol, indicating cellular damage. Lumbricus terrestris earthworms were exposed to a medium concentration of PBDE‐99 (50 ng/g dry soil) and a high concentration (250 ng/g dry soil) for one week. After exposure, coelomocytes (gut cells) were extracted using sonication, techniques. Data indicated that treatment with PBDEs resulted in a significant increase in the percentage of cells exhibiting red cytosol per minute. The percent increase in red cells/min. increased from 0.21 to 0.53 from the control to the high group. Decreased lysosomal membrane stability in the high concentration group suggested that PBDEs impaired cellular activity in the earthworm model, potentially making the cells susceptible to degradation by their own hydrolytic enzymes.