There are multiple definitions:

1. permissible exposure limit(English)

   • BeS, CBD, DOE, DWA, LTW, NIOSH, OEL, OSHA, TWA
   • Environment, Pollution and health, Toxicology, Safety and health
   • https://doi.org…459620701354747

2. primary effusion lymphoma(English)

   • a rare HIV-associated non-Hodgkin's lymphoma (NHL) that accounts for approximately 4% of all HIV-associated NHL. PEL has a unique clinical presentation in having a predilection for arising in body cavities such as the pleural space, pericardium, and peritoneum
   • HIV, NHL
   • Oncology
   • https://doi.org…logist.12-5-569