Petroleum microbiology oil while A. borkumensis simutaneously increases synthesis of anionic glucoproteins, which are used to emulsify hydrocarbons in the environment and increase their bioavailability. The presence of crude oil along with appropriate levels of nitrogen and phosphor catalyzes the removal of petroleum either by mechanisms that enhance the efficiency of substrate uptake or by direct biodegradation of aliphatic chains. Two well-known oil spills exemplify large scale marine bioremediation applications: In 1989, the Exxon Valdez ran aground, spilling 41.6 million liters of crude oil, and launching one of the first major bioremediation efforts for an oil spill. Cleanup of Alaskan shorelines relied
Oil tanker instrument, Shell consulted the "London Tanker Brokers’ Panel (LTBP)". At first, they divided the groups as "General Purpose" for tankers under ; "Medium Range" for ships between 25,000 and and "Large Range" for the then-enormous ships that were larger than . The ships became larger during the 1970s, which prompted rescaling. The system was developed for tax reasons as the tax authorities wanted evidence that the internal billing records were correct. Before the New York Mercantile Exchange started trading crude oil futures in 1983, it was difficult to determine the exact price of oil, which could change with every contract.