MARTINEZ >> A massive fire that broke out at a refinery last month released more than 7,000 gallons of hydrocarbon materials into the air and required medical treatment for six workers, according to the 30-day report the company sent to Contra Costa Health Services officials.

The Martinez Refining Co. posted the report on social media Tuesday. The company said it submitted it to county officials Feb. 28.

The report said the six refinery workers were evaluated by medical personnel and released. None of them went to a hospital.

In the report, the refinery said it estimated that 170 barrels — 7,140 gallons — of hydrocarbons were released in the Feb. 1 blaze. An explosion and fire were reported at the refinery about 1:30 p.m. as two workers prepared to do planned maintenance on a process unit.

The blaze caused Bay Area gas prices to rise in the immediate aftermath.

The company reported that the hydrocarbons released were light cat cracked naphtha, light cat cracked distillates; intermediate cat cracked distillates; light thermal cracked naphtha; and isobutane-rich C3-C4.

According to the National Cancer Institute, exposure to hydrocarbons can increase the risk of certain types of cancers.

Air quality experts and environmental officials referred questions about the severity of the blaze and the chemicals it released to Contra Costa Health Services. That department did not comment other than to offer an infographic in which the department said that the agency’s measurements “show that concentration of these chemicals in the air during the event were mostly below the threshold to be considered dangerous.”

Health officials also said the strong winds that day “protected most people near the fire from prolonged exposure to smoke.”

The company wrote that its best estimate indicated 30 combined barrels (1,260 gallons) of the light thermal cracked naphtha and the isobutane-rich C3-C4; 20 combined barrels (840 gallons) of the light cat cracked naphtha and light cat cracked distillates; and 120 barrels (5,040 gallons) of the intermediate cat cracked distillates were released.

The company also said it believes that Diethanolamine likely was released because of a ruptured pipe caused by the fire. That chemical is used in cosmetics, detergents and pharmaceuticals, according to the U.S. Food and Drug Administration.

Flaring that was needed for safety workers to respond to the unplanned shutdown of the refinery also caused more than 500 pounds of sulfur dioxide to be released, the company said.

The refinery said its operating units are still shut down, and that it is still assessing damage from the fire.

It did not have an estimate for when the operating units would open again.

The report follows the initial 72-hour report that the company issued immediately after the fire. The company is owned by PBF Energy Inc.