Date: 202001
Location: ZZZ.Airport, US
Aircraft: B737-800
Operator: Air Carrier
Operating under: Part 121
Flight plan: IFR
Mission: Passenger
Flight phase: Taxi
Reporter organization: Air Carrier
Reporter function: Flight Attendant (On Duty)
Reporter qualification: Flight Attendant Current
Human factors: Physiological - Other; Workload
Anomaly: Aircraft Equipment Problem Less Severe; Deviation / Discrepancy - Procedural Published Material / Policy; Flight Deck / Cabin / Aircraft Event Illness / Injury; Flight Deck / Cabin / Aircraft Event Smoke / Fire / Fumes / Odor
Detector: Person Flight Attendant; Person Flight Crew
When detected: Taxi
Result: Flight Crew Returned To Gate; General Flight Cancelled / Delayed; General Maintenance Action
Contributing factors: Environment - Non Weather Related; Human Factors
Primary problem: Environment - Non Weather Related

Narrative: I was working as the #4 [Flight Attendant]; leaving ZZZ. During the taxi; the #2 and I smelled an odor that resembled tar and eggs. Minutes later the Captain called and asked if we smelled anything. We said yes and described the odor. The #1 and #3 up in the front also smelled it. The Captain circled around to see if it would dissipate; but it did not. We went back to the gate. All of the flight attendants had headaches. I also felt a slight pain in my chest and short shallow breathing. After discussion with the Captain and crew; we deplaned the passengers and went with the paramedics to test our vital signs. I gave the #1 one of the fume event yellow plastic cards to keep for reference and explained that fume events are serious. She has only been flying 2 years. After we were checked; the paramedics said we were ok. While waiting; I turned my phone on to text my Supervisor and to call Operations. My Supervisor said the #1 needed to call Operations. I let her use my phone to call Operations. We waited for the mechanics to determine what caused the odor. We were told that bovine serum had spilled and mixed with dry ice in cargo and that was the issue. By time they remedied the situation; the crew felt well enough to fly back to ZZZ1.While taxiing out; we stopped and sat. The Captain said that weights and balances needed to be done by hand and that it is normally done by computer and that it would take some time. We sat on the tarmac for about 20 minutes. During that time the #2 and I smelled exhaust fumes. We sat there breathing the fumes. While this does frequently happen when sitting in the back; it doesn't reduce the health risks; symptoms or discomfort. My nose was burning and I was; again; getting a headache. The #2 and I did not call the Captain as we wanted to get home after the morning we had; and the total trip. We took off finally. When we were up in the air; I called the Captain and told him about the exhaust fumes. He said we would discuss [it] once on the ground. When we got to ZZZ1; the Captain wanted to have a debrief. He told me that I was wrong not to call him about the exhaust fumes. I said he was right and I apologized. The #3 then said; that happens all the time and is normal. I cut him off saying; it might be common but it is not something we should be breathing and has health effects. The #1 rolled her eyes and said I complained about everything. She abruptly stood up and said she was leaving and didn't need this. The Captain handled this professionally and responsibly. I was confident that he was taking care of the crew.The managers and Captain finished the meeting and everyone left. I was the only one who went to be tested. The others knew they had this option but elected to go home. I was looked at by a nurse practitioner. She looked in my nose and throat; took my vitals and offered me saline nose spray and a Tylenol. I showed her the yellow card and said I needed to have blood taken for carbon monoxide. She said she had to ask the doctor. Another person came in and he said I had to get a claim report. I said I didn't know anything about how to do this. He gave me the paper to call [Administration]; which I did. They said it would be 24-48 hours for a claim # and he said that was ok.




Synopsis: B737-800 Flight Attendant reported physiological symptoms resulting in a ground return to the gate. Fumes were caused by non-hazardous cargo spill.