'Aviation union GMB demanded today that London City airport bring in independent monitors to assess the impact of excess fumes on passengers and staff.
The privately owned airport operates a unique parking system for aircraft, with the tail exhaust pointing directly into the passenger lounge.
According to the union, regular discharges of toxic fumes are propelled into the customer lounges with potentially long-term health implications.
Some employees have already been taken ill as a direct result of working in areas exposed to the poisonous fumes.
GMB organiser Stephanie Attwood said that members had reported signs of poisonous exposure including dry mouths, headaches and breathing difficulties.
"GMB members working in this area have to vacate the room on a daily basis in order to escape having to breathe in the toxic air," she said.
Ms Attwood also drew attention to the health of passengers and future visitors to the 2012 Olympics site, which is located in the area.
"Members of the travelling public who land at London City airport have to use this area too, as will competitors and visitors to the Olympics."
Employers at the airport are using "in-house" monitoring equipment to gauge the severity of the fumes and their potential effect on passengers.
Surprisingly, however, GMB has been denied access to the results of the tests and has expressed "serious doubts" about their accuracy and validity.
"We have received an independent environmental report which states that there were volatile organic compounds present in the air sampled, sufficient to cause discomfort and possibly ill health.
"GMB is amazed at London City airport's refusal to agree to full independent monitoring to this potentially dangerous situation," said Ms Attwood.
She appealed to employers at the airport to "get real" and "finally put the health of passengers first.
"The reality of the situation is that London City airport has chosen to sacrifice the health of their passengers and staff in order to line their pockets with high levels of profit," Ms Attwood added.
National co-ordinator of the Campaign against Climate Change Phil Thornhill called for the "full disclosure" of tests carried out by the airport on pollution levels.
London City airport was unavailable for comment.'