A toxicologist had concluded that there was no clinical evidence that a father left paralysed by suspected fumes, which are believed to have killed his seven-year-old son, had been exposed to deadly hydrogen cyanide gas, an inquest has heard.
Kye Gbangbola, 50, has told the hearing how he lost consciousness, suffered extreme blistering and permanently lost the use of his legs after being found at his home in Chertsey, Surrey, during a period of severe flooding on the same night that his son Zane was discovered lifeless in bed.
Zane’s parents believe that highly toxic hydrogen cyanide may have seeped into the property in flood water from a nearby lake, which was a former landfill site.
Giving evidence at Woking coroner’s court, Zane’s father was asked about a letter sent by Dr David Wood, a consultant physician and clinical toxicologist, which said: “There is no clinical evidence of exposure to hydrogen cyanide. It is likely there was exposure to carbon monoxide.”
The Surrey coroner, Richard Travers, has been presented with a competing theory that Zane may have died of carbon monoxide poisoning, possibly from a petrol pump that his mother, Nicole Lawler, 39, hired the day before – a pump that the couple claim that they did not use.
Alison Hewitt, the counsel for the inquest, said Wood’s letter suggested that Gbangbola’s rhabdomyolysis, the muscle destruction that has left him in a wheelchair, could have been caused by carbon monoxide, which would explain the elevated levels of 10.5% carboxyhemoglobin in his blood gases when he was admitted to hospital.
Gbangbola, who described himself as the managing director of an independent assurers consultancy and a peer reviewer of hospitals, told the inquest he was “shocked” by the letter, which was “inaccurate” and did not reflect the consultation that he had with Wood, in whom he had since “lost confidence”.
“The carbon monoxide to us is a theory which had no basis in fact,” Gbangbola said, adding that the house was solely electric. “We knew there was no petrol pump running, no carbon monoxide in the house.”
Gbangbola, who has sickle cell anaemia, said from his own research, levels of carboxyhemoglobin at 10% were “asymptomatic”. Zane’s level was 8%. “Nobody dies at 8%” he said.
There were “umpteen references” in the records to hydrogen cyanide being present on the night, Gbangbola said: in a doctor’s report, in a Health Protection Agency report that referred to “small pockets” of the gas and a police report that referred to “low levels”.
“Hydrogen cyanide leaves a person rapidly,” Gbangbola said. “Dr Wood is a toxicologist; he would know that hydrogen cyanide leaves the system when blood levels are measured days later.”
The inquest has heard that the petrol pump was found in a ground-floor toilet at the rear of the family home.
Surrey Hire and Sales, where Lawler hired the pump from, has told the coroner that the company gave “clear and unambiguous” advice that it should not be used indoors. Lawler said she was told that the equipment could be used indoors, provided a window was open, but that it was not used other than very briefly to set the pump up.
Gbangbola was questioned about references made by medics in police statements, and in his health report that he had sent to the coroner, which suggested that the pump was running during the afternoon.
In his report to the coroner, Gbangbola had referred to the pump being switched off at 6.30pm, Hewitt said. Gbangbola said this was a “typo” and that he had written the report while in hospital, on morphine and in a wheelchair. “I missed it [the typo],” he said. “I was contending with some quite serious life issues, having been in a life-threatening situation.”
Gbangbola denied telling a police officer that the pump had been running between 10am and 2.30pm the day before Zane’s death in the early hours of 8 February 2014, though not continuously, because it had run out of petrol.
He was questioned by Chris Coltart QC, for Surrey Hire and Sales, about a statement given by one doctor treating Gbangbola at the hospital, which said the pump was running until five hours before Zane was discovered at about 3am.
“If you told him [the doctor] that, that would imply it had been running until 11pm,” Coltart said. “If I had told him,” replied Gbangbola. “But I didn’t tell him.”
The hearing continues.
