Chris Froome has admitted that failing a drugs test at this year’s Vuelta a España has been damaging to his reputation – but again insisted he did not overstep any boundaries.

The four-times Tour de France winner also nodded in agreement when it was put to him that the world knew about his adverse analytical finding on 7 September only because of investigative work carried out by two newspapers, the Guardian and Le Monde – suggesting that Team Sky, British Cycling and cycling’s governing body, the UCI, were planning to keep the news secret.

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Speaking to Sky Sports News, Froome said: “Sure, this is damaging. It has come as a huge shock to me. But at the same time, I know that within me I have fundamentally followed the protocol. I have not overstepped any boundaries and I hope by the end of this process that will be clear to everyone and I will be exonerated of any wrongdoing.”

Froome insisted that he had provided the UCI with data that he hoped would explain why he had double the legally permitted amount of the asthma medication salbutamol in his urine.

“We also have a wealth of information from within the team about what I ate every single day, how many times I stopped to pee during the race every day,” he said. “We know the number of puffs of my inhaler I use to treat my asthma and at what times.

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“The detailed information we have been able to provide the authorities is vast, and I hope we will be able to find out the real cause of the problem,” he added.

The former head of the UCI Brian Cookson, who is British, denied knowing of Froome’s failed test while he was president and insisted he did not have any “role or influence” in the case. Cookson, whose four-year tenure ended on 21 September with a shock defeat to the Frenchman David Lappartient in the election, added that, under procedures he introduced, anti-doping matters were handled by the independent Cycling Anti-Doping Foundation and the Legal Anti-Doping Service.

“As UCI president I therefore had no role or influence in any individual case,” said Cookson, “I had then, and still have today, confidence in the integrity of all those involved, that they would always follow the correct procedures in every case, and that no rider was treated in any way differently from any other.”

Meanwhile the four-times world time trial champion Tony Martin said it is a “scandal” that Froome competed in the world championships in Norway on 21 September – when he had found out a day earlier that there had been an adverse analytical finding against him.

Q&A What is salbutamol? Show Hide Salbutamol is medication used to relieve symptoms of asthma – and other lung conditions – such as coughing, wheezing and feeling breathless. It works by relaxing the muscles of the airways into the lungs which makes it easier to breathe. It is taken normally through an inhaler, although it can also be ingested as a tablet, capsule or syrup. Under Wada rules, riders are allowed a level of 1,000 nanogram per millimetre. The presence in urine of salbutamol in excess of that is presumed not to be an intended TUE and will be considered as an 'adverse analytical finding' unless the athlete proves that the abnormal result was the consequence of the use of the therapeutic dose (by inhalation) up to the maximum dose indicated above. Salbutamol is not something you need a TUE to take.

Writing on his Facebook page, Martin said: “I am totally angry. There is definitely a double standard being applied in the Christopher Froome case. Other athletes are suspended immediately after a positive test. He and his team are given time by the UCI to explain it all. I do not know of any similar case in the recent past. That is a scandal, and he should at least not have been allowed to appear in the World Championships.”

That appears to be a misreading of the rules on Martin’s part, for while with some substances an analytical finding automatically triggers a provisional ban, that is not the case with salbutamol. This means Froome is allowed to compete until his case, which he was told about on 20 September, is resolved.

However, the German, who won a silver medal at London 2012, has also questioned why it took an investigation from the Guardian and Le Monde for the story to come out and questioned whether Sky had a special status in cycling.

“Not only the public but also I have immediately the impression that there is wheeling and dealing going on behind the scenes, agreements are being made and ways are being sought as to how to get out of this case,” he said. “Do he and his team enjoy a special status?

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“These actions are a major blow to the difficult anti-doping fight, which I am leading with riders like Marcel Kittel. We need a consequent and transparent approach by the UCI. What is going on here is inconsequent, not transparent, unprofessional and unfair.”

The Guardian understands that Froome and Team Sky have recruited a team of medical and legal experts to seek an explanation of the findings. In particular, they are examining whether Froome was dehydrated at the time, or whether there were other physiological factors that may have led to the failed test.

One of the possibilities that will be offered to Froome is for a simulated test where he takes salbutamol and has his urine regularly assessed. However, informed sources expect the case to drag on for several more months – meaning Froome could still be under a cloud when he begins his season next spring.

However, unless Froome can provide a sufficient explanation for the abnormal finding, or challenge the result, he is likely to be stripped of his Vuelta title by the UCI and could be banned for up to 12 months.