Moses Kiptanui, tipped to be Kenya's next head coach, spoke out on Friday against the recent spate of doping cases involving Kenyan athletes.
Kiptanui is tipped to become Kenya's new national coach
The three-time 3,000m steeplechase world champion said he was dismayed to see the name of Kenyan athletics being sullied.
Kiptanui's comments come after former 1500m silver medallist Bernard Lagat was provisionally suspended by Athletics Kenya (AK) after testing positive for blood-boosting supplement EPO - known to aid distance runners' performances.
"While the majority of Kenyan athletes excel due to natural talent, the few who are using performance-enhancing substances are just overambitious runners who want to reach the top by dubious methods," Kiptanui said.
"This is greed, nothing else. They are spoiling the reputation that we helped to build over the years.
"But they should realise that they are not only spoiling the image of our beloved sport but making their own lives very dangerous."
On Thursday, AK chairman Isaiah Kiplagat said the International Association of Athletics Federations (IAAF) had informed him Kenyan runner Ambrose Bitok failed a drug test at a meeting in Linz on 19 August.
Bitok, a 5,000m runner, had tested positive for the performance-enhancing drug norandrosterone, Kiplagat said.
Like Lagat, his A sample tested positive and, according to procedure, he is provisionally suspended pending results of the B sample.
Pamela Chepchumba was handed a two-year ban after testing positive for EPO at the world cross country championships in Lausanne in March.
Double Olympics gold medallist Kip Keino has been asked by AK to head a team to probe why doping cases are on the rise.
Kiptanui, who is expected to replace Mike Kosgei as national coach following the latter's sacking this week, defended the performance of the Kenyan team in Paris.
Kenya finished equal seventh on the final medals table with two golds, one silver and a bronze.
"We need to train together for longer period than is the case currently to instil team work and camaraderie. This is why Ethiopia did better this time," said Kiptanui.
Meanwhile, the Kenyan government has given AK one week to explain why they cleared the athlete formerly known as Stephen Cherono to run for Qatar in last month's Paris world championships.
The 3,000m steeplechase world champion, now known as Saif Saaeed Shaheen, was allowed to switch nationality and went on to take gold.