of the campus, many of which afford a pleasant view of the Seine River. Controversies and asbestos The campus was often decried as an architectural failure. The hollow space under the building wings enables wind to build up its force, and thus the environment on the slab is unfriendly. Sound-proofing is very poor, with classes regularly having to briefly stop when someone flushes the toilet next door. The regular grid plan is confusing, and only long-time residents can move through without going back to the wind-blown ground level, since many corridors do not allow through-crossing (laboratories etc. have often chosen to lock their corridor for safety reasons). The campus had increasingly deteriorated since its construction, and its older tower stairwells and exteriors were covered in perpetual graffiti. The most worrisome aspect of the Jussieu architecture was its extensive use of asbestos as a fire retardant. Asbestos fibers are carcinogenic when inhaled. As a consequence, the use of asbestos in buildings is prohibited in France, but was not at the time when the campus was built. The risks are particularly acute for workers who maintain the building (drilling walls, for example). In addition, the fire retardation is not considered sufficient, so that its metal frames would collapse in a large fire. An ambitious clean-up program was begun in 1997 after some high-profile protests. The wings are stripped of all equipment, walls, etc., down to the naked concrete frame, and are then rebuilt using more modern materials. Many advocated the destruction of Jussieu when the asbestos problem was addressed. However, the campus is protected as an architectural type, and must be restored to its original condition. In 1996 Claude Allègre, a well known French politician and former scientist, opposed the removal of asbestos from the campus, describing it as harmless and dismissing concerns about it as a form of "psychosis created by leftists". The campus' asbestos is deemed to have killed 22 people and caused serious health problems in 130 others. The 1997–2016 refurbishment completely removed the asbestos. This was also an opportunity to rebuild the campus to be more friendly to its inhabitants. The graffiti were removed; sound proofing and thermal isolation was added; many of the round stairwells were replaced by straight ones; openings were made to create vistas and let in light; the prefabs were destroyed and replaced by gardens; courtyards were covered by transparent roofing; a dry garden