( CNN ) -- Visitors to the Tate Modern gallery in London on Friday have been stopped from walking on a porcelain sunflower seed art installation by the maverick Chinese artist Ai Weiwei . Members of the public had previously been encouraged to interact with the installation by walking among and handling the 100 million hand-crafted porcelain seeds . But Tate officials now say that walking on the artificial seeds , which lay in an inch-thick carpet in the gallery 's massive Turbine Hall , has generated more dust than expected . `` Although porcelain is very robust , the enthusiastic interaction of visitors has resulted in a greater than expected level of dust in the Turbine Hall . Tate has been advised that this dust could be damaging to health following repeated inhalation over a long period of time . `` In consequence , Tate , in consultation with the artist , has decided not to allow visitors to walk across the sculpture , '' the statement by Tate Modern said . The installation is still open to the public , who can view the replica seeds from a first floor platform . A spokesman for Tate Modern told CNN that the public are unlikely be allowed to interact with the exhibit again . This is not the first time the gallery has experienced problems with an exhibit in the Turbine Hall . In 2006 the Tate had to hand out cloth sacks to visitors for an exhibition that consisted of metal slides by the artist Carsten Höller . Officials were worried that members of the public could experience burns on the slides . And in 2007 the gallery had to put up warning signs for a sculpture by Doris Salcedo called Shibboleth -- a huge artificial crack in the floor of the Turbine Hall . The sculpture by Ai -- described by some as China 's `` Andy Warhol '' -- is the 11th commission in the internationally acclaimed Unilever Series at the gallery , an annual series kicked off in 2000 by Louise Bourgeois 's spiders and mirrors . Ai 's seeds are porcelain , each one individually handcrafted by laborers in the Chinese city of Jingdezhen . Each tiny piece has been individually molded and hand-painted , according to the gallery . Sunflower seeds are a popular Chinese street snack and one of the country 's most famous exports , according to the gallery . But they hold greater significance for Ai , who spent his childhood in Xinjiang as the son of a celebrated poet exiled by the Chinese communist government during the Cultural Revolution . He told CNN : `` It was very poor and rural there , we had nothing else to enjoy . Sunflower seeds were something basic that everyone could have . Every holiday , wedding or even just going to the movies , we would all share sunflower seeds with one another . I think it 's a very common , very inconspicuous object , but it also has a special relationship to our daily lives ... Of course , during the cultural revolution we all knew that the Sun symbolized the leader , and sunflowers represented the people . So I think these seeds carry multiple meanings . '' Ai is a well-known and controversial figure in China , probably best-known today for the design -- in collaboration with Herzog & de Meuron -- of Beijing 's `` Bird 's Nest '' stadium , built for the 2008 Olympics . Shortly after , Ai -- who is one of China 's leading social activists and bloggers -- distanced himself from the Olympics calling for a boycott and saying the Chinese government was using them as propaganda . In the 1990s , Ai came to international attention when he helped establish the avant-garde East Village in Beijing where a group of artists took up residence in impoverished migrant workers housing on the city 's outskirts . It became a Mecca for radical Chinese contemporary artists like Ma Liuming . Other notable large-scale artworks that have filled the Tate Modern 's Turbine Hall include Carsten Hollers ' slides which had visitors shouting with excitement as they slid down ; Olafur Eliasson 's giant projection of the sun in `` The Weather Project '' and a huge crack in the floor courtesy of Doris Salcedo 's `` Shibboleth . '' CNN 's Eileen Hsieh contributed to this story .
Visitors stopped from walking on carpet of seeds . Interaction with porcelain seeds generating too much dust , says Tate Modern . Ai famous for co-designing Beijing 's `` Bird 's Nest '' stadium . Also well-known blogger and outspoken critic of Chinese government .