The owners of the Assmang manganese processing plant...where at least 50 workers are suspected to be suffering from the crippling condition manganism, were warned as early as 1995 about the dangers of high levels of dust at the plant...Jan Steenkamp, an executive director at Assmang, admitted that [occupational hygienist] Occutech had warned the company...Steenkamp said Assmang reduced its levels after Occutech's recommendation, but conceded that conditions needed to be improved because the plant was old. [Assmang is jointly owned by Assore and African Rainbow Minerals].