The sum represented 1.5% of the company's total annual turnover derived from polypropylene products, it said in a statement.
The commission further referred complaints of collusion and excessive pricing in the plastics sector against Sasol Chemical Industries and Safripol to the Competition Tribunal for adjudication.
Polypropylene is a type of plastic and used to make, among others, packaging and textiles.
The commission initiated the investigation in 2007 following concerns raised by the trade and industry department about pricing in the sector and its negative effect on growth and employment in manufacturing.
The commission found Sasol had charged excessive prices for its plastic products to its local customers, in line with import parity pricing.
Further, it was concluded that Sasol and Safripol engaged in collusive conduct.
"Sasol is the dominant supplier of propylene (the raw material used to make polypropylene), for its own use and that of Safripol.
It is also the major supplier of polypropylene to the South African market along with Safripol."
The commission said it had found South Africa was also a major exporter of polypropylene, reflecting its competitive position in this product.
"One would therefore have expected pricing to local customers to be on the same basis as export prices, however, this is not the case."
"The competitiveness of local manufacturers in these relatively labour intensive activities depends on competitively priced polypropylene input," the commission added.
It said the case was an important one as it went to the heart of the government's objective to support employment creation and growth.
The commission said it was seeking a penalty of 10% of Sasol's annual turnover for each of these
contraventions.
- Sapa