The British firm Elementis says it is undertaking a strategic review of its chromium chemical unit, a move that usually foreshadows a sale. Benefiting from a postpandemic rebound in industrial activity, the business generated sales of $171 million and a pretax profit of $14 million last year. Elementis bought the business from Occidental Chemical in 2002 for $40 million. It is the only chromium chemical maker in North America. Lanxess sold a similar business in 2019.