Tianjin Bohai Chemical Industry (Group) Co's net profit has dropped 36 per cent in the first half due to plunging product prices - despite a 2 per cent rise in sales. The mainland marine chemical maker said attributable profit was 47.72 million yuan (about HK$44.4 million), with sales at 1.42 billion yuan. The H-share company got a 22.23 million yuan government tax rebate for developing new products. The amount was exempted from income tax. The company blamed cut-throat competition and an import surge for the lower prices of its two major products - soda ash and polyvinyl chloride. The price of soda ash was down 4 per cent from a year ago, while that for PVC dropped even more.