Shockwaves of the Iran war hit traders at China's largest trade fair in the southern city of Guangzhou, where more than 32,000 exhibitors are showcasing products over an area larger than 200 football fields.

As Iran is a major exporter of sulfur, the war disrupted sulfur supplies causing the price of sulfuric acid to rocket-high. Consequently, copper mines in South America have been forced to shut down or cut production.

Hu Yufu, General manager of Hanyang Hangzhou Cable Co., Ltd. said the price of copper, a critical input for his business, has surged by 4,000 yuan ($550) per ton in just one week.

“Previously, prices were more stable, but now the price changes of raw materials are large and fast,” Hu added and describe the Cooper market "high unpredictability”.

Taimu Electrical (Hangzhou) Co., LTD, who relies on the Middle East for 10% of its sales of low-voltage circuit breaker, halted its business in Saudi Arabia and Dubai.

“Marketing promotions and personnel exchanges are all affected by flight cancellations. Our logistics are also impacted. Originally, we planned to have sales of 20 to 30 million (RMB) in the Middle East in the first half of the year, but currently all projects are suspended,” Wang Yuqing, Sales Director of the company said.

Wang said the cooperation with Russia since last year has helped offset some losses for the company.

Price of plastic raw materials, which is derived from crude oil, surged by 20% since the conflict, said Shao Haixia, general manager of Xiatao Plastic Industry Co., Ltd.

"It is very difficult for foreign trade companies,” Shao said in her company’s booth with plastic accessories for electrics on display.

For international visitors to the Canton Fair, the journey became a test of endurance and wallet for some. Juliana Amaral, a buyer from Brazil, found her flight to Guangzhou was forced to reroute through Italy instead of Dubai.

“I have to change our flight and it was very bad because ticket gets three times higher than the ordinary ticket. And we spent 48 hours to get here,” she said.

The Canton fair, which takes place from April 15 to May 5 in three phases, provides a barometer of trade in China.

Production: Xihao Jiang/Reuters