Foreign companies from across the globe were trying to determine the damage to their facilities in and around the port, a gateway to north China.
Toyota Motor Corp said windows were broken at its passenger vehicle assembly plant but no one was hurt. The Nikkei newspaper said numerous other Japanese companies sustained minor damage to their operations.
French carmaker Renault said more than 1,000 of its cars were damaged but no staff were hurt. Around 4,000 cars belonging to Hyundai Motor Co were at the site but damage had not yet been assessed, a spokesman said.
Mining giant BHP Billiton said its port operations and shipments were disrupted but its iron ore discharging berth had not been damaged.
Oil tanker arrivals and departures were also disrupted.
John Deere & Co, the US farm and construction equipment maker, said several workers who were at home at the time were injured, some critically.
Xinhua identified the owner of the warehouse as Tianjin Dongjiang Port Ruihai International Logistics. Six senior managers of Ruihai Logistics have been taken under control.
The Tianjin Maritime Safety Administration said the company violated packaging standards during a safety inspection two years ago.
Of 4,325 containers that were checked, five failed the inspection because packaging was sub-standard, according to a report posted on the administration's website in January 2014.
The company's website said it was a government-approved firm specialising in handling "dangerous goods". Phone numbers listed on its website were disconnected and an email to the company went unanswered.
President Xi Jinping said those responsible should be "severely handled".
Tianjin city officials had met recently with companies to discuss tightening safety standards on the handling of dangerous chemicals, authorities said.
People and organizations can donate money through the following three channels:
1. Tianjin Charity Association: Address: No. 9, Shiying road, Nankai district, Tianjin Hotline: 022-234-165-98; 022-234-116-67
2. Postal remittance Receiver: Tianjin Charity Association Postal code: 300381 Address: No. 9, Shiying road, Nankai district, Tianjin (Please write on the envelope: Donation for Tianjin blasts and include your contact information)
3. Online donation: Bank: Shiying Road branch, Bank of China Receiver: Tianjin Charity Association Account: 272660066284 (Please write: Donation for Tianjin blasts and include your contact information)