On Thursday afternoon, 217 military nuclear and chemical specialists arrived armed with detecting devices.
A total of 3,500 residents have been relocated to 10 nearby schools after their homes suffered damages mainly due to the blast shockwave.
The number may reach 6,000 by Thursday night, Zhang Yong, head of the Binhai district government, said at a press conference.
Daily necessities including water and food, together with 800 folding beds and 1,600 towels have been allocated to each relocation site.
The city has set up 17 monitoring stations for air, and another five for water. Three sewage outlets to the sea have been closed, said Wen Wurui, head of the city's environmental protection bureau, at the press conference.
Wen added that the blast will not affect the air quality in Beijing, about 120 kilometers northwest to Tianjin.
About 1,000 medics in Binhai New District are treating the injured.Tianjin health authority said it had also organized 110 experts from nearly 30 hospitals citywide to lead the treatment and provide counselling for the injured.
The National Health and Family Planning Commission has already sent 35 experts from top hospitals in Beijing to help treat the critically injured.
"We will use the best of our resources to save the injured," said Wang Jiancun, director of Tianjin Health and Family Planning Commission.
According to Wang Xiaojie, head of the emergency department of Teda Hospital, many patients had glass or shrapnel cuts, or skull injuries and fractures.
The city with a population of over 15 million is mobilized. Volunteers arrived at hospitals to donate blood, and taxi drivers and private car owners offered help to transport the wounded to hospitals.
Several hotels have offered free accommodation and meals to displaced residents.
In TEDA No.2 Primary School, 50 volunteers helped distribute clothes, food and drinks to about 1,500 residents who were relocated. Some residents also helped the efforts, handing out free bottled water, snacks and facial masks on streets near the resettlement sites.
One volunteer, Duo Mingzhu, arrived at the scene around 2 a.m. Thursday, with her husband. They helped to handout water and bind wounds for the injured.
"We felt so upset after we heard about the explosion. Helping to take care of them is the only thing we can do," said Duo.
The Fifth Center Hospital of Tianjin said they had received more than 500 blood donors in three hours after the blasts, and long lines could be seen in the city's blood stations on Thursday.
The warehouse was owned by Tianjin Dongjiang Port Rui Hai International Logistics Co. Ltd., which was founded in 2011 and is a storage and distribution center of containers of dangerous goods at the Tianjin Port.
