Will the Beirut explosions cause a humanitarian disaster?

Lebanon was in a dire state even before Tuesday’s explosions in Beirut.
The government is bankrupt, millions of Lebanese are jobless, and the country is hosting 1.5 Syrian refugees.
The huge blast made things worse by destroying the main port for a nation heavily reliant on food imports.
300,000 homeless people Beirut have received little help from the government.
How will aid organisations deal with the challenge?