A Napier Port spokesman said no ammonium nitrate is stored at the port.
"Safety comes first at Napier Port," he said. "We have rules and regulations for handling dangerous goods in our container terminal, in accordance with current Government legislation.
"The use of ammonium nitrate in New Zealand, including the import or storage of the substance, is regulated jointly by the Environmental Protection Agency and WorkSafe New Zealand.
"In accordance with these regulations, Napier Port do not allow for any amount of ammonium nitrate to be stored on port."
Ammonium nitrate, an additive to fertiliser for helping nitrogen-poor soil, has been behind several explosions in the past, both accidental and deliberate.
The chemical was used in a terror attack in 1995 in Oklahoma City - the worst domestic terrorism on US soil.
The bomb exploded outside a federal building, causing several floors to collapse, killing 168 people, with hundreds more injured.
Ammonium nitrate was also behind a deadly explosion in Tianjin, China in 2015, which left 173 people dead in the port city.
The Napier Port spokesman said dangerous goods of any class that enter the container terminal must be notified and transported in accordance with the specific regulations, restrictions and set timeframes regulated by the Environment Protection Agency (NZ), Land Transport (NZ) and WorkSafe NZ.
There are 21 New Zealanders registered on SafeTravel as being in Lebanon at the moment, a spokeswoman for the Ministry of Foreign Affairs and Trade said.
A total of 10 Kiwis are registered as being in Beirut.
The blast, which killed at least one Australian, has lead to a two-week state of emergency to be declared in the area.