At least six people were killed in the blasts according to Iraqi state broadcaster, but the US military has so far only confirmed the deaths of two Iraqi policemen in the second explosion, which occurred in Ameriyah, outside Fallujah.
"Coalition forces confirmed that the Ameriyah citizens exposed to the chlorine were treated locally for symptoms ranging from minor skin and lung irritation to vomiting," Hollenbeck said in a statement.
Brigadier General Abdel Karim Khalaf, Iraqi interior ministry operations director, suggested the bombings may have been carried out in response to recent government operations against fighters in Ramadi.
Fighters have modified their targets, adding gas bombs to their arsenal, after Iraqi and US forces recently launched a large-scale operation in and around the capital Baghdad to quell violence.
There have been five 'dirty bombings' since January 28 in the western Anbar province, with two similar bomb blasts reported in the capital Baghdad.