evidence: Fact Check: Will camphor, clove, ajwain and a few drops of eucalyptus oil help in increasing oxygen level? Know here [...] The viral post which has also been shared by Union Minister Mukhtar Abbas Naqvi says that camphor, lavang (clove), ajwain and a few drops of eucalyptus oil help in increasing oxygen levels and congestion. [...] Likewise, there is no study that suggests that clove, ajwain and eucalyptus oil increase oxygen levels and congestion.