id	keyword
gojar-5240	environmental
gojar-5240	nigeria
gojar-5240	air
gojar-5240	pollution
gojar-5240	global
gojar-5240	human
gojar-5240	research
gojar-5240	journal
gojar-5240	act
gojar-5240	laws
gojar-5240	government
gojar-5240	vol
gojar-5240	gojar
gojar-5240	air pollution