The article mentions other chemicals: > Families living closer to fracking wells also had higher levels of chemicals, such as 1,2,3-trimethylbenzene, 2-heptano

The article mentions other chemicals: > Families living closer to fracking wells also had higher levels of chemicals, such as 1,2,3-trimethylbenzene, 2-heptanone and naphthalene, than families living further away.