who told you this that chemical is harmful for health ... see there are a lot of myths about this branch which even the people working in industries have.
1.chemical engieering is not at all study of any form of chemistry or reactions.
2.chemical engineering is a specialization of mechanical engineering just like automobile engineering is for mechanical engineering.
3.chemical engineering involves the study of machines,fluids,heat transfer,theory of machines,dynamics and everything you study in mechanical engineering..infact in a lot of colleges like NIT allahabad chemical engineering is a subsidy of mechanical department.
4.chemical engineering has the most amount of prospects after electrical engineering in the country amongst the public sector organisations in the country like ONGC,GAIL,IOC,BPCL,BHEL,IEL,ETC.
5.any industry which is of petrochemical in nature which primarily means a petroleum industry has the highest number of requirements of chemical engineers because each and every work there involves the consultancy of a chemical engineer even if it is not his/her job.
6.people involved in production of machines related to health care and fertilizers and their technology and nuclear power plants are basically pure chemical engineers.
so there is no doubt that chemical engineering is better than civil engineering simply because you have a higher and easier number of choices in psus ..civil engineering is very good and more widespread but involves a lot of private firms and sometimes your setup for a career and also more work involved because you will always have to be outside the office for atleast 20 years of your careers away from ac or coolers... but the biggest disadvantage which has come now a days is that a number of psus hisring civil engineers from college have decided to consider gate score for interviews and qualification so campus placements have reduced significantly...