Hello aspirant,
Yes, you can pursue Environmental science (hons) with your specification.

Eligibility criteria for B.sc(hons) Environmental science
Candidates who have completed 10+2 or an equivalent examination in asciencestream from a recognized board areeligiblefor B.Sc. (Hons.)Environmental Sciencecourse. Candidates should obtain 55% of marks in their 10+2 examination for B.Sc.

Yes, a PCB student can study Environmental science honours which is a highly interdisciplinary field. The subjects which are taught include ecology, atmospheric sciences, hydrology, geology, environmental chemistry, toxicology, environment pollution, bio-statistics etc. and require an understanding of all basic sciences (Biology, Chemistry and Physics including Math). Other relevant subjects include Environmental studies and environment engineering. First one incorporates social aspects of environment science including resource economics, environment law and governance, social perspectives on environment etc. Second one requires PCM. I am a science graduate (Zoology) and did a master in Environmental studies.