I've been working in this field for over 10 years.
I've been working at this company for over 10 years.
「この仕事に１０年以上携わっています」を直訳すると I've been doing this job for over 10 years になります。I've been working at this company for over 10 years や I've been working in this field for over 10 yearsも大丈夫です。
company - 会社
field - 分野
イギリス 
