Japanese Language Stack Exchange is a question and answer site for students, teachers, and linguists wanting to discuss the finer points of the Japanese language. It only takes a minute to sign up.
Sign up to join this community
One of my grammar books 日本語総まとめN2 文法 lists both of the grammar forms 「きっかけに」 and 「契機に」 in the same definition.
However, in the example question a choice is given between them:
その事件（a. の契機に b. をきっかけに)、商品の検査体制が見直された。
The book lists "b" as the correct answer, yet I'm still puzzled as to why either of them would be more appropriate than the other.
Is it the case that 「契機に」 has a much more limited/specific use compared to the other?
The problem is the particle. 契機 or きっかけ both take を, not の. を契機に or をきっかけに is fine.
〜契機に is used when the 文末 has a good/positive meaning. Otherwise, their meaning and usage is basically the same. My book says that it is more of a formal and/or written expression.
Your example sentence is like "Because of that incident, the inspection method of the merchandise was reevaluated", and seems like an overall negative meaning. Even though reevaluation can be a good thing, the mood of the whole sentence seems negative. Compare that to the mood of this sentence:
今度の病気、入院を契機に、今後は定期検診をきちんと受けようと思った。 → "(After) being hospitalized by my last illness, I decided that I'll be good about getting regular checkups."
Even though the sentence started out negative (hospitalization), the person made an encouraging/positive decision at the end.
