Ignoring spam and profanity in your WordPress blog is like ignoring the entire site altogether. Spam can hurt your SEO rankings and profanity will scare away prospects. Excessive curses and adult language will decrease your online sales and companies will think twice of collaborating with you if your website is profane. Spam can lose your online credibility. Your online credibility is your selling strategy, you lose your credibility, you lose profit.
You need to be wary of these issues if you want your site to be stable and profitable.
This post will give you the best spam and profanity filter plugin for your WordPress website: http://www.wpexplorer.com/wordpress-profanity-spam-filters/