Your comment implies that women have not sought greater representation in these industries. That could not be more wrong.

Allow me to copy a quote from this subreddit from a few weeks ago by /u/cass314:

But here you go--just a handful of the neat news articles about women who are trying to break into forestry, construction ( 1, 2 ), fire, and sanitation in the US and other countries as well. (Sanitation jobs are actually quite hard to get in many municipalities, by the way. In NYC, you have to sit an exam--with about 30k others--and could wait the better part of a decade to get in!)

Women do try to break into dirty and dangerous jobs. It's worth noting that they often face a lot of pushback from the men in those jobs when they do so, especially in jobs like fire and the armed forces. However there is a fair bit of research funded on the subject and even very mainstream attempts to correct these disparities. So it isn't like the question is being ignored.

And anyway, if men's jobs are so undesirable, I wonder why men aren't reciprocally lining up to be equally represented in the presumably much easier heavily female undesirable jobs. For example as home health aides (about 90% women) who are required to perform unsafe lifting, are frequently berated by agitated patients of unsound mind, are routinely vomited and defecated upon, and to top it all off, until this very year were one of the few professions actually exempted from the minimum wage? (By the way, even in female-heavy professions, men have an advantage in promotion and pay, so that should be something of an incentive.) Maybe it's because issues like this are complicated and can't be summed up with pithy declarations of "I'll care about x when y."

If you did not intend to insinuate that women are not pursuing greater representation in "dirty" male-dominated industries, feel free to clarify via an edit to your original comment. Thanks.