Apartment problems

I know this is not the best community for this, but you folks seem to know a lot about renting laws. If there is a better community you can direct me to, please do.

I and my two roommates rent a basement apartment in Boston. We've had a lot of problems with the pipes (they're generally very loud, one has been leaking off and old since October) and especially the bathroom. Usually at about once a day, sometimes less, sometimes much more, the water will drain out out the toilet with a loud bubbling sound. Sometimes there is also a sucking sound in the bathtub when this happens. A few times the toilet has filled up with soapy water. A few times both the toilet and bathtub have filled up with dirty water (water with actual dirt in it).

And twice, they have filled up with human shit.

There is human shit in my bathtub. For the second time. The human shit of, presumably, everyone in my apartment building.

Like most landlords, mine like to do things themselves. So, while we obviously don't call them every time the toilet makes noises, we have called them each time about the feces, the dirt, and the bubbles. Because there is clearly a fucking problem here. Only once did they bring a plumber. That time they found that someone had ben flushing pads and accused "the female" (my roommate) of flushing them. She's not stupid and she doesn't flush pads. When we called this time they asked again if we have flushed anything unusual. We do not because, again, we aren't stupid and we don't enjoy having shit in our bathtub.

Adding to the problem is that there is a sizable language barrier between my roommates and the landlord.

I do not know what to do if they do not bring a plumber today. This is clearly a bigger problem can can be solved by spitting in my toilet and turning the shower on with your clothes on, which is all the landlord seemed to do yesterday when there was dirt water in the bathtub. They clearly cannot fix this alone. It sounds to me like something that involves all the fucking pipes in the city of Boston, but how would I know, I'M NOT A FUCKING PLUMBER AND NEITHER IS HE. How do I make them fix this? What agencies can I refer them to to force them to do their jobs? Can I call a plumber myself for another opinion and take that out of the rent? Can I take money out of the rent for pure fucking pain and suffering (including bladder pain because, hello, none of us can pee until they come deal with this)?

Help me.

Summary: My landlords do not have the skills do deal with plumbing problems that clearly affect the health of my roommates and I and are extremely resistant to calling a plumber. What recourse do I have?

EDIT: Thanks for all your comments. Yesterday the landlord told us they couldn't find a plumber, so I got one myself (after a Google search and a phone call, shocker, there are a lot of plumbers in Boston) and a few hours later, we had someone snaking the main drain. They found a couple tampons, so I think it's possible that when the landlords said pads before, they meant tampons.

The landlords cleaned the bathroom for us, but I am still going to contact the Board of Health on Monday. The toilet has already made a bubbling sound a few times and when I came home from staying at my girlfriend's fifteen minutes ago there was a puddle of rust water on the floor outside the bathroom and the pipes were even louder than usual.

The landlords really dragged their heels on this shit and kept trying to pin it on us, even though the three plumbers who came all said it was a problem with the main drain and not our specific toilet, as the landlord said. They told us last time that they would circulate a letter reminding people not to flush anything they shouldn't be (anything other than human waste and toilet paper), but I don't know that I believe that that happened.

The toilet, as it happens, is brand new; a few months ago a hole developed in the tank of our old one and it had to be replaced. I think the dirt thing is a bad sign, granted, it seems preferable to the feces.

The best part is that yesterday during all of this, we had two real estate agents call and ask if they could show our apartment.

EDIT: I just got home from work Saturday night and there is bubbles and dirty TP in the toilet and mulch in the bathtub. I dn't know what to do. None of my friends are in the city tonight to take me in and I don't have the money for a hotel.
Call the local legal-aid in your area, and also, the health department. I know with my current landlord, a note from the health department gets him moving VERY quickly.
I 2nd the call to your local health department! This is a huge sanitary violation! He should also be providing you with bleach!
I have nothing to add, but coming from someone who has serious issues with cleanliness, I'm so sorry for what you're living in.
That truly sounds horrid, and nobody should have to wake up to feces in their bathtub. *shudders*
I have nothing useful to add, but my landlord used the same "feminine products" excuse when our plumbing got seriously messed up. Nobody in our apartment was flushing anything crazier than tampons, but they seemed to feel that blaming the tenants was the way to go there, even though the plumbing was screwy before we moved in and they'd been occupying this unit before us.
My parent's house had the sewage backing up problem, tho in their case it backed up through the basement laundry room drain. Get a BIG rubber stopper. When not using the tub, keep the stopper in, weighted down with a shampoo bottle or something if needed. It doesn't SOLVE the problem, but it prevents sewage in your bathtub.
Also, when this problem was happen at my parent's house, it was because tree roots had grown into the pipe that ran from the house to the sewer.
No matter what the circumstance, one should NEVER withhold rent during a landlord dispute. You can place it in an escrow account and have it held there until the problem is fixed (contact your local government to find out how to do this in your area), but you can't arbitrarily decide to withhold rent without all sorts of legal troubles.
From my previous experiences, it sounds like either roots in the pipes or a septic tank issue. If there is a septic tank, there is a small possibility that it could be fixed by using some rid-x. If you have a septic tank, rid-x won't harm anything by trying it. This should help you figure out if you are on sewer or a septic system http://www.inspectapedia.com/septic/septankfind.htm

Of course, I could be completely wrong. Good luck!
I second the opinions of calling the public health board, and would heavily recommend getting the process started tomorrow. Even if they can't actually do much until Monday, the fact that you'd be showing that you just could not take two more days of this may end up working in your favor later (it's also possible that they could question why you waited until Monday, if you do). At the very least, they should be able to give you accurate details of your rights and obligations in this process, including the landlord's obligation. I would not call a plumber myself until I was positive of how this process works, just to be sure of how you're able to recoup your costs. It may take some digging to find an off-hours number, but there should be one somewhere.

Good luck - I've had something similar happen before (thankfully, not the toilet pipes), and it ended up being a giant wet, smelly mess to deal with for weeks. I ended up being moved out, and the apartment was gutted.
I had the same problem in an apartment once, living on the ground floor. After a few times of the bathtub filling up, eventually the toilet overflowed and filled the entire bathroom. I called an emergency plumber since I couldn't reach my landlord and it turned out to be someone flushing stuff like pads and washcloths down the toilet. In my case, the landlord came while the plumber was still working and paid the plumber, but I had a good landlord. I hope things don't get to the overflowing point for you before your landlord fixes it :\
My brother had this problem once, and he lives in a high rise on the 15th floor (of about 20 or so). Luckily the company in charge of the building had a plumber on call and they took care of it. It was indeed random stupid things being flushed down the toilet by another tenant. Unfortunately the plumber and company took care of it so I'm not sure about your recourse, but I just wanted to confirm that the landlord made a pretty sound judgment as to the cause (though accusing one person of being the cause just because she happens to be female is ridiculous). I wish you the best of luck!!

Even when I was young and had just gotten my period it never even occurred to me to attempt to flush something large like that.

I REALLY hope this gets better for you soon. I think no matter what you do, you need to be VERY adamant to your landlord that this is NO LONGER an acceptable solution and you are taking steps to fix this because this is NOT OKAY. Let us know what happens!

That's what I was wondering. Even if somehow the size didn't set off alarm bells (somehow ... ), there's also the fact that most have adhesive on the back, wouldn't one worry that it'd stick to the side of the toilet (inside) or pipe? Yeesh, people are stupid.

And someone else mentioned somebody having flushed washcloths, too! What in the world?!?

OP, I'm sorry, I have nothing useful to add, but it looks like you've gotten lots of good information - so good luck, and tell us what comes of it!
We recently had our main lines (the major outflow pipe from the house to the road) flushed here in Massachusetts. It cost around $350 or so. So, for someone who has the right tools (a main line cleaner, not a regular plumber) it was an easy job and not terribly expensive. Maybe show your landlord some estimates from a few different companies. If it's a building-wide problem a few hundred dollars seems very cheap.

Though this isn't really a court-interest thing, when I had trouble with a landlord in Boston the Harvard Small Claims Advisory Board was extremely kind and helpful. I had no knowledge of landlord-tenant law and they were very prompt and responding and helped me look up the pertinent information in all sections of MGL. They are a free service and I can't recommend it enough.
I am so sorry. We just went through this same problem, in a rental house where we are the only tenants but the landord is a student and wasn't really equipped to deal with this problem quickly. We ended up calling Roto-Rooter and having the line snaked (kept the receipt and she took the amount off the next month's rent) and then not being able to flush solids or take long showers for two weeks while she got estimates to fix the problem (no grade in the line that runs from the house to the sewer line). We got very familiar with the stores in the area that stayed open late. I took in a couple late-night movies so I'd have access to a toilet. I wish you luck. Hang in there and definitely contact your Health Department. At the very least you should get a reduction in your rent due to loss of use. Check for tenants' rights organizations in your area that can give you legal tips on how to proceed. I know in our state there is a requirement that landlords address issues of this nature within 24-72 hours. No one should have to live like this.
Just want to offer you my sympathy. I used to live in a basement apartment in an old building and this happened to me too, a few times over the course of a couple of years. Our landlord was good about getting someone out really quickly and we deducted rubbber gloves, bleach, a new bathmat, and a new mop from our rent (with prior approval from him) each time it happened. There were problems with tree roots and also other people in our building flushing tampons. Good luck and I hope you get it sorted out soon.